Supercritical Gas Measurement and Control

Fluids like carbon dioxide(CO2) are difficult to measure when they move towards the inter-phase stage between being a liquid and a gas. For example, the supercritical point of CO2 is reached at 73.8 bara and 31.1℃. Beyond these conditions, physical properties like density(ρ) and heat capacity(Cp) change very rapidly as result of pressure or temperature variations. This makes an accurate mass flow measurement, based on the thermal principle, very difficult.

Flow Scheme