Heat Transfer Study Of Heat Pipe For Radiation Heating Of Walls

Low-temperature heating-supply is widely used in the heating of civil buildings in winter.It has two obvious advantages over the general heating method:one can use low-grade heat sources,and the other is high energy efficiency.If the temperature of the heat source is lowered,it is inevitable to have a higher heat exchange efficiency at the heating terminal devices.This paper proposes the application of efficient heat transfer elements-gravity type pipe radiator in the central heating system of civil buildings to enhance heat transfer,to save energy and achieve a comfortable and satisfactory indoor heating effect.In this paper,a comprehensive study of 1 Low-temperature heating-supply wall radiant and high-efficiency heat dissipation component heat pipe is carried out,and the device is optimized by combining heat pipe and new high thermal conductivity material graphene,which greatly increases the wall heat dissipation area and achieves a better heating.effect.Before the experiment,the selection and design of the heat pipe need to be carried out,mainly to select the heat pipe material and working medium,so that it can meet the needs of this experiment.Build a heating system test bench to conduct a natural cooling experiment of the heat pipe condensing section.Further experiments were made by making room models,using the proposed heat pipe device to heat a wall model made of 50×50 cm2 concrete blocks.Laying two and three heat pipes in the wall,and measuring the temperature in the room model and the wall surface temperature.On the basis of this experiment,an enhanced heat transfer experiment was carried out.The heat transfer effect was compared by changing the parameters between the heat pipe and the heat source temperature,and the new thermal conductivity material graphene was added for the experiment.After the temperature in the room and the wall surface reached a stable state,the average temperature of the wall surface of each group of experiments,the average temperature in the room model,and the temperature variance of each measurement point were compared.The heat pipe is used to heat the wall and numerical simulation is carried out to study the distribution of the indoor increase of 9.9? to meet the indoor temperature requirements;The tube spacing was 15cm and the heat source temperature was 50? is better.The heating method combined with heat pipe and graphene is adopted,the surface temperature of the wall reaches 37.74?,and the temperature in the room reaches 23.41?.Analysis of the data shows that(1)the average surface temperature of the wall is 0.7? higher than that of the individual heat pipe heating,an increase of about 2%(2)the average temperature of the room is higher than 0.4?,and an increase of about 1.7%.The simulation results show that,except for the window area,the indoor temperature field distribution is very uniform,and the PMV index also meets the human comfort range.