Per GPA 2172 & GPA 2145 - Composition-Based Heating Value
Understand GPA 2261 analysis methods, heating value calculations, and gas quality specifications
It calculates heating value, specific gravity, molecular weight, compressibility, and Wobbe Index from gas chromatograph composition data, using the GPA 2172 calculation method with GPA 2145 component constants.
GPA 2172 is the industry standard method for calculating the gross heating value, relative density, and compressibility of a natural gas mixture from its component composition. It uses the summation-factor compressibility Z = 1 − (Σ yi√bi)2. GPA 2261 is the separate standard that governs the gas-chromatograph analysis used to obtain the composition.
The Wobbe Index is the heating value divided by the square root of specific gravity, used to compare the combustion characteristics of different fuel gases.