36:
576:
is the molar mass of air which is about 28.96 kg/kmol. . The Wobbe index is used to compare the combustion energy output of different composition fuel gases in an appliance (fire, cooker etc.). If two fuels have identical Wobbe indices then for given pressure and valve settings the energy output
1070:
In spite of its usefulness, Wobbe index alone is not a good indicator of the interchangeability of two or more gases, or mixtures of them. It is necessary to bear in mind other criteria while determining the plenty substitution of a fuel by other, different of the one used to adjust the burning
964:
There are three ranges or "families" of fuel gases that have been internationally agreed based on Wobbe index. Family 1 covers manufactured gases, family 2 covers natural gases (with high and low ranges) and family 3 covers liquefied petroleum gas
1179:
419:
1222:
1081:
961:
17 g/mol), the typical heating value is around 39 MJ/Nm³ (1,050 BTU/scf) and the specific gravity is approximately 0.59, giving a typical Wobbe index of 51 MJ/Nm³ (1,367 BTU/scf).
312:
1186:
464:
of which changed in 1982. Published Wobbe data may be using 0 °C, 15 °C, 15.56 °C, 20 °C or 25 °C. EU directives on gas quality use 15 °C in accordance with
594:
mixtures. The Wobbe index also requires the addition of propane to some upgraded biomethane products, particularly in regions where natural gas has a high calorific value such as Sweden.
517:
454:
1137:
1243:
574:
250:
219:
184:
537:
320:
1121:
969:). Combustion equipment is typically designed to burn a fuel gas within a particular family: hydrogen-rich town gas, natural gas or LPG.
982:
946:
648:
625:
461:
457:
119:
1144:
57:
258:
100:
72:
53:
577:
will also be identical. Typically variations of up to 5% are allowed as these would not be noticeable to the consumer.
1263:
79:
1273:
1058:
Other flame characteristics and composition limits may determine the acceptability of the replacement gas, e.g.
86:
1044:
966:
858:
149:
46:
582:
620:
Note that these Wobbe numbers below are not calculated at 15 °C and so are not correct according to
580:
The Wobbe index is a critical factor to minimise the impact of the changeover when analyzing the use of
68:
1167:
950:
477:
187:
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1113:
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522:
156:
and is frequently defined in the specifications of gas supply and transport utilities.
1062:, "yellow tipping" due to incomplete combustion, sulfur content, oxygen content, etc.
1257:
1106:
1099:
1097:
414:{\displaystyle G_{S}={\frac {\rho _{STP}}{\rho _{air,STP}}}={\frac {M}{M_{air}}}}
1059:
1016:
744:
145:
35:
958:
839:
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540:
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655:
17:
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725:
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598:
153:
141:
928:
763:
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587:
1000:
706:
918:
949:(where 'Nm³' indicates'm³ in Normal conditions), or sometimes in
591:
29:
549:
525:
480:
429:
323:
307:{\displaystyle I_{W}={\frac {V_{C}}{\sqrt {G_{S}}}}.}
261:
231:
200:
165:
1082:"The Wobbe Index and Natural Gas Interchangeability"
597:The Wobbe index has its origins in the 1920's with
60:. Unsourced material may be challenged and removed.
1221:Flórez-Orrego, Daniel, Escola Politécnica da USP.
568:
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27:Indicator of the interchangeability of fuel gases
519:is the density of air at standard conditions,
140:is an indicator of the interchangeability of
8:
1242:: CS1 maint: multiple names: authors list (
630:
1087:. Emerson Process Management. 2007-07-30.
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120:Learn how and when to remove this message
971:
1093:
601:physicist and engineer Goffredo Wobbe.
1235:
7:
58:adding citations to reliable sources
25:
626:Standard temperature and pressure
941:The Wobbe index is expressed in
605:Wobbe index of common fuel gases
34:
512:{\displaystyle \rho _{air,STP}}
45:needs additional citations for
957:. In the case of natural gas (
1:
1223:"Fuel Gas Interchangeability"
456:is the density of the gas at
1108:Gas Installation Technology
449:{\displaystyle \rho _{STP}}
1290:
1210:Wobbe Index and Fuel Gases
1180:"American Gas Association"
569:{\displaystyle M_{air}}
150:liquefied petroleum gas
1104:Treloar, R.D. (2005).
981:Wobbe index range (MJ/
583:substitute natural gas
570:
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1112:. Blackwell. p.
