The Effect of Collector Aspect Ratio on the Collector Efficiency of Sheet-and-Tube Solar Fluid Heaters

Ho-Ming Yeh; Chii-Dong Ho; Chun-Hung Chen

doi:10.6180/jase.1999.2.2.02

The Effect of Collector Aspect Ratio on the Collector Efficiency of Sheet-and-Tube Solar Fluid Heaters

Chemical Engineering

Ho-Ming Yeh¹, Chii-Dong Ho¹ and Chun-Hung Chen¹

¹Department of Chemical Engineering Tamkang University Tamsui, Taipei, Taiwan 251

Received: June 6, 1999
Accepted: October 26, 1999
Publication Date: October 26, 1999

Download Citation: ||https://doi.org/10.6180/jase.1999.2.2.02

ABSTRACT

The influence of collector aspect ratio on the collector efficiency of sheet-and-tube solar fluid heaters has been investigated theoretically. With constant collector area and the distance between tubes, the collector efficiency increases with increasing collector aspect ratio (i.e., either increasing l or decreasing n) as well as with decreasing the inlet temperature for air or water flowing through the tubes. This is the same result as those obtained in the previous work for upward-type or downward-type flat-plate solar fluid heaters.

Keywords: solar heater, aspect ratio, collector efficiency

REFERENCES

[1] Bliss, R. W., “The Derivations of Several Plate-Efficiency Factors Useful in the Design of Flat-Plate Solar Heat Collectors,” Solar Energy, Vol.3, pp. 55 (1959).
[2] Duffie, J. A. and Beckman, W. A., Solar Engineering of Thermal Processes, 3rd ed., pp. 223, pp. 238, pp. 245 and pp. 705, Wiley, New York (1977).
[3] Hottel, H. C. and Whillier, A., Transaction of the Conference on the Use of Solar Energy, Part I, pp. 74-78, University of Arizona Press (1958).
[4] Hottel, H. C. and Woetz, B. B., Transaction of the American of Society Mechanical Engineering, Vol. 64, 91 (1942).
[5] Klein, S. A. and Klein, S. A., “Calculation of Flat-Plate Loss Coefficients,” Solar Energy, Vol. 17, 79 (1975).
[6] Kreith, F. and Kreider, J. F., Principles of Solar Engineering, Chap. 4, pp. 203-309, McGraw-Hill, New York (1978).
[7] McAdams, W. H., Heat Transmission, 3rd ed., McGraw-Hill, New York (1954).
[8] Seluck, M. K., Solar Air Heaters and Their Applications, A. A. M. Sayigh ed., pp. 155-182, Academic Press, New York (1977).
[9] Whillier, A., Applications of Solar Energy for Heating and Cooling of Buildings, ASHRAE, New York, pp. 27-40 (1977).
[10] Yeh, H. M. and Lin, T. T., “The Effect of Collector Aspect Ratio on the Collector Efficiency of Flat-Plate Solar Air Heaters,” Energy, Vol. 20, 1041 (1995).
[11] Yeh, H. M., “Theory of Baffled Solar Air Heaters,” Energy, Vol. 17, 697 (1992).
[12] Yeh, H. M. and Ting, Y. C., “The Effect of Free Convection on Collector Efficiency of Solar Air Heaters,” Applied Energy, Vol. 22, 145 (1986).
[13] Yeh, H. M. and Ting, Y. C., “Efficiency of Solar Air Heaters Oacked with Iron Filings,” Energy, Vol. 13, 543 (1988).