Numerical investigation of a thermal baffle design for single ground heat exchanger. (25th June 2016)

• Record Type: Journal Article
• Authors: Chen, Shangyuan; Mao, Jinfeng; Hou, Pumin; Li, Chaofeng
• Is Part Of: Applied thermal engineering. Volume 103(2016:Jun.)
• Page Start: 391
• Page End: 398
• Publication Date: 2016-06-25
• Subjects: Thermal baffle -- Ground heat exchanger -- Thermal interference -- Heat flux; Heat engineering -- Periodicals; Heating -- Equipment and supplies -- Periodicals; Periodicals; 621.40205
• DOI: 10.1016/j.applthermaleng.2016.04.106
• Languages: English
• ISSNs: 1359-4311

Abstract

Graphical abstract: Highlights: Add a thermal baffle to the middle of U-tube is proposed to cut the interference between two legs. Three-dimensional GHE models with and without a baffle have been developed. A loss rate is defined to evaluate the thermal interference of vertical U-tube. Baffle is an effective enhancement to the thermal performance of GHE. Variations of borehole wall temperature and heat flux have been studied. Abstract: The thermal baffle is often used to insulate the heat transfer in many energy systems. Hence, in this study, the ideal of inserting a thin baffle in the middle of a U-tube to cut off the thermal interference and improve the heat exchange performance of ground heat exchanger (GHE) is presented, using a finite volume method to simulate the thermal response of GHEs with the same cell number, initial and boundary conditions, two three-dimensional, unsteady models have been developed, the only difference between the models is that for some GHEs, a thermal baffle is installed. By comparing the simulated and experimental results, the traditional GHE model has been validated. A noninterference situation is defined to evaluate the thermal loss rate between the downward and upward legs, then four baffles of different sizes have been installed in the GHEs to investigate the effect of baffle. An economic analysis has been carried out between the two types of GHE, the results show that the baffled GHE can effectively reduce the interference, and it has a considerable benefit in thermal performance and initial investment.