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Thermal conductance and resistance

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conspire to make the behavior of heat flow quite unlike the flow of electricity in normal situations. Unfortunately, although the electrical and thermal differential equations are analogous, it is erroneous to conclude that there is any practical analogy between electrical and thermal resistance. This is because a material that is considered an insulator in electrical terms is about 20 orders of magnitude less conductive than a material that is considered a conductor, while, in thermal terms, the difference between an "insulator" and a "conductor" is only about three orders of magnitude. The entire range of thermal conductivity is then equivalent to the difference in electrical conductivity of high-doped and low-doped silicon."
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A 2008 review paper written by Philips researcher Clemens J. M. Lasance notes that: "Although there is an analogy between heat flow by conduction (Fourier's law) and the flow of an electric current (Ohm’s law), the corresponding physical properties of thermal conductivity and electrical conductivity
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Given all this information, the designer can construct a model of the heat flow from the semiconductor junction, where the heat is generated, to the outside world. In our example, the heat has to flow from the junction to the case of the transistor, then from the case to the metalwork. We do not
2363:). The specification for the design should include a maximum temperature at which the circuit should function correctly. Finally, the designer should consider how the heat from the transistor will escape to the environment: this might be by convection into the air, with or without the aid of a 2191:
The heat flow can be modelled by analogy to an electrical circuit where heat flow is represented by current, temperatures are represented by voltages, heat sources are represented by constant current sources, absolute thermal resistances are represented by resistors and thermal capacitances by
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The thermal resistance of materials is of great interest to electronic engineers because most electrical components generate heat and need to be cooled. Electronic components malfunction or fail if they overheat, and some parts routinely need measures taken in the design stage to prevent this.
1894: 3576: 626:: In spacecraft and aircraft, thermal resistance and conductance are critical for managing temperature variations in extreme environments. Designing spacecraft and aviation systems require considerations of thermal conductance and resistance to manage temperature extremes. 6083:
The logarithmic distribution of the temperature is sketched in the inset of the thumbnail figure. Assuming that the temperature distribution, equation 7, is used with Fourier's law in equation 5, the heat transfer rate can be expressed in the following form
602:: Thermal resistance is crucial for designing heat sinks and thermal management systems in electronic devices to prevent overheating. Calculating thermal conductance is crucial for designing effective heat sinks and cooling systems in electronic devices. 4095: 6069: 4369:
The junction-to-air thermal resistance can vary greatly depending on the ambient conditions. (A more sophisticated way of expressing the same fact is saying that junction-to-ambient thermal resistance is not Boundary-Condition Independent (BCI).)
608:: Automotive engineers use thermal resistance to optimize the cooling system and prevent overheating in engines and other vehicle components. Evaluating thermal resistance helps in designing engine components and automotive cooling systems. 4973:
in the radial direction. The standard method can be used for analyzing radial systems under steady state conditions, starting with the appropriate form of the heat equation, or the alternative method, starting with the appropriate form of
2990: 667:: Thermal resistance is considered in climate studies to understand heat transfer in Earth's atmosphere and oceans. Evaluating thermal resistance is useful in studying soil temperature profiles for environmental and agricultural research. 335: 211: 2795: 465:
Objects made of insulators like rubber tend to have very high resistance and low conductance, while objects made of conductors like metals tend to have very low resistance and high conductance. This relationship is quantified by
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A JEDEC standard for measuring the junction-to-case thermal resistance (JESD51-14) is relatively newcomer, having been published in late 2010; it concerns only packages having a single heat flow and an exposed cooling surface.
6224: 1876: 530:. The higher the thermal insulance, the better a material insulates against heat transfer. It is commonly used in construction to assess the insulation properties of materials such as walls, roofs, and insulation products. 3417: 3489: 4599: 3865: 3564: 6336: 5067: 614:
design: Thermal conductance is important for designing cookware to ensure even heat distribution and cooking efficiency. Assessing thermal conductance is important in designing cookware for even heat distribution.
3755:{\displaystyle {\dot {Q}}={{125\ ^{\circ }{\text{C}}-(21\ ^{\circ }{\text{C}})} \over {1.5\ ^{\circ }{\text{C}}/{\text{W}}+0.1\ ^{\circ }{\text{C}}/{\text{W}}+4\ ^{\circ }{\text{C}}/{\text{W}}}}=18.6\ {\text{W}}} 3772:
This method can be generalized to include any number of layers of heat-conducting materials, simply by adding together the absolute thermal resistances of the layers and the temperature drops across the layers.
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It is often suitable to assume one-dimensional conditions, although the heat flow is multidimensional. Now, two different circuits may be used for this case. For case (a) (shown in picture), we presume
2515: 3288: 503:) is a measure of a material's resistance to the heat current. It quantifies how effectively a material can resist the transfer of heat through conduction, convection, and radiation. It has the units 6596:
Schweitzer, D.; Pape, H.; Chen, L.; Kutscherauer, R.; Walder, M. (2011). "Transient dual interface measurement — A new JEDEC standard for the measurement of the junction-to-case thermal resistance".
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Consider a component such as a silicon transistor that is bolted to the metal frame of a piece of equipment. The transistor's manufacturer will specify parameters in the datasheet called the
2783: 645:(MRI) machines and laser systems to maintain precise operating temperatures. Ensuring proper thermal management is crucial for the safety and performance of medical devices and laser systems. 5839: 5762: 4229: 2554:
is the absolute thermal resistance of the bond between the transistor's case and the metalwork. This figure depends on the nature of the bond - for example, a thermal bonding pad or
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Energy efficiency: In the energy sector, thermal resistance and conductance play a role in designing efficient heat exchangers for power plants and energy-efficient appliances.
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This means that the transistor can dissipate about 18 watts before it overheats. A cautious designer would operate the transistor at a lower power level to increase its
2702: 2028: 1997: 1962: 1718: 1637: 2731: 1931: 1077: 4885: 4182: 3169:{\displaystyle {\dot {Q}}_{\rm {max}}={{T_{J{\rm {max}}}-(T_{\rm {amb}}+\Delta T_{\rm {HS}})} \over {R_{\theta {\rm {JC}}}+R_{\theta {\rm {B}}}+R_{\theta {\rm {HA}}}}}} 6803: 6718:
There is a large amount of literature on this topic. In general, works using the term "thermal resistance" are more engineering-oriented, whereas works using the term
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need to consider where the heat goes after that, because we are told that the metalwork will conduct heat fast enough to keep the temperature less than
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and so often use it as an analogy when doing calculations involving thermal resistance. Mechanical and structural engineers are more familiar with
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difference (in kelvins) is required to transfer a unit of heat current (in watts) through the material or object. It is essential to optimize the
3353: 3428: 450:) measures the opposition to the heat current in a material or system. It is measured in units of kelvins per watt (K/W) and indicates how much 4520: 3799: 3500: 6235: 6774: 6755: 6736: 6613: 6566: 6541: 6516: 4986: 661:: Researchers use thermal conductance data to develop new materials for various applications, including energy storage and advanced coatings. 596:: Understanding thermal resistance helps in designing energy-efficient buildings with effective insulation materials to reduce heat transfer. 487: 4835: 673:(HVAC): Understanding thermal resistance aids in optimizing heating, ventilation, and air conditioning systems for better energy efficiency. 2565: 59: 2456:
Suppose the engineer wishes to know how much power can be put into the transistor before it overheats. The calculations are as follows.
5133: 620:: In industries like HVAC and chemical processing, heat exchangers use thermal conductance to efficiently transfer heat between fluids. 6641: 483: 3793:, the following equation can be derived, and is valid as long as all of the parameters (x and k) are constant throughout the sample. 4621: 2260: 81: 4729: 397:. Knowledge of these principles is crucial in various scientific, engineering, and everyday applications, from designing efficient 676:
Thermal packaging: Ensuring proper thermal conductance and resistance is crucial for protecting sensitive goods during transport.
632:: Understanding thermal properties is vital for the design of cryogenic systems used in superconductors and medical applications. 406: 2463: 6824: 3232: 5125:
as a variable becomes evident when the rate at which energy is conducted across a cylindrical surface, this is represented as
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systems: Understanding thermal resistance is important in the design of solar collectors and thermal energy storage systems.
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Similarly to electrical circuits, the total thermal resistance for steady state conditions can be calculated as follows.
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In order to determine the temperature distribution in the cylinder, equation 4 can be solved applying the appropriate
4978:. For a hollow cylinder in steady state conditions with no heat generation, the appropriate form of heat equation is 2739: 700:: Infrared cameras and thermal imaging devices use principles of thermal conductance to detect temperature variations. 2223: 688:
processes: Controlling thermal conductance is essential in processes like welding, heat treatment, and metal casting.
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is the area that is normal to the direction of where the heat transfer occurs. Equation 1 implies that the quantity
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has a standard (number JESD51-2) for measuring the junction-to-air thermal resistance of electronics packages under
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is treated as a variable. Considering the appropriate form of Fourier's law, the physical significance of treating
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are more physics-oriented. The following books are representative, but may be easily substituted.
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surfaces parallel to the x- direction. We may obtain different results for the total resistance
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Tony Abbey. "Using FEA for Thermal Analysis". Desktop Engineering magazine. 2014 June. p. 32.
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Finally, for radial conduction in a cylindrical wall, the thermal resistance is of the form
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and cooking and design equipment for food processing, such as ovens and refrigeration units.
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is the cross-sectional area (m) perpendicular to the path of heat flow through the sample,
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Thermal conductance and resistance have several practical applications in various fields:
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Incropera, Dewitt, Bergman, Lavine, Frank P., David P., Theodore L., Adrienne S. (2013).
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and so often use it as an analogy when doing calculations involving thermal resistance.
