According to the principle of not change the total amount of daily heat exchange, simplify the actual heat release or heat extraction to a rectangular heat transfer pulse for unit length heat exchange borehole, the amplitude of the pulse is the design heat transfer capacity and the duration is the equivalent full load （i.e. design heat transfer capacity） working hours of unit length heat exchange borehole in a day. Based on the linear heat source theory and the superposition principle, several formulas for calculating the average temperature of heat-transfer fluid in ground heat exchanger are deduced on above simplifications, and one of the formulas is verified by long-term field thermal respose tests, which provide theoretical basis for the design of ground borehole heat exchanger, and also provides an effective method to decide heat transfer capacity for unit length borehole heat exchanger based on the conventional thermal response test.
Key words
ground source heat pumps /
groud heat exchanger /
heat load /
intermittent operation /
equivalent full load working hours /
superposition principle
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References
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