Research on heat transfer optimization of factors influencing shallow ground source heat pump in Beijing area

SUN Qihui; CUI Ying; GAO Xuhui; YE Hongyu; LI Hongxian; Saw Lip Huat; WU Jinshun

doi:10.19956/j.cnki.ncist.2025.05.010

Abstract：In response to the multi factor coupling effect on the heat transfer performance of buried pipes in shallow ground source heat pump systems,this paper focuses on the dual objectives of"influencing factors of buried pipes"and"heat transfer performance".A three-dimensional numerical model was constructed using ANSYS fluid dynamics software to systematically quantify the influence of multiple parameters,including inlet flow velocity,pipe diameter,and thermal conductivity of backfill materials on the heat transfer characteristics of buried pipes.Utilizing the Taguchi experimental design method,a total of 27 orthogonal experiments were con-ducted with 7 factors and 3 levels.Through signal-to-noise ratio analysis and analysis of variance,significant differences and optimal level combinations of various parameters were identified under different evaluation indi-cators,namely inlet and outlet temperature difference,linear heat transfer,and system coefficient of performance(COP).The research indicates that the inlet flow rate has the most substantial impact on the inlet and outlet temperatures(contributing 32.6％)and system COP(contributing 30.7％),while the pipe diameter is the critical factor determining the unit heat transfer per linear meter(contributing 28.9％).The optimal pa-rameter configuration for three typical operating conditions were obtained through multi-objective optimization:the inlet and outlet temperature difference optimization group(A3B2C1D1E3F3G1),unit heat transfer optimi-zation group(A1B2C3D1E3F3G3),and the system COP optimization group(A1B3C3D3E3F2G2).This ap-proach provides a technical pathway for the multi-objective optimization of the system.