571:
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247:
245:{\displaystyle I_{W}}
216:
214:{\displaystyle G_{S}}
181:
179:{\displaystyle V_{C}}
586:(SNG) fuels such as
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427:
321:
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188:higher heating value
163:
54:improve this article
988:Wobbe number range
458:standard conditions
225:, the Wobbe index,
1168:Ingemar Gunnarsson
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1264:Eponymous indices
1123:978-1-4051-1880-4
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532:{\displaystyle M}
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252:, is defined as:
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16:(Redirected from
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1274:Gas technologies
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1185:. Archived from
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897:Carbon monoxide
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1192:on 2021-12-29
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1150:on 2015-09-23
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1138:"Bio Gas max"
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110:February 2010
102:
99:
95:
92:
88:
85:
81:
78:
74:
71: –
70:
69:"Wobbe index"
66:
65:Find sources:
59:
55:
49:
48:
43:This article
41:
37:
32:
31:
19:
1226:. Retrieved
1216:
1205:
1194:. Retrieved
1187:the original
1174:
1163:
1152:. Retrieved
1145:the original
1132:
1107:
1069:
1057:
1052:72.0 – 87.0
1036:48.0 – 53.0
1008:24.0 – 29.0
978:Type of gas
963:
940:
621:
619:
596:
581:
579:
474:
469:
465:
423:
190:, or higher
158:
138:Wobbe number
137:
133:
131:
116:
107:
97:
90:
83:
76:
64:
52:Please help
47:verification
44:
1066:Limitations
1060:flame speed
1049:73.5 – 87.5
1033:45.5 – 55.0
1021:39.0 – 45.0
1005:22.5 – 30.0
745:Natural gas
661:Lower index
653:Upper index
645:Lower index
637:Upper index
152:(LPG), and
146:natural gas
134:Wobbe index
18:Wobbe Index
1258:Categories
1196:2022-03-01
1154:2012-09-07
1075:References
959:molar mass
840:Butylene-1
821:Iso-butane
541:molar mass
462:definition
142:fuel gases
80:newspapers
878:Acetylene
783:Propylene
622:ISO 13443
483:ρ
466:ISO 13443
432:ρ
357:ρ
341:ρ
1269:Fuel gas
1238:cite web
1071:system.
997:Town gas
927:10
917:Note: 1
802:n-butane
726:Ethylene
669:Hydrogen
634:Fuel gas
470:ISO 6976
154:town gas
144:such as
136:(WI) or
1017:Natural
975:Family
764:Propane
688:Methane
599:Italian
588:propane
539:is the
221:is the
186:is the
94:scholar
1120:
1001:Syngas
923:2.3901
910:12.80
891:59.16
885:14,141
882:14,655
872:79.94
866:19,106
863:20,755
853:82.54
847:19,728
844:21,142
834:84.71
828:20,247
825:21,980
815:85.08
809:20,336
806:22,066
796:71.88
790:17,180
787:18,413
777:74.54
771:17,817
768:19,376
758:48.52
752:11,597
749:12,837
739:60.01
733:14,344
730:15,253
720:62.47
714:14,931
711:16,298
707:Ethane
701:47.91
695:11,452
692:12,735
682:40.65
673:11,528
663:MJ/m³
624:, see
609:": -->
460:, the
194:, and
96:
89:
82:
75:
67:
1228:8 Sep
1190:(PDF)
1183:(PDF)
1148:(PDF)
1141:(PDF)
1085:(PDF)
937:Usage
919:Joule
907:12.80
904:3,060
901:3,060
888:61.32
869:86.84
850:88.46
831:91.96
812:92.32
793:77.04
774:81.07
755:53.71
736:63.82
717:68.19
698:53.28
679:48.23
676:9,715
647:kcal/
101:JSTOR
87:books
1244:link
1230:2012
1118:ISBN
929:kcal
642:/Nm³
640:kcal
611:edit
468:and
132:The
73:news
1045:LPG
1028:2 H
1013:2 L
967:LPG
955:scf
951:BTU
947:Nm³
859:LPG
658:/m³
649:Nm³
592:air
159:If
56:by
1260::
1240:}}
1236:{{
1116:.
1114:24
1096:^
999:/
985:)
983:Nm
943:MJ
921:=
656:MJ
628:.
472:.
148:,
1246:)
1232:.
1199:.
1157:.
1126:.
1041:3
993:1
965:(
953:/
945:/
932:.
925:×
615:]
590:-
562:r
559:i
556:a
552:M
527:M
505:P
502:T
499:S
496:,
493:r
490:i
487:a
442:P
439:T
436:S
405:r
402:i
399:a
395:M
391:M
386:=
379:P
376:T
373:S
370:,
367:r
364:i
361:a
351:P
348:T
345:S
335:=
330:S
326:G
302:.
294:S
290:G
283:C
279:V
273:=
268:W
264:I
238:W
234:I
207:S
203:G
172:C
168:V
123:)
117:(
112:)
108:(
98:·
91:·
84:·
77:·
50:.
20:)
Text is available under the Creative Commons Attribution-ShareAlike License. Additional terms may apply.
