화학공학소재연구정보센터
Chemical Engineering and Processing, Vol.120, 114-133, 2017
Effect of multiple arc protrusion ribs on heat transfer and fluid flow of a circular-jet impingement solar air passage
Results from experimental study of the heat and fluid flow characteristics of circular-jet impingement solar air passage are presented. The testing includes the turbulent flow Reynolds number (Re) from 5000 to 19,000, relative width ratio (W-P/W-AP) from 1.0 to 6.0, relative pitch ratio (P-P/e(P)) from 8.0 to 12, relative height ratio (e(P)/d(P)) from 0.5 to 2.0, angle of arc (alpha(alpha)) from 35 degrees to 75 degrees, for the fixed values of stream wise pitch ratio(X-S/d(H)) of 0.433, span wise pitch ratio(Y-S/d(H)) of 0.866 and jet diameter ratio (D-j/d(H))of 0.065. The maximum enhancement in heat transfer and friction factor has been observed to be 6.29 and 9.25 times to that of smooth absorber plate. The optimum value of thermal performance has been found corresponds to W-P/W-AP = 5.0, P-P/e(P) = 9.5, e(P)/d(P) = 1.0, alpha(alpha) = 55, X-S/d(H) = 0.433, Y-S/d(H) = 0.866 and D-j/d(H) = 0.065. The optimum value of thermal hydraulic performance has been found to be 3.64 for Re of 13,000 within the range of the parameter investigated.