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Moody chart

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Moody's team used the available data (including that of Nikuradse) to show that fluid flow in rough pipes could be described by four dimensionless quantities: Reynolds number, pressure loss coefficient, diameter ratio of the pipe and the relative roughness of the pipe. They then produced a single
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The chart's purpose was to provide a graphical representation of the function of C. F. Colebrook in collaboration with C. M. White, which provided a practical form of transition curve to bridge the transition zone between smooth and rough pipes, the region of incomplete turbulence.
821: 421: 1087: 724: 294: 344: 782: 596: 946:{\displaystyle {1 \over {\sqrt {f_{D}}}}=-2.0\log _{10}\left({\frac {\epsilon /D}{3.7}}+{\frac {2.51}{\mathrm {Re} {\sqrt {f_{D}}}}}\right),{\text{for turbulent flow}}.} 157: 1015: 813: 754: 660: 564: 491: 444: 215: 184: 630: 987: 531: 511: 464: 136:
plot which showed that all of these collapsed onto a series of lines, now known as the Moody chart. This dimensionless chart is used to work out pressure drop,
119:, whose work was based upon an analysis of some 10,000 experiments from various sources. Measurements of fluid flow in artificially roughened pipes by 1139: 355: 1023: 672: 223: 1121: 1259: 570:
Re for a variety of relative roughnesses, the ratio of the mean height of roughness of the pipe to the pipe diameter or
187: 92: 36: 1223:"Turbulent Flow in Pipes, With Particular Reference to the Transition Region Between the Smooth and Rough Pipe Laws" 305: 1194: 1274: 966: 633: 537: 32: 962: 1279: 785: 759: 573: 139: 100: 88: 52: 1234: 1222: 120: 993: 791: 732: 638: 542: 469: 429: 193: 162: 59:
in a circular pipe. It can be used to predict pressure drop or flow rate down such a pipe.
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These show in detail the transition region for pipes with high relative roughness (ε /
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plotted against Reynolds number Re for various relative roughness ε / 
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For the turbulent flow regime, the relationship between the friction factor
56: 1144:. Proceedings Second Hydraulic Conference, University of Iowa Bulletin 27. 632:< ~3000), roughness has no discernible effect, and the Darcy–Weisbach 1174:
Kemler, E. (1933). "A Study of the Data on the Flow of Fluid in Pipes".
186:(m)) and flow rate through pipes. Head loss can be calculated using the 416:{\displaystyle \Delta p=f_{D}{\frac {\rho V^{2}}{2}}{\frac {L}{D}},} 62: 1155:
Pigott, R. J. S. (1933). "The Flow of Fluids in Closed Conduits".
1082:{\displaystyle \Delta p={\frac {\rho V^{2}}{2}}{\frac {4fL}{D}},} 719:{\displaystyle f_{D}=64/\mathrm {Re} ,{\text{for laminar flow}}.} 289:{\displaystyle h_{f}=f_{D}{\frac {L}{D}}{\frac {V^{2}}{2\,g}};} 115:
but uses the more practical choice of coordinates employed by
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were at the time too recent to include in Pigott's chart.
