Research On Ground Source Heat Pump Combined With Air Source Heat Pump System For Low Energy Residential Building In North Area

With the continuous improvement of human civilization and the rapid development of science and technology, people’s demand on conventional fossil fuels has increased dramatically, however, not only the excessive exploitation of mineral resources causes the energy exhausted, but also a cumulative increase of energy consumption will lead to environmental pollution issues. Therefore, the rational utilization of energy resources has become a worldwide topic. Energy and environmental issues have been restricting the development of China’s economy, development and utilization of clean renewable energy has become an important goal of China’s development. Solar energy, air, soil etc. is the renewable energy which is abundant and no pollution, and the effective development and utilization of them have a great significance.This paper takes a small residential building in Hohhot as an example, and designs the ground source heat pump system for it. Through simulation we get that accumulated heat load of the building is 9171.94 k W ? h, total 33.02 GJ, accumulated cooling load is 2580.94 k W ? h, total 9.29 GJ, which will cause the absorbed heat is greater than the released heat in pile heat exchangers side of the ground source heat pump, and the efficiency of this system will be gradually reduced in long time running. Therefore, to solve this problem, proposed a set of simulation system design of ground source heat pump combined with air source heat pump, using the air source heat pump as an auxiliary heat source to eliminate the difference between absorbed heat and heat released in the pile heat exchangers side, in order to improve the ground source heat pump systems use efficiency and running time.Through the simulation and experiment research, obtained the following conclusions:First, while the ground source heat pump isolated operation, the difference between the heat absorption and heat release is 14.72 GJ;Second, according to the simulation results, it is concluded that the lowest temperature of the air source heat pump can running is-12 ℃;Third, according to the experimental test results, we can confirmed that the ground source heat pump running is stability, and calculates the building required actually heat load, which was compared with the simulation results, we can get that the error rate between simulation and experimental results is less than 10%.Fourth, analog design a system of ground source heat pump combined with air source heat pump, draw a flow chart of the system, through simulation and calculation can obtained the best combination of temperature, the temperature is-12℃, and the COP of the system is 3.48.The full text through simulation and experiments obtained the above conclusion. These conclusion provides a theoretical basis for the future establishment an actual ground source heat pump combined with air source heat pump system.