3589:) at some rpm N. On decreasing the flow-rate at same rpm along the characteristic curve by partial closing of the valve, the pressure in the pipe increases which will be taken care by increase in input pressure at the compressor. Further increase in pressure till point P (surge point), compressor pressure will increase. Further moving towards left keeping rpm constant, pressure in pipe will increase but compressor pressure will decrease leading to back air-flow towards the compressor. Due to this back flow, pressure in pipe will decrease because this unequal pressure condition cannot stay for a long period of time. Though valve position is set for lower flow rate say point G but compressor will work according to normal stable operation point say E, so path E-F-P-G-E will be followed leading to breakdown of flow, hence pressure in the compressor falls further to point H(
227:
pressure. The relative kinetic head in the energy equation is a term that exists only because of the rotation of the rotor. The rotor reduces the relative kinetic head of the fluid and adds it to the absolute kinetic head of the fluid i.e., the impact of the rotor on the fluid particles increases their velocity (absolute) and thereby reduces the relative velocity between the fluid and the rotor. In short, the rotor increases the absolute velocity of the fluid and the stator converts this into pressure rise. Designing the rotor passage with a diffusing capability can produce a pressure rise in addition to its normal functioning. This produces greater pressure rise per stage which constitutes a stator and a rotor together. This is the reaction principle in
3706:, for example, recognized that a turbine which produced work by virtue of a fluid's static pressure (i.e. a reaction turbine) could have its action reversed to act as an air compressor, calling it a turbo compressor or pump. His rotor and stator blading described in one of his patents had little or no camber although in some cases the blade design was based on propeller theory. The machines, driven by steam turbines, were used for industrial purposes such as supplying air to blast furnaces. Parsons supplied the first commercial axial flow compressor for use in a lead smelter in 1901. Parsons' machines had low efficiencies, later attributed to blade stall, and were soon replaced with more efficient centrifugal compressors.
249:
and pressure surge respectively). Thus, a practical limit on the number of stages, and the overall pressure ratio, comes from the interaction of the different stages when required to work away from the design conditions. These “off-design” conditions can be mitigated to a certain extent by providing some flexibility in the compressor. This is achieved normally through the use of adjustable stators or with valves that can bleed fluid from the main flow between stages (inter-stage bleed). Modern jet engines use a series of compressors, running at different speeds; to supply air at around 40:1 pressure ratio for combustion with sufficient flexibility for all flight conditions.
245:
temperature (Tstage) to each stage must increase progressively through the compressor and the ratio (Delta T)/(Tstage) entry must decrease, thus implying a progressive reduction in stage pressure ratio through the unit. Hence the rear stage develops a significantly lower pressure ratio than the first stage. Higher stage pressure ratios are also possible if the relative velocity between fluid and rotors is supersonic, but this is achieved at the expense of efficiency and operability. Such compressors, with stage pressure ratios of over 2, are only used where minimizing the compressor size, weight or complexity is critical, such as in military jets.
2773:
2679:
2516:
3915:
194:
258:
1962:
3523:
3867:
3543:
pressure. When the compressor is operating as part of a complete gas turbine engine, as opposed to on a test rig, a higher delivery pressure at a particular speed can be caused momentarily by burning too-great a step-jump in fuel which causes a momentary blockage until the compressor increases to the speed which goes with the new fuel flow and the surging stops.
2511:{\displaystyle {\begin{aligned}R&={\frac {h_{2}-h_{1}}{h_{02}-h_{01}}}\\P&={\dot {m}}c_{p}\left(T_{2}+{\frac {V_{2}^{2}}{2c_{p}}}-\left\right)\\P&={\dot {m}}\left(h_{2}-h_{1}+\left\right)\\h_{2}-h_{1}&={\frac {V_{r1}^{2}}{2}}-{\frac {V_{r2}^{2}}{2}}\\T_{2}-T_{1}&={\frac {V_{r1}^{2}}{2c_{p}}}-{\frac {V_{r2}^{2}}{2c_{p}}}\end{aligned}}}
209:
pair of one row of rotating airfoils and the next row of stationary airfoils is called a stage. The rotating airfoils, also known as blades or rotors, accelerate the fluid in both the axial and circumferential directions. The stationary airfoils, also known as vanes or stators, convert the increased kinetic energy into static pressure through
1726:
2692:
stall or surge, would result. The parameter used the rotor speed, Helmholtz resonator frequency of the system and an "effective length" of the compressor duct. It had a critical value which predicted either rotating stall or surge where the slope of pressure ratio against flow changed from negative to positive.
3939:, resulted in increased efficiency. Further increases in efficiency may be realised by adding a third spool, but in practice the added complexity increases maintenance costs to the point of negating any economic benefit. That said, there are several three-spool engines in use, perhaps the most famous being the
3673:
In a rotor with blades moving say towards right. Let some blades receives flow at higher incidence, this blade will stop positively. It creates obstruction in the passage between the blade to its left and itself. Thus the left blade will receive the flow at higher incidence and the blade to its right
3629:
Stalling is an important phenomenon that affects the performance of the compressor. An analysis is made of rotating stall in compressors of many stages, finding conditions under which a flow distortion can occur which is steady in a traveling reference frame, even though upstream total and downstream
248:
The airfoil profiles are optimized and matched for specific velocities and turning. Although compressors can be run at other conditions with different flows, speeds, or pressure ratios, this can result in an efficiency penalty or even a partial or complete breakdown in flow (known as compressor stall
3674:
with decreased incidence. The left blade will experience more stall while the blade to its right will experience lesser stall. Towards the right stalling will decrease whereas it will increase towards its left. Movement of the rotating stall can be observed depending upon the chosen reference frame.
3654:
In a multi-stage compressor, at the high pressure stages, axial velocity is very small. Stalling value decreases with a small deviation from the design point causing stall near the hub and tip regions whose size increases with decreasing flow rates. They grow larger at very low flow rate and affect
3542:
The following explanation for surging refers to running a compressor at a constant speed on a rig and gradually reducing the exit area by closing a valve. What happens, i.e. crossing the surge line, is caused by the compressor trying to deliver air, still running at the same speed, to a higher exit
2691:
Greitzer used a
Helmholtz resonator type of compression system model to predict the transient response of a compression system after a small perturbation superimposed on a steady operating condition. He found a non-dimensional parameter which predicted which mode of compressor instability, rotating
239:
The increase in pressure produced by a single stage is limited by the relative velocity between the rotor and the fluid, and the turning and diffusion capabilities of the airfoils. A typical stage in a commercial compressor will produce a pressure increase of between 15% and 60% (pressure ratios of
226:
As the fluid enters and leaves in the axial direction, the centrifugal component in the energy equation does not come into play. Here the compression is fully based on diffusing action of the passages. The diffusing action in the stator converts the absolute kinetic head of the fluid into a rise in
4025:
A map shows the performance of a compressor and allows determination of optimal operating conditions. It shows the mass flow along the horizontal axis, typically as a percentage of the design mass flow rate, or in actual units. The pressure rise is indicated on the vertical axis as a ratio between
3930:
All compressors have an optimum point relating rotational speed and pressure, with higher compressions requiring higher speeds. Early engines were designed for simplicity, and used a single large compressor spinning at a single speed. Later designs added a second turbine and divided the compressor
2707:
Axial compressors, particularly near their design point are usually amenable to analytical treatment, and a good estimate of their performance can be made before they are first run on a rig. The compressor map shows the complete running range, i.e. off-design, of the compressor from ground idle to
4029:
A surge or stall line identifies the boundary to the left of which the compressor performance rapidly degrades and identifies the maximum pressure ratio that can be achieved for a given mass flow. Contours of efficiency are drawn as well as performance lines for operation at particular rotational
3957:
As an aircraft changes speed or altitude, the pressure of the air at the inlet to the compressor will vary. In order to "tune" the compressor for these changing conditions, designs starting in the 1950s would "bleed" air out of the middle of the compressor in order to avoid trying to compress too
244:
efficiency in the region of 90–95%. To achieve different pressure ratios, axial compressors are designed with different numbers of stages and rotational speeds. As a rule of thumb we can assume that each stage in a given compressor has the same temperature rise (Delta T). Therefore, at the entry,
208:
Axial compressors consist of rotating and stationary components. A shaft drives a central drum which is retained by bearings inside of a stationary tubular casing. Between the drum and the casing are rows of airfoils, each row connected to either the drum or the casing in an alternating manner. A
1940:
3878:
In the jet engine application, the compressor faces a wide variety of operating conditions. On the ground at takeoff the inlet pressure is high, inlet speed zero, and the compressor spun at a variety of speeds as the power is applied. Once in flight the inlet pressure drops, but the inlet speed
3998:
The relative motion of the blades to the fluid adds velocity or pressure or both to the fluid as it passes through the rotor. The fluid velocity is increased through the rotor, and the stator converts kinetic energy to pressure energy. Some diffusion also occurs in the rotor in most practical
3902:
if the inlet conditions change abruptly, a common problem on early engines. In some cases, if the stall occurs near the front of the engine, all of the stages from that point on will stop compressing the air. In this situation the energy required to run the compressor drops suddenly, and the
3848:
simply by adding additional stages and making the engine slightly longer. In the centrifugal-flow design the compressor itself had to be larger in diameter, which was much more difficult to fit properly into a thin and aerodynamic aircraft fuselage (although not dissimilar to the profile of
3620:
This phenomenon will cause vibrations in the whole machine and may lead to mechanical failure. That is why left portion of the curve from the surge point is called unstable region and may cause damage to the machine. So the recommended operation range is on the right side of the surge line.