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The Moody chart can be divided into two regimes of flow:
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Moody diagram showing the Darcy–Weisbach friction factor
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is more complex. One model for this relationship is the
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the Reynolds number Re, and the relative roughness
1081: 1009: 981: 945: 807: 776: 748: 718: 654: 624: 590: 558: 525: 505: 485: 458: 438: 415: 338: 288: 209: 178: 151: 1227:Journal of the Institution of Civil Engineers 493:is the friction factor from the Moody chart, 8: 961:This formula must not be confused with the 107:. This chart became commonly known as the 1058: 1046: 1036: 1025: 1001: 995: 974: 935: 916: 910: 902: 896: 879: 873: 859: 836: 830: 825: 823: 799: 793: 766: 761: 740: 734: 708: 697: 692: 680: 674: 646: 640: 614: 580: 575: 550: 544: 518: 498: 477: 471: 451: 431: 400: 388: 378: 372: 357: 330: 325: 321: 307: 276: 266: 260: 250: 244: 231: 225: 201: 195: 170: 164: 141: 111:or Moody diagram. It adapts the work of 339:{\displaystyle \Delta p=\rho \,g\,h_{f}} 299:Pressure drop can then be evaluated as: 61: 1097: 466:is the average velocity in the pipe, 7: 190:in which the Darcy friction factor 1195:"Strömungsgesetze in Rauen Rohren" 1027: 906: 903: 788:(which is an implicit equation in 701: 698: 359: 309: 143: 99:Re for various values of relative 14: 1141:Evaluation of Boundary Roughness 1107:"Friction factors for pipe flow" 1233:(4). London, England: 133–156. 1127:from the original on 2019-11-26 662:was determined analytically by 609:. For the laminar flow regime ( 536:The chart plots Darcy–Weisbach 1260:Darcy friction factor formulae 1221:Colebrook, C. F. (1938–1939). 513:is the length of the pipe and 93:Darcy–Weisbach friction factor 37:Darcy–Weisbach friction factor 1: 1017:. Here the pressure drop is: 446:is the density of the fluid, 16:Graph used in fluid dynamics 777:{\displaystyle \epsilon /D} 591:{\displaystyle \epsilon /D} 1301: 1239:10.1680/ijoti.1939.13150 1176:Transactions of the ASME 1114:Transactions of the ASME 152:{\displaystyle \Delta p} 1199:V. D. I. Forschungsheft 967:Fanning friction factor 957:Fanning friction factor 188:Darcy–Weisbach equation 1193:Nikuradse, J. (1933). 1157:Mechanical Engineering 1083: 1011: 983: 947: 809: 778: 750: 720: 656: 626: 592: 560: 533:is the pipe diameter. 527: 507: 487: 460: 440: 417: 340: 290: 211: 180: 153: 79: 35:form that relates the 1105:Moody, L. F. (1944), 1084: 1012: 1010:{\displaystyle f_{D}} 984: 948: 810: 808:{\displaystyle f_{D}} 779: 751: 749:{\displaystyle f_{D}} 721: 657: 655:{\displaystyle f_{D}} 627: 593: 561: 559:{\displaystyle f_{D}} 528: 508: 488: 486:{\displaystyle f_{D}} 461: 441: 439:{\displaystyle \rho } 418: 341: 291: 212: 210:{\displaystyle f_{D}} 181: 179:{\displaystyle h_{f}} 154: 65: 1024: 994: 973: 822: 792: 760: 733: 673: 639: 613: 574: 543: 517: 497: 470: 450: 430: 356: 306: 224: 194: 163: 159:(Pa) (or head loss, 140: 55:for fully developed 19:In engineering, the 1138:Rouse, H. (1943). 