Performance Analysis of Modified Solar Water Heating System for Climatic Condition of Allahabad, India

Authors: Kirti Tewari, Rahul Dev

Abstract:

Solar water heating is a thermodynamic process of heating water using sunlight with the help of solar water heater. Thus, solar water heater is a device used to harness solar energy. In this paper, a modified solar water heating system (MSWHS) has been proposed over flat plate collector (FPC) and Evacuated tube collector (ETC). The modifications include selection of materials other than glass, and glass wool which are conventionally used for fabricating FPC and ETC. Some modifications in design have also been proposed. Its collector is made of double layer of semi-cylindrical acrylic tubes and fibre reinforced plastic (FRP) insulation base. Water tank is made of double layer of acrylic sheet except base and north wall. FRP is used in base and north wall of the water tank. A concept of equivalent thickness has been utilised for calculating the dimensions of collector plate, acrylic tube and tank. A thermal model for the proposed design of MSWHS is developed and simulation is carried out on MATLAB for the capacity of 200L MSWHS having collector area of 1.6 m2, length of acrylic tubes of 2m at an inclination angle 25° which is taken nearly equal to the latitude of the given location. Latitude of Allahabad is 24.45° N. The results show that the maximum temperature of water in tank and tube has been found to be 71.2°C and 73.3°C at 17:00hr and 16:00hr respectively in March for the climatic data of Allahabad. Theoretical performance analysis has been carried out by varying number of tubes of collector, the tank capacity and climatic data for given months of winter and summer.

Keywords: Acrylic, Fibre reinforced plastic, Solar water Heating, Thermal model, Conventional water heaters.

Digital Object Identifier (DOI): doi.org/10.5281/zenodo.1338822

References:

[1] H.D. Ammari, Y.L. Nimir, “Experimental and theoretical evaluation of the performance of a tar solar water heater”, Department of Mechanical Engineering, Faculty of Engineering, Mu’tah University, Karak, Jordan, Energy Conversion and Management, vol. 44, pp. 3037–3055, Feb. 2003.
[2] L.J. Shah, S. Furbo, “Vertical evacuated tubular-collectors utilizing solar radiation from all directions”, Applied Energy vol. 78, pp. 371-395, 2004.
[3] Indira Budihardjo, Graham L. Morrison, Masud Behnia, “Natural circulation flow through water-in-glass evacuated tube solar collectors”, School of mechanical Engineering, University of New South Wales, NSW 2032, Austrailia, vol. 81, pp. 1460-1472, April 2007.
[4] E. Zambolin, D. Del Col, “Experimental analysis of thermal performance of flat plate and evacuated tube solar collectors in stationary standard and daily conditions”, Dipartimento di Fisica Tecnica, Universita` degli Studi di Padova, Via Venezia 1, 35131 Padova, Italy, Solar Energy vol. 84, pp.1382–1396, June 2010.
[5] Ziqian Chen, a Simon Furbo, Bengt Perers, Jianhua Fan, Elsa Andersen, “Efficiencies of flat plate solar collectors at different flow rates”, Department of Civil Engineering, Technical University of Denmark, Kgs. Lyngby, Denmark, Energy Procedia, vol. 30, pp. 65 – 72. 2102.
[6] D.E. Roberts, A. Forbes, “An analytical expression for the instantaneous efficiency of a flat plate solar water heater and the influence of absorber plate absorptance and emittance,”,Council for Scientific and Industrial Research, National Laser Centre, Building 46, P.O. Box 395, Pretoria 0001, Gauteng, South Africa, School of Physics, University of KwaZulu-Natal, Private Bag X54001, Durban 4000, South Africa, Solar Energy, vol. 86, pp. 1416–1427, March 2012.
[7] Rahul Dev, G. N Tiwari, “Annual performance of evacuated tubular collector integrated solar still”, Centre for Energy Studies, IIT Delhi, Haus Khas, New Delhi110016, India, vol 41, pp. 204-223, February 2012.
[8] Y. Taheri, Behrooz M. Ziapour, K. Alimardani, “Study of an efficient compact solar water heater”, Department of Mechanical Engineering University of Mohaghegh Ardabili, Ardabil,Iran, Energy Conversion and Management, vol. 70, pp.187–193, April 2013.
[9] Ka-Kui Tse, Tin-Tai Chow, “Dynamic model and experimental validation of and indirect thermosyphon solar water heater coupled with a parallel circular tube rings type heat exchange coil”, Building Energy and Environmental Technology Research Unit, Division of Building Science and Technology, City University of Hong Kong, Kowloon, Hong Kong, China, Solar Energy, vol.114, pp.114–133, Feb. 2015.