Although the mid-deep ground source heat pump could be more excellent for heating compared to other heat pumps, whose well depth is usually 2000–4000 m underground, the references on it is far fewer than the market demand to apply it more. To facility the application of the mid-deep ground source heat pump and the heating problem solution to transform the coal-boiler used in a Logistics Park of Lanzhou city, firstly, this paper established a three-dimensional numerical model of mid-deep ground source heat exchanger, and analyzed the effects of well flow, diameter and depth on heat pump performance with the help of Fluent software. And then, the heating source renovation to mid-deep ground source heat pump was carried out and the test funded by the local government was followed from February 1, 2018 to March 31, 2018. It is concluded that the numerical analysis is reasonable and the heating system is effective and reliable, whose average COP (coefficient of performance) and cumulative power consumption is 3.47 and 67 727 kWh respectively during the test period.
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