Study On Heat And Mass Transfer Characteristics Of Integrated Sublimator Driven Coldplate

Explorations and manned space technology,space station astronaut extravehicular security,day detection craft equipment and the goddess of the moon month,high-temperature short-term big heat dissipation heat problem to be settled urgently for special phase change heat radiator-short-term cooling water sublimator is empty days ideal thermal control device,but weightlessness in space and alternating thermal load conditions and reliable work and is widely used in spacecraft thermal control and the extravehicular activity.Integrated sublimation drives cold plate?Integrated Sublimator Driven Coldplate,ISDC?is a new kind of researching water Sublimator proposed recently,also referred to as the ISDC water Sublimator,ISDC water Sublimator is to sublimate drive cold plate?Sublimator Driven Coldplate,SDC?coupled with the loop drive pump,system simple and light weight,heat dissipation,high efficiency and reliable good adaptability,is China's manned space explorations and auxiliary cooling inevitable choice.Ice-water heat mass transfer in porous media is ISDC water sublimator key basic research and development and to conquer difficulties,the paper carried out integrated sublimation driven heat cold plate theory of mass transfer characteristics test and numerical simulation research,revealing the influence law of porous plate structure on the heat transfer fluid mass transfer,to obtain the optimal structure design model,get the heat mass transfer critical status-"breakdown?feed directly into the vacuum?conditions",providing theoretical basis for research and development of new type ISDC water sublimator.Study on theoretical model of heat-mass transfer in water sublimator.The water sublimator involves many complex physical phenomena of heat and mass transfer.Based on the working mechanism of water sublimator,the theoretical models of solid skeleton heat transfer,fluid heat transfer and heat transfer coupling in porous media are established.A flow mathematical model containing the phase transition of working medium in porous media and a permeability mathematical model to characterize the pore size of porous media are established.The mathematical model of mass and energy conservation of water sublimator is established.The discriminant equation of"breakdown"in water sublimator is given.Study on the influence of structure properties on heat and mass transfer of SDC water sublimator.SDC water sublimator is an important part of ISDC water sublimator.In this paper,the effects of the structure physical properties on the heat and mass transfer of SDC water sublimator are studied by numerical simulation.A comparative study on the influence of channel structure shows that the feed water has better uniformity in porous material when the feed channel is parallel with the porous sublimation pipe.Was studied to determine the tank type,aluminum foam and sublimation tube pore size and porosity of the influence law of the SDC water sublimator heat mass transfer,found that with the increase of foam aluminum pore diameter and porosity,water sublimator installation surface temperature is higher and higher,but will have little impact on the feed water inlet pressure,with the increase of sublimation tube pore diameter and porosity,water inlet pressure decreases,but the impact on the mounting plate surface temperature is small;When the porosity of aluminum foam is 0.7,the pore diameter of the sublimation tube is 5-6 m and the porosity is 0.15,the heat transfer effect of the water sublimer is better,and the"breakdown"phenomenon can be effectively avoided when the thickness of the sublimation tube is about 2mm.Study on the influence of boundary characteristics on heat and mass transfer of SDC water sublimator.Under the premise of determining the structure parameters of SDC water sublimator,the influence of boundary characteristics such as heat load,arrangement,working medium state and radiation heat transfer on heat and mass transfer of SDC water sublimator is numerically studied.It is found that the greater the heat source power and the more concentrated the arrangement,the more uneven the surface temperature of the mounting plate,and the greater the possibility of"breakdown".A new sublimation mixing working medium for water supply mixed with ethylene glycol?H₂O-?CH₂OH?₂?is put forward.H2O-?CH2OH?2 mixed sublimation working medium can effectively improve the heat transfer effect of water sublimator theoretically.The inlet water temperature will affect the surface temperature distribution uniformity of the installation plate.The closer the water temperature is to the average surface temperature of the installation plate,the smaller the temperature uniformity will be.In the special mission of space and sky,the heat exchange of solar radiation cannot be neglected.Experimental study and numerical simulation of heat transfer in ISDC water sublimator.The structure parameters of SDC water sublimator are determined.A new ISDC water sublimator is designed by adding a cold plate on the upper and lower surface of SDC water sublimator.The heat transfer test system of ISDC water sublimator device was designed,and the ground test bed was built.The heat transfer law of ISDC water sublimator device was studied for the first time in China,and the possible heat dissipation mechanism of ISDC water sublimator in circulating working medium system was classified and studied.It is found that the water sublifier has a very good heat dissipation effect when it separately dissipates the heat from the electronic components on the mounting plate or the circulation loop.At the same time,when it comes to heat dissipation of electronic components and circulating water,the heat dissipation effect of circulating water is relatively poor,and the heat dissipation effect of electronic components is relatively good.Circulating water at high power at low speed and low temperature can be combined with feed water sublimation to dissipate heat for electronic components.When circulating water flows at high temperature under low power,feed water sublimation is the main way of heat dissipation.Based on test results,the numerical simulation to study the circulating water flow rate,temperature and heat source power of the influence law of heat transfer of water sublimator,and compared with experiment was carried out,and the error between the two is very small,therefore,in the reasonable simplified numerical simulation results can satisfy the water sublimator application in engineering.The theoretical model of porous heat and mass transfer of ISDC water sublimator and the research method and results of the transfer law fill in the blank of domestic related research,and lay a certain foundation for the successful application of ISDC water sublimator in China,which can provide important reference.The first test proves the reliability of numerical simulation of heat transfer characteristics of ISDC water sublimator.