Methodology for Determining the Response Time of Thermo Transducers for Measuring the Temperature of Gas Flows

2019;
: pp. 89 – 93
https://doi.org/10.23939/jeecs2019.02.089
Received: October 18, 2019
Revised: November 21, 2019
Accepted: December 05, 2019
Authors:
1
Lviv Polytechnic National University

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. When measuring a time-varying gas flow temperature, the thermo transducer does not have time to keep track of the temperature change since it takes some time to change the temperature of its sensitive element. Distortion of thermo transducer due to the non-stationarity of thermal processes both in the thermo transducer itself and between it and the environment is due to its inertial properties (thermal reaction). Due to these properties, there is an additional difference between the temperature of the sensing element and the temperature of the gas flow, which determines the dynamic error in measuring the flow temperature.  The method of determination of inertial properties of thermo transducer for different gas flow velocities by the measured value at one basic flow velocity is proposed in the article.

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V. Fedynets. Methodology for determining the response time of thermo transducers for measuring the temperature of gas flows. Energy Engineering and Control Systems, 2019, Vol. 5, No. 2, pp. 89 – 93. https://doi.org/10.23939/jeecs2019.02.089