Performance research of portable thermoelectric cooling garment under different working conditions

Liquid cooling garment (LCG) is a thermal protection measure to relieve heat stress and improve human thermal comfort in a high-temperature environment. This study designs a liquid cooling garment based on thermoelectric cooling technology aiming at the disadvantages of traditional cooling garments such as heavy and poor effectiveness. The effects of ambient temperature and exercise intensity on the cooling effect of the liquid cooling garment are studied by a series of human body tests in a simulated high-temperature environment, so as to determine the optimal water inlet temperature of the liquid cooling garment. The experimental results show that there exists a “critical value” of water inlet temperature which can satisfy both thermal comfort and energy saving. Under the condition that the ambient temperature is 40 °C and the exercise intensity is walking, the “critical value” of the water inlet temperature of the cooling garment is about 22–24 °C, and the average cooling temperature difference is about 3.2–5.1 °C. The “critical value” of the water inlet temperature is all 22–24 °C under the condition that the exercise intensity is walking, and the ambient temperature is 38 °C, 40 °C, and 42 °C. The “critical value” of the water inlet temperature of the liquid cooling garment is 26–28   °C, 22–24   °C, 20–22   °C under the condition that the ambient temperature is 40 °C and the exercise intensity is sitting, walking, and jogging. The stronger the exercise intensity, the lower the “critical value” of the water inlet temperature to achieve the same cooling effect. The results show that ambient temperature has less effect on the “critical value” than exercise intensity. The research results of this paper can provide the direction and basis for selecting the cooling performance of thermoelectric LCG in different conditions and guide the performance testing of liquid cooling garments in the future.