330:{\displaystyle {\mathsf {L}}^{-2}{\mathsf {M}}^{-1}{\mathsf {T}}^{3}{\mathsf {\Theta }}} 206:{\displaystyle {\mathsf {L}}^{2}{\mathsf {M}}{\mathsf {T}}^{-3}{\mathsf {\Theta }}^{-1}} 4291: 4240: 3974: 3952: 3930: 2555: 1564: 1516: 1487: 1385: 1361: 1337: 1280: 1256: 1234: 1086: 1029: 1007: 975: 951: 927: 903: 872: 848: 824: 800: 764: 652: 638: 617: 527: 351: 4385:
A JEDEC standard for measuring the junction-to-board thermal resistance (relevant for
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are fundamental concepts that describe the ability of materials or systems to conduct
6813: 6501: 6485: 685: 651:: The food industry uses knowledge of thermal conductance to optimize processes like 474:. However, the nature of a material is not the only factor as it also depends on the 374: 343: 4406:
When resistances are in series, the total resistance is the sum of the resistances:
1107: 697: 679: 569: 504: 439:, and various engineering systems where the controlled movement of heat is vital. 366: 249: 125: 6219:{\displaystyle {{\dot {Q}}_{r}={2\pi Lk(T_{s,1}-T_{s,2}) \over \ln(r_{2}/r_{1})}}} 4155:
is the thickness (m) of the sample (measured on a path parallel to the heat flow),
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The diagram shows an equivalent thermal circuit for a semiconductor device with a
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The diagram shows an equivalent thermal circuit for a semiconductor device with a
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is the thickness (m) of the sample (measured on a path parallel to the heat flow)
1871:{\displaystyle \mathbf {J} =\sigma \mathbf {E} =-\sigma {\boldsymbol {\nabla }}V} 6605: 6598:
2011 27th Annual IEEE Semiconductor Thermal Measurement and Management Symposium
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Spherical and cylindrical systems may be treated as one-dimensional, due to the
2323:), and the maximum allowable temperature of the semiconductor junction (symbol: 2212: 1411: 1406: 1219: 946: 729:
unit of absolute thermal resistance is kelvins per watt (K/W) or the equivalent
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surfaces for those normal to the x- direction, whereas for case (b) we presume
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is the absolute thermal resistance (K/W) across the thickness of the sample,
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is the absolute thermal resistance (K/W) across the thickness of the sample
3412:{\displaystyle R_{\theta {\rm {JC}}}=1.5\ ^{\circ }{\text{C}}/{\text{W}}\,} 4887:
and the actual corresponding values of the heat transfer are bracketed by
3484:{\displaystyle R_{\theta {\rm {B}}}=0.1\ ^{\circ }{\text{C}}/{\text{W}}\,} 6687: 6627: 6625: 6427: 4594:{\displaystyle {{1 \over R_{\rm {tot}}}={1 \over R_{B}}+{1 \over R_{C}}}} 3860:{\displaystyle R_{\theta }={\frac {\Delta x}{Ak}}={\frac {\Delta xr}{A}}} 3559:{\displaystyle R_{\theta {\rm {HA}}}=4\ ^{\circ }{\text{C}}/{\text{W}}\,} 1223: 1136: 922: 790: 554: 508: 369:. The ability to manipulate these properties allows engineers to control 6331:{\displaystyle {R_{t,\mathrm {cond} }={\ln(r_{2}/r_{1}) \over 2\pi Lk}}} 5393:
Hollow cylinder with convective surface conditions in thermal conduction
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is the cross-sectional area (m) perpendicular to the path of heat flow.
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per watt (°C/W) – the two are the same since the intervals are equal: Δ
238: 114: 6691: 4283: 4232: 3420: 819: 428: 2643:{\displaystyle T_{J{\rm {max}}}-(T_{\rm {amb}}+\Delta T_{\rm {HS}})} 5388: 4834: 4500: 4371: 2106:
is the device's absolute thermal resistance from junction to case.
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Advanced Materials for Thermal Management of Electronic Packaging
5231:{\displaystyle {q_{r}=-kA{dT \over dr}=-k(2\pi rL){dT \over dr}}} 2145:
is the absolute thermal resistance from the case to the heatsink.
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Equivalent thermal circuits for series-parallel composite wall
4702:{\displaystyle {R_{\rm {tot}}={R_{B}R_{C} \over R_{B}+R_{C}}}} 4333: 2206: 537: 31: 6682:
Michael Lenz, Günther Striedl, Ulrich Fröhler (January 2000)
4811:{\displaystyle {R_{t,{\rm {cond}}}={L \over (k_{b}+k_{c})A}}} 4721:
With terms for the thermal resistance for conduction, we get
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and another standard (number JESD51-6) for measurement under
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Total absolute thermal resistance from junction to ambient =
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In terms of the temperature gradient across the sample and
726: 641:: Thermal management is crucial for medical equipment like 6729:
Thermal Conductivity: Theory, Properties, and Applications
5357:, it follows from equation 5 that the heat transfer rate, 2510:{\displaystyle R_{\theta {\rm {JC}}}+R_{\theta {\rm {B}}}} 3283:{\displaystyle T_{J{\rm {max}}}=125\ ^{\circ }{\text{C}}} 2558:
might be used to reduce the absolute thermal resistance.
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in industrial processes to optimizing the performance of
6636:. John Wiley & Sons; 7th Edition, Interna edition. 5506:
Using the following boundary conditions, the constants
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We use the general principle that the temperature drop
1817:{\displaystyle \mathbf {q} =-k{\boldsymbol {\nabla }}T} 565: 6561:. Springer Science & Business Media. p. 247. 5902:
and substituting into the general solution, we obtain
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Substituting our own symbols into this formula gives:
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Maximum temperature drop from junction to ambient =
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is the absolute thermal resistance of the heat sink.
4487:{\displaystyle R_{\rm {tot}}=R_{A}+R_{B}+R_{C}+...} 3947:
is the thermal conductivity (W/(K·m)) of the sample
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is the temperature where the heat sink is attached.
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Springer Science & Business Media. pp.  6372: 6330: 6218: 6063: 5894: 5865: 5833: 5756: 5673: 5616: 5556: 5527: 5486: 5415: 5378: 5349: 5327: 5279: 5230: 5117: 5095: 5061: 4953: 4901: 4879: 4810: 4701: 4593: 4486: 4300: 4274: 4249: 4223: 4176: 4147: 4122: 4089: 3983: 3961: 3939: 3917: 3892: 3859: 3754: 3558: 3483: 3411: 3348:(a typical specification for commercial equipment) 3340: 3282: 3215: 3168: 2972: 2777: 2725: 2696: 2669: 2642: 2546: 2509: 2445: 2402: 2355: 2315: 2176: 2137: 2098: 2059: 2022: 1991: 1956: 1925: 1870: 1816: 1773: 1745: 1712: 1676: 1631: 1595: 1549: 1525: 1496: 1467: 1433: 1394: 1370: 1346: 1322: 1289: 1265: 1243: 1204: 1178: 1152: 1126: 1095: 1071: 1038: 1016: 984: 960: 936: 912: 881: 857: 833: 809: 329: 205: 2284:absolute thermal resistance from junction to case 6748:Heat Transfer: Thermal Management of Electronics 6534:Heat Transfer: Thermal Management of Electronics 3969:is the thermal resistivity (K·m/W) of the sample 2778:{\displaystyle \Delta T={\dot {Q}}R_{\theta }\,} 6701:Directed Energy, Inc./IXYSRF (March 31, 2003) 6583:"Experiment vs. Simulation, Part 3: JESD51-14" 5834:{\displaystyle {T_{s,2}=C_{1}\ln r_{2}+C_{2}}} 5757:{\displaystyle {T_{s,1}=C_{1}\ln r_{1}+C_{2}}} 4505:Parallel thermal resistance in composite walls 3781:Derived from Fourier's law for heat conduction 6499:Ho-Ming Tong; Yi-Shao Lai; C.P. Wong (2013). 