What is the heat test principle of a heat pipe?

- Oct 10, 2018-

Heat dissipation of the heat pipe The heat dissipation of the heat sink should be obtained by the following formula: Q=Gp(h1—h2) where: Q——heat dissipation of the heat pipe, W; Gp——the average flow of the heat medium, Kg/ s; h1——the heat medium at the inlet of the heat pipe, J/Kg; h2——the heat medium at the outlet of the heat pipe, J/Kg. Note: The values of h1 and h2 are based on the temperature and pressure of the heat exchanger at the inlet and outlet of the tested heat pipe, which was found in the First Edition of the Heating and Ventilation Design Manual of China Construction Industry Press in 1987.


Measurement of heat medium parameters 3.2.1 When the heat medium is hot water, when the hot water temperature is lower than the boiling temperature of water at atmospheric pressure, the water temperature at the inlet and outlet of the heat pipe should be measured, or one of the water temperature and heat pipe should be measured. The temperature difference of the hot water at the outlet; when the temperature of the hot water is higher than the boiling temperature of the water at atmospheric pressure, the temperature and pressure of the water at the inlet and outlet of the heat pipe should be measured, or the temperature difference between the water temperature and the hot water inlet and outlet of the heat pipe should be measured. 


Pressure difference. 3.2.2 When the heat medium is steam, the pressure and temperature of the steam at the inlet and outlet of the heat pipe should be measured. The steam at the inlet of the heat pipe should have a superheat of 2 to 5 °C. The test should be only the condensation of the heat pipe. The difference between the water, condensate temperature and the saturation temperature at the steam pressure at the inlet of the heat pipe shall not exceed 1 °C. 3.2.3 Heat medium temperature refers to the temperature at the inlet and outlet of the heat pipe. If it is impossible to measure at this location, the distance between the temperature measurement point and the inlet and outlet of the heat pipe shall not exceed 0.3m. The pipe should be kept strictly insulated and the heat dissipation should be subtracted when calculating the heat dissipation. The insulation layer should extend beyond the temperature measurement point by more than 0.3m. 3.2.4 The accuracy of the measurement of the heat medium parameters should meet the following requirements: Flow rate: ±0.5% Temperature: ±0.1°C Pressure (absolute): ±1% differential pressure: ±5% when the pressure difference is greater than 1KPa When the pressure difference is less than 1KPa ±0.05% KPa