ISSN Online: 2377-424X
ISBN Print: 0-89116-299-2
International Heat Transfer Conference 7
EFFECT OF SECONDARY FLOW ON HEAT TRANSFER IN SOLAR COLLECTOR TUBES
Resumo
A transient two-dimensional model is developed for studying the effect of secondary flow on heat transfer in horizontal circular tubes subjected to peripherally sinusoidal heat flux and axially uniform wall heat flux. Computations have been performed upto Gr+ = 106 showing the velocity and temperature profiles on horizontal and vertical planes and the time-wise development of streamlines and isotherms. The horizontal profile at Gr+ = 106 approaches the free convection pattern.
Experimental investigation has been carried out
for air flowing in a 26.2 mm dia. eccentrically
turned stainless steel tube with electrical heating.
Velocity and temperature of air in the horizontal
and vertical planes are measured at different
axial positions. There is good agreement
between the computed and measured profiles.
Nusselt number evaluated from the analytical model
and those obtained experimentally are compared.