Developing laminar flow and heat transfer in a rectangular duct with one-walled injection and suction

Improved Transfer Coefficients for Wall-Flow Monolithic Catalytic Reactors: Energy and Momentum Transport

“…Substitution of the above relations to the system of eqs – leads to the system –, which proves that the models of refs and are formally equivalent, and they differ only in their use of alternative definitions of the (effective) heat/enthalpy transfer coefficient. This duality of the heat transfer coefficient and correspondingly of Nusselt numbers for similar problems is also indicated in refs and . Comparing Nu K and Nu c , we note that Nu c captures the effects of heat conduction alone, while Nu K also accounts for the convective transport of enthalpy, which is already easily included separately in 1-D channel equations as described above.…”

“…Previous studies of transport properties in square channels refer to cases of only one porous wall (in contrast to the case of four porous walls in the present work) with application to fuels cells. , The three-dimensional problem (no derivation of the self-similar problem was pursued) has been solved numerically in refs and , and correlations have been derived for the Nusselt number (but only for a specific value of Prandtl number). Recently, an approximate solution for the flow field in a channel with one porous wall and high aspect ratio has been developed, but no correlations for integral properties like the friction factor have been presented .…”

“…Recently, an approximate solution for the flow field in a channel with one porous wall and high aspect ratio has been developed, but no correlations for integral properties like the friction factor have been presented . The data from studies considering only one porous wall , have been previously used to suggest correlations for DPF modeling . However, the flow with one porous wall does not approximate the distinctly different flow with 4 porous walls, and, additionally, the derived correlations are restricted to Prandtl number equals 0.72.…”

Cooling transients in a sudden-expansion channel with varied rates of wall transpiration

“…On the other hand, the flow structure was observed to alter on increasing the fluid injection from the bottom wall. Collier and Schetz [9] indicated that the turbulence intensity and the Reynolds stress in the turbulent boundary layer were enhanced, while Cheng et al [10] claimed that the pressure loss and the friction coefficient were both enlarged, though the heat transfer at the bottom wall was decreased. Similarly, the influence of the wall injection (with transpiration rates of 0-2%) upon the turbulence intensity, the characteristics of the boundary layer, and the friction coefficient of the wall was investigated by Rodet et al [11].…”

Entropy analysis for heat transfer in a rectangular channel with suction

“…Brailovskaya examined experimentally the turbulent transition flow in annular channels and pipes. Many researchers (Hwang and Cheng, Song and Sundmacher, Cheng and Hwang, Chabani et al and Ahmed Bahlaoui et al) have attempted to study viscous flow in a rectangular tube with suction at the opposite walls. Varapaev and Yagodkin have studied the effect of suction at the neighboring walls of a rectangular tube, wherein the solution was obtained only for the flow pattern by a seminumerical technique.…”