Heat Transfer Analysis And Application Of Porous Phase Change Heat Storage Wall

With the rapid development of society,people's demand for living environment is no longer a simple space structure,but develop in the direction of healthy,comfort,energy conservation and environmental protection.As a kind of energy conservation and environment protection material,phase change materials are widely used in building envelope.Through the way of heat storage in the daytime and heat release at night,phase change materials can attenuate difference of outdoor temperature and increase the delay time of peak and valley temperature,so as to achieve the purpose of building attemperation and energy conservation.In this thesis,COMSOL software is used to simulate the heat transfer performance of porous phase change regenerative wall under constant room temperature.The difference between the wall temperature fluctuation and the peak valley temperature delay time was taken as the evaluation index,the influence of the parameters of porous phase change materials on heat transfer characteristics of wall was analyzed.The results showed that the effect of comprehensive temperature adjustment was better when the porous phase change heat storage plasterboard was placed on the inner surface of the wall,the phase-transition temperature was 24 ? and the phase change interval was 3?.The greater the value of phase change latent heat and the porosity of phase change plasterboard in the 4 values studied,the better the effect of comprehensive temperature adjustment.Secondly,under the condition of unsteady room temperature,the influence of wall thermal charge and discarge on the indoor thermal environment is analyzed by the unsteady heat transfer model of a passive solar energy room with a porous phase change storage wall.Reference to a room without porous phase change materials,through numerical simulation,the temperature changes of the room with porous phase change heat storage wall was relatively gentle,the fluctuation range of indoor air temperature and the heat flow of inner surface of south wall was relatively small,peak and valley temperature delayed more,the heat storage capacity was high and the superheating load of the room was reduced by 50.1%.Finally,the optimum design of porous phase change heat storage wallboard was studied,a theoretical calculation method of heat storage of phase change materials has been obtained through the analysis of the room thermal comfort temperature.Continuous optimization analysis was made on the actual temperature adjustment effect of phase change materials by taking thermal discomfort intensity and utilization ratio of phase change materials as evaluation indexes.The room with porous phase change storage wall in the third chapter was used as research model to study the thickness and layout position of the porous phase change heat storage wallboard.The results showed that when the content of phase change materials was 9.701 kg,the thickness of the phase change wallboard was 6mm,the utilization ratio of phase change materials was the highest,the effect of temperature regulating was better.When the phase change wallboard was placed on the south wall,the content of phase change materials required was the least.The research conclusions provide theoretical support for the optimal design of porous phase change heat storage wallboard,and have an important guiding role.