1884:Explanation from an electronics point of view 713:difference across a structure when a unit of 8: 6703:R Theta And Power Dissipation Technical Note 6656:: CS1 maint: multiple names: authors list ( 4224:{\displaystyle {\frac {\Delta T}{\Delta x}}} 2453:above ambient: this is all we need to know. 6792:Thermal Management for Electronic Packaging 6557:Clemens J.M. Lasance; András Poppe (2013). 4321:Problems with electrical resistance analogy 2677:across a given absolute thermal resistance 2241:. Unsourced material may be challenged and 2272: 671:Heating, ventilation, and air conditioning 482:of an object because these properties are 6769:. Springer Science & Business Media. 6731:. Springer Science & Business Media. 6475: 6445: 6443: 6363: 6350: 6345: 6343: 6301: 6292: 6286: 6270: 6251: 6244: 6239: 6237: 6203: 6194: 6188: 6158: 6139: 6117: 6108: 6097: 6096: 6094: 6092: 6048: 6029: 6020: 5998: 5989: 5983: 5969: 5956: 5937: 5930: 5914: 5912: 5885: 5880: 5878: 5856: 5851: 5849: 5824: 5811: 5795: 5776: 5771: 5769: 5747: 5734: 5718: 5699: 5694: 5692: 5658: 5642: 5631: 5629: 5601: 5585: 5574: 5572: 5547: 5542: 5540: 5518: 5513: 5511: 5477: 5455: 5435: 5433: 5408: 5406: 5369: 5364: 5362: 5342: 5340: 5310: 5294: 5292: 5257: 5255: 5207: 5160: 5142: 5137: 5135: 5110: 5108: 5088: 5086: 5027: 5001: 4991: 4990: 4988: 4945: 4939: 4926: 4917: 4916: 4914: 4894: 4892: 4864: 4859: 4857: 4792: 4779: 4766: 4746: 4745: 4738: 4733: 4731: 4689: 4676: 4664: 4654: 4647: 4631: 4630: 4625: 4623: 4582: 4573: 4562: 4553: 4535: 4534: 4525: 4524: 4522: 4466: 4453: 4440: 4420: 4419: 4413: 4293: 4264: 4242: 4201: 4199: 4168: 4162: 4137: 4114: 4108: 4072: 4049: 4040: 4022: 4013: 4007: 3999:through the sample, the relationship is: 3976: 3954: 3932: 3907: 3884: 3878: 3839: 3816: 3807: 3801: 3747: 3730: 3725: 3720: 3714: 3699: 3694: 3689: 3683: 3668: 3663: 3658: 3652: 3644: 3635: 3629: 3611: 3605: 3597: 3595: 3581: 3580: 3578: 3555: 3550: 3545: 3540: 3534: 3513: 3512: 3508: 3502: 3480: 3475: 3470: 3465: 3459: 3441: 3440: 3436: 3430: 3408: 3403: 3398: 3393: 3387: 3366: 3365: 3361: 3355: 3333: 3327: 3304: 3303: 3297: 3275: 3269: 3245: 3244: 3240: 3234: 3200: 3199: 3188: 3187: 3184: 3152: 3151: 3147: 3132: 3131: 3127: 3109: 3108: 3104: 3099: 3085: 3084: 3061: 3060: 3036: 3035: 3031: 3026: 3024: 3008: 3007: 2996: 2995: 2992: 2969: 2955: 2954: 2950: 2935: 2934: 2930: 2912: 2911: 2907: 2887: 2886: 2875: 2874: 2857: 2856: 2833: 2832: 2808: 2807: 2803: 2797: 2774: 2768: 2753: 2752: 2741: 2712: 2711: 2709: 2688: 2682: 2659: 2627: 2626: 2603: 2602: 2578: 2577: 2573: 2567: 2536: 2535: 2531: 2525: 2499: 2498: 2494: 2476: 2475: 2471: 2465: 2433: 2432: 2423: 2390: 2389: 2380: 2339: 2338: 2334: 2328: 2302: 2301: 2297: 2291: 2261:Learn how and when to remove this message 2163: 2162: 2158: 2152: 2124: 2123: 2119: 2113: 2085: 2084: 2080: 2074: 2044: 2043: 2037: 2013: 2012: 2006: 1982: 1981: 1975: 1947: 1946: 1940: 1912: 1911: 1909: 1860: 1846: 1835: 1833: 1806: 1792: 1790: 1760: 1732: 1693: 1660: 1659: 1648: 1612: 1585: 1571: 1542: 1518: 1489: 1460: 1423: 1418: 1387: 1363: 1339: 1309: 1282: 1258: 1236: 1197: 1195: 1171: 1169: 1145: 1143: 1119: 1088: 1058: 1057: 1055: 1031: 1009: 977: 953: 929: 905: 874: 850: 826: 802: 321: 320: 314: 308: 307: 297: 291: 290: 280: 274: 273: 270: 194: 188: 187: 177: 171: 170: 163: 162: 156: 150: 149: 146: 82:Learn how and when to remove this message 769: 431:(W/K). It is essential in the design of 45:This article includes a list of general 6684:Thermal Resistance, Theory and Practice 6559:Thermal Management for LED Applications 6411: 5487:{\displaystyle {T(r)=C_{1}\ln r+C_{2}}} 5386:is a constant in the radial direction. 3780: 3495:heat-transfer pad for a TO-220 package) 3226:Let us substitute some sample numbers: 759:Electrical engineers are familiar with 6649: 3216:{\displaystyle {\dot {Q}}_{\rm {max}}} 2410:above the ambient temperature. Note: T 1933:is the power dissipated by the device. 322: 309: 292: 275: 217: 189: 172: 164: 151: 93: 29:Materials' resistance to heat transfer 2375:) that is guaranteed to be less than 2316:{\displaystyle R_{\theta {\rm {JC}}}} 2177:{\displaystyle R_{\theta {\rm {HA}}}} 2138:{\displaystyle R_{\theta {\rm {CH}}}} 2099:{\displaystyle R_{\theta {\rm {JC}}}} 488:electrical conductance and resistance 365:and the opposition they offer to the 7: 6634:Principles of Heat and Mass Transfer 5904: 5425: 5127: 4980: 4723: 4615: 4514: 2547:{\displaystyle R_{\theta {\rm {B}}}} 2239:adding citations to reliable sources 1677:{\displaystyle \Delta T={\dot {Q}}R} 2446:{\displaystyle \Delta T_{\rm {HS}}} 2403:{\displaystyle \Delta T_{\rm {HS}}} 709:Absolute thermal resistance is the 6673:The Journal of Physical Chemistry, 6261: 6258: 6255: 6252: 5674:{\displaystyle {T(r_{2})=T_{s,2}}} 5617:{\displaystyle {T(r_{1})=T_{s,1}}} 4756: 4753: 4750: 4747: 4638: 4635: 4632: 4542: 4539: 4536: 4427: 4424: 4421: 4389:) has been published as JESD51-8. 4266: 4212: 4204: 4139: 4075: 4060: 4052: 4025: 3909: 3842: 3819: 3517: 3514: 3442: 3370: 3367: 3311: 3308: 3305: 3290:(typical for a silicon transistor) 3252: 3249: 3246: 3207: 3204: 3201: 3156: 3153: 3133: 3113: 3110: 3089: 3086: 3077: 3068: 3065: 3062: 3043: 3040: 3037: 3015: 3012: 3009: 2959: 2956: 2936: 2916: 2913: 2894: 2891: 2888: 2861: 2858: 2849: 2840: 2837: 2834: 2815: 2812: 2809: 2743: 2661: 2631: 2628: 2619: 2610: 2607: 2604: 2585: 2582: 2579: 2537: 2500: 2480: 2477: 2437: 2434: 2425: 2394: 2391: 2382: 2346: 2343: 2340: 2306: 2303: 2167: 2164: 2128: 2125: 2089: 2086: 2051: 2048: 2045: 2014: 1983: 1948: 1695: 1650: 1614: 1573: 51:it lacks sufficient corresponding 25: 6798:Update on JEDEC Thermal Standards 4831:Resistance in series and parallel 4613:Simplifying the equation, we get 377:, and maximize the efficiency of 18:Thermal resistance in electronics 6668:10. K Einalipour, S. Sadeghzadeh 6373:{\displaystyle {r_{2}>r_{1}}} 4337: 2356:{\displaystyle T_{J{\rm {max}}}} 2211: 1861: 1847: 1836: 1807: 1793: 1198: 1172: 1146: 717:energy flows through it in unit 542: 36: 6536:. CRC Press. pp. 111–113. 5335:is not dependent of the radius 4954:{\displaystyle {|k_{f}-k_{g}|}} 4282:is the temperature difference ( 2367:, or by conduction through the 2067:is the ambient air temperature. 1999:is the temperature at its case. 490:in the domain of electronics. 484:extensive rather than intensive 6307: 6279: 6209: 6181: 6170: 6132: 6004: 5976: 5924: 5918: 5684:The general solution gives us 5648: 5635: 5591: 5578: 5445: 5439: 5321: 5301: 5204: 5189: 4946: 4918: 4798: 4772: 3640: 3619: 3095: 3053: 2966: 2900: 2867: 2825: 2637: 2595: 557:format but may read better as 1: 4512:The total thermal resistance 4231:is the temperature gradient ( 2060:{\displaystyle T_{\rm {amb}}} 437:thermally efficient materials 6727:Terry M. Tritt, ed. (2004). 6503:Advanced Flip Chip Packaging 4397:Resistance in composite wall 1596:{\displaystyle \Delta X=F/k} 1561:lumped element linear model 1205:{\displaystyle \mathbf {j} } 1179:{\displaystyle \mathbf {q} } 1153:{\displaystyle \mathbf {v} } 755:Onsager reciprocal relations 507:kelvins per watt (mâ‹…K/W) in 6765:Xingcun Colin Tong (2011). 