| In recent years,along with the rapid development of social economy in China,people have paid more and more attention to energy safety and ecological environment management.Although our country has vast territory and abundant energy supply,the per capital possessiveness is lower than the world level.In terms of the energy consumption structure,the non-renewable energy consumption still accounts for a large proportion.In order to promote the scientific research and development,the Chinese government has formulated many relevant policies on the use of clean and renewable energy.In response to the call of government departments for energy conservation and emission reduction,the heat pump technology represented by ground source heat pump has been rapidly developed.In the research,taking the soil source heat pump system in Huainan area as the research subject,the development status,research status and working principles of the ground source heat pump system are expounded.The several commonly-uesd energy consumption simulation software are summarized and analyzed,pointing out which simulation software will be used in the following research.Combined with the meteorological data,actual building parameters and interior design parameters of Huainan City,the hourly heating and cooling load is calculated by TRNSYS software in intermittent operation.The peak value of cooling losd is 10.4k W,the peak value of heating load is 9.13 k W,and the ratio of summer and winter cooling load is 1.14:1.It is pointed out that the load calculated by intermittent operation is more accurate.The simulation model of ground source heat pump is established in Studio by using mathematical model and theoretical knowledge.The system is simulated by inputting detailed parameters.In order to verify the feasibility of the model,the changing trend of the inlet and outlet temperature of ground source side and user side during winter and summer operation is compared.Based on the effective operation time of the heat pump unit of 30 years,the average soil temperature,the buried pipe outlet temperature and COP of the heat pump unit when the system is running in a single or double season are analyzed.The results show that when the system is only running in a single season,whether the cooling in summer releases heat to the soil or the heating in winter absorbs heat from the soil,the soil thermal imbalance will occur over a long period of time.When the system is running in both winter and summer,although the soil temperature has risen,it is closer to the initial temperature.Moreover,in the actual system unit,domestic hot water at 45℃ can be provided to the user.It can release the excess heat in the soil,which is beneficial to the operation of the system.Under the cooling condition in summer,the outlet temperature of the buried pipe is basically kept around 22.5℃,and the COP value of the unit is 4～5.3.Under the heating condition in winter,the outlet temperature of the buried pipe is basically kept around 12.5℃,and the COP value of the unit is 3～4.53.The influence of four factors on the heat transfer characteristics of the buried pipe is introduced.The results show that the spacing and depth of drilling holes and the thermal conductivity of soil and backfill materials have certain influence on the heat transfer of the buried pipe.The orthogonal test is applied to carry out multi-level orthogonal test for four factors.The range analysis results show that the order of influence of all factors on the average temperature of soil is as follows: thermal conductivity of soil > depth of drilling holes >spacing of drilling holes > thermal conductivity of backfill materials.The order of influence on the outlet temperature of the buried pipe is as follows: thermal conductivity of soil > depth of drilling holes > thermal conductivity of backfill materials > spacing of drilling holes.Figure [64] Table [12] Reference [83]... |
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