Boundary Plate Thickness Research Articles

Mixed convection flow in a vertical channel in the presence of wall conduction, variable thermal conductivity and viscosity

AbstractThis study theoretically investigates the effects of variable viscosity, thermal conductivity and wall conduction on a steady mixed convection flow of heat generating/absorbing fluid passes through a vertical channel. One of the channel plates moves with a constant velocity while the other is stationary. The governing flow equations are solved analytically using homotopy perturbation method (HPM). The effects of the thermophysical and hydrodynamics parameters are captured in graphs and tables. It has been observed that, both the velocity and temperature distributions decrease with increase in viscosity and boundary plate thickness near the heated plate while a reverse cases were observed near the cold plate. Increase in thermal conductivity ε decreases the fluid flow near the heated plate. When the boundary plate thickness is increased, the critical value of Gre to onset the reverse flow increases while increase in thermal conductivity reduces the critical value of Gre. It’s also noticed that the skin friction and rate of heat transfer at the heated plate decrease with increase in boundary plate thickness d.

Effects of viscous dissipation and boundary wall thickness on steady natural convection Couette flow with variable viscosity and thermal conductivity

Abstract This study theoretically examines the effects of boundary plate thickness and viscous dissipation on a steady natural convection flow of an incompressible viscous fluid of variable properties. This is due to the fact that several investigations in literature have neglected the thickness and material composition of the boundary plates and as such, their results are either over-determined or under-determined. The viscosity and thermal conductivity of the heat generating/absorbing fluid were assumed to be functions of temperature. Due to the nonlinearity and coupling nature of the governing flow equations, homotopy perturbation method (HPM) has been used to solve the problem. The effects of the thermophysical and flow parameters were captured in graphs and tables. It has been discovered from the study that the velocity profile increases with increase in thermal conductivity. Increase in boundary plate thickness ( d ) was found to boost the fluid flow across the medium while the temperature decreases near the heated plate. It’s further observed that the skin friction decreases on both plates with increase in fluid viscosity and boundary plate thickness ( d ) while the rate of heat transfer decreases on both the plates with an increase in boundary plate thickness ( d ). The volume flow rate is discovered to increase with increase in Brinkman number ( B r ) while a decrease was observed with increase in boundary plate thickness ( d ).

Steady natural convection Couette flow with wall conduction and thermal boundary condition of third kind

AbstractThis study theoretically investigates the effects of viscous dissipation and boundary plate thickness on an incompressible heat generating/absorbing fluid with non‐uniform internal temperature unlike lumped heat capacitance assumption. The flow, which is laminar is induced by free convection caused by asymmetric heating of the channel boundaries and internally generated energy caused by viscous dissipation. In addition, convection through the boundary plates is also considered in the flow formation. One of the plates channel moves along the flow direction while the other is stationary. Due to the non‐linear and coupling nature of the governing flow equations, homotopy perturbation method (HPM) has been adopted to analytically find the approximate solution to the problem. The effects of thermodynamic and hydrodynamic parameters are depicted in graphs and tables. It is discovered from the investigation that, both the velocity and temperature profiles increase with increase in viscous dissipation. Velocity distribution decreases with increase in Biot number while the temperature distribution near the heated plate increases with increase in Biot number. The increase in boundary plate thickness d causes a boost in the fluid flow across the medium and reduces the temperature of the fluid near the heated plate. It is further discovered that the rate of heat transfer on both plates increase with increase in Biot number while they drastically dropped when the boundary plate thickness d is increased. The shear stresses on the surface of both plates increase with increase in heat generation while reverse cases were observed with increase in heat absorption . It is further observed that the volume flow rate within the channel increases with increase in viscous dissipation .

Effects of Viscous Dissipation and Wall Conduction on Steady Mixed Convection Couette Flow of Heat Generating/Absorbing Fluid

This article theoretically investigated mixed convection flow of heat generating/absorbing fluid in the presence of viscous dissipation and wall conduction effects. The flow is considered to be steady in a vertical channel with some boundary thickness. One of the plates is heated while the other is kept at ambient temperature. The governing flow equations were solved analytically using Homotopy Perturbation Method (HPM). The influences of the governing parameters were captured in graphs, tables and a table was constructed for validation of the work. It is worthwhile to stress that, both the velocity and temperature profiles decrease near the heated plate with an increase in boundary thickness (<i>d</i>) while the reverse cases were observed toward the cold plate. The velocity profile increases near the heated plate with increase in mixed convection parameter (<i>Gre</i>) and decreases towards the cold plate. Rate of heat transfer has been observed to decrease with increase in boundary plate thickness (<i>d</i>) while the critical value of (<i>Gre</i>) increases with growing boundary plate thickness. The study therefore established the importance of boundary plate thickness in mixed convection investigation.