Study On The Influential Factors Of Personalized Air Supply In Low Pressure Environment Based On Warm Manikin

Personalized air supply is to deal with the air directly to the body breathing area,improve the air quality of the work area,air conditioning,low energy consumption.At the same time,it also fully consider the individual differences in environmental demand,regulation and more flexible,is widely used in buildings and vehicles in the air-conditioning system.As the individual air supply for the local air supply,the body’s thermal sensation,the human body and the surrounding heat transfer characteristics are also different from the traditional air supply.In addition,China’s topography and terrain changes,there are many highland areas.People in the plateau region in the work,life,tourism will be in a low pressure environment;In addition,the aircraft cabin generally maintain 0.8atm(about 2300 m altitude)pressure environment.Therefore,in our lives,low pressure is no stranger.In low-pressure environments,changes in air density result in heat transfer characteristics that are not used in atmospheric environments.Therefore,in this paper,the heat transfer characteristics and influencing factors of individual air supply under low pressure are studied theoretically and experimentally.In the low pressure environment simulation cabin of HVST Lab of Qingdao University of Science and Technology,the experiment was carried out by the warm-up manikin.The contents and achievements of this paper are as follows:The theoretical study on the heat dissipation characteristics of human body under low pressureThe main difference between the thermal equilibrium of the low-pressure environment and the thermal equilibrium under normal pressure is the change in the air density caused by the atmospheric pressure.Atmospheric pressure decreases,the convective heat transfer coefficient is also reduced,resulting in convective heat transfer reduction;and radiation heat transfer coefficient and radiation heat transfer basic with atmospheric pressure unchanged.In the low-pressure environment,the air flow will cause the body convection heat change.2.Experimental study on heat dissipation characteristics of individual air supply in low pressure environmentThe skin temperature,heat transfer coefficient and heat transfer of the human body under low air pressure were explored and the change trend of the skin temperature under the low metabolism level was explored.The heat transfer coefficient Vertical distribution of the law.Linear regression was used to describe the trend of skin temperature with atmospheric pressure.The experimental data are used to describe the experiment.The correction formula of the convective heat transfer coefficient is given,and the trend of the ratio of the convective heat transfer to the radiant heat transfer in the process of pressure reduction is analyzed.The study of influencing factors of personalized air supply in low pressure environmentThe effects of atmospheric pressure,ambient temperature,local blowing speed and air blowing position on the individual air supply were studied by using the orthogonal experimental design.The skin temperature,convective heat transfer coefficient,heat transfer coefficient,Radiation heat transfer coefficient,convective heat transfer and radiation heat transfer ratio.The variance analysis is used to describe the effect of different factors on the experimental indexes,and the effect of different factors on the experimental indexes is described by means of the range analysis with different factors and different levels.Finally,the influence rule and significance of the selected factors on the experimental indexes were obtained.