6606:10.1109/STHERM.2011.5767204 5401:. With the assumption that 5328:{\displaystyle {kr(dT/dr)}} 5280:{\displaystyle {A=2\pi rL}} 4497:Parallel thermal resistance 4123:{\displaystyle R_{\theta }} 3893:{\displaystyle R_{\theta }} 2697:{\displaystyle R_{\theta }} 2023:{\displaystyle T_{\rm {H}}} 1992:{\displaystyle T_{\rm {C}}} 1957:{\displaystyle T_{\rm {J}}} 1889:Equivalent thermal circuits 1713:{\displaystyle \Delta V=IR} 1632:{\displaystyle \Delta P=QR} 721:. It is the reciprocal of 705:Absolute thermal resistance 6841: 6450:Lasance, C. J. M. (2008). 2726:{\displaystyle {\dot {Q}}} 1926:{\displaystyle {\dot {Q}}} 1072:{\displaystyle {\dot {Q}}} 748: 745:Analogies and nomenclature 643:magnetic resonance imaging 462:in various applications. 6477:10.1080/01457630701673188 6456:Heat Transfer Engineering 6428:"The Design of Heatsinks" 4880:{\displaystyle {R_{tot}}} 4177:{\displaystyle \phi _{q}} 2414:appears to be undefined. 1724:distributed linear model 1606:Hagen–Poiseuille equation 6804:Soil Thermal Resistivity 6688:Infineon Technologies AG 6677:10.1021/acs.jpcc.0c02051 4387:surface-mount technology 4275:{\displaystyle \Delta T} 4148:{\displaystyle \Delta x} 3918:{\displaystyle \Delta x} 3491:(a typical value for an 2670:{\displaystyle \Delta T} 737:= 1 K = 1 Â°C. 6746:Younes Shabany (2011). 6532:Younes Shabany (2011). 5895:{\displaystyle {C_{2}}} 5866:{\displaystyle {C_{1}}} 5557:{\displaystyle {C_{2}}} 5528:{\displaystyle {C_{1}}} 5379:{\displaystyle {q_{r}}} 3179:The designer now knows 2704:with a given heat flow 2556:thermal transfer grease 1642:Newton's law of cooling 1550:{\displaystyle \sigma } 1536:electrical conductivity 1127:{\displaystyle \sigma } 566:converting this section 66:more precise citations. 6825:Electronic engineering 6374: 6332: 6220: 6065: 5896: 5867: 5835: 5758: 5675: 5618: 5558: 5529: 5488: 5417: 5394: 5380: 5351: 5329: 5281: 5232: 5119: 5097: 5063: 4955: 4903: 4881: 4840: 4812: 4703: 4595: 4506: 4488: 4302: 4276: 4251: 4235:·m) across the sample, 4225: 4178: 4149: 4124: 4091: 3985: 3963: 3941: 3919: 3894: 3861: 3756: 3560: 3485: 3413: 3342: 3284: 3217: 3170: 2974: 2779: 2727: 2698: 2671: 2644: 2548: 2511: 2447: 2404: 2357: 2317: 2188: 2178: 2139: 2100: 2061: 2024: 1993: 1958: 1927: 1872: 1818: 1775: 1747: 1714: 1678: 1633: 1597: 1551: 1527: 1498: 1469: 1454:electrical resistivity 1435: 1396: 1381:electrical conductance 1372: 1348: 1324: 1291: 1267: 1245: 1206: 1180: 1154: 1128: 1097: 1073: 1040: 1018: 986: 962: 938: 914: 883: 859: 835: 811: 534:Practical applications 387:mechanical engineering 331: 207: 6375: 6333: 6221: 6066: 5897: 5868: 5836: 5759: 5676: 5619: 5559: 5530: 5489: 5418: 5392: 5381: 5352: 5330: 5282: 5233: 5120: 5098: 5064: 4971:temperature gradients 4956: 4904: 4882: 4838: 4813: 4704: 4596: 4504: 4489: 4402:Resistances in series 4330:Measurement standards 4316:) through the sample. 4303: 4277: 4252: 4226: 4179: 4150: 4125: 4092: 3986: 3964: 3942: 3920: 3895: 3862: 3757: 3561: 3486: 3414: 3343: 3285: 3218: 3171: 2975: 2780: 2728: 2699: 2672: 2645: 2549: 2512: 2448: 2405: 2369:printed circuit board 2358: 2318: 2179: 2140: 2101: 2062: 2025: 1994: 1959: 1928: 1896: 1873: 1819: 1776: 1748: 1715: 1679: 1634: 1598: 1552: 1528: 1499: 1470: 1468:{\displaystyle \rho } 1436: 1397: 1373: 1349: 1325: 1292: 1276:electrical resistance 1268: 1246: 1207: 1181: 1155: 1129: 1098: 1074: 1041: 1019: 987: 963: 939: 915: 884: 860: 836: 812: 665:Environmental science 355:, thermal conductance 332: 243:kelvin per watt (K/W) 208: 119:watt per kelvin (W/K) 6720:thermal conductivity 6395:Thermal design power 6342: 6236: 6091: 5911: 5877: 5848: 5768: 5691: 5628: 5571: 5539: 5510: 5432: 5405: 5361: 5339: 5291: 5254: 5134: 5107: 5085: 4987: 4913: 4891: 4856: 4730: 4622: 4521: 4412: 4292: 4286:) across the sample, 4263: 4241: 4198: 4188:through the sample ( 4161: 4136: 4107: 4006: 3975: 3953: 3931: 3906: 3877: 3800: 3577: 3570:The result is then: 3501: 3429: 3354: 3296: 3233: 3183: 2991: 2796: 2740: 2708: 2681: 2658: 2566: 2524: 2464: 2422: 2379: 2327: 2290: 2235:improve this section 2151: 2112: 2073: 2036: 2005: 1974: 1966:junction temperature 1939: 1908: 1832: 1789: 1759: 1731: 1692: 1647: 1611: 1570: 1541: 1517: 1512:thermal conductivity 1488: 1459: 1417: 1386: 1362: 1338: 1308: 1281: 1257: 1235: 1194: 1168: 1142: 1118: 1087: 1054: 1030: 1008: 976: 952: 928: 904: 873: 849: 825: 801: 524:British thermal unit 371:temperature gradient 269: 145: 6806:for power companies 6790:Guoping Xu (2006), 6468:2008HTrEn..29..149L 6400:Safe operating area 6390:Thermal engineering 5416:{\displaystyle {k}} 5399:boundary conditions 5350:{\displaystyle {r}} 5118:{\displaystyle {k}} 5096:{\displaystyle {k}} 4902:{\displaystyle {q}} 2203:Example calculation 1774:{\displaystyle ...} 1746:{\displaystyle ...} 1449:thermal resistivity 1434:{\displaystyle 1/k} 1357:thermal conductance 1323:{\displaystyle ...} 1253:thermal resistance 785:electrical analogy 776:structural analogy 723:thermal conductance 600:Electronics cooling 594:Building insulation 456:building insulation 417:Thermal conductance 399:temperature control 348:thermal engineering 97:Thermal conductance 6802:The importance of 6794:, Sun Microsystems 6434:2016-09-05 at the 6370: 6328: 6216: 6061: 5892: 5863: 5831: 5754: 5671: 5614: 5554: 5525: 5484: 5413: 5395: 5376: 5347: 5325: 5277: 5228: 5115: 5093: 5059: 4951: 4899: 4877: 4841: 4808: 4699: 4591: 4507: 4484: 4376:natural convection 4349:. You can help by 4298: 4272: 4247: 4221: 4174: 4145: 4120: 4087: 3981: 3959: 3937: 3915: 3890: 3857: 3752: 3556: 3481: 3409: 3338: 3280: 3213: 3166: 2984:and, rearranging, 2970: 2775: 2723: 2694: 2667: 2640: 2544: 2507: 2443: 2400: 2353: 2313: 2189: 2174: 2135: 2096: 2057: 2020: 1989: 1954: 1923: 1868: 1814: 1771: 1743: 1710: 1674: 1629: 1593: 1547: 1523: 1507:fluid conductivity 1494: 1465: 1431: 1392: 1368: 1344: 1320: 1287: 1263: 1241: 1202: 1176: 1150: 1124: 1093: 1069: 1049:heat transfer rate 1036: 1014: 982: 958: 934: 910: 879: 855: 831: 807: 779:hydraulic analogy 568:, if appropriate. 444:thermal resistance 411:electronic devices 407:thermal management 403:thermal insulation 359:thermal resistance 327: 251:SI base units 221:Thermal resistance 203: 127:SI base units 6776:978-1-4419-7759-5 6757:978-1-4398-1468-0 6738:978-0-306-48327-1 6615:978-1-61284-740-5 6568:978-1-4614-5091-7 6543:978-1-4398-1468-0 6518:978-1-4419-5768-9 6325: 6213: 6105: 6081: 6080: 6035: 6008: 5504: 5503: 5248: 5247: 5225: 5178: 5079: 5078: 5045: 5014: 4999: 4828: 4827: 4805: 4719: 4718: 4696: 4611: 4610: 4588: 4568: 4548: 4380:forced convection 4367: 4366: 4310:rate of heat flow 4301:{\displaystyle q} 4250:{\displaystyle A} 4219: 4085: 4067: 4047: 3984:{\displaystyle A} 3962:{\displaystyle r} 3940:{\displaystyle k} 3855: 3834: 3778: 3777: 3750: 3746: 3736: 3733: 3723: 3713: 3702: 3692: 3682: 3671: 3661: 3651: 3638: 3628: 3614: 3604: 3589: 3553: 3543: 3533: 3478: 3468: 3458: 3406: 3396: 3386: 3336: 3326: 3278: 3268: 3196: 3164: 3004: 2883: 2761: 2720: 2271: 2270: 2263: 1920: 1881: 1880: 1668: 1526:{\displaystyle k} 1497:{\displaystyle k} 1444:fluid resistivity 1395:{\displaystyle G} 1371:{\displaystyle G} 1347:{\displaystyle G} 1333:fluid conductance 1290:{\displaystyle R} 1266:{\displaystyle R} 1244:{\displaystyle R} 1096:{\displaystyle I} 1066: 1039:{\displaystyle Q} 1017:{\displaystyle F} 985:{\displaystyle V} 961:{\displaystyle T} 937:{\displaystyle P} 913:{\displaystyle X} 882:{\displaystyle q} 858:{\displaystyle Q} 834:{\displaystyle V} 810:{\displaystyle J} 751:analogical models 692:Geothermal energy 659:Materials science 606:Automotive design 587: 586: 526:(ft⋅°Fâ‹…h/Btu) in 516:degree Fahrenheit 494:Thermal insulance 395:energy management 383:materials science 340: 