Indirect Method for Measuring the Mass Flow Rate of Composition-changing Gases

The indirect method to measure the mass flow rate of gas with composition change is well known. The method of temperature, pressure and compressibility compensation can be used to measure the mass flow rate of gas, but this is limited to the general gas whose composition is stable or has only a small change. At this time, the composition The influence on the density of the fluid is negligible, therefore the influence on the measured indication is also negligible. For gases whose composition changes greatly, the effect of composition on fluid density cannot be ignored. For example, in refineries and petrochemical plants, the composition of petroleum gas in some petroleum processing processes varies greatly, and the standard state density of fluids varies within a large range. Some combustible gas systems can vary up to 0, 1554〜2』3211^^113〔27〕, at this time, if the standard state density of the fluid is still treated as a constant, the maximum measurement error will reach tens of percent, which is not allowed.