Document Type : Research Article

Authors

1 Department of Mechanical Engineering, Payame Noor University, Iran

2 Payame Noor University, Iran

Abstract

Solar water heaters are good tools for saving fuel. The main component of these water heaters is collectors, which are responsible for absorbing solar energy and transferring it to the working fluid with the least heat dissipation. The present study is an experimental study of the performance of the solar semispherical collector with 1 m2 of absorber area at different volumetric flow rates. Water was used as the working fluid with the volumetric flow rate between 0.005-0.0166 kg/s, and the experiment was conducted in the ASHRAE 93 standard conditions. The results showed that the efficiency of semispherical solar collector increased as the flow rate of the working fluid increased, such that the highest efficiency, which is 67%, belonged to mass flow rate 0.0166 kg/s. In addition, the difference between outlet and inlet temperatures decreased due to the system being closed during the test. In addition, according to the experiments, the reduction of radiation and wind speed did not have any significant effect on the efficiency and outlet temperature of the collector. Finally, parameters such as inlet and outlet temperature of collector, ambient temperature, ambient radiation intensity and their effect have been investigated empirically on the collector efficiency graph.

Keywords

Main Subjects

1.     Bogaerts, W.F. and Lampert, C.M., "Materials for photo thermal solar-energy conversion", Journal of Materials Science, Vol. 18, (1983), 2847-2875. (https://doi.org/10.1007/BF00700767).
2.     Kalogirou, S., "Solar thermal collectors and applications", Progress In Energy and Combustion Science, Vol. 30, (2004), 231-295. (https://doi.org/10.1016/j.pecs.2004.02.001).
3.     Tian, Y. and Zhao, C.Y., "A review of solar collectors and thermal energy storage in solar thermal applications", Applied Energy, Vol. 104, (2013), 538-553. (https://doi.org/10.1016/ j.apenergy.2012.11.051).
4.     Abdolzadeh, M. and Mehrabian, M.A., "The optimal slope angle for solar collectors in hot and dry parts of Iran", Energy Sources, Part A, Vol. 34, (2012), 519-530. (https://doi.org/10.1080/ 15567036.2011.576413).
5.     Riffat, S., Zhao, X. and Doherrty, P.S., "Developing a theoretical model to investigate thermal performance of a thin membrane heat-pipe solar collector", Applied Thermal Engineering, Vol. 25, (2005), 899-91. (https://doi.org/10.1016/j.applthermaleng. 2004.08.010).
6.     Cruz-Peragon, F., Palomar, J.M., Casanova, P.J., Dorado, M.P. and Manzano-Agugliaro, F., "Characterization of solar flat plate collectors", Journal of Science Direct, April (2012), 1709–1720. (https://doi.org/10.1016/j.rser.2011.11.025).
7.     Esen, M. and Esen, H., "Experimental investigation of a two-phase closed thermo syphon solar water heater", Solar Energy, Vol. 79, (2005), 459-468. (https://doi.org/10.1016/j.solener. 2005.01.001).
8.     Yousefi, T., Veysi, F., Shojaeizadeh, E. and Zinadini, S., "An experimental investigation on the effect of Al2O3-H2O nanofluid on the efficiency of flat plate solar collector", Renewable Energy, Vol. 39, (2012), 293-298. (https://doi.org/10.1016/ j.renene.2011.08.056).
9.     Chen, Z., Furbo, S., Perers, B., Fan, J. and Andersen, E., "Efficiencies of flat plate solar collectors at different flow rates", Energy Procedia, Vol. 30, (2012), 65-72. (https://doi.org/ 10.1016/j.csite.2016.08.006).
10.   Kalogirou, S., "Prediction of flat plate collector performance parameters using artificial neural networks", Solar Energy, Vol. 80, (2006), 248-259. (https://doi.org/10.1016/j.solener. 2005.03.003).