339: 216: 215: 92: 91: 84: 16:(Redirected from 6832: 6780: 6761: 6742: 6662: 6661: 6655: 6647: 6629: 6620: 6619: 6593: 6587: 6586: 6579: 6573: 6572: 6554: 6548: 6547: 6529: 6523: 6522: 6506: 6496: 6490: 6489: 6479: 6447: 6438: 6425: 6419: 6416: 6379: 6377: 6376: 6371: 6369: 6368: 6367: 6355: 6354: 6337: 6335: 6334: 6329: 6327: 6326: 6324: 6310: 6306: 6305: 6296: 6291: 6290: 6271: 6266: 6265: 6264: 6225: 6223: 6222: 6217: 6215: 6214: 6212: 6208: 6207: 6198: 6193: 6192: 6173: 6169: 6168: 6150: 6149: 6118: 6113: 6112: 6107: 6106: 6098: 6070: 6068: 6067: 6062: 6060: 6059: 6058: 6040: 6036: 6034: 6033: 6021: 6009: 6007: 6003: 6002: 5993: 5988: 5987: 5968: 5967: 5966: 5948: 5947: 5931: 5905: 5901: 5899: 5898: 5893: 5891: 5890: 5889: 5872: 5870: 5869: 5864: 5862: 5861: 5860: 5840: 5838: 5837: 5832: 5830: 5829: 5828: 5816: 5815: 5800: 5799: 5787: 5786: 5763: 5761: 5760: 5755: 5753: 5752: 5751: 5739: 5738: 5723: 5722: 5710: 5709: 5680: 5678: 5677: 5672: 5670: 5669: 5668: 5647: 5646: 5623: 5621: 5620: 5615: 5613: 5612: 5611: 5590: 5589: 5564:can be computed 5563: 5561: 5560: 5555: 5553: 5552: 5551: 5534: 5532: 5531: 5526: 5524: 5523: 5522: 5493: 5491: 5490: 5485: 5483: 5482: 5481: 5460: 5459: 5426: 5422: 5420: 5419: 5414: 5412: 5385: 5383: 5382: 5377: 5375: 5374: 5373: 5356: 5354: 5353: 5348: 5346: 5334: 5332: 5331: 5326: 5324: 5314: 5286: 5284: 5283: 5278: 5276: 5237: 5235: 5234: 5229: 5227: 5226: 5224: 5216: 5208: 5179: 5177: 5169: 5161: 5147: 5146: 5128: 5124: 5122: 5121: 5116: 5114: 5102: 5100: 5099: 5094: 5092: 5068: 5066: 5065: 5060: 5058: 5051: 5047: 5046: 5044: 5036: 5028: 5015: 5013: 5002: 5000: 4992: 4981: 4960: 4958: 4957: 4952: 4950: 4949: 4944: 4943: 4931: 4930: 4921: 4908: 4906: 4905: 4900: 4898: 4886: 4884: 4883: 4878: 4876: 4875: 4874: 4817: 4815: 4814: 4809: 4807: 4806: 4804: 4797: 4796: 4784: 4783: 4767: 4762: 4761: 4760: 4759: 4724: 4708: 4706: 4705: 4700: 4698: 4697: 4695: 4694: 4693: 4681: 4680: 4670: 4669: 4668: 4659: 4658: 4648: 4643: 4642: 4641: 4616: 4600: 4598: 4597: 4592: 4590: 4589: 4587: 4586: 4574: 4569: 4567: 4566: 4554: 4549: 4547: 4546: 4545: 4526: 4515: 4493: 4491: 4490: 4485: 4471: 4470: 4458: 4457: 4445: 4444: 4432: 4431: 4430: 4362: 4359: 4341: 4334: 4307: 4305: 4304: 4299: 4281: 4279: 4278: 4273: 4256: 4254: 4253: 4248: 4230: 4228: 4227: 4222: 4220: 4218: 4210: 4202: 4183: 4181: 4180: 4175: 4173: 4172: 4154: 4152: 4151: 4146: 4129: 4127: 4126: 4121: 4119: 4118: 4096: 4094: 4093: 4088: 4086: 4081: 4073: 4068: 4066: 4058: 4050: 4048: 4046: 4045: 4044: 4031: 4023: 4018: 4017: 3990: 3988: 3987: 3982: 3968: 3966: 3965: 3960: 3946: 3944: 3943: 3938: 3924: 3922: 3921: 3916: 3899: 3897: 3896: 3891: 3889: 3888: 3866: 3864: 3863: 3858: 3856: 3851: 3840: 3835: 3833: 3825: 3817: 3812: 3811: 3761: 3759: 3758: 3753: 3751: 3748: 3744: 3737: 3735: 3734: 3731: 3729: 3724: 3721: 3719: 3718: 3711: 3703: 3700: 3698: 3693: 3690: 3688: 3687: 3680: 3672: 3669: 3667: 3662: 3659: 3657: 3656: 3649: 3643: 3639: 3636: 3634: 3633: 3626: 3615: 3612: 3610: 3609: 3602: 3596: 3591: 3590: 3582: 3565: 3563: 3562: 3557: 3554: 3551: 3549: 3544: 3541: 3539: 3538: 3531: 3523: 3522: 3521: 3520: 3490: 3488: 3487: 3482: 3479: 3476: 3474: 3469: 3466: 3464: 3463: 3456: 3448: 3447: 3446: 3445: 3418: 3416: 3415: 3410: 3407: 3404: 3402: 3397: 3394: 3392: 3391: 3384: 3376: 3375: 3374: 3373: 3347: 3345: 3344: 3339: 3337: 3334: 3332: 3331: 3324: 3316: 3315: 3314: 3289: 3287: 3286: 3281: 3279: 3276: 3274: 3273: 3266: 3258: 3257: 3256: 3255: 3222: 3220: 3219: 3214: 3212: 3211: 3210: 3198: 3197: 3189: 3175: 3173: 3172: 3167: 3165: 3163: 3162: 3161: 3160: 3159: 3139: 3138: 3137: 3136: 3119: 3118: 3117: 3116: 3098: 3094: 3093: 3092: 3073: 3072: 3071: 3049: 3048: 3047: 3046: 3025: 3020: 3019: 3018: 3006: 3005: 2997: 2979: 2977: 2976: 2971: 2965: 2964: 2963: 2962: 2942: 2941: 2940: 2939: 2922: 2921: 2920: 2919: 2899: 2898: 2897: 2885: 2884: 2876: 2866: 2865: 2864: 2845: 2844: 2843: 2821: 2820: 2819: 2818: 2784: 2782: 2781: 2776: 2773: 2772: 2763: 2762: 2754: 2732: 2730: 2729: 2724: 2722: 2721: 2713: 2703: 2701: 2700: 2695: 2693: 2692: 2676: 2674: 2673: 2668: 2649: 2647: 2646: 2641: 2636: 2635: 2634: 2615: 2614: 2613: 2591: 2590: 2589: 2588: 2553: 2551: 2550: 2545: 2543: 2542: 2541: 2540: 2516: 2514: 2513: 2508: 2506: 2505: 2504: 2503: 2486: 2485: 2484: 2483: 2452: 2450: 2449: 2444: 2442: 2441: 2440: 2409: 2407: 2406: 2401: 2399: 2398: 2397: 2362: 2360: 2359: 2354: 2352: 2351: 2350: 2349: 2322: 2320: 2319: 2314: 2312: 2311: 2310: 2309: 2273: 2266: 2259: 2255: 2252: 2246: 2215: 2207: 2183: 2181: 2180: 2175: 2173: 2172: 2171: 2170: 2144: 2142: 2141: 2136: 2134: 2133: 2132: 2131: 2105: 2103: 2102: 2097: 2095: 2094: 2093: 2092: 2066: 2064: 2063: 2058: 2056: 2055: 2054: 2029: 2027: 2026: 2021: 2019: 2018: 2017: 1998: 1996: 1995: 1990: 1988: 1987: 1986: 1963: 1961: 1960: 1955: 1953: 1952: 1951: 1932: 1930: 1929: 1924: 1922: 1921: 1913: 1877: 1875: 1874: 1869: 1864: 1850: 1839: 1823: 1821: 1820: 1815: 1810: 1796: 1780: 1778: 1777: 1772: 1752: 1750: 1749: 1744: 1719: 1717: 1716: 1711: 1683: 1681: 1680: 1675: 1670: 1669: 1661: 1638: 1636: 1635: 1630: 1602: 1600: 1599: 1594: 1589: 1556: 1554: 1553: 1548: 1532: 1530: 1529: 1524: 1503: 1501: 1500: 1495: 1474: 1472: 1471: 1466: 1440: 1438: 1437: 1432: 1427: 1401: 1399: 1398: 1393: 1377: 1375: 1374: 1369: 1353: 1351: 1350: 1345: 1329: 1327: 1326: 1321: 1296: 1294: 1293: 1288: 1272: 1270: 1269: 1264: 1250: 1248: 1247: 1242: 1230:fluid resistance 1211: 1209: 1208: 1203: 1201: 1185: 1183: 1182: 1177: 1175: 1159: 1157: 1156: 1151: 1149: 1133: 1131: 1130: 1125: 1102: 1100: 1099: 1094: 1078: 1076: 1075: 1070: 1068: 1067: 1059: 1045: 1043: 1042: 1037: 1023: 1021: 1020: 1015: 991: 989: 988: 983: 967: 965: 964: 959: 943: 941: 940: 935: 919: 917: 916: 911: 888: 886: 885: 880: 864: 862: 861: 856: 840: 838: 837: 832: 816: 814: 813: 808: 770: 582: 579: 573: 564:You can help by 546: 545: 538: 336: 334: 333: 328: 326: 325: 319: 318: 313: 312: 305: 304: 296: 295: 288: 287: 279: 278: 252: 233: 218: 212: 210: 209: 204: 202: 201: 193: 192: 185: 184: 176: 175: 168: 167: 161: 160: 155: 154: 128: 109: 94: 87: 80: 76: 73: 67: 62:this article by 53:inline citations 40: 39: 32: 21: 6840: 6839: 6835: 6834: 6833: 6831: 6830: 6829: 6820:Heat conduction 6810: 6809: 6787: 6777: 6764: 6758: 6745: 6739: 6726: 6716: 6714:Further reading 6666: 6665: 6648: 6644: 6631: 6630: 6623: 6616: 6600:. p. 222. 