Heat Transfer Enhancement in a High Aspect Ratio Channel with System Optimization

Abstract

Outdoor digital information display (DID) installed near public areas has become a very popular medium of communication. Cooling performance of an outdoor DID system has become a critical issue from increasing system temperature due to heat generation at the back panel, in addition to irradiation from the sunlight. Gap distance between the heating plate and glass could control the main heat transfer rate considering its positive or negative effect on the pressure and temperature gradient at the wall. Additional reduction of maximum surface temperature can be achieved using tapered geometry with increased inlet gap distance, as well as guide vane installation at the system exit to lower pressure loss. Full system optimization has also been performed, including correlation for tapered geometry and guide vane effect. With system optimization, we can find the optimal gap clearance of parallel or tapered geometry for best performance.