Thus, the main aim of the present work is to investigate the heat transfer and flow friction characteristics in a channel equipped with X-shape baffle. that may reduce pressure drop compare with other baffle.
The ribs are placed only on the absorber plate with a single rib height, e/H=0.20 and rib pitch, Pl/H=1.33. The use of multiple DWs (ten pairs) fitted at the entrance of the tested channel is expected to create multiple longitudinal vortex flows in order to prolong the residence time of the flow and to wash up the reverse flow trapped behind the ribs leading to higher heat transfer rate in the channel. The present results are also compared with the results from the single use of the DWs or the ribs alone. Experimental results using air as the test fluid from the rib and theDWwith three angles of attack (α=60°, 45° and 30°) and two arrangements of the DW; pointing upstream (PU) and pointing downstream (PD) are presented in turbulent channel flows in a range of Reynolds number from 5000 to 22,000.