An improved technique for computing the top heat loss factor of a flatplate collector with a single glazing
Abstract
A different approach to evaluate the top heat loss factor of a flat plate solar collector with a single glass cover is proposed. The equation for the heat loss factor in the analytical form is employed instead of the semiempirical form hitherto employed for solar collectors. The glass cover temperature is, however, estimated by an empirical relation. (This relation replaces the empirical relation for the factor f of the earlier work). Values of the top heat loss factor calculated by this simple technique are within 3 percent (maximum error) of those obtained by iterative solution of the heat balance equations. There is an improvement in accuracy by a factor greater than five over the current semiempirical equations. The range of variables covered is 50/sup 0/C to 150/sup 0/C in absorber plate temperature, 0.1 to 0.95 in absorber coating emittance, and 5 W/m/sup 2/C to 45 W/m/sup 2/C in wind heattransfer coefficient. The effect of variation in air properties with temperature has been taken into account.
 Authors:
 Publication Date:
 Research Org.:
 Centre for Energy Studies, Indian Institute of Technology, Delhi, New Delhi 110 016 (IN)
 OSTI Identifier:
 6429940
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: J. Sol. Energy Eng.; (United States); Journal Volume: 110:4
 Country of Publication:
 United States
 Language:
 English
 Subject:
 14 SOLAR ENERGY; 42 ENGINEERING; FLAT PLATE COLLECTORS; HEAT LOSSES; AIR; ANALYTICAL SOLUTION; CALCULATION METHODS; DESIGN; EQUATIONS; GLAZING; ITERATIVE METHODS; VARIATIONS; COVERINGS; ENERGY LOSSES; EQUIPMENT; FLUIDS; GASES; LOSSES; SOLAR COLLECTORS; SOLAR EQUIPMENT; 141000*  Solar Collectors & Concentrators; 420400  Engineering Heat Transfer & Fluid Flow
Citation Formats
Mullick, S.C., and Samdarshi, S.K. An improved technique for computing the top heat loss factor of a flatplate collector with a single glazing. United States: N. p., 1988.
Web. doi:10.1115/1.3268266.
Mullick, S.C., & Samdarshi, S.K. An improved technique for computing the top heat loss factor of a flatplate collector with a single glazing. United States. doi:10.1115/1.3268266.
Mullick, S.C., and Samdarshi, S.K. Tue .
"An improved technique for computing the top heat loss factor of a flatplate collector with a single glazing". United States.
doi:10.1115/1.3268266.
@article{osti_6429940,
title = {An improved technique for computing the top heat loss factor of a flatplate collector with a single glazing},
author = {Mullick, S.C. and Samdarshi, S.K.},
abstractNote = {A different approach to evaluate the top heat loss factor of a flat plate solar collector with a single glass cover is proposed. The equation for the heat loss factor in the analytical form is employed instead of the semiempirical form hitherto employed for solar collectors. The glass cover temperature is, however, estimated by an empirical relation. (This relation replaces the empirical relation for the factor f of the earlier work). Values of the top heat loss factor calculated by this simple technique are within 3 percent (maximum error) of those obtained by iterative solution of the heat balance equations. There is an improvement in accuracy by a factor greater than five over the current semiempirical equations. The range of variables covered is 50/sup 0/C to 150/sup 0/C in absorber plate temperature, 0.1 to 0.95 in absorber coating emittance, and 5 W/m/sup 2/C to 45 W/m/sup 2/C in wind heattransfer coefficient. The effect of variation in air properties with temperature has been taken into account.},
doi = {10.1115/1.3268266},
journal = {J. Sol. Energy Eng.; (United States)},
number = ,
volume = 110:4,
place = {United States},
year = {Tue Nov 01 00:00:00 EST 1988},
month = {Tue Nov 01 00:00:00 EST 1988}
}

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