Abstract: Aiming at the problem of thermal comfort of astronauts wearing space suits for survival in different conditions during the emergency return process with cabin pressure loss, a human space suit thermal model is established based on Matlab. The human thermal model is established based on the Fiala model, and the space suit thermal model is established by the lumped parameter method. The simulation results of the human space suit thermal model in different working conditions are in agreement with the data in literature, and the correctness of the model is verified. On this basis, the human body thermal comfort under different pressure loss conditions is analyzed based on the DTS thermal comfort algorithm, the relation among human thermal comfort, heat dissipation and ventilation gas humidity is obtained, and the proposals to optimize the system are put forward. The model and its simulation results can provide references for the design of cabin pressure protection system and the establishment of astronauts life support scheme in China.

Key words: Human thermal model, Space suit thermal model, Numerical simulation, Thermal comfort, Cabin pressure loss