71:
The energy level of the fluid increases as it flows through the compressor due to the action of the rotor blades which exert a torque on the fluid. The stationary blades slow the fluid, converting the circumferential component of flow into pressure. Compressors are typically driven by an
3509:
3630:
static pressure are constant. In the compressor, a pressure-rise hysteresis is assumed. It is a situation of separation of air flow at the aero-foil blades of the compressor. This phenomenon depending upon the blade-profile leads to reduced compression and drop in engine power.
1300:
1441:
3980:
Closing the variable stators progressively, as compressor speed falls, reduces the slope of the surge (or stall) line on the operating characteristic (or map), improving the surge margin of the installed unit. By incorporating variable stators in the first five stages,
3374:
2708:
its highest corrected rotor speed, which for a civil engine may occur at top-of-climb, or, for a military combat engine, at take-off on a cold day. Not shown is the sub-idle performance region needed for analyzing normal ground and in-flight windmill start behaviour.
876:
3973:, used blades that can be individually rotated around their axis, as opposed to the power axis of the engine. For startup they are rotated to "closed", reducing compression, and then are rotated back into the airflow as the external conditions require. The
3669:
Non-uniformity of air flow in the rotor blades may disturb local air flow in the compressor without upsetting it. The compressor continues to work normally but with reduced compression. Thus, rotating stall decreases the effectiveness of the compressor.
37:
3903:
remaining hot air in the rear of the engine allows the turbine to speed up the whole engine dramatically. This condition, known as surging, was a major problem on early engines and often led to the turbine or compressor breaking and shedding blades.
3534:. This line is formed by joining surge points at different rpms. Unstable flow in axial compressors due to complete breakdown of the steady through flow is termed as surging. This phenomenon affects the performance of compressor and is undesirable.
3710:
produced "reversed turbine" compressors, driven by gas turbines, with blading derived from aerodynamic research which were more efficient than centrifugal types when pumping large flow rates of 40,000 cu.ft. per minute at pressures up to 45 p.s.i.
1583:
3958:
much air in the final stages. This was also used to help start the engine, allowing it to be spun up without compressing much air by bleeding off as much as possible. Bleed systems were already commonly used anyway, to provide airflow into the
1126:
2668:
91:, particularly in relation to their size and cross-section. They do, however, require several rows of airfoils to achieve a large pressure rise, making them complex and expensive relative to other designs (e.g. centrifugal compressors).
993:
1572:
1737:
3882:
There is simply no "perfect" compressor for this wide range of operating conditions. Fixed geometry compressors, like those used on early jet engines, are limited to a design pressure ratio of about 4 or 5:1. As with any
3843:
As
Griffith had originally noted in 1929, the large frontal size of the centrifugal compressor caused it to have higher drag than the narrower axial-flow type. Additionally the axial-flow design could improve its
2974:
3853:
already in widespread use). On the other hand, centrifugal-flow designs remained much less complex (the major reason they "won" in the race to flying examples) and therefore have a role in places where size and
213:
and redirect the flow direction of the fluid to prepare it for the rotor blades of the next stage. The cross-sectional area between rotor drum and casing is reduced in the flow direction to maintain an optimum
3063:
2894:
4405:
2822:
The performance of a compressor is defined according to its design. But in actual practice, the operating point of the compressor deviates from the design- point which is known as off-design operation.
1137:
3400:
1311:
3772:
Real work on axial-flow engines started in the late 1930s, in several efforts that all started at about the same time. In
England, Hayne Constant reached an agreement with the steam turbine company
3769:. Griffith had seen Whittle's work in 1929 and dismissed it, noting a mathematical error, and going on to claim that the frontal size of the engine would make it useless on a high-speed aircraft.
3259:
3125:
720:
3405:
3278:
1967:
3730:
instead of the flat blades would increase efficiency to the point where a practical jet engine was a real possibility. He concluded the paper with a basic diagram of such an engine, which
3166:
3587:
1721:{\displaystyle {\frac {(p_{02})_{\text{actual}}}{p_{01}}}=\left(1+{\frac {\eta _{\text{stage}}\delta (T_{0})_{\text{isentropic}}}{T_{01}}}\right)^{\frac {\gamma }{\gamma -1}}\,}
4398:
3273:
4038:
Operating efficiency is highest close to the stall line. If the downstream pressure is increased beyond the maximum possible the compressor will stall and become unstable.
3194:
64:-based compressor in which the gas or working fluid principally flows parallel to the axis of rotation, or axially. This differs from other rotating compressors such as
1004:
643:
612:
579:
548:
515:
484:
392:
333:
3615:
2816:
2795:
2755:
2734:
688:
451:
423:
361:
302:
3780:
effort based on the
Griffith design in 1938. In 1940, after the successful run of Whittle's centrifugal-flow design, their effort was re-designed as a pure jet, the
708:
4391:
3879:
increases (due to the forward motion of the aircraft) to recover some of this pressure, and the compressor tends to run at a single speed for long periods of time.
2527:
3655:
the entire blade height. Delivery pressure significantly drops with large stalling which can lead to flow reversal. The stage efficiency drops with higher losses.
666:
4017:
engines have fans that operate at Mach 1.7 or more, and require significant containment and noise suppression structures to reduce blade loss damage and noise.
3722:
published a seminal paper in 1926, noting that the reason for the poor performance was that existing compressors used flat blades and were essentially "flying
888:
3617:). This increase and decrease of pressure in pipe will occur repeatedly in pipe and compressor following the cycle E-F-P-G-H-E also known as the surge cycle.
2704:, also known as a characteristic, by plotting pressure ratio and efficiency against corrected mass flow at different values of corrected compressor speed.
1935:{\displaystyle {\frac {(p_{02})_{\text{actual}}}{p_{01}}}=\left(1+{\frac {\eta _{\text{stage}}U}{T_{01}c_{p}}}\left\right)^{\frac {\gamma }{\gamma -1}}\,}
1455:
4784:
3926:
represent the rotational speed of the low- and high-pressure compressors respectively. Both are presented on the indicator as a percentage of design rpm.
102:, high speed ship engines, and small scale power stations. They are also used in industrial applications such as large volume air separation plants,
4774:
3651:
Negative stall is negligible compared to the positive stall because flow separation is least likely to occur on the pressure side of the blade.
4747:
4372:
Wilson, David Gordon and
Theodosios Korakianitis. 'The Design of High-Efficiency Turbomachinery and Turbines,' 2nd edn, Prentice Hall, 1998.
4111:
3745:
measurement, little work appears to have started as a direct result of his paper. The only obvious effort was a test-bed compressor built by
3784:. In Germany, von Ohain had produced several working centrifugal engines, some of which had flown including the world's first jet aircraft (
4334:
2913:
4779:
68:, axi-centrifugal compressors and mixed-flow compressors where the fluid flow will include a "radial component" through the compressor.
2994:
2831:
4002:
The increase in velocity of the fluid is primarily in the tangential direction (swirl) and the stator removes this angular momentum.
4377:
4366:
4355:
4344:
4149:
3982:
3833:
3714:
Because early axial compressors were not efficient enough a number of papers in the early 1920s claimed that a practical axial-flow
2772:
4162:
Greitzer, E. M. (1 April 1976). "Surge and
Rotating Stall in Axial Flow Compressors—Part I: Theoretical Compression System Model".
1295:{\displaystyle P={\dot {m}}U\left(V_{f2}\tan \alpha _{2}-V_{f1}\tan \alpha _{1}\right)={\dot {m}}c_{p}\left(T_{02}-T_{01}\right)\,}
3504:{\displaystyle {\begin{aligned}\psi &=1-J(\phi )\,\\\psi &=1-\phi \left({\frac {1-\psi '}{\phi '}}\right)\,\end{aligned}}}
4647:
1436:{\displaystyle \delta (T_{0})_{\text{isentropic}}={\frac {U}{c_{p}}}\left(V_{f2}\tan \alpha _{2}-V_{f1}\tan \alpha _{1}\right)\,}
2678:
4298:
3906:
For all of these reasons, axial compressors on modern jet engines are considerably more complex than those on earlier designs.
4696:
871:{\displaystyle F={\dot {m}}\left(V_{w2}-V_{w1}\right)={\dot {m}}\left(V_{f2}\tan \alpha _{2}-V_{f1}\tan \alpha _{1}\right)\,}
4258:
3693:
These forced vibrations may match with the natural frequency of the blades causing resonance and hence failure of the blade.
3202:
3071:
3836:
also entered the race in 1942, their project proving to be the only successful one of the US efforts, later becoming the
3750:
4732:
3530:
In the plot of pressure-flow rate the line separating graph between two regions- unstable and stable is known as the
2760:
Stage pressure ratio against flow rate is lower than for a no-loss stage as shown. Losses are due to blade friction,
114:. Due to high performance, high reliability and flexible operation during the flight envelope, they are also used in
3977:
was the first major example of a variable stator design, and today it is a common feature of most military engines.
4727:
4503:
4237:
4312:
4526:
4350:
Kerrebrock, Jack L. 'Aircraft
Engines and Gas Turbines,' 2nd edn, Cambridge, Massachusetts: The MIT Press, 1992.
4060:
4910:
4804:
4722:
4582:
3703:
3130:
231:. If 50% of the pressure rise in a stage is obtained at the rotor section, it is said to have a 50% reaction.
4676:
4463:
4339:
Hill, Philip and Carl
Peterson. 'Mechanics and Thermodynamics of Propulsion,' 2nd edn, Prentice Hall, 1991.