11.   Kumar, N., Chavda, T. and Mistry, H.N., "A truncated pyramid non tracking type multipurpose solar cooker/hot water system", Applied Energy, Vol. 87, (2010), 471-477. (https://doi.org/ 10.1016/j.apenergy.2009.06.031).
12.   Ayompe, L.M. and Duffy, A., "Analysis of the thermal performance of a solar water heating systemwith flat plate collectors in a temperate climate", Applied Thermal Engineering, Vol. 58, (2013), 447-454. (https://doi.org/ 10.1016/j.applthermaleng.2013.04.062).
13.   Tyagi, H., Phelan, P. and Prasher, R., "Predited efficiency of a low-temperature nanfluid-based direct absorption solar collector", Journal of Solar Energy Engineering, Vol. 131, (2009), 1-7. (https://doi.org/10.1063/1.3429737).
14.   Taylor, R.A., Phelan, P.E., Otanicar, T.P., Walker, C.A., Nguyen, M., Trimble, S. and Prasher, R., "Applicability of nanofluids in high flux solar collectors", Journal of Renewable and Sustainable Energy, Vol. 3, (2011), 023104. (https://doi.org/10.1063/1.3571565).
15.   Choi, S. and Zhang, Z.G., "Anomalous thermal conductivity enhancement in nanotube suspensions", Applied Physics Letter, Vol. 79, (2001), 2252-2254. (https://doi.org/10.1063/1.1408272).
16.   Otanicar, T., Phelan, P., Parsher, R., Rosengarten, G. and Taylor, R., "Nanofluid-based direct absorption solar collector", Journal of Renewable and Sustainable Energy, Vol. 2, (2010), 033102. (https://doi.org/10.1186/1556-276X-6-225).
17.   Otanicar, P. and Golden, J., "Comparative environmental and economic analysis of conventional and nanofluid solar hot water technologies", Environmental Science and Technology, Vol. 43, (2009), 6082-6087. (https://doi.org/10.1021/es900031j).
18.   Rajabi Khanghahi, A., Zamen, M., Soufari, M., Amidpour, M. and Abbas Nejad, A.,"Theoretical investigation of consumption patterns effect on optimal orientation of collector in solar water heating system", Journal of Renewable Energy and Environment (JREE), Vol. 4, No. 1, (2017), 1-10.
19.   Mahian, O., Kianifar, A., Sahin, A. and Wongwises, S., "Performance analysis of a minichannel-based solar collector using different nanofluids", Energy Conversion and Management, Vol. 88, (2014),129-138. (https://doi.org/10.1016/ j.enconman.2014.08.021).
20.   Zamzamian, S., Keyanpour Rad, M., Kiani Neyestani, M. and Jamal-Abad, M.T., "An experimental study on the effect of Cu-synthesized/EG nanofluid on the efficiency of flat-plate solar collectors", Renewable Energy, Vol. 71, (2014), 658-664. (https://doi.org/10.1016/j.renene.2014.06.003).
21.   Jamal-Abad, M.T., Zamzamian, A., Imani, E. and Mansouri, M., "Experimental study of the performance of a flat-plate collector using Cu-water nanofluids", Journal of Thermophysics and Heat Transfer, Vol. 27, (2013), 756-760. (https://doi.org/ 10.2514/1.T4074).
22.   Mousazaeh, H., "A review of principal and sun-tracking methods for maximizing solar systems output", Renewable and Sustainable Energy Reviews, Vol. 13, (2009), 1800-1818. (https://doi.org/10.1016/j.rser.2009.01.022).
23.   Noghrehabadi, A., Hajidavaloo, E. and Moravej, M., "An experimental investigation of a 3-D solar conical collector performance at different flow rates", Journal of Heat and Mass Transfer Research, Vol. 1, (2016), 57-66. (https://doi.org/ 10.22075/JHMTR.2016.477).
24.   Bakir, O., "Experimental investigation of a spherical solar collector", Thesis submitted to the graduate School of Natural and Applied Science of Middle East Technical University, (April 2006).