1079: 1007: 979: 943: 937:for turbulent flow 805: 786:Colebrook equation 774: 746: 716: 652: 625:{\displaystyle Re} 622: 588: 556: 523: 503: 483: 456: 436: 413: 336: 286: 207: 176: 149: 80: 1182:(Hyd-55-2): 7–32. 1074: 1056: 982:{\displaystyle f} 938: 925: 922: 891: 844: 842: 711: 526:{\displaystyle D} 506:{\displaystyle L} 459:{\displaystyle V} 408: 398: 349:or directly from 281: 258: 89:Lewis Ferry Moody 53:surface roughness 1292: 1243: 1242: 1218: 1212: 1206: 1190: 1184: 1183: 1171: 1165: 1164: 1152: 1146: 1145: 1135: 1129: 1128: 1126: 1111: 1102: 1088: 1086: 1085: 1080: 1075: 1070: 1059: 1057: 1052: 1051: 1050: 1037: 1016: 1014: 1013: 1008: 1006: 1005: 988: 986: 985: 980: 963:Fanning equation 952: 950: 949: 944: 939: 936: 931: 927: 926: 924: 923: 921: 920: 911: 909: 897: 892: 887: 883: 874: 864: 863: 845: 843: 841: 840: 831: 826: 814: 812: 811: 806: 804: 803: 783: 781: 780: 775: 770: 755: 753: 752: 747: 745: 744: 725: 723: 722: 717: 712: 710:for laminar flow 709: 704: 696: 685: 684: 661: 659: 658: 653: 651: 650: 631: 629: 628: 623: 597: 595: 594: 589: 584: 565: 563: 562: 557: 555: 554: 532: 530: 529: 524: 512: 510: 509: 504: 492: 490: 489: 484: 482: 481: 465: 463: 462: 457: 445: 443: 442: 437: 422: 420: 419: 414: 409: 401: 399: 394: 393: 392: 379: 377: 376: 345: 343: 342: 337: 335: 334: 295: 293: 292: 287: 282: 280: 271: 270: 261: 259: 251: 249: 248: 236: 235: 216: 214: 213: 208: 206: 205: 185: 183: 182: 177: 175: 174: 158: 156: 155: 150: 31:) is a graph in 1300: 1299: 1295: 1294: 1293: 1291: 1290: 1289: 1265: 1264: 1251: 1246: 1220: 1219: 1215: 1205:. Berlin: 1–22. 1192: 1191: 1187: 1173: 1172: 1168: 1163:: 497–501, 515. 1154: 1153: 1149: 1137: 1136: 1132: 1124: 1109: 1104: 1103: 1099: 1095: 1060: 1042: 1038: 1022: 1021: 997: 992: 991: 971: 970: 959: 912: 901: 875: 872: 868: 855: 832: 820: 819: 795: 790: 789: 758: 757: 736: 731: 730: 676: 671: 670: 642: 637: 636: 634:friction factor 611: 610: 572: 571: 568:Reynolds number 546: 541: 540: 538:friction factor 515: 514: 495: 494: 473: 468: 467: 448: 447: 428: 427: 384: 380: 368: 354: 353: 326: 304: 303: 272: 262: 240: 227: 222: 221: 217:appears : 197: 192: 191: 166: 161: 160: 138: 137: 133: 117:R. J. S. Pigott 97:Reynolds number 85: 74: 49:Reynolds number 46: 33:non-dimensional 29:Stanton diagram 17: 12: 11: 5: 1298: 1296: 1288: 1287: 1282: 1277: 1275:Fluid dynamics 1267: 1266: 1263: 1262: 1257: 1250: 1247: 1245: 1244: 1213: 1185: 1166: 1147: 1130: 1120:(8): 671–684, 1096: 1094: 1091: 1090: 1089: 1078: 1073: 1069: 1066: 1063: 1055: 1049: 1045: 1041: 1035: 1032: 1029: 1004: 1000: 978: 958: 955: 954: 953: 942: 934: 930: 919: 915: 908: 905: 900: 895: 890: 886: 882: 878: 871: 867: 862: 858: 854: 851: 848: 839: 835: 829: 802: 798: 773: 769: 765: 743: 739: 727: 726: 715: 707: 703: 700: 695: 691: 688: 683: 679: 649: 645: 621: 618: 587: 583: 579: 553: 549: 522: 502: 480: 476: 455: 435: 424: 423: 412: 407: 404: 397: 391: 387: 383: 375: 371: 367: 364: 361: 347: 346: 333: 329: 324: 320: 317: 314: 311: 297: 296: 285: 279: 275: 269: 265: 257: 254: 247: 243: 239: 234: 230: 204: 200: 173: 169: 148: 145: 132: 129: 84: 81: 70: 42: 15: 13: 10: 9: 6: 4: 3: 2: 1297: 1286: 1283: 1281: 1278: 1276: 1273: 1272: 1270: 1261: 1258: 1256: 