Research On Issues Related To Ground Source Heat Pump System Of Some Engineering Project In Yueyang

With the acceleration of urbanization,the new construction area is increasing by 1.8-2.2 billion m2 per year.And it is expected that the new construction area will be about 30 billion m2 by the end of 2020.Such a large-scale new constructions also bring in enormous energy consumption. Construction industry, industry and transportation are listed as the key energy-saving industry. Building energy consumption will exceed other energy consumption and rank first. So building energy-saving is increasingly important.The application of ground source heat pump technology is of great significance to ease the energy consumption of buildings. Although ground source heat pump has been widely applied, there are still some problems that designers should pay attention to in the system design and operation. In this paper, combined air conditioning and sanitary hot water system of Hong Run Home located in Yueyang,the ground source heat pump system design problems are researched:1.Given the great uncertainty of the use of airconditioning,it is necessary to consider the simultaneous coefficient when the load of larger esidential buildingsis calculated.In the calculation of the total length of the buried pipe, due to the results calculated by standard theory are different from the seobtained by soil test,it is necessary for the large ground source heat pump system to do soil thermal property test.Mathematical model is established based on the depth of buried pipes. Only when the depth of buried pipes are more than certain value can the minimum flow rate requirement from standardization be meted, if the unit depth heat transfer and the temperature difference between entering water and leaving water of buried pipe side both keep constant.In addition, in the hot summe r and cold winter area, usually cooling load in summer is far greater than the heat load in winter, so the auxiliary heat of cooling tower is conducted in order to balance cold and heat of soil. For the large load constructions, an effective control strat egy is proposed to run control ground source heat pump and cooling tower in the state of part load and full load.2.In the selection of life hot water system,the mode that combining the solar hot water system and ground source heat pump hot water system is designed.For the joint operation of the life hot water heat pump unit and air conditioning heat pump, the life hot water unit take heat from the soil while the air conditioning unit release heat to the soil in summer. In this paper, two operation strategi es to the summer operation of the composite ground source heat pump system are put forward to, and the reliability of two operation strategies is also analyzed.Thus, the efficiency of the system has been improved under the two operational strategies.3.Layered heat storage water tank commonly used in current solar system are introduced and analyzed. Results show that layered heat storage water tank has the advantages of quick starting, long heating cycle,high efficiency. For the centralized hot water supply system of the building, layered heat storage water tank should be taken consideration into to save energy consumption of hot water.