Computational Fluid Dynamics Analysis of Mixed Convection Heat Transfer and Fluid Flow in a Lid-driven Square Cavity Subjected to Different Heating Conditions

Obalalu²,

Ibitoye

et al. 2023

Heat Trans

A numerical study of mixed convective heat transfer in a lid‐driven square enclosure containing a hot elliptic cylinder is conducted. The impacts of the Grashof number , Reynolds number , cylinder tilt angle , and aspect ratio have been examined for a fluid of of 0.71. The horizontal enclosure walls are insulated, while its vertical walls are restricted to a nonvarying temperature Tc, whereas a sinusoidal temperature of is imposed on the wall of the elliptical cylinder. The governing equations are solved using COMSOL Multiphysics 5.6 software. The fluid dynamic and the heat transport profiles between the enclosure and the elliptical cylinder walls are represented by the stream function, isothermal contours, and average Nusselt number. Results established that for all the considered aspect ratios, the thermal heating range of is predominantly a conduction mechanism. The critical position of the ellipse where the inclination effect becomes insignificant is determined by the Grashof number and aspect ratio when the Re = 100. The strength of vortices and cell numbers are significantly influenced by the aspect ratio, particularly when the . When , the average heat transfer from the cylinder remains the same regardless of the cylinder's orientation. The impact of cylinder orientation on heat transfer from the cylinder wall is minimal for . For AR values of , increasing the inclination angle does not result in improved heat transfer. The influence of the increasing inclination angle on the right wall diminishes as the angle increases, except when the Grashof number is greater than 105, where the rate of heat transfer is enhanced for inclination angles beyond 45°.

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Parametric studies of mixed convective fluid flow around cylinders of different cross‐sections

Obalalu²,

Ibitoye

et al. 2023

Heat Trans

“…Some of the previous works done on mixed convective heat transfer are captured in various studies. [1][2][3][4][5][6] Olayemi et al 7 considered lid-driven convective flow in a square cavity exposed to different modes of heating and submitted that the maximum heat transfer took place close to the lower wall and the highest value of flow velocity occurrence at y = 0.4 in the vertical midplane at x = 0.5. Khan et al 8 analyzed lid-driven convective flow in a trapezoidal configuration housing a cylinder that was subjected to rotary motion.…”

Section: Introductionmentioning

confidence: 99%

Magnetoconvection around an elliptic cylinder placed in a lid‐driven square enclosure subjected to internal heat generation or absorption

Al‐Farhany

Obalalu³

et al. 2022

Heat Trans

The impacts of MHD and heat generation/absorption on lid‐driven convective fluid flow occasioned by a lid‐driven square enclosure housing an elliptic cylinder have been investigated numerically. The elliptic cylinder and the horizontal enclosure boundaries were insulated and the left vertical lid‐driven wall was experienced at a fixed hot temperature, and the right wall was exposed to a fixed cold temperature. COMSOL Multiphysics 5.6 software was used to resolve the nondimensional equations governing flow physics. A set of parameters, such as Hartmann number (0 ≤ italicHa ≤ 50 $0\le {Ha}\le 50$), Reynolds number (1 0 2 ≤ italicRe ≤ 1 0 3 $1{0}^{2}\le {Re}\le 1{0}^{3}$), Grashof number (1 0 2 ≤ italicGr ≤ 1 0 5 $1{0}^{2}\le {Gr}\le 1{0}^{5}$), heat generation‐absorption parameter (− 3 ≤ J ≤ 3 $-3\le J\le 3$), and elliptical cylinder aspect ratio (AR) (1.0 ≤ italicAR ≤ 3.0 $1.0\le {AR}\le 3.0$) have been investigated. The current study discovered that for low Reynolds number, the adiabatic cylinder AR of 2.0 provided the optimum heat transfer enhancement for the model investigated, also the impact of cylinder size diminishes beyond Gr = 104. But for high Reynolds (Re = 1000), the size of the cylinder with AR = 3.0 offered the highest heat transfer augmentation. The clockwise flow circulation reduces because of an increase in AR, which hinders the flow circulation. In addition, heat absorption supports heat transfer augmentation while heat generation can suppress heat transfer improvement.

“…However, with double-diffusive natural convection, increasing the Grashof number increases average Nu and the overall heat transfer rate [38]. The implications of Rayleigh number and geometric parameters on natural and mixed convective heat transfer in relevant enclosures were emphasized [39][40][41][42][43][44][45][46][47]. Salari et al [48] conducted a numerical study to determine the influence of turbulent transient models on natural convection in trapezoidal cavities.…”

Section: Introductionmentioning

confidence: 99%

Mixed Convective Heat Transfer in a Lid-Driven Concentric Trapezoidal Enclosure: Numerical Simulation

Al‐Farhany

Ibitoye

et al. 2022

JERA

This study investigates the implications of the area ratio (AR) and Grashof number (Gr) on fluid flow properties and heat transfer due to mixed convection around heated trapezoidal blocks located concentrically inside a larger trapezium driven by a lid. The outer trapezium's upper and lower horizontal walls are moving in opposite directions. The model developed was solved using the finite element technique. The inner walls of the trapezium are retained at an isothermal temperature, while the slanted outer walls of the trapezium are perfectly insulated. The upper and lower walls of the enclosure are subjected to normalized sinusoidal temperatures. Grashof number in the range of 103£Gr£105 and area ratios ( ) of , and were investigated. The simulation outcomes are displayed as stream function, isothermal contours, and local Nusselt number. Considering the interval of for the inner block, the Nusselt number increase with diminishing area ratio for the upper wall, while the response of the lower wall to Gr variation is a function of the AR considered. At the bottom wall of the outer trapezium, results showed that the rate of heat transfer was not significantly affected by changes in area ratio. Furthermore, as the AR reduces, the heat transmission along the top wall of the outer trapezium improves with the Grashof number, with the least and peak heat transfer enhancements occurring at 50 % and 100 % percent of the wall length, respectively.