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Wobbe Index

Reference data and engineering information about wobbe index for miscellaneous applications.

wobbeindex

Overview

Engineering reference data for Wobbe Index in miscellaneous.

Key Formulas

Unit Conversion

y=xky = x \cdot k

Multiply by conversion factor.

Linear Interpolation

y=y1+(xx1)(y2y1)x2x1y = y_1 + \frac{(x - x_1)(y_2 - y_1)}{x_2 - x_1}

Estimate between two known points.

Percentage

p=partwhole×100%p = \frac{\text{part}}{\text{whole}} \times 100\%

Part as fraction of whole.

Variables

SymbolDescriptionUnit
xxInput value
yyOutput value
kkConversion factor

Fuel Gas Wobbe Index Reference Table

13 rows
Wobbe Index values for common fuel gases.
Fuel Gas
Upper Wobbe Index(kcal/Nm³)
Lower Wobbe Index(kcal/Nm³)
Hydrogen115289714
Methane1273511452
Ethane1629814931
Ethylene1525314344
Natural Gas1283711597
Propane1937617814
Propylene1841317180
n-Butane2206620336
Iso-Butane2198020247
Butylene-12114219728
LPG2075519106
Acetylene1465514141
Carbon Monoxide30603060

Source: engineeringtoolbox.com

Important Notes on Application

The Wobbe Index primarily indicates the interchangeability of fuel gases by comparing the energy output per unit volume of air used. It is a key metric for ensuring appliances or turbines can operate safely and efficiently when switching between gas sources of different compositions.

Critical Limitation: The Wobbe Index does not account for differences in flame temperature, heat transfer coefficients, or temperature gradients. It solely addresses volumetric energy flow and air requirement similarity.

Interactive Charts

Wobbe Index values for common fuel gases.

References