TRANSIENT FORCED-CONVECTION HEAT-TRANSFER IN A VERTICAL RIB-HEATED CHANNEL USING A TURBULENCE PROMOTER

An experimental investigation for transient forced convection heat transfer in a vertical rib-heated channel with a turbulence promoter has been systematically performed. Parametric studies including the steady-state convective heat flux, channel inlet velocity, channel spacing, and promoter location and height on transient heat transfer performance in a vertical rib-heated channel have been explored. A generalized distribution for transient convective heat flux is proposed; the channel inlet velocity is verified to be the most significant parameter affecting transient convective heat flux and Nusselt number distributions. Besides, the use of a turbulence promoter can effectively enhance transient heat transfer performances for all the ribs in both the entrance and the fully-developed regions of the channel. Furthermore, the present results reveal that the effect of channel inlet velocity is more significant on the heat transfer performance of ribs in the entrance region than in the fully-developed region of the channel, while the effect of promoter height is reverse. The effect of promoter height compared with that of promoter location has more significance on heat transfer performance in the fully-developed region.