A New Analytical Model for the Underground Temperature Profile under the Intermittent Operation for Ground-coupled Heat Pump Systems. (August 2015)

• Record Type: Journal Article
• Authors: Linfeng, Zhang; Quan, Zhang; Min, Li; Yaxing, Du
• Is Part Of: Energy procedia. Volume 75(2015)
• Page Start: 840
• Page End: 846
• Publication Date: 2015-08
• Subjects: Ground-Coupled Heat Pump -- Intermittent Operation -- underground temperature profiles -- short-time response model; Power resources -- Congresses; Power resources -- Periodicals; Power resources; Conference proceedings; Periodicals; 333.7905
• DOI: 10.1016/j.egypro.2015.07.170
• Languages: English
• ISSNs: 1876-6102

Abstract

Abstract: Ground-Coupled Heat Pump (GCHP) systems used in commercial buildings are conventionally controlled by some time schedule strategies. So, a reliable method of modeling underground temperature profiles is of great importance for the operation of GCHP systems. Underground temperature profiles are usually predicted by commercial numerical software. This approach is time consuming and lack the flexibility of modeling various cases of GCHP systems. In this paper, a new analytical model based on a composite-medium line-source model is proposed. The new analytical model agrees well with in situ experimental data. An exhaustive simulation is conducted to explore influencing factors on the ground temperature profile, such as operating time, on-off ratio, heat fluxes and thermal conductivity of back-filled grout. These results indicate that a proper operating schedule and heat fluxes are helpful for maintaining the balance of ground temperature, which may offer an opportunity to develop a control strategy based on the heat flux prediction with the help of GCHP system intermittent operation.