gas flow

The temperature of gas flows is an important parameter during the research of heat and mass transfer processes, in the field of gas dynamics, as well as in manufacturing. Therefore, it is necessary to ensure a high level of requirements for the accuracy and reliability of the primary means of temperature measurement. The basic requirements are the simplicity of the design of the thermotransducer, its low thermal inertia, small dimensions, and high reliability during operation in aggressive environments at high temperature and pressure conditions.

The error of measuring the temperature of gas flows by contact methods consists of two main components: 1) the error that occurs in the process of measuring the physical quantity into which the temperature is converted (the error of the measuring means); 2) errors arising in the process of converting the temperature into a measured physical value using a thermo transducer.

Gas flow temperature is an important parameter of the process, determines the quantitative and qualitative indicators of the original product, the presence of defects, the state of technological equipment, as well as the safety of the process. Therefore, its measurement must be carried out continuously, with high accuracy, low inertia and high reliability, since the information signal about the value of temperature is used in information-measuring systems and automatic control and regulation systems.

This paper deals with the accuracy of gas flow temperature measurement in natural gas metering systems. The effect of heat exchange between thermometer well and the pipe wall on the accuracy of gas flow temperature measurement is investigated. A mathematical model is proposed to calculate the additional systematic error of gas flow temperature measurement caused by heat exchange between thermometer well and the pipe wall. Calculation results were compared to the corresponding experimental values of this error.