25:
565:
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
1059:
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
953:
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
1168:
408:
1211:
1070:
950:
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).
301:
1175:
453:
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
583:
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.
506:
443:
1126:
563:
239:
208:
173:
526:
309:
1232:
958:). Combustion equipment is typically designed to burn a fuel gas within a particular family: hydrogen-rich town gas, natural gas or LPG.
450:
1133:
1110:
247:
89:
61:
566:
will also be identical. Typically variations of up to 5% are allowed as these would not be noticeable to the consumer.
971:
935:
637:
614:
446:
108:
68:
1047:
Other flame characteristics and composition limits may determine the acceptability of the replacement gas, e.g.
46:
75:
42:
609:
Note that these Wobbe numbers below are not calculated at 15 °C and so are not correct according to
569:
The Wobbe index is a critical factor to minimise the impact of the changeover when analyzing the use of
57:
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8:
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145:
and is frequently defined in the specifications of gas supply and transport utilities.
1051:, "yellow tipping" due to incomplete combustion, sulfur content, oxygen content, etc.
1257:
1226:
1106:
1095:
1088:
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211:
1083:
885:
403:{\displaystyle G_{S}={\frac {\rho _{STP}}{\rho _{air,STP}}}={\frac {M}{M_{air}}}}
180:
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1005:
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938:(where 'Nm³' indicates'm³ in Normal conditions), or sometimes in
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469:
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296:{\displaystyle I_{W}={\frac {V_{C}}{\sqrt {G_{S}}}}.}
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1071:"The Wobbe Index and Natural Gas Interchangeability"
593:
586:The Wobbe index has its origins in the 1920's with
49:. Unsourced material may be challenged and removed.
1210:Flórez-Orrego, Daniel, Escola Politécnica da USP.
557:
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16:Indicator of the interchangeability of fuel gases
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508:is the density of air at standard conditions,
129:is an indicator of the interchangeability of
1231:: CS1 maint: multiple names: authors list (
1076:. Emerson Process Management. 2007-07-30.
109:Learn how and when to remove this message
590:physicist and engineer Goffredo Wobbe.
1245:
47:adding citations to reliable sources
18:
13:
14:
1274:
615:Standard temperature and pressure
930:The Wobbe index is expressed in
594:Wobbe index of common fuel gases
23:
501:{\displaystyle \rho _{air,STP}}
34:needs additional citations for
1203:
1192:
1161:
1150:
1119:
1054:
946:. In the case of natural gas (
1:
1212:"Fuel Gas Interchangeability"
1063:
445:is the density of the gas at
7:
1097:Gas Installation Technology
438:{\displaystyle \rho _{STP}}
10:
1279:
1199:Wobbe Index and Fuel Gases
1169:"American Gas Association"
925:
558:{\displaystyle M_{air}}
139:liquefied petroleum gas
1093:Treloar, R.D. (2005).
970:Wobbe index range (MJ/
572:substitute natural gas
559:
522:
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1101:. Blackwell. p.
