Effects of Axial Jet-to-Wall Distance on Flow Behavior and Heat Transfer of a Wall Jet at Low Reynolds Number

This study investigates the flow patterns and heat transfer of wall jet. The axial jet-to-plate distances were ranged from 0 to 6. The flow visualization technique was used to obtain the instantaneous smoke flow patterns. The hotwire anemometer was used to measure the mean velocities and turbulent intensities of the wall jet. A numerical simulation was conducted to examine heat transfer characteristics. The jet flowing over the flat plate evolves vortical structures. The formation length decreases with increasing axial jet-to-wall distances. The distributions of turbulent intensity along jet axis exhibit two increasing edges at the locations where the vortex ring evolves and the breaks up. The relationship between the characteristic flow behaviors and heat transfer characteristics are revealed and discussed in the present study.