Study On Solar Combined Heating System Applied In Plateau Airport Buildings

The winter of plateau area is cold and long,its solar radiation intensity is large,its sunshine time is long and its heat load of airport building has significant fluctuation changes.Besides,its special climatic conditions and the special changes of heat load,lead the difference between the heating energy resources configuration of heating system in plateau area and In plain area.At present,heat supply sources of building in plateau area are mostly conventional boilers,air-cooled heat pumps,etc.Increasing the capacity of heating equipment,which is commonly used to meat heating requirements,raises the heating energy consumption of high-altitude cold areas.It is a waste of energy.The high-altitude heating system is running inefficiently and poor applicability.This paper aims to know well and make full use of the rich solar energy resources in plateau area to meet the significantly fluctuating heat load demand of the airport building heating,and improve the energy efficiency of heating system operation.Firstly,the climatic characteristics of plateau area and the load characteristics of airport building are studied.According to the characteristics of local climate and load,solar-water source heat pump compound heating system is used to meet the heating requirements.Secondly,the coupling model of solar-water source heat pump compound heating system of airport building in plateau area is established.And the mathematical models of solar collectors,water source heat pumps,stratified heat storage tanks and model of air conditioning equipment-water pump are established respectively.A software is developed to simulate and evaluate the solar-water source heat pump of airport building in plateau area compound heating system.The software can make the dynamic numerical simulation of the operation of the solar-water source heat pump compound heating system.Then compare it with conventional water source heat pump system and gas system and gives evaluation of the energy efficiency,economy and environmental protection of these heating systems.Thirdly,the reliability and correctness of the software mathematical model are verified by comparing the measured data and software simulation data of the heating system of airport building in plateau area.Then the operation characteristics of the composite heating system are analyzed by this software.According to the conclusion of software analysis,the main factorsinfluencing the volume of the collector,the inclination angle and the area of the solar collector and the heating temperature of the system are optimized.Finally,the idea of using phase change heat storage water tank instead of a conventional heat storage tank is proposed.When the storage capacity is constant,the occupied area and heat dissipating capacity of traditional storage tanks is larger than the ones of phase change heat storage water tank.So a mathematical model of phase change heat storage tank is established.Without real operation of phase change heat storage tank of airport building,which is used in solar-water source heat pump compound heating system in highland cold airfield,the test bed of phase change heat storage tank is used for experimental study,and for measuring,contrasting and verifying the box module of phase change heat storage tank.After several tests,the parameters of heat transfer efficiency and heat storage intensity were obtained,and the mathematical model was verified.At the same time,the influence factors and the change rule of phase change heat storage tank are simulated,optimized and analyzed.The different characteristics of the inorganic phase change material and the organic phase change material are also analyzed in the tests.