Simulation of a V-Corrugated Solar Air Heater
Keywords:
Solar Energy, Air Heater, Computer SimulationAbstract
The performance characteristics of a V-corrugated plate type solar air heater was investigated analytically using computer simulation. A Visual Basic computer program was built to predict the hourly instantaneous collection efficiency, useful energy gained and the outlet air temperature of the solar air heater. The effects of various design and operating conditions, such as mass flux, wind speed, absorber plate emissivity, and collector tilt angle and inlet air temperature, on the predicted values were examined. Results of the simulation of the solar air heater indicated that increasing mass flux of the air through the collector increases the instantaneous efficiency and the useful energy gained but reduces the air outlet temperature rapidly. An air outlet temperature of about 69°C was obtained in winter at midday at a mass flux of 0.1kg/s.m2 with an average collection efficiency of 34%. Also, it was found that absorber plate emissivity, and (inlet-ambient) temperature difference affect the solar air heater performance in varying degrees. An optimum tilt angle in Jalu for the solar air heater during the period from May to August and from November To February was found to be equal to 5°, 50 from the horizon, respectively. Also, changing the tilt angle by ±10° around its optimum value reduces the useful energy gained by only 2% during the same period in summer and winter. Experimental data of previous work were compared with the simulation results and found in very good agreement.
Downloads
References
K. G. T. Hollands, "Air heating flat plate solar collectors", Solar Energy Conversion II: Selected Lectures, edited by A. F. Janzen and R. K. Swartman, pp. 65-72, Pergamon Press, Toronto, (1980).
N. K. Dhiman and G. N. Tiwari, "Performance of a two channel suspended flat plate solar air heater", Energy Convers. Mgmt., Vol. 24, No. 4, pp. 269-275, (1984).
M. R. Diab, J. T. Pearson and R. Viskanta, "A two dimensional analysis of flat plate air-heating solar collectors", Trans. of the ASME, 80-HT-117, (1980).
P. Biondi, L. Cicala and G. Farina, "Performance analysis of solar air heaters of conventional design", Solar Energy, Vol. 41, No. 1, pp. 101-107, (1988).
Indrajit, N. K. Bansal and H. P. Garg, "An experimental study on a finned type and non-porous type solar air heater with a solar simulator", Energy Convers. Mgmt., Vol. 25, No. 2, pp. 135-138, (1985).
F. H. Buelow and J. J. Boyd, " Heating air by solar energy", Agri. Engg., Vol. 38, No. 1, pp. 28-30, (1957).
K. G. T. Hollands, " Directional selectivity, emittance and absorptance properties of V- corrugated specular surfaces", Solar Energy, Vol. 7, No. 3, pp. 108-116, (1963).
A. A. M. Sayigh, Solar Energy Engineering, Academic Press, London, (1977).
K. G. T. Hollands and E. C. Shewen, " Optimization of flow passage geometry for air- heating, plate- type solar collectors", Trans. of the ASME, J. of Solar Energy Engineering, Vol. 103, pp. 323-330, (Nov. 1981).
K. A. Joudi and A. I. Mohammed, " Experimental performance of a solar air heater with a V- corrugated absorber, Energy Convers. Mgmt., Vol. 26, No. 2, pp. 193-200, (1986).
J. A. Duffie and W. A. Beckman, Solar Engineering of Thermal Processes, John Wiley & Sons, New York, (1980).
W. C. Swinbank, " Long wave radiation from clear skies", Quarterly J. of Royal Meteorological Society, Vol. 89, pp. 339, (1963).
B. A. Meyer, K. R. Randall, M. M. El- Wakil and J. W. Mitchell, " Interferometric investigation of convection in slat, flat plate and Vee- corrugated solar collectors", Solar Energy International Progress, Vol. 1, edited by T. Nejat Veziroglu, Pergamon Press, pp. 446-462, (1978).
S. K. Samdarshi and S. C. Mullick, " Generalized analytical equation for the top heat loss factor of a flat- plate solar collector with N glass covers", Trans. of the ASME, J. of Solar Energy Engineering, Vol. 116, pp. 43-46, (Feb. 1994).
P. J. Lunde, Solar Thermal Engineering, John Wiley & Sons, New York, (1980).
ASHRAE Handbook of Fundamental, American Society of Heating, Refrigerating and Air Conditioning Engineers, Inc., New York, (1985).
K. A. Joudi, " Some aspects of solar irradiance calculation", Proceedings of the Third Arab International Solar Energy Conference, edited by N. I. Al- Hamdani, S. A. Naman, S. M. Aliiwi, W. Y. Saman and A. A. Akrawi, Solar Energy Research Center, Baghdad, (Feb. 1988).
Edward E. Anderson, Fundamentals of Solar Energy Conversion, Addison- Wesley Pub. Co., New York, (1983).
S. A. Klein, J. A. Duffie and W. A. Beckman, "Transient considerations of flat plate solar collectors", Trans. of the ASME, J. of Engineering for Power, Vol. 96 A, No. 2, pp. 109-113, (1974).
S. A. Klein, " Calculation of monthly average insolation on tilted surfaces", Solar Energy, Vol. 6, pp. 325-329, (1979).
