Heat transfer in channel flow around a rectangular cylinder

Abstract

Heat transfer and flow visualization experiments have been made in a channel with a rectangular cylindrical section having various width-to-height ratios. Vortices were observed to shed periodically from the cylinder and then reattach to the channel wall. This reattachment of the vortices induces a periodic fluctuation in heat flux at the wall and enhances the heat transfer in the downstream region of the cylinder. The streamwise position of the maximum Nusselt number moves downstream with decreasing width-to-height ratio, b/h, of the cylinder. When b/h = 2.0, however, the heat flux periodicity disappears because the wake narrows intermittently owing to reattachment of the separated flows to the upper and lower surfaces of the cylinder. © 1998 Scripta Technica. Heat Trans Jpn Res, 27(1): [84][85][86][87][88][89][90][91][92][93][94] 1998

Experimental Study of Near Wake Flow Behind a Rectangular Cylinder

“…The same Strouhal number can be seen for present work and the references [2,3,5] according to table 1. Figure 9 shows the U spectra at locations x * = 2 and 3.5 for two y plane in the wake of a square cylinder at Reynolds number of 8600.…”

“…Their experimental results showed a relationship between the flow topology and the turbulence distribution. Yao et al [4] and Nakagava et al [5] confirmed that the periodically shed vortices from the cylinder enhance the heat transfer at the downstream channel wall. A simultaneous measurement of the velocity and temperature fluctuation using the hot and cold wires was conducted by Yao et al [4] .…”

“…Nakagava et al [5] showed that for the channel flow, depending on the width-to-height ratio (b h −1 ) of the rectangular cylinder, heat transfer characteristics change significantly. They conducted their experiments in a blockage ratio of 0.2.…”

“…This would be attributed to the strong shed vortices which persist downstream at farther downstream region compared to the other cases [5] .…”

Effects of different fuel supply types on combustion characteristics behind group of V-gutter flame holders: Experimental and numerical study

“…There is a large variety of bluff bodies shapes and surface configurations which have been studied experimentally [18][19][20][21][22][23][24][25] or by and using numerical simulation methods [25,26]. The main task in such studies is to reveal the effect of the cross-section area reduction ratio, the flow structure, and consequently their effects on the fuel mixing process.…”