6595: 6594: 6590: 6581: 6580: 6576: 6569: 6556: 6555: 6551: 6544: 6531: 6530: 6526: 6519: 6498: 6497: 6493: 6449: 6448: 6441: 6436:Wayback Machine 6426: 6422: 6417: 6413: 6408: 6386: 6359: 6346: 6340: 6339: 6311: 6297: 6282: 6272: 6240: 6234: 6233: 6199: 6184: 6174: 6154: 6135: 6119: 6095: 6089: 6088: 6044: 6025: 6016: 5994: 5979: 5952: 5933: 5932: 5909: 5908: 5881: 5875: 5874: 5852: 5846: 5845: 5820: 5807: 5791: 5772: 5766: 5765: 5743: 5730: 5714: 5695: 5689: 5688: 5654: 5638: 5626: 5625: 5597: 5581: 5569: 5568: 5543: 5537: 5536: 5514: 5508: 5507: 5473: 5451: 5430: 5429: 5403: 5402: 5365: 5359: 5358: 5337: 5336: 5289: 5288: 5252: 5251: 5217: 5209: 5170: 5162: 5138: 5132: 5131: 5105: 5104: 5083: 5082: 5037: 5029: 5020: 5016: 5006: 4985: 4984: 4967: 4935: 4922: 4911: 4910: 4889: 4888: 4860: 4854: 4853: 4833: 4788: 4775: 4771: 4734: 4728: 4727: 4685: 4672: 4671: 4660: 4650: 4649: 4626: 4620: 4619: 4578: 4558: 4530: 4519: 4518: 4499: 4462: 4449: 4436: 4415: 4410: 4409: 4404: 4399: 4363: 4357: 4354: 4347:needs expansion 4332: 4323: 4290: 4289: 4261: 4260: 4239: 4238: 4211: 4203: 4196: 4195: 4164: 4159: 4158: 4134: 4133: 4110: 4105: 4104: 4074: 4059: 4051: 4036: 4032: 4024: 4009: 4004: 4003: 3973: 3972: 3951: 3950: 3929: 3928: 3904: 3903: 3880: 3875: 3874: 3841: 3826: 3818: 3803: 3798: 3797: 3791:heat conduction 3783: 3710: 3679: 3648: 3625: 3601: 3575: 3574: 3530: 3504: 3499: 3498: 3455: 3432: 3427: 3426: 3419:(for a typical 3383: 3357: 3352: 3351: 3323: 3299: 3294: 3293: 3265: 3236: 3231: 3230: 3186: 3181: 3180: 3143: 3123: 3100: 3080: 3056: 3027: 2994: 2989: 2988: 2946: 2926: 2903: 2873: 2852: 2828: 2799: 2794: 2793: 2764: 2738: 2737: 2733:through it is: 2706: 2705: 2684: 2679: 2678: 2656: 2655: 2622: 2598: 2569: 2564: 2563: 2527: 2522: 2521: 2490: 2467: 2462: 2461: 2428: 2420: 2419: 2413: 2385: 2377: 2376: 2330: 2325: 2324: 2293: 2288: 2287: 2267: 2256: 2250: 2247: 2232: 2216: 2205: 2187: 2154: 2149: 2148: 2115: 2110: 2109: 2076: 2071: 2070: 2039: 2034: 2033: 2008: 2003: 2002: 1977: 1972: 1971: 1942: 1937: 1936: 1906: 1905: 1891: 1886: 1830: 1829: 1787: 1786: 1757: 1756: 1729: 1728: 1690: 1689: 1645: 1644: 1609: 1608: 1568: 1567: 1539: 1538: 1515: 1514: 1486: 1485: 1457: 1456: 1415: 1414: 1384: 1383: 1360: 1359: 1336: 1335: 1306: 1305: 1279: 1278: 1255: 1254: 1233: 1232: 1192: 1191: 1189:current density 1166: 1165: 1140: 1139: 1116: 1115: 1085: 1084: 1052: 1051: 1028: 1027: 1006: 1005: 974: 973: 950: 949: 926: 925: 902: 901: 871: 870: 847: 846: 823: 822: 799: 798: 757: 749:Main articles: 747: 731:degrees Celsius 707: 698:Thermal imaging 649:Food processing 639:Medical devices 618:Heat exchangers 583: 577: 574: 563: 547: 543: 536: 433:heat exchangers 379:thermal systems 306: 289: 272: 267: 266: 250: 231: 228: 186: 169: 148: 143: 142: 126: 107: 104: 88: 77: 71: 68: 58:Please help to 57: 41: 37: 30: 23: 22: 15: 12: 11: 5: 6838: 6836: 6828: 6827: 6822: 6812: 6811: 6808: 6807: 6800: 6795: 6786: 6785:External links 6783: 6782: 6781: 6775: 6762: 6756: 6743: 6737: 6715: 6712: 6711: 6710: 6699: 6664: 6663: 6643:978-0470646151 6642: 6621: 6614: 6588: 6574: 6567: 6549: 6542: 6524: 6517: 6491: 6462:(2): 149–168. 6439: 6420: 6410: 6409: 6407: 6404: 6403: 6402: 6397: 6392: 6385: 6382: 6381: 6380: 6366: 6362: 6358: 6353: 6349: 6323: 6320: 6317: 6314: 6309: 6304: 6300: 6295: 6289: 6285: 6281: 6278: 6275: 6269: 6263: 6260: 6257: 6254: 6250: 6247: 6243: 6227: 6226: 6211: 6206: 6202: 6197: 6191: 6187: 6183: 6180: 6177: 6172: 6167: 6164: 6161: 6157: 6153: 6148: 6145: 6142: 6138: 6134: 6131: 6128: 6125: 6122: 6116: 6111: 6104: 6101: 6079: 6078: 6073: 6071: 6057: 6054: 6051: 6047: 6043: 6039: 6032: 6028: 6024: 6019: 6015: 6012: 6006: 6001: 5997: 5992: 5986: 5982: 5978: 5975: 5972: 5965: 5962: 5959: 5955: 5951: 5946: 5943: 5940: 5936: 5929: 5926: 5923: 5920: 5917: 5888: 5884: 5859: 5855: 5842: 5841: 5827: 5823: 5819: 5814: 5810: 5806: 5803: 5798: 5794: 5790: 5785: 5782: 5779: 5775: 5750: 5746: 5742: 5737: 5733: 5729: 5726: 5721: 5717: 5713: 5708: 5705: 5702: 5698: 5682: 5681: 5667: 5664: 5661: 5657: 5653: 5650: 5645: 5641: 5637: 5634: 5610: 5607: 5604: 5600: 5596: 5593: 5588: 5584: 5580: 5577: 5550: 5546: 5521: 5517: 5502: 5501: 5496: 5494: 5480: 5476: 5472: 5469: 5466: 5463: 5458: 5454: 5450: 5447: 5444: 5441: 5438: 5411: 5372: 5368: 5345: 5323: 5320: 5317: 5313: 5309: 5306: 5303: 5300: 5297: 5275: 5272: 5269: 5266: 5263: 5260: 5246: 5245: 5240: 5238: 5223: 5220: 5215: 5212: 5206: 5203: 5200: 5197: 5194: 5191: 5188: 5185: 5182: 5176: 5173: 5168: 5165: 5159: 5156: 5153: 5150: 5145: 5141: 5113: 5091: 5077: 5076: 5071: 5069: 5057: 5054: 5050: 5043: 5040: 5035: 5032: 5026: 5023: 5019: 5012: 5009: 5005: 4998: 4995: 4966: 4965:Radial systems 4963: 4948: 4942: 4938: 4934: 4929: 4925: 4920: 4897: 4873: 4870: 4867: 4863: 4832: 4829: 4826: 4825: 4820: 4818: 4803: 4800: 4795: 4791: 4787: 4782: 4778: 4774: 4770: 4765: 4758: 4755: 4752: 4749: 4744: 4741: 4737: 4717: 4716: 4711: 4709: 4692: 4688: 4684: 4679: 4675: 4667: 4663: 4657: 4653: 4646: 4640: 4637: 4634: 4629: 4609: 4608: 4603: 4601: 4585: 4581: 4577: 4572: 4565: 4561: 4557: 4552: 4544: 4541: 4538: 4533: 4529: 4498: 4495: 4483: 4480: 4477: 4474: 4469: 4465: 4461: 4456: 4452: 4448: 4443: 4439: 4435: 4429: 4426: 4423: 4418: 4403: 4400: 4398: 4395: 4365: 4364: 4344: 4342: 4331: 4328: 4322: 4319: 4318: 4317: 4297: 4287: 4271: 4268: 4258: 4246: 4236: 4217: 4214: 4209: 4206: 4193: 4171: 4167: 4156: 4144: 4141: 4131: 4117: 4113: 4098: 4097: 4084: 4080: 4077: 4071: 4065: 4062: 4057: 4054: 4043: 4039: 4035: 4030: 4027: 4021: 4016: 4012: 3993: 3992: 3980: 3970: 3958: 3948: 3936: 3926: 3914: 3911: 3901: 3887: 3883: 3868: 3867: 3854: 3850: 3847: 3844: 3838: 3832: 3829: 3824: 3821: 3815: 3810: 3806: 3782: 3779: 3776: 3775: 3763: 3762: 3743: 3740: 3728: 3717: 3709: 3706: 3697: 3686: 3678: 3675: 3666: 3655: 3647: 3642: 3632: 3624: 3621: 3618: 3608: 3600: 3594: 3588: 3585: 3568: 3567: 3548: 3537: 3529: 3526: 3519: 3516: 3511: 3507: 3496: 3473: 3462: 3454: 3451: 3444: 3439: 3435: 3424: 3401: 3390: 3382: 3379: 3372: 3369: 3364: 3360: 3349: 3330: 3322: 3319: 3313: 3310: 3307: 3302: 3291: 3272: 3264: 3261: 3254: 3251: 3248: 3243: 3239: 3209: 3206: 3203: 3195: 3192: 3177: 3176: 3158: 3155: 3150: 3146: 3142: 3135: 3130: 3126: 3122: 3115: 3112: 3107: 3103: 3097: 3091: 3088: 3083: 3079: 3076: 3070: 3067: 3064: 3059: 3055: 3052: 3045: 3042: 3039: 3034: 3030: 3023: 3017: 3014: 3011: 3003: 3000: 2982: 2981: 2968: 2961: 2958: 2953: 2949: 2945: 2938: 2933: 2929: 2925: 2918: 2915: 2910: 2906: 2902: 2896: 2893: 2890: 2882: 2879: 2872: 2869: 2863: 2860: 2855: 2851: 2848: 2842: 2839: 2836: 2831: 2827: 2824: 2817: 2814: 2811: 2806: 2802: 2787: 2786: 2771: 2767: 2760: 2757: 2751: 2748: 2745: 2719: 2716: 2691: 2687: 2666: 2663: 2652: 2651: 2639: 2633: 2630: 2625: 2621: 2618: 2612: 2609: 2606: 2601: 2597: 2594: 2587: 2584: 2581: 2576: 2572: 2539: 2534: 2530: 2518: 2517: 2502: 2497: 2493: 2489: 2482: 2479: 2474: 2470: 2439: 2436: 2431: 2427: 2411: 2396: 2393: 2388: 2384: 2348: 2345: 2342: 2337: 2333: 2308: 2305: 2300: 2296: 2278: 2277: 2269: 2268: 2219: 2217: 2210: 2204: 2201: 2186: 2185: 2169: 2166: 2161: 2157: 2146: 2130: 2127: 2122: 2118: 2107: 2091: 2088: 2083: 2079: 2068: 2053: 2050: 2047: 2042: 2031: 2016: 2011: 2000: 1985: 1980: 1969: 1968:in the device. 1950: 1945: 1934: 1919: 1916: 1902: 1890: 1887: 1885: 1882: 1879: 1878: 1867: 1863: 1859: 1856: 1853: 1849: 1845: 1842: 1838: 1824: 1813: 1809: 1805: 1802: 1799: 1795: 1781: 1770: 1767: 1764: 1753: 1742: 1739: 1736: 1725: 1721: 1720: 1709: 1706: 1703: 1700: 1697: 1684: 1673: 1667: 1664: 1658: 1655: 1652: 1639: 1628: 1625: 1622: 1619: 1616: 1603: 1592: 1588: 1584: 1581: 1578: 1575: 1562: 1558: 1557: 1546: 1533: 1522: 1509: 1504: 1493: 1480: 1476: 1475: 1464: 1451: 1446: 1441: 1430: 1426: 1422: 1409: 1403: 1402: 1391: 1378: 1367: 1354: 1343: 1330: 1319: 1316: 1313: 1302: 1298: 1297: 1286: 1273: 1262: 1251: 1240: 1227: 1217: 1213: 1212: 1200: 1186: 1174: 1160: 1148: 1134: 1123: 1110: 1104: 1103: 1092: 1079: 1065: 1062: 1046: 1035: 1024: 1013: 999: 993: 992: 981: 968: 957: 944: 933: 920: 909: 896: 890: 889: 878: 865: 854: 841: 830: 817: 806: 793: 787: 786: 783: 780: 777: 774: 746: 743: 706: 703: 702: 701: 695: 689: 683: 677: 674: 668: 662: 656: 653:pasteurization 646: 636: 633: 627: 621: 615: 609: 603: 597: 585: 584: 550: 548: 541: 535: 532: 528:imperial units 352:thermodynamics 338: 337: 324: 317: 311: 303: 300: 294: 286: 283: 277: 264: 258: 257: 254: 245: 244: 241: 235: 234: 229: 227:Common symbols 226: 223: 222: 214: 213: 200: 197: 191: 183: 180: 174: 166: 159: 153: 140: 134: 133: 130: 121: 120: 117: 111: 110: 105: 103:Common symbols 102: 99: 98: 90: 89: 44: 42: 35: 28: 24: 14: 13: 10: 9: 6: 4: 3: 2: 6837: 6826: 6823: 6821: 6818: 6817: 6815: 6805: 6801: 6799: 6796: 6793: 6789: 6788: 6784: 6778: 6772: 6768: 6763: 6759: 6753: 6750:. CRC Press. 