4189:
198:
4313:"The Nuclear-Powered Jet Engine, Ceramic Turbines and Other Gems from the History of Flight | GE News"
269:
states that the sum of the moments of external forces acting on a fluid which is temporarily occupying the
4652:
4622:
4617:
4541:
4458:
4054:
4006:
3762:
3369:{\displaystyle {\begin{aligned}\psi '&=1-J(\phi ')\,\\J&={\frac {1-\psi '}{\phi '}}\end{aligned}}}
65:
4889:
4657:
4627:
4607:
3895:, so there is very strong financial need to improve the compressor stages beyond these sorts of ratios.
3549:
4144:
Perry, R.H. and Green, D.W. (Eds.) (2007). Perry's
Chemical Engineers' Handbook (8th ed.). McGraw Hill.
3707:
4361:
Rangwalla, Abdulla. S. 'Turbo-Machinery
Dynamics: Design and Operation,' New York: McGraw-Hill: 2005.
3702:
From an energy exchange point of view axial compressors are reversed turbines. Steam-turbine designer
4874:
4837:
4789:
4551:
3974:
3825:
3813:
3805:
3773:
3719:
4329:
Treager, Irwin E. 'Aircraft Gas Turbine Engine Technology' 3rd edn, McGraw-Hill Book Company, 1995,
3914:
4042:
3936:
3871:
3171:
1121:{\displaystyle P={\dot {m}}\left(h_{02}-h_{01}\right)={\dot {m}}c_{p}\left(T_{02}-T_{01}\right)\,}
83:
Axial flow compressors produce a continuous flow of compressed gas, and have the benefits of high
4742:
4691:
4284:
The Engineer magazine May 27, 1938 Supplement The Development Of Blowers And Compressors p.xxxiii
3985:
has developed a ten-stage axial compressor capable of operating at a 23:1 design pressure ratio.
3789:
3962:
stage where it was used to cool the turbine blades, as well as provide pressurized air for the
193:
4769:
4561:
4373:
4362:
4351:
4340:
4330:
4145:
4107:
3940:
3892:
3845:
3723:
2663:{\displaystyle R={\frac {V_{r1}^{2}-V_{r2}^{2}}{V_{r1}^{2}-V_{r2}^{2}+V_{1}^{2}-V_{2}^{2}}}\,}
617:
586:
553:
522:
489:
458:
366:
307:
3592:
3526:
Various points on the performance curve depending upon the flow rates and pressure difference
2800:
2779:
2739:
2718:
673:
428:
400:
338:
279:
4869:
4662:
4632:
4602:
4219:
4171:
4066:
3963:
3899:
3837:
3817:
3742:
3664:
693:
266:
31:
1948:, The pressure difference between the entry and exit of the rotor blade is called reaction
4884:
4827:
4521:
4449:
4418:
4072:
3888:
3715:
2761:
201:
111:
988:{\displaystyle P={\dot {m}}U\left(V_{f2}\tan \alpha _{2}-V_{f1}\tan \alpha _{1}\right)\,}
650:
4383:
4009:
rise. For a given geometry the temperature rise depends on the square of the tangential
257:
4434:
3850:
3785:
3758:
3746:
2701:
2682:
Reasons stating difference in ideal and actual performance curve in an axial compressor
270:
88:
73:
57:
53:
4210:
McDougall, NM; Cumpsty, NA; Hynes, TP (2012). "Stall inception in axial compressors".
3522:
4904:
4794:
4592:
4566:
4498:
3781:
3754:
3738:
2776:
Off design characteristics curve of an axial compressor. Stage loading coefficient (
2712:
228:
118:
103:
1567:{\displaystyle p_{2}-p_{1}=p_{1}\left(\left^{\frac {\gamma }{\gamma -1}}-1\right)\,}
4848:
4822:
4812:
4642:
4597:
3821:
3809:
3766:
95:
4717:
4712:
4531:
4429:
4421:
4010:
3884:
3855:
273:
is equal to the net change of angular momentum flux through the control volume.
215:
99:
3931:
into low-pressure and high-pressure sections, the latter spinning faster. This
36:
4488:
4414:
3687:
241:
174:
84:
4879:
4737:
4587:
4546:
4483:
4078:
3952:
3777:
3731:
261:
Velocity triangle of the swirling fluid entering and exiting the rotor blade
210:
158:
115:
107:
3866:
17:
4853:
4612:
4556:
4478:
4473:
4454:
4014:
3820:
were awarded contracts in 1941 to develop axial-flow engines, the former
3793:
3514:
for positive values of J, slope of the curve is negative and vice versa.
3127:
doesn't change for a wide range of operating points till stalling. Also
1949:
40:
An animated simulation of an axial compressor. The static blades are the
4468:
4057: – Sub-class of dynamic axisymmetric work-absorbing turbomachinery
3959:
3829:
3801:
3727:
3638:
645:
are the blade-relative velocities at the inlet and outlet respectively.
61:
4281:
4223:
4175:
2711:
The performance of a single compressor stage may be shown by plotting
4637:
4493:
2969:{\displaystyle \tan \alpha _{2}={\frac {1}{\phi }}-\tan \beta _{2}\,}
882:
Power consumed by an ideal moving blade, P is given by the equation:
41:
3804:), which used axial-flow designs in the world's first jet fighter (
517:
are the axial flow velocities at the inlet and outlet respectively.
4817:
3913:
3865:
3521:
2677:
256:
192:
77:
35:
3828:
also started their own project to develop a turboprop, which the
3058:{\displaystyle \psi =1-\phi (\tan \beta _{2}+\tan \alpha _{1})\,}
453:
are the absolute velocities at the inlet and outlet respectively.
121:, as fuel pumps and in other critical high volume applications.
4131:
3168:
because of minor change in air angle at rotor and stator, where
2889:{\displaystyle \psi =\phi (\tan \alpha _{2}-\tan \alpha _{1})\,}
4387:
4069: – Fan that induces gas flow mostly parallel to the shaft
4063: – Brief description of components needed for jet engines
3797:
581:
are the swirl velocities at the inlet and outlet respectively.
3737:
Although Griffith was well known due to his earlier work on
3732:
included a second turbine that was used to power a propeller
4190:"Practical considerations when designing the engine cycle"
4045:
of the system, taking the downstream plenum into account.
4075: – Type of pump consisting of a propeller in a pipe
3647:
Flow separation occur on the pressure side of the blade.
714:
Rate of change of momentum, F is given by the equation:
276:
The swirling fluid enters the control volume at radius,
3718:
would be impossible to construct. Things changed after
3690:
in the blades due to passage through stall compartment.
3761:, were based on the more robust and better understood
1952:. The change in pressure energy is calculated through
94:
Axial compressors are integral to the design of large
3595:
3552:
3403:
3276:
3254:{\displaystyle J=\tan \beta _{2}+\tan \alpha _{3})\,}
3205:
3174:
3133:
3074:
2997:
2916:
2834:
2803:
2782:
2742:
2721:
2530:
1965:
1740:
1586:
1458:
1314:
1140:
1007:
891:
723:
696:
676:
653:
620:
589:
556:
525:
492:
461:
431:
403:
369:
341:
310:
282:
4125:
4123:
3120:{\displaystyle (\tan \beta _{2}+\tan \alpha _{1})\,}
4862:
4836:
4803:
4760:
4705:
4684:
4675:
4575:
4512:
4442:
4428:
4785:Engine-indicating and crew-alerting system (EICAS)
3609:
3581:
3503:
3368:
3253:
3188:
3160:
3119:
3057:
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2810:
2789:
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2728:
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1934:
1720:
1566:
1435:
1294:
1120:
987:
870:
702:
682:
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637:
606:
573:
542:
509:
478:
445:
417:
386:
355:
327:
296:
4818:Full Authority Digital Engine/Electronics (FADEC)
4164:Journal of Engineering for Gas Turbines and Power
3943:, used on a wide variety of commercial aircraft.
4775:Electronic centralised aircraft monitor (ECAM)
4106:. Tata McGraw Hill Education Private Limited.
998:Change in enthalpy of fluid in moving blades:
4399:
8:
3870:Low-pressure axial compressor scheme of the
3753:. Other early jet efforts, notably those of
3788:), but development efforts had moved on to
2700:Axial compressor performance is shown on a
218:axial velocity as the fluid is compressed.
