SET Proceedings

2978-4387

Caravel Press

10.65582/set.2008.241

2008.241

Enhancement of Sub-soil Thermal Conductivity for Geothermal Heat Pump Systems with Rainwater Collection

Mori

Hiromi

Allinson

David

Hall

Matthew

Gan

Guohui

Riffat

Saffa

School of the Built Environment, University of Nottingham, University Park, Nottingham, NG7 2RD, United Kingdom Ecology & Energy Solution Centre, Mitsubishi Chemical Engineering Corporation, Tokyo, Japan

24082008

7 1 978-1-995850-08-5 1734 1741

24 August 2008

2008

A shallow rainwater collection tank is proposed to improve the thermal efficiency and significantly enhance the economic viability of geothermal heat pumps (GTHP). This system aims to use convective heat transfer within underground tanks as well as instant replacement of stored heat in the event of rainfall. Through a sensitivity analysis using Computational Fluid Dynamics (CFD), the temperature distribution and rainwater stream within the tank were successfully visualised. These results highlighted some of the influential design parameters that will improve the efficiency of heat transfer in the underground structure. The experimental study described here proposes practical design strategies for enhancing sub-soil conditions in order to optimise heat transfer properties in the adjacent ground. The results demonstrated the effects of water content, dry density and compaction energy on the thermal conductivity of the soil. In addition, a comparative analysis was undertaken between two measuring methods of thermal conductivity; the heat flow meter (HFM) and the dual-probe heat-pulse (DPHP) method. Economically priced underground structures and construction procedures are suggested.

geothermal energy rainwater collection heat transfer soil properties dual-probe heat-pulse method

24 to 27 August 2008

7th International Conference on Sustainable Energy Technologies

SET2008

Seoul, Korea

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