Heat transfer efficiency characteristics of U-tube buried pipe array

Introduces the two conceptions of comprehensive heat efficiency coefficient and heat stack coefficient in order to obtain the optimal arrangement of buried pipe array. Simulates the heat transfer process using the transient three-dimensional heat transfer model of buried pipe array.Studies the influence of pipe group spacing, array size and array type on the comprehensive heat efficiency coefficient and the heat stack coefficient.The results show that increasing pipe spacing can prolong the duration of high-efficiency heat transfer process for buried pipe, smaller array size can effectively achieve heat balance of rock and soil body, and the rectangle or L-typed buried pipe array is more helpful to enhance heat transfer performance compared with the square array.