27:Machine for continuous flow gas compression
4780:Electronic flight instrument system (EFIS)
4681:
4439:
4406:
4392:
4384:
4295:Pilot's Handbook of Aeronautical Knowledge
4041:Typically the instability will be at the
3683:This reduces efficiency of the compressor
3606:
3600:
3594:
3578:
3572:
3554:
3553:
3551:
3496:
3464:
3436:
3404:
3402:
3334:
3319:
3277:
3275:
3250:
3241:
3222:
3204:
3185:
3179:
3173:
3161:{\displaystyle \alpha _{1}=\alpha _{3}\,}
3157:
3151:
3138:
3132:
3116:
3107:
3088:
3073:
3054:
3045:
3026:
2996:
2965:
2959:
2936:
2927:
2915:
2885:
2876:
2857:
2833:
2807:
2802:
2786:
2781:
2746:
2741:
2725:
2720:
2659:
2650:
2645:
2632:
2627:
2614:
2606:
2593:
2585:
2573:
2565:
2552:
2544:
2537:
2529:
2495:
2481:
2473:
2467:
2455:
2441:
2433:
2427:
2414:
2401:
2382:
2374:
2368:
2354:
2346:
2340:
2327:
2314:
2285:
2280:
2274:
2260:
2255:
2249:
2235:
2222:
2202:
2201:
2168:
2154:
2149:
2143:
2134:
2113:
2099:
2094:
2088:
2079:
2064:
2049:
2048:
2025:
2012:
2000:
1987:
1980:
1966:
1964:
1931:
1912:
1896:
1877:
1864:
1845:
1827:
1817:
1802:
1795:
1772:
1761:
1751:
1741:
1739:
1717:
1698:
1685:
1674:
1664:
1648:
1641:
1618:
1607:
1597:
1587:
1585:
1563:
1533:
1521:
1511:
1505:
1489:
1476:
1463:
1457:
1432:
1421:
1402:
1389:
1370:
1353:
1344:
1335:
1325:
1313:
1291:
1280:
1267:
1252:
1237:
1236:
1222:
1203:
1190:
1171:
1148:
1147:
1139:
1117:
1106:
1093:
1078:
1063:
1062:
1048:
1035:
1015:
1014:
1006:
984:
973:
954:
941:
922:
899:
898:
890:
867:
856:
837:
824:
805:
785:
784:
767:
751:
731:
730:
722:
695:
675:
657:
652:
634:
625:
619:
603:
594:
588:
570:
561:
555:
539:
530:
524:
506:
497:
491:
475:
466:
460:
442:
436:
430:
414:
408:
402:
383:
374:
368:
352:
346:
340:
324:
315:
309:
293:
287:
281:
4277:
4275:
2771:
2764:, unsteady flow and vane-blade spacing.
123:
4097:
4095:
4091:
3994:Energy exchange between rotor and fluid
3546:Suppose the initial operating point D (
240:1.15–1.6) at design conditions with a
4026:inlet and exit stagnation pressures.
3918:A dual-spool axial-flow compressor. N
2736:) as a function of flow coefficient (
1447:Isentropic compression in rotor blade
7:
4081: – Pump driven by a gas turbine
3776:(Metrovick) in 1937, starting their
3267:
3265:Representing design values with (')
2907:
2825:
668:is the linear velocity of the blade.
4282:https://gracesguide.co.uk/Main_Page
2797:) as function of flow coefficient (
4238:"Turbo Compresser and Pump Patent"
3582:{\displaystyle {\dot {m}},P_{D}\,}
25:
3983:General Electric Aircraft Engines
4648:Thrust specific fuel consumption
3898:Additionally the compressor may
3388:for off-design operations (from
4299:Federal Aviation Administration
4245:patentimages.storage.googleapis
4005:The pressure rise results in a
3832:eventually contracted in 1943.
4697:Propeller speed reduction unit
4104:Turbines, Compressors and Fans
3812:). In the United States, both
3749:, Griffith's colleague at the
3433:
3427:
3316:
3305:
3247:
3113:
3075:
3051:
3013:
2882:
2844:
1758:
1744:
1671:
1657:
1604:
1590:
1332:
1318:
1:
3966:systems inside the aircraft.
3726:". He showed that the use of
3637:Flow separation occur on the
3189:{\displaystyle \alpha _{3}\,}
253:Kinetics and energy equations
4301:. 2016-08-24. pp. 7–23.
4132:"2.0 Axial Flow Compressors"
3969:A more advanced design, the
3751:Royal Aircraft Establishment
690:is the guide vane angle and
363:, with tangential velocity,
304:, with tangential velocity,
4608:Engine pressure ratio (EPR)
3947:Bleed air, variable stators
3891:is strongly related to the
3390:
2674:Performance characteristics
4927:
4875:Auxiliary power unit (APU)
4504:Rotating detonation engine
4013:of the rotor row. Current
3950:
3824:, the latter a turboprop.
3662:
2988:from equation (1) and (2)
110:cracking air, and propane
29:
4212:Journal of Turbomachinery
4061:Components of jet engines
3935:design, pioneered on the
3765:which was widely used in
3196:is diffuser blade angle.
4583:Aircraft engine starting
3704:Charles Algernon Parsons
2696:Steady-state performance
878:(from velocity triangle)
638:{\displaystyle V_{r2}\,}
607:{\displaystyle V_{r1}\,}
574:{\displaystyle V_{w2}\,}
543:{\displaystyle V_{w1}\,}
510:{\displaystyle V_{f2}\,}
479:{\displaystyle V_{f1}\,}
387:{\displaystyle V_{w2}\,}
335:, and leaves at radius,
328:{\displaystyle V_{w1}\,}
199:Pratt & Whitney TF30
133:Pressure ratio per stage
4464:Pulse detonation engine
3610:{\displaystyle P_{H}\,}
2811:{\displaystyle \phi \,}
2790:{\displaystyle \psi \,}
2750:{\displaystyle \phi \,}
2729:{\displaystyle \psi \,}
683:{\displaystyle \alpha }
446:{\displaystyle V_{2}\,}
418:{\displaystyle V_{1}\,}
356:{\displaystyle r_{2}\,}
297:{\displaystyle r_{1}\,}
4653:Thrust to weight ratio
4623:Overall pressure ratio
4618:Jet engine performance
4542:Centrifugal compressor
4459:Gluhareff Pressure Jet
4055:Centrifugal compressor
4007:stagnation temperature
3927:
3875:
3862:Axial-flow jet engines
3858:are not so important.
3763:centrifugal compressor
3708:Brown Boveri & Cie
3611:
3583:
3527:
3505:
3370:
3255:
3190:
3162:
3121:
3059:
2970:
2890:
2819:
2812:
2791:
2751:
2730:
2683:
2664:
2512:
1936:
1722:
1568:
1437:
1296:
1122:
989:
872:
704:
703:{\displaystyle \beta }
684:
662:
639:
608:
575:
544:
511:
480:
447:
419:
388:
357:
329:
298:
262:
205:
66:centrifugal compressor
56:that can continuously
45:
4890:Ice protection system
4658:Variable cycle engine
4628:Propulsive efficiency
4034:Compression stability
3917:
3869:
3612:
3584:
3525:
3506:
3371:
3256:
3191:
3163:
3122:
3060:
2971:
2891:
2813:
2792:
2775:
2752:
2731:
2681:
2665:
2513:
1937:
1723:
1569:
1438:
1297:
1123:
990:
873:
705:
685:
663:
640:
609:
576:
545:
512:
481:
448:
420:
389:
358:
330:
299:
260:
196:
136:Efficiency per stage
39:
30:Further information:
4790:Flight data recorder
4552:Constant speed drive
4532:Afterburner (reheat)
4266:webserver.dmt.upm.es
4259:"NASA-SP36_extracto"
4102:Yahya, S.M. (2011).
3975:General Electric J79
3806:Messerschmitt Me 262
3774:Metropolitan-Vickers
3593:
3550:
3401:
3274:
3203:
3172:
3131:
3072:
2995:
2914:
2832:
2801:
2780:
2768:Off-design operation
2740:
2719:
2528:
1963:
1738:
1584:
1456:
1312:
1138:
1005:
889:
721:
694:
674:
651:
618:
587:
554:
523:
490:
459:
429:
401:
367:
339:
308:
280:
197:The compressor in a
60:. It is a rotating,
4130:Meherwan, P.Boyce.
4043:Helmholtz frequency
2655:
2637:
2619:
2598:
2578:
2557:
2486:
2446:
2387:
2359:
2290:
2265:
2159:
2104:
710:is the blade angle.
661:{\displaystyle U\,}
127:Typical application
4692:Propeller governor
3928:
3876:
3808:) and jet bomber (
3641:side of the blade.
3607:
3579:
3528:
3501:
3499:
3366:
3364:
3251:
3186:
3158:
3117:
3055:
2966:
2886:
2820:
2808:
2787:
2747:
2726:
2684:
2660:
2641:
2623:
2602:
2581:
2561:
2540:
2508:
2506:
2469:
2429:
2370:
2342:
2276:
2251:
2145:
2090:
1954:degree of reaction
1946:Degree of Reaction
1932:
1718:
1564:
1433:
1292:
1118:
985:
868:
700:
680:
658:
635:
604:
571:
540:
507:
476:
443:
415:
384:
353:
325:
294:
267:moment of momentum
263:
206:
80:or a gas turbine.