1255:Friction loss 1253: 1252: 1248: 1240: 1236: 1232: 1228: 1224: 1217: 1214: 1210: 1204: 1200: 1196: 1189: 1186: 1181: 1177: 1170: 1167: 1162: 1158: 1151: 1148: 1143: 1142: 1134: 1131: 1123: 1119: 1115: 1108: 1101: 1098: 1092: 1076: 1071: 1067: 1064: 1061: 1053: 1047: 1043: 1039: 1033: 1030: 1020: 1019: 1018: 1002: 998: 989: 976: 968: 964: 956: 940: 932: 928: 917: 913: 898: 893: 888: 884: 880: 876: 869: 865: 860: 856: 852: 849: 846: 837: 833: 827: 818: 817: 816: 800: 796: 787: 771: 767: 763: 741: 737: 713: 705: 693: 689: 686: 681: 677: 669: 668: 667: 665: 647: 643: 635: 619: 616: 608: 604: 599: 585: 581: 577: 569: 551: 547: 539: 534: 520: 500: 478: 474: 453: 433: 410: 405: 402: 395: 389: 385: 381: 373: 369: 365: 362: 352: 351: 350: 331: 327: 322: 318: 315: 312: 302: 301: 300: 283: 277: 273: 267: 263: 255: 252: 245: 241: 237: 232: 228: 220: 219: 218: 202: 198: 189: 171: 167: 146: 130: 128: 124: 122: 118: 114: 110: 106: 102: 98: 94: 90: 82: 78: 73: 69: 64: 60: 58: 54: 50: 45: 41: 38: 34: 30: 26: 25:Moody diagram 22: 1230: 1226: 1216: 1211:> 0.001). 1208: 1202: 1198: 1188: 1179: 1175: 1169: 1160: 1156: 1150: 1140: 1133: 1117: 1113: 1100: 969: 965:, using the 960: 728: 600: 535: 425: 348: 298: 134: 125: 121:J. Nikuradse 113:Hunter Rouse 108: 104: 91:plotted the 86: 76: 71: 67: 43: 39: 28: 24: 20: 18: 131:Description 109:Moody chart 21:Moody chart 1280:Hydraulics 1269:Categories 1093:References 664:Poiseuille 1040:ρ 1028:Δ 877:ϵ 866:⁡ 850:− 764:ϵ 607:turbulent 578:ϵ 434:ρ 382:ρ 360:Δ 319:ρ 310:Δ 144:Δ 101:roughness 87:In 1944, 1249:See also 1122:archived 566:against 95:against 51:Re, and 603:laminar 83:History 1285:Piping 426:where 27:(also 1125:(PDF) 1110:(PDF) 899:2.51 605:and 103:ε / 57:flow 1235:doi 1203:361 889:3.7 857:log 853:2.0 815:): 23:or 1271:: 1231:11 1229:. 1225:. 1201:. 1197:. 1180:55 1178:. 1161:55 1159:. 1118:66 1116:, 1112:, 861:10 690:64 666:: 598:. 47:, 1241:. 1237:: 1209:D 1077:, 1072:D 1068:L 1065:f 1062:4 1054:2 1048:2 1044:V 1034:= 1031:p 1003:D 999:f 977:f 941:. 933:, 929:) 918:D 914:f 907:e 904:R 894:+ 885:D 881:/ 870:( 847:= 838:D 834:f 828:1 801:D 797:f 772:D 768:/ 742:D 738:f 714:. 706:, 702:e 699:R 694:/ 687:= 682:D 678:f 648:D 644:f 620:e 617:R 586:D 582:/ 552:D 548:f 521:D 501:L 479:D 475:f 454:V 411:, 406:D 403:L 396:2 390:2 386:V 374:D 370:f 366:= 363:p 332:f 328:h 323:g 316:= 313:p 284:; 278:g 274:2 268:2 264:V 256:D 253:L 246:D 242:f 238:= 233:f 229:h 203:D 199:f 172:f 168:h 147:p 105:D 77:D 72:D 68:f 44:D 40:f

Index

non-dimensional
Darcy–Weisbach friction factor
Reynolds number
surface roughness
flow

Lewis Ferry Moody
Darcy–Weisbach friction factor
Reynolds number
roughness
Hunter Rouse
R. J. S. Pigott
J. Nikuradse
Darcy–Weisbach equation
friction factor
Reynolds number
laminar
turbulent
friction factor
Poiseuille
Colebrook equation
Fanning equation
Fanning friction factor
"Friction factors for pipe flow"
archived
Evaluation of Boundary Roughness
"Strömungsgesetze in Rauen Rohren"
"Turbulent Flow in Pipes, With Particular Reference to the Transition Region Between the Smooth and Rough Pipe Laws"
doi
10.1680/ijoti.1939.13150

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