Wykorzystanie ekwiwalentnej stałej czasowej w pomiarach szybkozmiennych temperatur w regeneratorze zintegrowanym z palnikiem gazowym

Przedstawiono wyniki badań modelowania matematycznego dynamiki termoelektrycznych czujników płaszczowych. Omówiono wpływ parametrów konstrukcyjnych termoelementu na pomiar temperatury oraz dogodny model - łatwy do wykorzystania podczas pomiaru szybkozmiennej temperatury czynnika w celu korekty dynamicznego błędu przetwarzania. Zaprezentowano wykorzystanie ekwiwalentnej stałej czasowej przy doborze średnicy czujnika termoelektrycznego do pomiaru szybkozmiennej temperatury.

Temperature is the one of the most important parameters which has to be controlled in industrial processes because of technology. The measurement problem of rapidly changing temperature of hot and cold fluids flowing alternately through the regenerator at short intervals is presented in the paper. The metallurgical, high temperature heating furnace with regenerative burners [1, 2, 4, 5, 6, 7] has been used as an example of the measurement problem appearance (Fig. 1). Periodicity of the system operation (Fig. 2) characterized by the interval shorter than 30 s is quite significant due to the dynamical converting error of sensors. The measurement and mathematical modelling results of dynamics of thermoelectric sensors are presented (Fig. 3). The influence of thermocouple construction parameters on temperature measurement is discussed. A convenient model for correcting the error of dynamic processing is described. This model is easy to use for rapidly changing medium temperature. The method presented for approximation of dynamic properties of thermometric sensors by inertia of the first order with the equivalent time-constant ?E is of great practical importance (Fig. 5). This method provides an easy way to assess the impact of construction and thermophysical parameters of the sensor materials and the heat transfer coefficient, from fluid to a thermocouple, on the thermocouple dynamic prop-erties. The use of the equivalent time-constant during the thermocouple diameter selection for measurement of rapidly changing temperature is presented. When minimizing the error of dynamic sensor processing.