Analysis of conjugate heat transfer for forced convective flow through wavy minichannel

Abstract

Purpose The purpose of this paper is to analyze numerically forced convective conjugate heat transfer characteristics for laminar flow through a wavy minichannel. Design/methodology/approach The mass and momentum conservation equations for the flow of water in the fluidic domain and the coupled energy conservation equations in both the fluid and solid domain are solved numerically using the finite element method. The exteriors of both the walls are subjected to a uniform heat flux. Findings The results reveal that the theoretical model without consideration of the effect of wall thickness always predicts a lower value of average Nusselt number ( Nu¯) as compared to the case of conjugate analysis, although it varies with the thickness as well as material of the wall. For the low amplitude of the wall (α = 0.2), the performance factor (PF) becomes very high for Re in the regime of 5 (⩽) Re (⩽) 15. For any geometrical configurations, conjugate heat transfer analysis predicts higher PF as compared to that of nonconjugate analysis. Practical implications The present study finds relevance in several applications, such as solar collectors and heat exchangers used in chemical industries and heating-ventilation and air-conditioning, etc. Originality/value To the best of the authors’ knowledge, the analysis of combined influences of the thickness and the material of the wall of the channel together with the geometrical parameters of the channel, namely, amplitude and wavelength on the heat transfer and fluid flow characteristics for flow through wavy minichannel in the laminar regime is reported first time in the literature.

Analysis of hydrothermal performance for laminar forced convective flow through a wavy channel with porous blocks

“…The flow is laminar, steady and incompressible. The width of the channel is quite large as compared to the height and the laminar flow allows 2D governing equations to investigate temperature and flow fields within the channel (Borah et al, 2022). Radiation and viscous dissipation effects are neglected.…”

“…The following assumptions are invoked for the present numerical study (Ashorynejad and Zarghami, 2018; Pati et al , 2017; Wang and Chen, 2002; Kim and Jang, 2002; Lee and Vafai, 1999; Calmidi and Mahajan, 2000; Bhowmick et al , 2021). The flow is laminar, steady and incompressible. The width of the channel is quite large as compared to the height and the laminar flow allows 2D governing equations to investigate temperature and flow fields within the channel (Borah et al , 2022). Radiation and viscous dissipation effects are neglected. The porous material is isentropic and homogeneous.…”

“…The width of the channel is quite large as compared to the height and the laminar flow allows 2D governing equations to investigate temperature and flow fields within the channel (Borah et al , 2022).…”

“…Mehta et al (2022b) computationally analyzed the hydrothermal performance for flow through a ribbed wavy channel by varying the number of ribbed and their shape: rectangular, semi-circular and triangular and observed that the rectangular ribbed-wavy channel has a higher performance factor among all the configurations in the regime: 50 # Re # 125. Additionally, numerous recent research investigations relating to heat transfer enhancement have been conducted using the irregular geometries, such as the 60°C hevron plate heat exchanger (Singh and Ghosh, 2022), wavy porous layer (Ouni et al, 2022), wavy surface with finite wall thickness (Borah et al, 2022), wavy channel with linearly varying amplitude (Kumar et al, 2022a(Kumar et al, , 2022b and novel wavy fin-and-circle tube heat exchanger having concave curved vortex generators (Song et al, 2022).…”

Investigation of an improved cold plate design with circuitous minichannel: a computational study involving the effect of conjugate heat transfer

“…However, this effect of axial wall conduction or axial back conduction is not analysed while designing the MCPs reported in the literature. The solid-to-fluid thermal conductivity ratio and substrate thickness-to-channel height ratio must be considered to evaluate the optimum design parameters and temperature uniformity (Borah et al , 2022; Tiwari and Moharana, 2020). Most of these profile modifications of minichannel proposed by the authors are complex from a manufacturing and design point of view, making its practical deployment challenging and higher manufacturing cost.…”