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234:{\displaystyle I_{W}}
205:
203:{\displaystyle G_{S}}
170:
168:{\displaystyle V_{C}}
575:(SNG) fuels such as
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177:higher heating value
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43:improve this article
977:Wobbe number range
447:standard conditions
214:, the Wobbe index,
1157:Ingemar Gunnarsson
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1253:Eponymous indices
1112:978-1-4051-1880-4
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521:{\displaystyle M}
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1263:Gas technologies
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1174:. Archived from
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1181:on 2021-12-29
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1139:on 2015-09-23
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1128:
1127:"Bio Gas max"
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99:February 2010
91:
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70:
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63:
60: –
59:
58:"Wobbe index"
55:
54:Find sources:
48:
44:
38:
37:
32:This article
30:
26:
21:
20:
1215:. Retrieved
1205:
1194:
1183:. Retrieved
1176:the original
1163:
1152:
1141:. Retrieved
1134:the original
1121:
1096:
1058:
1046:
1041:72.0 – 87.0
1025:48.0 – 53.0
997:24.0 – 29.0
967:Type of gas
952:
929:
610:
608:
585:
570:
568:
463:
458:
454:
412:
179:, or higher
147:
127:Wobbe number
126:
122:
120:
105:
96:
86:
79:
72:
65:
53:
41:Please help
36:verification
33:
1055:Limitations
1049:flame speed
1038:73.5 – 87.5
1022:45.5 – 55.0
1010:39.0 – 45.0
994:22.5 – 30.0
734:Natural gas
650:Lower index
642:Upper index
634:Lower index
626:Upper index
141:(LPG), and
135:natural gas
123:Wobbe index
1247:Categories
1185:2022-03-01
1143:2012-09-07
1064:References
948:molar mass
829:Butylene-1
810:Iso-butane
530:molar mass
451:definition
131:fuel gases
69:newspapers
867:Acetylene
772:Propylene
611:ISO 13443
472:ρ
455:ISO 13443
421:ρ
346:ρ
330:ρ
1258:Fuel gas
1227:cite web
1060:system.
986:Town gas
916:10
906:Note: 1
791:n-butane
715:Ethylene
658:Hydrogen
623:Fuel gas
459:ISO 6976
143:town gas
133:such as
125:(WI) or
1006:Natural
964:Family
753:Propane
677:Methane
588:Italian
577:propane
528:is the
210:is the
175:is the
83:scholar
1109:
990:Syngas
912:2.3901
899:12.80
880:59.16
874:14,141
871:14,655
861:79.94
855:19,106
852:20,755
842:82.54
836:19,728
833:21,142
823:84.71
817:20,247
814:21,980
804:85.08
798:20,336
795:22,066
785:71.88
779:17,180
776:18,413
766:74.54
760:17,817
757:19,376
747:48.52
741:11,597
738:12,837
728:60.01
722:14,344
719:15,253
709:62.47
703:14,931
700:16,298
696:Ethane
690:47.91
684:11,452
681:12,735
671:40.65
662:11,528
652:MJ/m³
613:, see
598:": -->
449:, the
183:, and
85:
78:
71:
64:
56:
1217:8 Sep
1179:(PDF)
1172:(PDF)
1137:(PDF)
1130:(PDF)
1074:(PDF)
926:Usage
908:Joule
896:12.80
893:3,060
890:3,060
877:61.32
858:86.84
839:88.46
820:91.96
801:92.32
782:77.04
763:81.07
744:53.71
725:63.82
706:68.19
687:53.28
668:48.23
665:9,715
636:kcal/
90:JSTOR
76:books
1233:link
1219:2012
1107:ISBN
918:kcal
631:/Nm³
629:kcal
600:edit
457:and
121:The
62:news
1034:LPG
1017:2 H
1002:2 L
956:LPG
944:scf
940:BTU
936:Nm³
848:LPG
647:/m³
638:Nm³
581:air
148:If
45:by
1249::
1229:}}
1225:{{
1105:.
1103:24
1085:^
988:/
974:)
972:Nm
932:MJ
910:=
645:MJ
617:.
461:.
137:,
1235:)
1221:.
1188:.
1146:.
1115:.
1030:3
982:1
954:(
942:/
934:/
921:.
914:×
604:]
579:-
551:r
548:i
545:a
541:M
516:M
494:P
491:T
488:S
485:,
482:r
479:i
476:a
431:P
428:T
425:S
394:r
391:i
388:a
384:M
380:M
375:=
368:P
365:T
362:S
359:,
356:r
353:i
350:a
340:P
337:T
334:S
324:=
319:S
315:G
291:.
283:S
279:G
272:C
268:V
262:=
257:W
253:I
227:W
223:I
196:S
192:G
161:C
157:V
112:)
106:(
101:)
97:(
87:·
80:·
73:·
66:·
39:.
Text is available under the Creative Commons Attribution-ShareAlike License. Additional terms may apply.
