Heat flow-based process fluid temperature estimation system with thermal time response improvement

Abstract

A process fluid temperature estimation system includes a mounting assembly configured to mount the process fluid temperature estimation system to an external surface of a process fluid conduit. A sensor capsule has at least one temperature sensitive element disposed therein and is configured to sense at least a temperature of the external surface of the process fluid conduit. Measurement circuitry is coupled to the sensor capsule and is configured to detect a characteristic of the at least one temperature sensitive element that varies with temperature and provide sensor capsule temperature information. A controller is coupled to the measurement circuitry and is configured to obtain a temperature measurement of the external surface of the process fluid conduit and to obtain a reference temperature and employ a heat transfer calculation with the reference temperature, the external surface temperature measurement and a known thermal relationship between the external surface temperature sensor in the sensor capsule and the reference temperature to generate an estimated process fluid temperature output. The controller is also configured to improve response time of the process fluid estimation system mathematically. In some examples, the controller is configured to extract the system tau value from the measured data.