Experimental Study on The Effect of Wind on Heat Losses from a Fully Open Cylindrical Cavity with only Bottom Wall Heated

Abstract

An experimental study using electrical heating method has been performed to explore the impact of wind speed, wind incidence angle as well as cavity inclination on the heat losses from a fully open cylindrical cavity with only bottom wall heated at constant heat flux. The cavity under different inclinations is subjected to four different wind speeds of 1.15, 1.84, 2.94, 5.69 m/s, and wind incidence angles from 0° (wind blowing parallel to cavity aperture plane) to 90° (wind blowing vertically to cavity aperture plane) at intervals of 30°. Results reveal that, the average temperature of cavity wall decreases with increasing wind speed and wind incidence angle. The combined convection heat loss increases obviously with the increase of wind speed, while the radiation and conduction heat losses decrease for all wind incidence angles. The variations of convection heat loss with the cavity inclination at constant heat flux boundary condition are quite different from that at constant wall temperature boundary condition. The combined free-forced convection heat loss Nusselt number Nuc is more sensitive to the wind speed and wind incidence angle in comparison with the radiation heat loss Nusselt number Nur. In addition, new correlations of Nusselt numbers have been developed to estimate the convection heat loss and radiation heat loss due to the environmental wind.