46:
4898:
4897:
4770:Annunciator panel
4756:
4755:
4671:
4670:
4562:Propelling nozzle
4224:10.1115/1.2927406
4176:10.1115/1.3446138
4113:978-0-07-070702-3
3941:Rolls-Royce RB211
3893:compression ratio
3846:compression ratio
3659:Rotating stalling
3644:Negative stalling
3634:Positive stalling
3562:
3490:
3386:
3385:
3360:
2986:
2985:
2944:
2906:
2905:
2657:
2502:
2462:
2391:
2363:
2294:
2269:
2210:
2175:
2120:
2057:
2032:
1928:
1834:
1805:
1778:
1764:
1714:
1691:
1677:
1651:
1624:
1610:
1549:
1527:
1359:
1338:
1245:
1156:
1071:
1023:
907:
793:
739:
186:
185:
16:(Redirected from
4918:
4885:Hydraulic system
4880:Bleed air system
4870:Air-start system
4733:Counter-rotating
4682:
4663:Windmill restart
4633:Specific impulse
4603:Compressor stall
4537:Axial compressor
4440:
4408:
4401:
4394:
4385:
4335:978-0-02-8018287
4317:
4316:
4309:
4303:
4302:
4291:
4285:
4279:
4270:
4269:
4263:
4255:
4249:
4248:
4242:
4234:
4228:
4227:
4207:
4201:
4200:
4197:www.sto.nato.int
4194:
4186:
4180:
4179:
4159:
4153:
4142:
4136:
4135:
4127:
4118:
4117:
4099:
4067:Axial fan design
3964:air conditioning
3818:General Electric
3665:Compressor stall
3616:
3614:
3613:
3608:
3605:
3604:
3588:
3586:
3585:
3580:
3577:
3576:
3564:
3563:
3555:
3510:
3508:
3507:
3502:
3500:
3495:
3491:
3489:
3481:
3480:
3465:
3375:
3373:
3372:
3367:
3365:
3361:
3359:
3351:
3350:
3335:
3315:
3288:
3268:
3260:
3258:
3257:
3252:
3246:
3245:
3227:
3226:
3195:
3193:
3192:
3187:
3184:
3183:
3167:
3165:
3164:
3159:
3156:
3155:
3143:
3142:
3126:
3124:
3123:
3118:
3112:
3111:
3093:
3092:
3064:
3062:
3061:
3056:
3050:
3049:
3031:
3030:
2975:
2973:
2972:
2967:
2964:
2963:
2945:
2937:
2932:
2931:
2908:
2895:
2893:
2892:
2887:
2881:
2880:
2862:
2861:
2826:
2817:
2815:
2814:
2809:
2796:
2794:
2793:
2788:
2756:
2754:
2753:
2748:
2735:
2733:
2732:
2727:
2669:
2667:
2666:
2661:
2658:
2656:
2654:
2649:
2636:
2631:
2618:
2613:
2597:
2592:
2579:
2577:
2572:
2556:
2551:
2538:
2517:
2515:
2514:
2509:
2507:
2503:
2501:
2500:
2499:
2485:
2480:
2468:
2463:
2461:
2460:
2459:
2445:
2440:
2428:
2419:
2418:
2406:
2405:
2392:
2386:
2381:
2369:
2364:
2358:
2353:
2341:
2332:
2331:
2319:
2318:
2305:
2301:
2300:
2296:
2295:
2289:
2284:
2275:
2270:
2264:
2259:
2250:
2240:
2239:
2227:
2226:
2212:
2211:
2203:
2186:
2182:
2181:
2177:
2176:
2174:
2173:
2172:
2158:
2153:
2144:
2139:
2138:
2121:
2119:
2118:
2117:
2103:
2098:
2089:
2084:
2083:
2069:
2068:
2059:
2058:
2050:
2033:
2031:
2030:
2029:
2017:
2016:
2006:
2005:
2004:
1992:
1991:
1981:
1941:
1939:
1938:
1933:
1930:
1929:
1927:
1913:
1911:
1907:
1906:
1902:
1901:
1900:
1885:
1884:
1869:
1868:
1853:
1852:
1835:
1833:
1832:
1831:
1822:
1821:
1811:
1807:
1806:
1803:
1796:
1779:
1777:
1776:
1767:
1766:
1765:
1762:
1756:
1755:
1742:
1727:
1725:
1724:
1719:
1716:
1715:
1713:
1699:
1697:
1693:
1692:
1690:
1689:
1680:
1679:
1678:
1675:
1669:
1668:
1653:
1652:
1649:
1642:
1625:
1623:
1622:
1613:
1612:
1611:
1608:
1602:
1601:
1588:
1573:
1571:
1570:
1565:
1562:
1558:
1551:
1550:
1548:
1534:
1532:
1528:
1526:
1525:
1516:
1515:
1506:
1494:
1493:
1481:
1480:
1468:
1467:
1442:
1440:
1439:
1434:
1431:
1427:
1426:
1425:
1410:
1409:
1394:
1393:
1378:
1377:
1360:
1358:
1357:
1345:
1340:
1339:
1336:
1330:
1329:
1301:
1299:
1298:
1293:
1290:
1286:
1285:
1284:
1272:
1271:
1257:
1256:
1247:
1246:
1238:
1232:
1228:
1227:
1226:
1211:
1210:
1195:
1194:
1179:
1178:
1158:
1157:
1149:
1127:
1125:
1124:
1119:
1116:
1112:
1111:
1110:
1098:
1097:
1083:
1082:
1073:
1072:
1064:
1058:
1054:
1053:
1052:
1040:
1039:
1025:
1024:
1016:
994:
992:
991:
986:
983:
979:
978:
977:
962:
961:
946:
945:
930:
929:
909:
908:
900:
877:
875:
874:
869:
866:
862:
861:
860:
845:
844:
829:
828:
813:
812:
795:
794:
786:
780:
776:
775:
774:
759:
758:
741:
740:
732:
709:
707:
706:
701:
689:
687:
686:
681:
667:
665:
664:
659:
644:
642:
641:
636:
633:
632:
613:
611:
610:
605:
602:
601:
580:
578:
577:
572:
569:
568:
549:
547:
546:
541:
538:
537:
516:
514:
513:
508:
505:
504:
485:
483:
482:
477:
474:
473:
452:
450:
449:
444:
441:
440:
424:
422:
421:
416:
413:
412:
393:
391:
390:
385:
382:
381:
362:
360:
359:
354:
351:
350:
334:
332:
331:
326:
323:
322:
303:
301:
300:
295:
292:
291:
124:
58:pressurize gases
50:axial compressor
32:Axial fan design
21:
4926:
4925:
4921:
4920:
4919:
4917:
4916:
4915:
4911:Gas compressors
4901:
4900:
4899:
4894:
4858:
4841:
4832:
4828:Thrust reversal
4805:Engine controls
4799:
4762:
4752:
4728:Contra-rotating
4701:
4667:
4571:
4522:Accessory drive
4514:
4508:
4450:Air turborocket
4432:
4424:
4412:
4326:
4321:
4320:
4311:
4310:
4306:
4293:
4292:
4288:
4280:
4273:
4261:
4257:
4256:
4252:
4240:
4236:
4235:
4231:
4209:
4208:
4204:
4192:
4188:
4187:
4183:
4161:
4160:
4156:
4143:
4139:
4129:
4128:
4121:
4114:
4101:
4100:
4093:
4088:
4073:Axial-flow pump
4051:
4036:
4023:
4021:Compressor maps
3996:
3991:
3971:variable stator
3955:
3949:
3937:Bristol Olympus
3925:
3921:
3912:
3889:fuel efficiency
3864:
3716:turbojet engine
3700:
3680:
3667:
3661:
3627:
3596:
3591:
3590:
3568:
3548:
3547:
3540:
3520:
3498:
3497:
3482:
3473:
3466:
3460:
3444:
3438:
3437:
3411:
3399:
3398:
3363:
3362:
3352:
3343:
3336:
3327:
3321:
3320:
3308:
3289:
3281:
3272:
3271:
3237:
3218:
3201:
3200:
3175:
3170:
3169:
3147:
3134:
3129:
3128:
3103:
3084:
3070:
3069:
3041:
3022:
2993:
2992:
2955:
2923:
2912:
2911:
2872:
2853:
2830:
2829:
2799:
2798:
2778:
2777:
2770:
2762:flow separation
2738:
2737:
2717:
2716:
2698:
2689:
2676:
2580:
2539:
2526:
2525:
2505:
2504:
2491:
2487:
2451:
2447:
2420:
2410:
2397:
2394:
2393:
2333:
2323:
2310:
2307:
2306:
2248:
2244:
2231:
2218:
2217:
2213:
2194:
2188:
2187:
2164:
2160:
2130:
2129:
2125:
2109:
2105:
2075:
2074:
2070:
2060:
2041:
2035:
2034:
2021:
2008:
2007:
1996:
1983:
1982:
1973:
1961:
1960:
1917:
1892:
1873:
1860:
1841:
1840:
1836:
1823:
1813:
1812:
1798:
1797:
1788:
1784:
1783:
1768:
1757:
1747:
1743:
1736:
1735:
1703:
1681:
1670:
1660:
1644:
1643:
1634:
1630:
1629:
1614:
1603:
1593:
1589:
1582:
1581:
1538:
1517:
1507:
1501:
1500:
1499:
1495:
1485:
1472:
1459:
1454:
1453:
1417:
1398:
1385:
1366:
1365:
1361:
1349:
1331:
1321:
1310:
1309:
1305:which implies,
1276:
1263:
1262:
1258:
1248:
1218:
1199:
1186:
1167:
1166:
1162:
1136:
1135:
1102:
1089:
1088:
1084:
1074:
1044:
1031:
1030:
1026:
1003:
1002:
969:
950:
937:
918:
917:
913:
887:
886:
852:
833:
820:
801:
800:
796:
763:
747:
746:
742:
719:
718:
692:
691:
672:
671:
649:
648:
621:
616:
615:
590:
585:
584:
557:
552:
551:
526:
521:
520:
493:
488:
487:
462:
457:
456:
432:
427:
426:
404:
399:
398:
370:
365:
364:
342:
337:
336:
311:
306:
305:
283:
278:
277:
255:
237:
224:
202:turbofan engine
191:
112:dehydrogenation
34:
28:
23:
22:
15:
12:
11:
5:
4924:
4922:
4914:
4913:
4903:
4902:
4896:
4895:
4893:
4892:
4887:
4882:
4877:
4872:
4866:
4864:
4860:
4859:
4857:
4856:
4851:
4845:
4843:
4834:
4833:
4831:
4830:
4825:
4820:
4815:
4809:
4807:
4801:
4800:
4798:
4797:
4792:
4787:
4782:
4777:
4772:
4766:
4764:
4758:
4757:
4754:
4753:
4751:
4750:
4748:Variable-pitch
4745:
4740:
4735:
4730:
4725:
4723:Constant-speed
4720:
4715:
4709:
4707:
4703:
4702:
4700:
4699:
4694:
4688:
4686:
4679:
4673:
4672:
4669:
4668:
4666:
4665:
4660:
4655:
4650:
4645:
4640:
4635:
4630:
4625:
4620:
4615:
4610:
4605:
4600:
4595:
4590:
4585:
4579:
4577:
4573:
4572:
4570:
4569:
4564:
4559:
4554:
4549:
4544:
4539:
4534:
4529:
4524:
4518:
4516:
4510:
4509:
4507:
4506:
4501:
4496:
4491:
4486:
4481:
4476:
4471:
4466:
4461:
4452:
4446:
4444:
4437:
4435:jet propulsion
4426:
4425:
4413:
4411:
4410:
4403:
4396:
4388:
4382:
4381:
4370:
4359:
4348:
4337:
4325:
4322:
4319:
4318:
4304:
4286:
4271:
4250:
4229:
4218:(1): 116–123.
