摘要 |
Thermal dispersion probes used as flowrate sensors in process control of a medium heated by a heater. The device includes a reference temperature sensor for producing an electrical signal indicative of the temperature of the medium in which it is immersed, and an active temperature sensor for producing an electrical signal indicative of the temperature of the medium adjacent the heater. The temperature difference between the active sensor and the reference sensor is processed in a processor which varies the heater power to maintain the temperature differential between the active sensor and the reference sensor within a predetermined range, whereby the predetermined range provides an optimal sensitivity for the probes. |