Convective Heat Transfer Enhancement and Entropy Generation of Laminar Flow of Water through a Wavy Channel

Abstract

Using computational analysis, convective heat transfer enhancement and entropy generation of laminar flows through wavy channels was examined. A three-dimensional geometry was used for simulation. The simulation was performed using non dimensional governing equations for a steady laminar flow. The flow is both thermally and hydrodynamically developing while the channel walls are kept at a constant temperature. The computations were conducted with Reynolds number ranging from 100 to 2000 using water (Pr = 7.0) as the working fluid. The numerical simulation was carried out by using two different diameter ratio (W = L/D) and three different wave ratio (Y = P/D) to reach the optimal geometry with the maximum performance evaluation criterion. The results showed that the heat transfer performance in wavy channel was enhanced than a typical circular channel. The pressure drop also increased in case of wavy channel and smaller wave ratio has more friction penalty. Generally, the heat transfer performance of wavy channel has an enhanced heat transfer performance because of the thermal boundary layer disturbance and block of longitudinal heat transfer.

Irreversibility analysis for a mixed convective flow of a reactive couple stress fluid flow through channel saturated porous materials

“…The Adomial polynomials can be obtained by the Taylor's expansion of the series in (16). Then the zeroth order approximation becomes:   The partial sums in (19) are then utilized in (9)- (10) to compute the entropy generation and the Bejan profiles provided in the following section.…”

“…Zelalem et al, [10] discussed the fluid flow and heat transfer of couple stress fluid through parallel walls endowed with extended porous materials. Interested readers can see [11][12][13][14][15][16] for more significant results on couple stress fluid flow.…”

Experimental and numerical analysis of forced convection in a twisted tube

“…Obviously, the radiative heat transfer does either not play a role in the present application at low temperatures with a practically non- participating medium [28]. The turbulence is modelled within RANS applying a turbulent viscosity model, in particular, the transitional SST model of turbulence of Menter [see 29], which was successfully used, previously, in various applications in fluids and thermal engineering [30][31][32][33][34]. Oclon et al [32] used this model for heat transfer predictions in conjunction with the prediction of fouling in fin-and-tube heat exchanger, whereas Kadiyala and Chattopadhyay [34] applied the model for studying the effects of cooling jets on moving surface.…”

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“…To evaluate the effect of heat transfer enhancement under given pumping power, the performance evaluation criteria η (Bhattacharyya et al [35]) is determined as…”