25.   Iljins, U. and Ziemelis, I., "Forecast of energy received by solar collectors", Proceedings of The International Scientific Conference Applied Information and Communication Technologies, Jelgava, Latvia University of Agriculture, (2008), 62-67.
26.   Iljins, U. and Ziemelis, I., "Theoretical calculation of energy received by semi-spherical solar collector", Latvia University of Agriculture, Liela str. 2, Jelgava, LV3000.
27.   Shamim, M.A., Remesan, R., Han, D.-W., Ejaz, N. and Elahi, A., "An improved technique for global solar radiation estimation using numerical weather prediction", Journal of Atmospheric and Solar-Terrestrial Physics, Vol. 129, (2015), 13-22. (https://doi.org/10.1016/j.jastp.2015.03.011).
28.   Yousefi, T., Shojaeizadeh, E., Veysi, F. and Zinadini, S., "An experimental investigation on the effect of MWCNT-H2O nanofluid on the efficiency of flatplate solar collectors", Experimental Thermal and Fluid Science, Vol. 39, (2012), 207-212. (https://doi.org/10.4172/fundamentals-renewable-energy.1000200).
29.   Do Ango, A.M., Medale, M. and Abid, C., "Optimization of the design of a polymer flat plate solar collector", Solar Energy, Vol. 87, (2013), 64-75. (https://doi.org/10.1016/j.solener. 2012.10.006Get rights and content).
30.   Cristofari, C., Notton, G., Poggi, P. and Louche, A., "Modelling and performance of a copolymer solar water heating collector", Solar Energy, Vol. 72, (2002), 99-112. (https://doi.org/10.1016/ S0038-092X(01)00092-5).
31.   Sen, Z., Solar energy fundamentals and modeling techniques, Springers, (2008).
32.   Mohammadi, K. and Khorasanizadeh, H., "A review of solar radiation on vertically mounted solar surfaces and proper azimuth angles in six Iranian major cities", Renewable and Sustainable Energy Reviews, No. 47, (2015), 504-518. (https://doi.org/10.1016/j.rser.2015.03.037).
33.   ASHRAE Standard 93-86, Methods of testing and determine the thermal performance of solar collectors, ASHRAE, Atlanta (2003).
34.   Duffie, J.A. and Beckman, W.A., Solar engineering of thermal processes, 4th Ed., Wiley, New York, (2013).
35.   Rojas, D., Beermann, J., Klein, S. and Reindl, D., "Thermal performance testing of flat plate collectors", Solar Energy, Vol. 82, (2008), 746-757. (https://doi.org/10.1016/j.solener. 2008.02.001).
36.   Abernethy, R., Benedict, R. and Dowdell, R., "ASME measurement uncertainty", ASME paper, (1983), 83-WA/FM-3.
37.   Ma, J., Sun, W., Ji, J., Zhang, Y., Zhang, A. and Fan, W., "Experimental and theoretical study of the efficiency of a dual-function solar collector", Applied Thermal Engineering, Vol. 31, (2011), 1751-1756. (https://doi.org/10.1016/ j.applthermaleng.2011.02.019).
38.   Tongtuama, Y., Ketjoya, N., Vaivudha, S. and Thanaraka, P., "Effect of the diffuse radiation reflection from exterior wall on shading device integrated photovoltaic case of Thailand building", Energy Procedia, No. 9, (2011), 104-116. (https://doi.org/10.1016/j.egypro.2011.09.012).
39.   Boland, J., Huang, J. and Ridley, B., "Decomposing global solar radiation into its direct and diffuse components", Renewable and Sustainable Energy Reviews,Vol. 28, (2013), 749-756. (https://doi.org/10.1016/j.rser.2013.08.023).
40.   Goudarzi, K., Asadi Yousef-Abad, S., Shojaeizadeh, E. and Hajipour, A., "Experimental investigation of thermal performance in an advanced solar collector with spiral tube", International Journal of Engineering-Transactions A: Basics, Vol. 27, (2013), 1149.
41.   Ranjbar, S. and Seyyedvalilu, M., "The effect of geometrical parameters on heat transfer coefficient in helical double tube exchangers", Journal of Heat and Mass Transfer Research (JHMTR), Vol. 1, (2014), 75-82. (https://doi.org/10.22075/ JHMTR.2014.182).