How to measure the temperature of the outer wall of an electric kettle with an all-stainless steel bimetal thermometer?

The all-stainless steel bimetal thermometer is manufactured by using the principle of bending due to the different expansion coefficients of the two metals after being heated by different metal sheets pressed together. temperature value. Plug the electric kettle filled with water into the power supply for heating, so that the temperature of the outer wall of the electric kettle gradually rises. Find a plastic foam sponge with a thickness of 15-20cm and stick it closely to the outer wall of the electric kettle (this can reduce the temperature loss and be closer to reality. situation), and dig 2 small holes in the plastic foam close to the outer wall of the electric kettle. Insert the measuring end of the all-stainless steel bimetal thermometer into a hole, so that the temperature measuring end of the bimetal thermometer is on the outer wall of the electric kettle; use the standard platinum-rhodium 10-platinum thermocouple (S graduation number) as the standard Attach the temperature measuring end of the standard platinum-rhodium 10-platinum thermocouple to the outer wall of the electric kettle, and fix it well, and place the lead drawn from the other hole of the plastic foam sponge in the ice kettle. It can be approximately considered that the temperature of the outer wall of the electric kettle measured by the all-stainless steel bimetal thermometer is the same as that of the bearing temperature of the coal mill. After the power is turned on, the temperature of the outer wall of the electric kettle increases gradually, and the data is obtained on the bimetal thermometer and the electronic potentiometer respectively.