Heat Transfer Characteristics Of The Wall Built-In Separate Type Heat Pipe

Research on heat pipe used in the building heating field.is still in the initial stage. This paper is based on making full use of renewable energy (solar energy resources),adopted passive design concept, combined with the heat pipe technology, present a solar-built in separate type heat pipe wall heating system. Currently, research on the heat transfer characteristics of the wall installed heat pipe is little, the largest proportion is still researched on the heat transfer character-istics of the heat pipe itself. The main work of this paper in order to determine the structure of the heat pipe heating wall.Analysis of the influence of wall structure form and structure installed on the heat transfer characteristics of heat pipe.Present technical measures to enhance heat transfer capability between heat pipe and the wall.Based on the research of floor radiant heat transfer, In order to study the floor radiation heat transfer is the basis of this research, established the wall heating system mathematical model. According to the purpose of this reaearch, make suitable assumptions on heat transfer process of the wall heating system, established two dimensional heat transfer model of the wall heating system, in case of the system is in continuous operation condition, without considering the heat source intermittent operation (discontinuity of solar energy resources), the heat transfer process for steady state process. Used numerical calculation of heat transfer process of the separated type heat pipe wall built in the simulation software. In this paper, the quantity of heat pipe,effect of fin length, fin thickness, layer of material factors on the heat transfer power of the heat pipe wall, at the same time analysis the surface temperature distribution and heat flux density.Solar energy-built-in separate type heat pipe heating wall system, has the characteristics of work with non-power, and realized the zero energy consumption of the heating process. The number of heat pipe has a little influent on its heat flux density. When the filling and leveling material is cement mortar and not installed the fin on heat pipe, when the number of heat pipe is 4, the surface heat flux is 432.3W/m2; when increased to 12,the heat flux is up to 398.8W/m2, just increased by 7.7%. Installed the fin on heat pipe can significantly enhance the heat transfer power. When filling and leveling material is cement mortar, the numberof heat pipe is 8, the length of fin installed on heat pipe the fin is OL,1/4L,1/2L,3/4L,1L, the heat flux maximum increased of 211.4%. While the choice of structural material had a great influence on the heat transfer power. Structure layer respectively, the use of lime sand brick, aerated concrete block, wall surface heat flux density respectively for 615.3W/m2、276.3W/m2. The use of lime sand brick heat pipe surface heat flux compared to the concrete block is increased by 122.7%. The use of aerated concrete block and brick, the heat transfer power is more than doubled. When selected the structural layer materials, we should consider all the factors comprehensively, and select the appropriate material.