Enhancement of heat transfer for ground source heat pump systems

Mori, Hiromi (2010) Enhancement of heat transfer for ground source heat pump systems. PhD thesis, University of Nottingham.



Uptake of geothermal heat pump (GSHP) systems has been slow in some parts of the world due to the unpredictable operational performance, large installation space requirement and high installation costs. Therefore, design modification was searched in order to improve the feasibility. With regard to relatively small impact of the construction costs, efficient thermal energy collection was targeted in horizontal ground-loop systems with shallow underground construction.

The research started with a sensitivity analysis of the underground heat collection system using computational fluid dynamics (CFD). The results indicated essential design parameters to enhance the performance. Strategies to improve one of the parameters, thermal conductivity of soil surrounding the heat exchanger, were investigated through lab experiments. Subsequently, further design optimisation with the CFD intended to select the most competitive modified design against the existing design.

It was discovered that an indication to achieve economic and practical modifications for efficient heat collection was to increase the moisture content of sub-soil up to the optimum moisture content (OMC). Annual operation analysis with the CFD disclosed that additional costs for even simple design modifications could easily worsen the payback period. Consequently, solutions to improve the performance of the GSHP within reasonable payback period were proposed.

Item Type:Thesis (PhD)
Supervisors:Tucker, R.J.
Omer, S.
Uncontrolled Keywords:ground source heat pump systems, heat transfer, gshp, geothermal heat pump, computational fluid dynamics, optimum moisture content, thermal conductivity
Faculties/Schools:UK Campuses > Faculty of Engineering > Built Environment
ID Code:1483
Deposited By:Ms Hiromi Mori
Deposited On:24 Feb 2011 15:59
Last Modified:24 Feb 2011 15:59

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