Thermocouple response time measuring device and method

Abstract

The invention discloses a thermocouple response time measuring device and method, and the device comprises a constant-temperature and constant-speed water tank, the interior of the constant-temperature and constant-speed water tank is provided with a rotating blade, and the side wall of the constant-temperature and constant-speed water tank is uniformly provided with a plurality of overflow pipes. A tested thermocouple which is driven by the mechanical arm to move up and down is arranged above the constant-temperature and constant-speed water tank; an output signal of the thermocouple to be tested passes through the ice bottle and the signal amplifier and then is input into the data collector; the time constant of the thermocouple to be tested is the time difference when the output temperature of the thermocouple to be tested reaches 10% and 73.4% of the step value respectively. According to the measuring device, the overflow pipe improves the stability of a flow field, and the signal amplifier improves the response speed of a signal processing and collecting part; according to the method for calculating the response time through different step percentage time differences, errors caused by the fact that the initial moment is difficult to measure are avoided, and the accurate and reliable response time measuring device and method are provided for quick response thermocouples such as a connecting shell type thermocouple and an exposed end type thermocouple.

Description

technical field [0001] The invention relates to the technical field of temperature sensor response time measurement, in particular to a thermocouple response time measurement device and method. Background technique [0002] When the contact temperature sensor measures the temperature of the fluid with rapid temperature change, it generally cannot respond to the measured temperature immediately, and it takes a certain time to reach the thermal equilibrium state. Only when the temperature sensor and the measured fluid reach thermal equilibrium, the temperature value of the sensor response is the temperature of the measured fluid. The dynamic response characteristic of the sensor refers to the relationship between the temperature of the temperature sensor and the temperature increment of the measured medium. In practical calibration, the response time is often used to describe the response of a temperature sensor to a step temperature. The response time refers to the time req...

AI Technical Summary

Problems solved by technology

During the actual test process, due to the rotation of the medium in the constant temperature tank, its liquid level is concave in the center and high around, and the optical path cannot be flush with the liquid level, so the initial time obtained is the same as the time when the measured temperature sensor actually contacts the water surface. There is a deviation

[0007] During the response time test of shell-type and exposed-end thermocouples, it is difficult to measure the initial moment accurately, resulting in a large error in the response time measurement, which is a difficult problem encountered in the response time measurement of this type of temperature sensor.

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