4202:
4181:
4170:(2): 190–198.
4154:
4137:
4119:
4112:
4090:
4089:
4087:
4084:
4083:
4082:
4076:
4070:
4064:
4058:
4050:
4047:
4035:
4032:
4022:
4019:
3995:
3992:
3990:
3987:
3948:
3945:
3923:
3919:
3911:
3908:
3863:
3860:
3851:radial engines
3759:Hans von Ohain
3747:Hayne Constant
3720:A. A. Griffith
3699:
3696:
3695:
3694:
3691:
3684:
3679:
3676:
3660:
3657:
3649:
3648:
3645:
3642:
3635:
3626:
3623:
3603:
3599:
3575:
3571:
3567:
3561:
3558:
3539:
3536:
3519:
3516:
3512:
3511:
3494:
3488:
3485:
3479:
3476:
3472:
3469:
3463:
3459:
3456:
3453:
3450:
3447:
3445:
3443:
3440:
3439:
3435:
3432:
3429:
3426:
3423:
3420:
3417:
3414:
3412:
3410:
3407:
3406:
3384:
3383:
3378:
3376:
3358:
3355:
3349:
3346:
3342:
3339:
3333:
3330:
3328:
3326:
3323:
3322:
3318:
3314:
3311:
3307:
3304:
3301:
3298:
3295:
3292:
3290:
3287:
3284:
3280:
3279:
3263:
3262:
3249:
3244:
3240:
3236:
3233:
3230:
3225:
3221:
3217:
3214:
3211:
3208:
3182:
3178:
3154:
3150:
3146:
3141:
3137:
3115:
3110:
3106:
3102:
3099:
3096:
3091:
3087:
3083:
3080:
3077:
3066:
3065:
3053:
3048:
3044:
3040:
3037:
3034:
3029:
3025:
3021:
3018:
3015:
3012:
3009:
3006:
3003:
3000:
2984:
2983:
2978:
2976:
2962:
2958:
2954:
2951:
2948:
2943:
2940:
2935:
2930:
2926:
2922:
2919:
2904:
2903:
2898:
2896:
2884:
2879:
2875:
2871:
2868:
2865:
2860:
2856:
2852:
2849:
2846:
2843:
2840:
2837:
2806:
2785:
2769:
2766:
2745:
2724:
2702:compressor map
2697:
2694:
2688:
2685:
2675:
2672:
2671:
2670:
2653:
2648:
2644:
2640:
2635:
2630:
2626:
2622:
2617:
2612:
2609:
2605:
2601:
2596:
2591:
2588:
2584:
2576:
2571:
2568:
2564:
2560:
2555:
2550:
2547:
2543:
2536:
2533:
2519:
2518:
2498:
2494:
2490:
2484:
2479:
2476:
2472:
2466:
2458:
2454:
2450:
2444:
2439:
2436:
2432:
2426:
2423:
2421:
2417:
2413:
2409:
2404:
2400:
2396:
2395:
2390:
2385:
2380:
2377:
2373:
2367:
2362:
2357:
2352:
2349:
2345:
2339:
2336:
2334:
2330:
2326:
2322:
2317:
2313:
2309:
2308:
2304:
2299:
2293:
2288:
2283:
2279:
2273:
2268:
2263:
2258:
2254:
2247:
2243:
2238:
2234:
2230:
2225:
2221:
2216:
2209:
2206:
2200:
2197:
2195:
2193:
2190:
2189:
2185:
2180:
2171:
2167:
2163:
2157:
2152:
2148:
2142:
2137:
2133:
2128:
2124:
2116:
2112:
2108:
2102:
2097:
2093:
2087:
2082:
2078:
2073:
2067:
2063:
2056:
2053:
2047:
2044:
2042:
2040:
2037:
2036:
2028:
2024:
2020:
2015:
2011:
2003:
1999:
1995:
1990:
1986:
1979:
1976:
1974:
1972:
1969:
1968:
1943:
1942:
1926:
1923:
1920:
1916:
1910:
1905:
1899:
1895:
1891:
1888:
1883:
1880:
1876:
1872:
1867:
1863:
1859:
1856:
1851:
1848:
1844:
1839:
1830:
1826:
1820:
1816:
1810:
1801:
1794:
1791:
1787:
1782:
1775:
1771:
1760:
1754:
1750:
1746:
1731:which implies
1729:
1728:
1712:
1709:
1706:
1702:
1696:
1688:
1684:
1673:
1667:
1663:
1659:
1656:
1647:
1640:
1637:
1633:
1628:
1621:
1617:
1606:
1600:
1596:
1592:
1575:
1574:
1561:
1557:
1554:
1547:
1544:
1541:
1537:
1531:
1524:
1520:
1514:
1510:
1504:
1498:
1492:
1488:
1484:
1479:
1475:
1471:
1466:
1462:
1444:
1443:
1430:
1424:
1420:
1416:
1413:
1408:
1405:
1401:
1397:
1392:
1388:
1384:
1381:
1376:
1373:
1369:
1364:
1356:
1352:
1348:
1343:
1334:
1328:
1324:
1320:
1317:
1303:
1302:
1289:
1283:
1279:
1275:
1270:
1266:
1261:
1255:
1251:
1244:
1241:
1235:
1231:
1225:
1221:
1217:
1214:
1209:
1206:
1202:
1198:
1193:
1189:
1185:
1182:
1177:
1174:
1170:
1165:
1161:
1155:
1152:
1146:
1143:
1129:
1128:
1115:
1109:
1105:
1101:
1096:
1092:
1087:
1081:
1077:
1070:
1067:
1061:
1057:
1051:
1047:
1043:
1038:
1034:
1029:
1022:
1019:
1013:
1010:
996:
995:
982:
976:
972:
968:
965:
960:
957:
953:
949:
944:
940:
936:
933:
928:
925:
921:
916:
912:
906:
903:
897:
894:
880:
879:
865:
859:
855:
851:
848:
843:
840:
836:
832:
827:
823:
819:
816:
811:
808:
804:
799:
792:
789:
783:
779:
773:
770:
766:
762:
757:
754:
750:
745:
738:
735:
729:
726:
712:
711:
699:
679:
669:
656:
646:
631:
628:
624:
600:
597:
593:
582:
567:
564:
560:
536:
533:
529:
518:
503:
500:
496:
472:
469:
465:
454:
439:
435:
411:
407:
380:
377:
373:
349:
345:
321:
318:
314:
290:
286:
271:control volume
254:
251:
236:
233:
223:
220:
190:
187:
184:
183:
180:
177:
172:
168:
167:
164:
161:
156:
152:
151:
148:
145:
142:
138:
137:
134:
131:
128:
119:rocket engines
89:mass flow rate
74:electric motor
54:gas compressor
26:
24:
14:
13:
10:
9:
6:
4:
3:
2:
4923:
4912:
4909:
4908:
4906:
4891:
4888:
4886:
4883:
4881:
4878:
4876:
4873:
4871:
4868:
4867:
4865:
4863:Other systems
4861:
4855:
4852:
4850:
4847:
4846:
4844:
4840:and induction
4839:
4835:
4829:
4826:
4824:
4821:
4819:
4816:
4814:
4811:
4810:
4808:
4806:
4802:
4796:
4795:Glass cockpit
4793:
4791:
4788:
4786:
4783:
4781:
4778:
4776:
4773:
4771:
4768:
4767:
4765:
4759:
4749:
4746:
4744:
4741:
4739:
4736:
4734:
4731:
4729:
4726:
4724:
4721:
4719:
4716:
4714:
4711:
4710:
4708:
4704:
4698:
4695:
4693:
4690:
4689:
4687:
4683:
4680:
4678:
4674:
4664:
4661:
4659:
4656:
4654:
4651:
4649:
4646:
4644:
4641:
4639:
4636:
4634:
4631:
4629:
4626:
4624:
4621:
4619:
4616:
4614:
4611:
4609:
4606:
4604:
4601:
4599:
4596:
4594:
4593:Brayton cycle
4591:
4589:
4586:
4584:
4581:
4580:
4578:
4574:
4568:
4567:Turbine blade
4565:
4563:
4560:
4558:
4555:
4553:
4550:
4548:
4545:
4543:
4540:
4538:
4535:
4533:
4530:
4528:
4525:
4523:
4520:
4519:
4517:
4511:
4505:
4502:
4500:
4497:
4495:
4492:
4490:
4487:
4485:
4482:
4480:
4477:
4475:
4472:
4470:
4467:
4465:
4462:
4460:
4456:
4453:
4451:
4448:
4447:
4445:
4441:
4438:
4436:
4431:
4427:
4423:
4420:
4416:
4409:
4404:
4402:
4397:
4395:
4390:
4389:
4386:
4379:
4378:0-13-312000-7
4375:
4371:
4368:
4367:0-07-145369-5
4364:
4360:
4357:
4356:0-262-11162-4
4353:
4349:
4346:
4345:0-201-14659-2
4342:
4338:
4336:
4332:
4328:
4327:
4323:
4314:
4308:
4305:
4300:
4296:
4290:
4287:
4283:
4278:
4276:
4272:
4267:
4260:
4254:
4251:
4246:
4239:
4233:
4230:
4225:
4221:
4217:
4213:
4206:
4203:
4198:
4191:
4185:
4182:
4177:
4173:
4169:
4165:
4158:
4155:
4151:
4150:0-07-142294-3
4147:
4141:
4138:
4133:
4126:
4124:
4120:
4115:
4109:
4105:
4098:
4096:
4092:
4085:
4080:
4077:
4074:
4071:
4068:
4065:
4062:
4059:
4056:
4053:
4052:
4048:
4046:
4044:
4039:
4033:
4031:
4027:
