| At present,with the development of human society and the continuous growth of population,the primary energy on the earth is increasingly exhausted,and energy has become an important issue in the economic development and people lives of all countries.And the burning of fossil fuels makes the natural environment increasingly worse,energy conservation and emission reduction are imminent.In China total energy consumption,building energy consumption accounted for 27.45%,and heating and air conditioning energy consumption accounted for more than 60%of the total building energy consumption,so the building used of renewable energy will have great development potential in the future.Among them,solar energy is the cleanest and richest energy that can be utilized.By studying on the predecessors'conception and design,analysing the components of solar heat pipe wall,and finally microchannel heat pipe was selected as heat transfer element array,then heat pipes that were bended were installated in the south wall,the microchannel heat pipe solar energy wall that can weaken the thermal retardation of wall was proposed.Through the experimental study,it can be see that the heat transfer of heat pipe wall changed obviously with the solar radiation,and the indoor temperature was always higher than the outdoor temperature in daytime during the heating season,and the temperature difference is 1.4~13.1?.The maximum effective heat gain of the heat pipe wall is 287 kJ/m~2,and the maximum instantaneous heat efficiency is 81.6%.Then through comparative experiments,it can be see that the DH(heating day hours)of the daytime in the heating season is decreased by 5.7?·h and that of nighttime is 3.3?·h,the average superheat in summer is decreased by0.66?a nd the coefficient of superheat time is decreased by 0.12.Thus,it is clear that the heat pipe wall can well meet the purpose of heating in winter and resisting heat in summer.In this study,the coupling of unsteady heat conduction of walls,radiation and convection heat transfer between enclosures caused by solar radiation was considered.The mathematical model of heating system of microchannel heat pipe wall in winter was established by using dynamic network analysis method.The thermal calculation temperature of the experimental room and microchannel heat pipe wall was calculated by Matlab programming,and then compared with the experimental data.It was proved that the mathematical model was correct.The mathematical model and computer program were used to optimize the number of heat pipes per unit collector wall area and the area of microchannel heat pipe.It was found that the most suitable heat pipe collector area per unit area in heating season was 0.36m~2,and increasing the area of microchannel heat pipe collector wall can increase indoor temperature.SLR(the sun's heat load ratio)method is used to evaluate the energy saving and economy of the application of microchannel heat pipe solar wall in Beijing farmhouse.Then the auxiliary heat supply,energy saving rate and the recovery period of the room cost were calculated,and I predicte the average indoor temperature in heating season,which provided the solar thermal engineering calculation for new rural residential buildings.Finally,it is indicate that the design of microchannel heat pipe type solar energy collection hot wall used in rural residence is feasible. |
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