Research of thermal gas flow measurement based on single sensor

Abstract

The paper analyses heat transfer principle of thermal gas flow meter, and presents a method of the flow measurement based on single platinum resistance. The sensor works in CTD (Constant Temperature Difference) controlling mode. The measurement circuit and the signal acquisition circuit are designed to control the platinum resistance at two different temperatures. The gas mass flow is obtained from the voltage of the sensor on both terminals of the platinum resistance, which effectively eliminates the effects of the gas temperature and improves measurement accuracy.