Numerical Simulation Of Coupling Heat Transfer Between/in The Human Body And The Spacesuit For Extravehicular Activity

The main purpose of this thesis is to establish a three-dimensional model of heat and mass transfer of human body and the spacesuit cooling ventilation system,which will set foundation for investigating the performance of the spacesuit for extra-vehicular activity(EVA).The CATIA software was used to establish the overall calculation model,the ICEM to draw the meshes,and the Fluent to conduct the numerical simulation under the specific conditions.On the conditions of the metabolic rate of 300 W,the ventilation air flow rate of 150L/min and coolant flow of 100kg/h,the variations of heat transfer rate,and temperatures of human skin,ventilation gas,cooling liquid were computed and analyzed by changing the parameters of liquid-cooled ventilation garments(LCVG).In the liquid cooling and ventilation system of the extravehicular spacesuit,ventilation gas plays an important role in absorbing the metabolic heat of human body.A large amount of body heat is transferred to ventilation air first,then to the liquid coolant.Although the cooling fluid is the main media to take the heat away,the ventilation air is an important bridge.The heat flux across the spacesuit shell has a great influence on the performance of the liquid cooling and ventilation system,which is more sensitive to heat leakage.The influence of moisture content can not be ignored,for that without taking into account the humidity,the calculation result will be somewhat higher.To improve the effectiveness of LCVG,appropriate increases in cooling pipe diameter and thermal conductivity should be adopted.The effect of contact area of coolant pipes and human body on the LCVG is obviously different in different segments.The thermal conductivity of basic clothing markedly affects human body temperature,which can be regulated in a small range.The results can be a reference in the development of EVA spacesuit and its life support system.