| With China's rapid economic development, urbanization process, building energy consumption is rapidly increasing. As a kind of renewable energy technology, ground source heat pump is energy saving and environmental protection. Because of its advantages, ground source heat pump is in an unprecedented rapid development in china. Hybrid ground heat pump system as a methed to solve the hot and cold load imbalance of throughout the year of underground heat exchange system, could reduce the investment, so it is also an important project engineering solutions to promote related projects especially in hot summer and cold winter zoon for the system's advantage is more apparent. Most hybrid ground source heat pump system is large and complex. Whether the design match of cooling tower and the ground heat exchanger or the formulation of a strategy or system control, they are associated with the characteristics of the local climate, geological features, system configuration and other conditions. As the technology application emerge in Chongqing, it need some kinds of hybrid system design matching method and system control strategies to guide the the implementation of the project. In the paper will undertake the following studies:Base of Chongqing climate characteristics and features of various types of construction, the air condition system load features which has influence of ground heat exchanger operation was reserch. Based on the the air condition system load features, intermittent operation under different operating strategies and different operating flow of heat exchangers were studied.To study the reasonable range of flow of ground heat exchanger, according to previous findings, combined with researching of the usual units and components systems of associated projects, the paper has been obtained optimum flow rate range of system applications to meet the heat exchanger in Chongqing.In order to know the operating characteristics of cooling towers in Chongqing, the paper used the classical theory enthalpy balance equation to make a model of cooling tower operation. According to this model, it obtained a method which using the input water temperature of the cooling tower and outdoor air wet bulb temperature to predict the output water temperature of cooling tower, to guide operating strategies.Through this research, the paper summarizes a design guid which based on analysis of hourly load, winter demand was priority in design of underground heat exchange system, and cooling tower set to meet the summer peak load demand in the same time match the annual heat balance of ground heat exchanger system. The flow rate in underground heat exchanger should be in 0.4 ~ 0.5m/s. Underground pipe system should be partition set, and intermittent operation control. The whole system operation control should be base on the air wet bulb temperature and ground heat exchanger inlet and outlet temperature monitoring, to use cooling tower water temperature prediction to contral cooling tower system start and stop running. |
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