Research On Ground Source Heat Pump Coupling Ice Storage Air Conditioning System

At present, the problem of energy shortage and environment pollution is becoming more and more serious. In the construction industry, the proportion of energy consumption of the air conditioning system has been greater, so it is necessary to implement energy conservation. The ice thermo storage system use the refrigeration mechanism at and the "Valley" preferential tariffs to reduce the amount of electricity expenditure at night. The ground source heat pump system can use geothermal energy, which taking into account the winter heating and summer cooling. Combined the ground source heat pump and ice thermo storage system, let ground source heat pump works in the winter and the ground source heat pump and ice thermo storage system run at the same time in the summer which can use refrigerant group ice at night and can afford to cut a peak to fill valley during the day.This paper analyzes the characteristics and advantages of the combination of ground source heat pump and ice thermo storage system and evaluates the performance of the system, which is based on the coupling system of a project in Qingdao area.First of all, using dynamic load simulation software to calculate the annual hourly cooling and heating load, and then calculating the monthly cumulative load and annual cumulative load. At the same time, this paper calculates the typical summer design day hourly cooling load, 75% of the typical design on hourly cooling load and 50% of the typical design hourly cooling load. The thermal conductivity, volume specific heat and initial temperature of the soil were determined after soil thermal physical properties experiment. Through the above work, the selection of office building air conditioning system, setting of model establishment process parameter and the length of buried pipe were determined.Then based on the design scheme of this system and the control strategy, the TRNSYS simulation platform of the coupling system is established to analyze the heat pump evaporator and condenser of supply and return water temperature and heat pump COP, underground pipe, heat discharge average temperature. The simulation results are in agreement with the temperature range of the measured data, which indicates that the model is correct and feasible. By comparing the data before and after optimization of the coupling system model, this paper concluded that the auxiliary cooling device can effectively improve the uneven heat transfer of soil, and the performance of heat pump can be improved effectively, and the system can be operated stably for a long year.At last, through the reasonable calculation of the operating expenses of the composite air conditioning system, this paper come to the conclusion that the combination of ground source heat pump and ice thermo storage system is not only environmentally friendly, but also has a relatively low initial investment and low operating cost compared with the conventional ground source heat pump system.