6749: 6744: 6740: 6734: 6730: 6725: 6724: 6723: 6721: 6713: 6708: 6704: 6700: 6697: 6693: 6689: 6685: 6681: 6680: 6679: 6678: 6674: 6671: 6659: 6653: 6645: 6639: 6635: 6628: 6626: 6622: 6617: 6611: 6607: 6603: 6599: 6592: 6589: 6585:. 2013-02-22. 6584: 6578: 6575: 6570: 6564: 6560: 6553: 6550: 6545: 6539: 6535: 6528: 6525: 6520: 6514: 6510: 6505: 6504: 6495: 6492: 6487: 6483: 6478: 6473: 6469: 6465: 6461: 6457: 6453: 6446: 6444: 6440: 6437: 6433: 6429: 6424: 6421: 6415: 6412: 6405: 6401: 6398: 6396: 6393: 6391: 6388: 6387: 6383: 6364: 6360: 6356: 6351: 6347: 6321: 6318: 6315: 6312: 6302: 6298: 6293: 6287: 6283: 6276: 6273: 6267: 6248: 6245: 6241: 6232: 6231: 6230: 6204: 6200: 6195: 6189: 6185: 6178: 6175: 6165: 6162: 6159: 6155: 6151: 6146: 6143: 6140: 6136: 6129: 6126: 6123: 6120: 6114: 6109: 6102: 6099: 6087: 6086: 6085: 6077: 6074: 6072: 6055: 6052: 6049: 6045: 6041: 6037: 6030: 6026: 6022: 6017: 6013: 6010: 5999: 5995: 5990: 5984: 5980: 5973: 5970: 5963: 5960: 5957: 5953: 5949: 5944: 5941: 5938: 5934: 5927: 5921: 5915: 5907: 5906: 5903: 5886: 5882: 5857: 5853: 5825: 5821: 5817: 5812: 5808: 5804: 5801: 5796: 5792: 5788: 5783: 5780: 5777: 5773: 5764:and 5748: 5744: 5740: 5735: 5731: 5727: 5724: 5719: 5715: 5711: 5706: 5703: 5700: 5696: 5687: 5686: 5685: 5665: 5662: 5659: 5655: 5651: 5643: 5639: 5632: 5624:and 5608: 5605: 5602: 5598: 5594: 5586: 5582: 5575: 5567: 5566: 5565: 5548: 5544: 5519: 5515: 5500: 5497: 5495: 5478: 5474: 5470: 5467: 5464: 5461: 5456: 5452: 5448: 5442: 5436: 5428: 5427: 5424: 5409: 5400: 5391: 5387: 5370: 5366: 5343: 5318: 5315: 5311: 5307: 5304: 5298: 5295: 5273: 5270: 5267: 5264: 5261: 5258: 5244: 5241: 5239: 5221: 5218: 5213: 5210: 5201: 5198: 5195: 5192: 5186: 5183: 5180: 5174: 5171: 5166: 5163: 5157: 5154: 5151: 5148: 5143: 5139: 5130: 5129: 5126: 5111: 5089: 5075: 5072: 5070: 5055: 5052: 5048: 5041: 5038: 5033: 5030: 5024: 5021: 5017: 5010: 5007: 5003: 4996: 4993: 4983: 4982: 4979: 4977: 4976:Fourier's law 4972: 4964: 4962: 4940: 4936: 4932: 4927: 4923: 4895: 4871: 4868: 4865: 4861: 4851: 4847: 4837: 4830: 4824: 4821: 4819: 4801: 4793: 4789: 4785: 4780: 4776: 4768: 4763: 4742: 4739: 4735: 4726: 4725: 4722: 4715: 4712: 4710: 4690: 4686: 4682: 4677: 4673: 4665: 4661: 4655: 4651: 4644: 4627: 4618: 4617: 4614: 4607: 4604: 4602: 4583: 4579: 4575: 4570: 4563: 4559: 4555: 4550: 4531: 4527: 4517: 4516: 4513: 4510: 4503: 4496: 4494: 4481: 4478: 4475: 4472: 4467: 4463: 4459: 4454: 4450: 4446: 4441: 4437: 4433: 4416: 4407: 4401: 4396: 4394: 4390: 4388: 4383: 4381: 4377: 4373: 4361: 4352: 4348: 4345:This section 4343: 4340: 4336: 4335: 4329: 4327: 4320: 4315: 4311: 4295: 4288: 4285: 4269: 4259: 4244: 4237: 4234: 4215: 4207: 4194: 4191: 4187: 4169: 4165: 4157: 4142: 4132: 4115: 4111: 4103: 4102: 4101: 4082: 4078: 4069: 4063: 4055: 4041: 4037: 4033: 4028: 4019: 4014: 4010: 4002: 4001: 4000: 3998: 3978: 3971: 3956: 3949: 3934: 3927: 3912: 3902: 3885: 3881: 3873: 3872: 3871: 3852: 3848: 3845: 3836: 3830: 3827: 3822: 3813: 3808: 3804: 3796: 3795: 3794: 3792: 3788: 3787:Fourier's Law 3774: 3770: 3768: 3741: 3738: 3726: 3715: 3707: 3704: 3695: 3684: 3676: 3673: 3664: 3653: 3645: 3630: 3622: 3616: 3606: 3598: 3592: 3586: 3583: 3573: 3572: 3571: 3546: 3535: 3527: 3524: 3509: 3505: 3497: 3494: 3471: 3460: 3452: 3449: 3437: 3433: 3425: 3422: 3399: 3388: 3380: 3377: 3362: 3358: 3350: 3328: 3320: 3317: 3300: 3292: 3270: 3262: 3259: 3241: 3237: 3229: 3228: 3227: 3224: 3193: 3190: 3148: 3144: 3140: 3128: 3124: 3120: 3105: 3101: 3081: 3074: 3057: 3050: 3032: 3028: 3021: 3001: 2998: 2987: 2986: 2985: 2951: 2947: 2943: 2931: 2927: 2923: 2908: 2904: 2880: 2877: 2870: 2853: 2846: 2829: 2822: 2804: 2800: 2792: 2791: 2790: 2769: 2765: 2758: 2755: 2749: 2746: 2736: 2735: 2734: 2717: 2714: 2689: 2685: 2664: 2623: 2616: 2599: 2592: 2574: 2570: 2561: 2560: 2559: 2557: 2532: 2528: 2495: 2491: 2487: 2472: 2468: 2459: 2458: 2457: 2454: 2429: 2415: 2386: 2374: 2370: 2366: 2335: 2331: 2298: 2294: 2285: 2280: 2279: 2275: 2274: 2265: 2262: 2254: 2244: 2240: 2236: 2230: 2229: 2225: 2220:This section 2218: 2214: 2209: 2208: 2202: 2200: 2198: 2193: 2159: 2155: 2147: 2120: 2116: 2108: 2081: 2077: 2069: 2040: 2032: 2009: 2001: 1978: 1970: 1967: 1943: 1935: 1917: 1914: 1904: 1903: 1900: 1895: 1888: 1883: 1865: 1857: 1854: 1851: 1843: 1840: 1828: 1825: 1811: 1803: 1800: 1797: 1785: 1784:Fourier's law 1782: 1768: 1765: 1762: 1754: 1740: 1737: 1734: 1726: 1723: 1722: 1707: 1704: 1701: 1698: 1688: 1685: 1671: 1665: 1662: 1656: 1653: 1643: 1640: 1626: 1623: 1620: 1617: 1607: 1604: 1590: 1586: 1582: 1579: 1576: 1566: 1563: 1560: 1559: 1544: 1537: 1534: 1520: 1513: 1510: 1508: 1505: 1491: 1484: 1481: 1479:conductivity 1478: 1477: 1462: 1455: 1452: 1450: 1447: 1445: 1442: 1428: 1424: 1420: 1413: 1410: 1408: 1405: 1404: 1389: 1382: 1379: 1365: 1358: 1355: 1341: 1334: 1331: 1317: 1314: 1311: 1303: 1300: 1299: 1284: 1277: 1274: 1260: 1252: 1238: 1231: 1228: 1225: 1221: 1218: 1215: 1214: 1190: 1187: 1164: 1161: 1138: 1135: 1121: 1114: 1111: 1109: 1106: 1105: 1090: 1083: 1080: 1063: 1060: 1050: 1047: 1033: 1025: 1011: 1004: 1000: 998: 995: 994: 979: 972: 969: 955: 948: 945: 931: 924: 921: 907: 900: 897: 895: 892: 891: 876: 869: 866: 852: 845: 842: 828: 821: 818: 804: 797: 794: 792: 789: 788: 784: 781: 778: 775: 772: 771: 768: 766: 762: 756: 752: 744: 742: 738: 736: 732: 728: 724: 720: 716: 712: 704: 699: 696: 693: 690: 687: 686:Manufacturing 684: 681: 678: 675: 672: 669: 666: 663: 660: 657: 654: 650: 647: 644: 640: 637: 634: 631: 628: 625: 622: 619: 616: 613: 610: 607: 604: 601: 598: 595: 592: 591: 590: 581: 572:is available. 571: 567: 561: 560: 556: 551:This section 549: 540: 539: 533: 531: 529: 525: 521: 517: 514: 510: 506: 502: 500: 495: 491: 489: 485: 481: 477: 473: 469: 463: 461: 457: 453: 449: 445: 440: 438: 434: 430: 426: 422: 418: 414: 412: 408: 404: 400: 396: 392: 388: 384: 380: 376: 375:thermal shock 372: 368: 364: 360: 356: 353: 349: 345: 344:heat transfer 315: 301: 298: 284: 281: 265: 263: 259: 255: 253: 246: 242: 240: 236: 230: 224: 219: 198: 195: 181: 178: 157: 141: 139: 135: 131: 129: 122: 118: 116: 112: 106: 100: 95: 86: 83: 75: 65: 61: 55: 54: 48: 43: 34: 33: 27: 19: 6766: 6747: 6728: 6717: 6672: 6669: 6667: 6633: 6597: 6591: 6577: 6558: 6552: 6533: 6527: 6502: 6494: 6459: 6455: 6423: 6414: 6228: 6082: 6075: 5844:Solving for 5843: 5683: 5505: 5498: 5423:is constant 5396: 5249: 5242: 5080: 5073: 4968: 4842: 4822: 4720: 4713: 4612: 4605: 4511: 4508: 4408: 4405: 4391: 4384: 4368: 4358:January 2015 4355: 4351:adding to it 4346: 4324: 4099: 3994: 3869: 3784: 3771: 3764: 3569: 3225: 3178: 2983: 2788: 2653: 2519: 2455: 2416: 2283: 2281: 2257: 2251:January 2015 2248: 2233:Please help 2221: 2194: 2192:capacitors. 