4020:
4018:
4016:
4012:
4008:
4003:
4000:
3993:
3988:
3986:
3984:
3978:
3976:
3972:
3967:
3965:
3961:
3954:
3946:
3944:
3942:
3938:
3934:
3916:
3909:
3907:
3904:
3901:
3896:
3894:
3890:
3886:
3880:
3873:
3872:Olympus BOl.1
3868:
3861:
3859:
3857:
3852:
3847:
3841:
3839:
3835:
3831:
3827:
3823:
3819:
3815:
3811:
3807:
3803:
3799:
3795:
3791:
3787:
3783:
3782:Metrovick F.2
3779:
3775:
3770:
3768:
3767:superchargers
3764:
3760:
3756:
3755:Frank Whittle
3752:
3748:
3744:
3740:
3739:metal fatigue
3735:
3733:
3729:
3725:
3721:
3717:
3712:
3709:
3705:
3697:
3692:
3689:
3685:
3682:
3681:
3677:
3675:
3671:
3666:
3658:
3656:
3652:
3646:
3643:
3640:
3636:
3633:
3632:
3631:
3624:
3622:
3618:
3601:
3597:
3573:
3569:
3565:
3559:
3556:
3544:
3537:
3535:
3533:
3524:
3517:
3515:
3492:
3486:
3483:
3477:
3474:
3470:
3467:
3461:
3457:
3454:
3451:
3448:
3446:
3441:
3430:
3424:
3421:
3418:
3415:
3413:
3408:
3397:
3396:
3395:
3393:
3392:
3382:
3379:
3377:
3356:
3353:
3347:
3344:
3340:
3337:
3331:
3329:
3324:
3312:
3309:
3302:
3299:
3296:
3293:
3291:
3285:
3282:
3270:
3269:
3266:
3242:
3238:
3234:
3231:
3228:
3223:
3219:
3215:
3212:
3209:
3206:
3199:
3198:
3197:
3180:
3176:
3152:
3148:
3144:
3139:
3135:
3108:
3104:
3100:
3097:
3094:
3089:
3085:
3081:
3078:
3068:The value of
3046:
3042:
3038:
3035:
3032:
3027:
3023:
3019:
3016:
3010:
3007:
3004:
3001:
2998:
2991:
2990:
2989:
2982:
2979:
2977:
2960:
2956:
2952:
2949:
2946:
2941:
2938:
2933:
2928:
2924:
2920:
2917:
2910:
2909:
2902:
2899:
2897:
2877:
2873:
2869:
2866:
2863:
2858:
2854:
2850:
2847:
2841:
2838:
2835:
2828:
2827:
2824:
2804:
2783:
2774:
2767:
2765:
2763:
2758:
2743:
2722:
2715:coefficient (
2714:
2713:stage loading
2709:
2705:
2703:
2695:
2693:
2687:Instabilities
2686:
2680:
2673:
2651:
2646:
2642:
2638:
2633:
2628:
2624:
2620:
2615:
2610:
2607:
2603:
2599:
2594:
2589:
2586:
2582:
2574:
2569:
2566:
2562:
2558:
2553:
2548:
2545:
2541:
2534:
2531:
2524:
2523:
2522:
2496:
2492:
2488:
2482:
2477:
2474:
2470:
2464:
2456:
2452:
2448:
2442:
2437:
2434:
2430:
2424:
2422:
2415:
2411:
2407:
2402:
2398:
2388:
2383:
2378:
2375:
2371:
2365:
2360:
2355:
2350:
2347:
2343:
2337:
2335:
2328:
2324:
2320:
2315:
2311:
2302:
2297:
2291:
2286:
2281:
2277:
2271:
2266:
2261:
2256:
2252:
2245:
2241:
2236:
2232:
2228:
2223:
2219:
2214:
2207:
2204:
2198:
2196:
2191:
2183:
2178:
2169:
2165:
2161:
2155:
2150:
2146:
2140:
2135:
2131:
2126:
2122:
2114:
2110:
2106:
2100:
2095:
2091:
2085:
2080:
2076:
2071:
2065:
2061:
2054:
2051:
2045:
2043:
2038:
2026:
2022:
2018:
2013:
2009:
2001:
1997:
1993:
1988:
1984:
1977:
1975:
1970:
1959:
1958:
1957:
1955:
1951:
1947:
1924:
1921:
1918:
1914:
1908:
1903:
1897:
1893:
1889:
1886:
1881:
1878:
1874:
1870:
1865:
1861:
1857:
1854:
1849:
1846:
1842:
1837:
1828:
1824:
1818:
1814:
1808:
1799:
1792:
1789:
1785:
1780:
1773:
1769:
1752:
1748:
1734:
1733:
1732:
1710:
1707:
1704:
1700:
1694:
1686:
1682:
1665:
1661:
1654:
1645:
1638:
1635:
1631:
1626:
1619:
1615:
1598:
1594:
1580:
1579:
1578:
1559:
1555:
1552:
1545:
1542:
1539:
1535:
1529:
1522:
1518:
1512:
1508:
1502:
1496:
1490:
1486:
1482:
1477:
1473:
1469:
1464:
1460:
1452:
1451:
1450:
1448:
1428:
1422:
1418:
1414:
1411:
1406:
1403:
1399:
1395:
1390:
1386:
1382:
1379:
1374:
1371:
1367:
1362:
1354:
1350:
1346:
1341:
1326:
1322:
1315:
1308:
1307:
1306:
1287:
1281:
1277:
1273:
1268:
1264:
1259:
1253:
1249:
1242:
1239:
1233:
1229:
1223:
1219:
1215:
1212:
1207:
1204:
1200:
1196:
1191:
1187:
1183:
1180:
1175:
1172:
1168:
1163:
1159:
1153:
1150:
1144:
1141:
1134:
1133:
1132:
1113:
1107:
1103:
1099:
1094:
1090:
1085:
1079:
1075:
1068:
1065:
1059:
1055:
1049:
1045:
1041:
1036:
1032:
1027:
1020:
1017:
1011:
1008:
1001:
1000:
999:
980:
974:
970:
966:
963:
958:
955:
951:
947:
942:
938:
934:
931:
926:
923:
919:
914:
910:
904:
901:
895:
892:
885:
884:
883:
863:
857:
853:
849:
846:
841:
838:
834:
830:
825:
821:
817:
814:
809:
806:
802:
797:
790:
787:
781:
777:
771:
768:
764:
760:
755:
752:
748:
743:
736:
733:
727:
724:
717:
716:
715:
697:
677:
670:
654:
647:
629:
626:
622:
598:
595:
591:
583:
565:
562:
558:
534:
531:
527:
519:
501:
498:
494:
470:
467:
463:
455:
437:
433:
409:
405:
397:
396:
395:
378:
375:
371:
347:
343:
319:
316:
312:
288:
284:
274:
272:
268:
259:
252:
250:
246:
243:
234:
232:
230:
229:turbomachines
221:
219:
217:
212:
203:
200:
195:
188:
181:
178:
176:
173:
170:
169:
165:
162:
160:
157:
154:
153:
149:
146:
143:
140:
139:
135:
132:
129:
126:
125:
122:
120:
117:
113:
109:
105:
104:blast furnace
101:
97:
92:
90:
86:
81:
79:
75:
69:
67:
63:
59:
55:
51:
43:
38:
33:
19:
4849:Flame holder
4823:Thrust lever
4813:Autothrottle
4643:Thrust lapse
4598:Bypass ratio
4536:
4430:Gas turbines
4422:gas turbines
4324:Bibliography
4307:
4294:
4289:
4265:
4253:
4244:
4232:
4215:
4211:
4205:
4196:
4184:
4167:
4163:
4157:
4140:
4103:
4040:
4037:
4028:
4024:
4004:
4001:
3997:
3989:Design notes
3979:
3970:
3968:
3956:
3932:
3929:
3905:
3897:
3881:
3877:
3856:streamlining
3842:
3834:Westinghouse
3810:Arado Ar 234
3771:
3736:
3713:
3701:
3672:
3668:
3653:
3650:
3628:
3619:
3545:
3541:
3531:
3529:
3513:
3389:
3387:
3380:
3264:
3067:
2987:
2980:
2900:
2821:
2759:
2710:
2706:
2699:
2690:
2520:
1953:
1945:
1944:
1730:
1576:
1446:
1445:
1304:
1130:
997:
881:
713:
275:
264:
247:
238:
225:
207:
130:Type of flow
96:gas turbines
93:
82:
70:
49:
47:
4763:instruments
4718:Blade pitch
4713:Autofeather
4415:Jet engines
4011:Mach number
3885:heat engine
3698:Development
3538:Surge cycle
3261:is constant
2521:Therefore,
1577:Therefore,
1131:Therefore,
265:The law of
216:Mach number
189:Description
106:air, fluid
100:jet engines
4706:Principles
4685:Components
4677:Propellers
4576:Principles
4527:Air intake
4515:components
4513:Mechanical
4489:Turboshaft
4086:References
3951:See also:
3822:a pure jet
3688:vibrations
3663:See also:
3532:surge line
1676:isentropic
1337:isentropic
242:polytropic
175:Supersonic
141:Industrial
87:and large
85:efficiency
18:Axial flow
4738:Proprotor
4588:Bleed air
4547:Combustor
4484:Turboprop
4079:Turbopump
3999:designs.
