CFD Simulation Studies for Vertical Temperature Profile, Pitch Optimisation and Parametric Study of Borehole Heat Exchanger
International Journal of Economy, Energy and Environment
Volume 1, Issue 2, October 2016, Pages: 16-23
Received: Jul. 23, 2016; Accepted: Aug. 10, 2016; Published: Sep. 6, 2016
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Authors
Shiv Lal, Department of Mechanical Engineering, Rajasthan Technical University Kota, India
Subhash Chand Kaushik, Central for Energy Studies, Indian Institute of Technology, Delhi, India
Pradeep Kumar Bhargava, Central Building Research Institute, Roorkee, India
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Abstract
In this communication, simulation studies of a borehole heat exchanger are worked out through computational fluid dynamics (CFD) software. A two dimensional (k-ε) realizable turbulent model with standard wall function is used to evaluate the temperature variation along with depth of BHE, pitch optimization and to determine the effect of two dimensionless parameters as ratio of pitch to borehole diameter and ratio of borehole to pipe diameter. The predicted results are validated through experimental data; and statistical assessment shows a good agreement between simulated and experimental results. The tube air temperature is proportional to depth in cooling mode and BHE can decrease the temperature of air by 13-14°C when ambient temperature observed by 41°C. The optimised pitch for 8 inch borehole and 2 inch diameter U-tube is found to be 4 inch, however two U-tubes are recommended for enhanced performance. The effective borehole to tube diameter ratio is estimated by 4. The BHE system can be used for heating and cooling of buildings it is a feasible solution for sustainable development.
Keywords
Borehole Heat Exchanger, Computational Fluid Dynamics, Optimization
To cite this article
Shiv Lal, Subhash Chand Kaushik, Pradeep Kumar Bhargava, CFD Simulation Studies for Vertical Temperature Profile, Pitch Optimisation and Parametric Study of Borehole Heat Exchanger, International Journal of Economy, Energy and Environment. Vol. 1, No. 2, 2016, pp. 16-23. doi: 10.11648/j.ijeee.20160102.11
Copyright
Copyright © 2016 Authors retain the copyright of this article.
This article is an open access article distributed under the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0/) which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
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