2190: 1301:conductance 1108:flux density 899:displacement 758: 739: 734: 708: 680:Solar energy 588: 578:October 2023 575: 570:Editing help 552: 505:square metre 498: 493: 492: 472:conductivity 464: 447: 443: 442:Conversely, 441: 420: 416: 415: 367:heat current 358: 354: 341: 239:SI unit 115:SI unit 78: 72:January 2015 69: 50: 26: 3767:reliability 1565:Hooke's law 1412:flexibility 1407:resistivity 1220:flexibility 1216:resistance 947:temperature 765:Hooke's law 711:temperature 513:square foot 468:resistivity 452:temperature 391:electronics 64:introducing 6814:Categories 6675:2020. DOI: 6406:References 6338:such that 4846:isothermal 1226:defined) 1026:flow rate 630:Cryogenics 460:heat sinks 373:, prevent 47:references 6652:cite book 6486:121803741 6316:π 6277:⁡ 6179:⁡ 6152:− 6124:π 6103:˙ 6014:⁡ 5974:⁡ 5950:− 5805:⁡ 5728:⁡ 5465:⁡ 5268:π 5196:π 5184:− 5152:− 4933:− 4850:adiabatic 4267:Δ 4213:Δ 4205:Δ 4186:heat flux 4166:ϕ 4140:Δ 4116:θ 4076:Δ 4061:Δ 4053:Δ 4038:ϕ 4026:Δ 4015:θ 3997:heat flux 3910:Δ 3886:θ 3843:Δ 3820:Δ 3809:θ 3716:∘ 3685:∘ 3654:∘ 3631:∘ 3617:− 3607:∘ 3587:˙ 3536:∘ 3510:θ 3493:elastomer 3461:∘ 3438:θ 3389:∘ 3363:θ 3329:∘ 3271:∘ 3194:˙ 3149:θ 3129:θ 3106:θ 3078:Δ 3051:− 3002:˙ 2952:θ 2932:θ 2909:θ 2881:˙ 2850:Δ 2823:− 2770:θ 2759:˙ 2744:Δ 2718:˙ 2690:θ 2662:Δ 2620:Δ 2593:− 2533:θ 2496:θ 2473:θ 2426:Δ 2383:Δ 2373:heat sink 2365:heat sink 2299:θ 2286:(symbol: 2222:does not 2197:heat sink 2160:θ 2121:θ 2082:θ 1918:˙ 1899:heat sink 1862:∇ 1858:σ 1855:− 1844:σ 1827:Ohm's law 1808:∇ 1801:− 1696:Δ 1687:Ohm's law 1666:˙ 1651:Δ 1615:Δ 1574:Δ 1545:σ 1483:stiffness 1463:ρ 1163:heat flux 1122:σ 1064:˙ 971:potential 894:potential 761:Ohm's law 624:Aerospace 323:Θ 299:− 282:− 262:Dimension 196:− 190:Θ 179:− 138:Dimension 6432:Archived 6384:See also 3423:package) 2276:Example 1224:rheology 1137:velocity 1001:load or 923:pressure 791:quantity 782:thermal 612:Cookware 509:SI units 256:kgâ‹…mâ‹…sâ‹…K 132:kgâ‹…mâ‹…sâ‹…K 6707:Ixys RF 6696:Germany 6464:Bibcode 4308:is the 4184:is the 4100:where: 3870:where: 2243:removed 2228:sources 1964:is the 1082:current 796:impulse 60:improve 6773:  6754:  6735:  6692:Munich 6640:  6612:  6565:  6540:  6515:  6511:–461. 6484:  5250:Where 5081:Where 3745:  3712:  3681:  3650:  3627:  3603:  3532:  3457:  3421:TO-220 3385:  3325:  3267:  2520:where 1113:stress 868:charge 820:volume 725:. The 553:is in 501:-value 429:kelvin 405:, and 393:, and 350:, and 49:, but 6482:S2CID 4372:JEDEC 3785:From 1003:force 773:type 559:prose 520:hours 480:shape 425:watts 6771:ISBN 6752:ISBN 6733:ISBN 6658:link 6638:ISBN 6610:ISBN 6563:ISBN 6538:ISBN 6513:ISBN 6357:> 5873:and 5535:and 4192:·m), 3789:for 3742:18.6 2226:any 2224:cite 1755:... 1727:... 1304:... 997:flux 844:heat 753:and 719:time 715:heat 555:list 522:per 478:and 476:size 427:per 363:heat 357:and 6602:doi 6509:460 6472:doi 6076:(7) 5499:(6) 5243:(5) 5074:(4) 4823:(3) 4714:(2) 4606:(1) 4353:. 3677:0.1 3646:1.5 3599:125 3453:0.1 3381:1.5 3263:125 2237:by 511:or 470:or 342:In 248:In 124:In 6816:: 6705:. 6694:, 6690:, 6686:. 6654:}} 6650:{{ 6624:^ 6608:. 6480:. 6470:. 6460:29 6458:. 6454:. 6442:^ 6430:. 6274:ln 6176:ln 6011:ln 5971:ln 5802:ln 5725:ln 5462:ln 4961:. 4382:. 3769:. 3623:21 3321:21 2412:HS 2199:. 727:SI 435:, 413:. 401:, 389:, 385:, 346:, 6779:. 6760:. 6741:. 6698:. 6660:) 6646:. 6618:. 6604:: 6571:. 6546:. 6521:. 6488:. 6474:: 6466:: 6365:1 6361:r 6352:2 6348:r 6322:k 6319:L 6313:2 6308:) 6303:1 6299:r 6294:/ 6288:2 6284:r 6280:( 6268:= 6262:d 6259:n 6256:o 6253:c 6249:, 6246:t 6242:R 6210:) 6205:1 6201:r 6196:/ 6190:2 6186:r 6182:( 6171:) 6166:2 6163:, 6160:s 6156:T 6147:1 6144:, 6141:s 6137:T 6133:( 6130:k 6127:L 6121:2 6115:= 6110:r 6100:Q 6056:2 6053:, 6050:s 6046:T 6042:+ 6038:) 6031:2 6027:r 6023:r 6018:( 6005:) 6000:2 5996:r 5991:/ 5985:1 5981:r 5977:( 5964:2 5961:, 5958:s 5954:T 5945:1 5942:, 5939:s 5935:T 5928:= 5925:) 5922:r 5919:( 5916:T 5887:2 5883:C 5858:1 5854:C 5826:2 5822:C 5818:+ 5813:2 5809:r 5797:1 5793:C 5789:= 5784:2 5781:, 5778:s 5774:T 5749:2 5745:C 5741:+ 5736:1 5732:r 5720:1 5716:C 5712:= 5707:1 5704:, 5701:s 5697:T 5666:2 5663:, 5660:s 5656:T 5652:= 5649:) 5644:2 5640:r 5636:( 5633:T 5609:1 5606:, 5603:s 5599:T 5595:= 5592:) 5587:1 5583:r 5579:( 5576:T 5549:2 5545:C 5520:1 5516:C 5479:2 5475:C 5471:+ 5468:r 5457:1 5453:C 5449:= 5446:) 5443:r 5440:( 5437:T 5410:k 5371:r 5367:q 5344:r 5322:) 5319:r 5316:d 5312:/ 5308:T 5305:d 5302:( 5299:r 5296:k 5274:L 5271:r 5265:2 5262:= 5259:A 5222:r 5219:d 5214:T 5211:d 5205:) 5202:L 5199:r 5193:2 5190:( 5187:k 5181:= 5175:r 5172:d 5167:T 5164:d 5158:A 5155:k 5149:= 5144:r 5140:q 5112:k 5090:k 5056:0 5053:= 5049:) 5042:r 5039:d 5034:T 5031:d 5025:r 5022:k 5018:( 5011:r 5008:d 5004:d 4997:r 4994:1 4947:| 4941:g 4937:k 4928:f 4924:k 4919:| 4896:q 4872:t 4869:o 4866:t 4862:R 4802:A 4799:) 4794:c 4790:k 4786:+ 4781:b 4777:k 4773:( 4769:L 4764:= 4757:d 4754:n 4751:o 4748:c 4743:, 4740:t 4736:R 4691:C 4687:R 4683:+ 4678:B 4674:R 4666:C 4662:R 4656:B 4652:R 4645:= 4639:t 4636:o 4633:t 4628:R 4584:C 4580:R 4576:1 4571:+ 4564:B 4560:R 4556:1 4551:= 4543:t 4540:o 4537:t 4532:R 4528:1 4482:. 4479:. 4476:. 4473:+ 4468:C 4464:R 4460:+ 4455:B 4451:R 4447:+ 4442:A 4438:R 4434:= 4428:t 4425:o 4422:t 4417:R 4360:) 4356:( 4314:W 4312:( 4296:q 4284:K 4270:T 4245:A 4233:K 4216:x 4208:T 4190:W 4170:q 4143:x 4112:R 4083:q 4079:T 4070:= 4064:x 4056:T 4042:q 4034:A 4029:x 4020:= 4011:R 3979:A 3957:r 3935:k 3913:x 3882:R 3853:A 3849:r 3846:x 3837:= 3831:k 3828:A 3823:x 3814:= 3805:R 3749:W 3739:= 3732:W 3727:/ 3722:C 3708:4 3705:+ 3701:W 3696:/ 3691:C 3674:+ 3670:W 3665:/ 3660:C 3641:) 3637:C 3620:( 3613:C 3593:= 3584:Q 3552:W 3547:/ 3542:C 3528:4 3525:= 3518:A 3515:H 3506:R 3477:W 3472:/ 3467:C 3450:= 3443:B 3434:R 3405:W 3400:/ 3395:C 3378:= 3371:C 3368:J 3359:R 3335:C 3318:= 3312:b 3309:m 3306:a 3301:T 3277:C 3260:= 3253:x 3250:a 3247:m 3242:J 3238:T 3208:x 3205:a 3202:m 3191:Q 3157:A 3154:H 3145:R 3141:+ 3134:B 3125:R 3121:+ 3114:C 3111:J 3102:R 3096:) 3090:S 3087:H 3082:T 3075:+ 3069:b 3066:m 3063:a 3058:T 3054:( 3044:x 3041:a 3038:m 3033:J 3029:T 3022:= 3016:x 3013:a 3010:m 2999:Q 2980:, 2967:) 2960:A 2957:H 2948:R 2944:+ 2937:B 2928:R 2924:+ 2917:C 2914:J 2905:R 2901:( 2895:x 2892:a 2889:m 2878:Q 2871:= 2868:) 2862:S 2859:H 2854:T 2847:+ 2841:b 2838:m 2835:a 2830:T 2826:( 2816:x 2813:a 2810:m 2805:J 2801:T 2785:. 2766:R 2756:Q 2750:= 2747:T 2715:Q 2686:R 2665:T 2650:. 2638:) 2632:S 2629:H 2624:T 2617:+ 2611:b 2608:m 2605:a 2600:T 2596:( 2586:x 2583:a 2580:m 2575:J 2571:T 2538:B 2529:R 2501:B 2492:R 2488:+ 2481:C 2478:J 2469:R 2438:S 2435:H 2430:T 2395:S 2392:H 2387:T 2347:x 2344:a 2341:m 2336:J 2332:T 2307:C 2304:J 2295:R 2264:) 2258:( 2253:) 2249:( 2245:. 2231:. 2168:A 2165:H 2156:R 2129:H 2126:C 2117:R 2090:C 2087:J 2078:R 2052:b 2049:m 2046:a 2041:T 2015:H 2010:T 1984:C 1979:T 1949:J 1944:T 1915:Q 1901:: 1866:V 1852:= 1848:E 1841:= 1837:J 1812:T 1804:k 1798:= 1794:q 1769:. 1766:. 1763:. 1741:. 1738:. 1735:. 1708:R 1705:I 1702:= 1699:V 1672:R 1663:Q 1657:= 1654:T 1627:R 1624:Q 1621:= 1618:P 1591:k 1587:/ 1583:F 1580:= 1577:X 1521:k 1492:k 1429:k 1425:/ 1421:1 1390:G 1366:G 1342:G 1318:. 1315:. 1312:. 1285:R 1261:R 1239:R 1222:( 1199:j 1173:q 1147:v 1091:I 1061:Q 1034:Q 1012:F 980:V 956:T 932:P 908:X 877:q 853:Q 829:V 805:J 735:T 580:) 576:( 562:. 518:– 499:R 496:( 448:R 446:( 421:G 419:( 316:3 310:T 302:1 293:M 285:2 276:L 232:R 199:1 182:3 173:T 165:M 158:2 152:L 108:G 85:) 79:( 74:) 70:( 56:. 20:)

Index

Thermal resistance in electronics
references
inline citations
improve
introducing
Learn how and when to remove this message
SI unit
SI base units
Dimension
SI unit
SI base units
Dimension
heat transfer
thermal engineering
thermodynamics
heat
heat current
temperature gradient
thermal shock
thermal systems
materials science
mechanical engineering
electronics
energy management
temperature control
thermal insulation
thermal management
electronic devices
watts
kelvin

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