3953:Bleed air
3933:two-spool
3874:turbojet.
3778:turboprop
3560:˙
3484:ϕ
3475:ψ
3471:−
3458:ϕ
3455:−
3442:ψ
3431:ϕ
3422:−
3409:ψ
3354:ϕ
3345:ψ
3341:−
3310:ϕ
3300:−
3283:ψ
3239:α
3235:
3220:β
3216:
3177:α
3149:α
3136:α
3105:α
3101:
3086:β
3082:
3043:α
3039:
3024:β
3020:
3011:ϕ
3008:−
2999:ψ
2957:β
2953:
2947:−
2942:ϕ
2925:α
2921:
2874:α
2870:
2864:−
2855:α
2851:
2842:ϕ
2836:ψ
2805:ϕ
2784:ψ
2744:ϕ
2723:ψ
2639:−
2600:−
2559:−
2465:−
2408:−
2366:−
2321:−
2272:−
2229:−
2208:˙
2123:−
2055:˙
2019:−
1994:−
1922:−
1919:γ
1915:γ
1894:α
1890:
1871:−
1862:α
1858:
1800:η
1708:−
1705:γ
1701:γ
1655:δ
1646:η
1553:−
1543:−
1540:γ
1536:γ
1470:−
1419:α
1415:
1396:−
1387:α
1383:
1316:δ
1274:−
1243:˙
1220:α
1216:
1197:−
1188:α
1184:
1154:˙
1100:−
1069:˙
1042:−
1021:˙
971:α
967:
948:−
939:α
935:
905:˙
854:α
850:
831:−
822:α
818:
791:˙
761:−
737:˙
698:β
678:α
211:diffusion
159:Transonic
155:Aerospace
116:aerospace
108:catalytic
4905:Category
4854:Jet fuel
4743:Scimitar
4613:Flameout
4557:Impeller
4479:Turbojet
4474:Turbofan
4455:Pulsejet
4419:aircraft
4049:See also
4030:speeds.
4015:turbofan
3826:Northrop
3814:Lockheed
3794:Jumo 004
3728:airfoils
3625:Stalling
3487:′
3478:′
3357:′
3348:′
3313:′
3286:′
1950:pressure
171:Research
163:1.15–1.6
147:1.05–1.2
144:Subsonic
98:such as
4842:systems
4469:Propfan
3960:turbine
3830:US Navy
3802:BMW 003
3790:Junkers
3724:stalled
3686:Forced
3678:Effects
3639:suction
3518:Surging
222:Working
182:75–85%
179:1.8–2.2
166:80–85%
150:88–92%
62:airfoil
42:stators
4761:Engine
4638:Thrust
4499:Rocket
4494:Ramjet
4376:
4365:
4354:
4343:
4333:
4148:
4110:
3910:Spools
3796:) and
3786:He 178
3743:stress
1763:actual
1609:actual
235:Design
4443:Types
4262:(PDF)
4241:(PDF)
4193:(PDF)
3922:and N
3900:stall
3391:eq. 3
1804:stage
1650:stage
78:steam
76:or a
52:is a
4838:Fuel
4433:and
4417:and
4374:ISBN
4363:ISBN
4352:ISBN
4341:ISBN
4331:ISBN
4146:ISBN
4108:ISBN
3816:and
3757:and
3741:and
614:and
550:and
486:and
425:and
4220:doi
4216:112
4172:doi
3838:J30
3798:BMW
3394:):
3381:(3)
3232:tan
3213:tan
3098:tan
3079:tan
3036:tan
3017:tan
2981:(2)
2950:tan
2918:tan
2901:(1)
2867:tan
2848:tan
1887:tan
1855:tan
1412:tan
1380:tan
1213:tan
1181:tan
964:tan
932:tan
847:tan
815:tan
48:An
4907::
4297:.
4274:^
4264:.
4243:.
4214:.
4195:.
4168:98
4166:.
4122:^
4094:^
3887:,
3840:.
3734:.
2757:)
2027:01
2014:02
1956:.
1819:01
1774:01
1753:02
1687:01
1620:01
1599:02
1449:,
1282:01
1269:02
1108:01
1095:02
1050:01
1037:02
394:.
4457:/
4407:e
4400:t
4393:v
4380:.
4369:.
4358:.
4347:.
4315:.
4268:.
4247:.
4226:.
4222::
4199:.
4178:.
4174::
4152:.
4134:.
4116:.
3924:2
3920:1
3800:(
3792:(
3602:H
3598:P
3574:D
3570:P
3566:,
3557:m
3493:)
3468:1
3462:(
3452:1
3449:=
3434:)
3428:(
3425:J
3419:1
3416:=
3338:1
3332:=
3325:J
3317:)
3306:(
3303:J
3297:1
3294:=
3248:)
3243:3
3229:+
3224:2
3210:=
3207:J
3181:3
3153:3
3145:=
3140:1
3114:)
3109:1
3095:+
3090:2
3076:(
3052:)
3047:1
3033:+
3028:2
3014:(
3005:1
3002:=
2961:2
2939:1
2934:=
2929:2
2883:)
2878:1
2859:2
2845:(
2839:=
2818:)
2652:2
2647:2
2643:V
2634:2
2629:1
2625:V
2621:+
2616:2
2611:2
2608:r
2604:V
2595:2
2590:1
2587:r
2583:V
2575:2
2570:2
2567:r
2563:V
2554:2
2549:1
2546:r
2542:V
2535:=
2532:R
2497:p
2493:c
2489:2
2483:2
2478:2
2475:r
2471:V
2457:p
2453:c
2449:2
2443:2
2438:1
2435:r
2431:V
2425:=
2416:1
2412:T
2403:2
2399:T
2389:2
2384:2
2379:2
2376:r
2372:V
2361:2
2356:2
2351:1
2348:r
2344:V
2338:=
2329:1
2325:h
2316:2
2312:h
2303:)
2298:]
2292:2
2287:2
2282:1
2278:V
2267:2
2262:2
2257:2
2253:V
2246:[
2242:+
2237:1
2233:h
2224:2
2220:h
2215:(
2205:m
2199:=
2192:P
2184:)
2179:]
2170:p
2166:c
2162:2
2156:2
2151:1
2147:V
2141:+
2136:1
2132:T
2127:[
2115:p
2111:c
2107:2
2101:2
2096:2
2092:V
2086:+
2081:2
2077:T
2072:(
2066:p
2062:c
2052:m
2046:=
2039:P
2023:h
2010:h
2002:1
1998:h
1989:2
1985:h
1978:=
1971:R
1925:1
1909:)
1904:]
1898:1
1882:1
1879:f
1875:V
1866:2
1850:2
1847:f
1843:V
1838:[
1829:p
1825:c
1815:T
1809:U
1793:+
1790:1
1786:(
1781:=
1770:p
1759:)
1749:p
1745:(
1711:1
1695:)
1683:T
1672:)
1666:0
1662:T
1658:(
1639:+
1636:1
1632:(
1627:=
1616:p
1605:)
1595:p
1591:(
1560:)
1556:1
1546:1
1530:]
1523:1
1519:T
1513:2
1509:T
1503:[
1497:(
1491:1
1487:p
1483:=
1478:1
1474:p
1465:2
1461:p
1429:)
1423:1
1407:1
1404:f
1400:V
1391:2
1375:2
1372:f
1368:V
1363:(
1355:p
1351:c
1347:U
1342:=
1333:)
1327:0
1323:T
1319:(
1288:)
1278:T
1265:T
1260:(
1254:p
1250:c
1240:m
1234:=
1230:)
1224:1
1208:1
1205:f
1201:V
1192:2
1176:2
1173:f
1169:V
1164:(
1160:U
1151:m
1145:=
1142:P
1114:)
1104:T
1091:T
1086:(
1080:p
1076:c
1066:m
1060:=
1056:)
1046:h
1033:h
1028:(
1018:m
1012:=
1009:P
981:)
975:1
959:1
956:f
952:V
943:2
927:2
924:f
920:V
915:(
911:U
902:m
896:=
893:P
864:)
858:1
842:1
839:f
835:V
826:2
810:2
807:f
803:V
798:(
788:m
782:=
778:)
772:1
769:w
765:V
756:2
753:w
749:V
744:(
734:m
728:=
725:F
655:U
630:2
627:r
623:V
599:1
596:r
592:V
566:2
563:w
559:V
535:1
532:w
528:V
502:2
499:f
495:V
471:1
468:f
464:V
438:2
434:V
410:1
406:V
379:2
376:w
372:V
348:2
344:r
320:1
317:w
313:V
289:1
285:r
204:.
44:.
20:)
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