Influence of the chamber inclination angle and heat-generating element location on thermal convection of power-law medium in a chamber

Abstract

Purpose This paper aims to study the mathematical modeling of passive cooling systems for electronic devices. Improving heat transfer is facilitated by the correct choice of the working fluid and the geometric configuration of the engineering cavity; therefore, this work is devoted to the analysis of the influence of the position of the heat-generating element and the tilted angle of the electronic cabinet on the thermal convection of a non-Newtonian fluid. Design/methodology/approach The area of interest is a square cavity with two cold vertical walls, while the horizontal boundaries are adiabatic. An element of constant volumetric heat generation is placed on the lower wall of the chamber. The problem is described by Navier–Stokes partial differential equations using dimensionless stream function and vorticity. The numerical solution is based on the developed computational code using the finite difference technique and a uniform rectangular grid. Findings The key conclusions of this work are the results of a detailed analysis of streamlines and isotherms, the average Nusselt number and profiles of the average heater temperature. It was found that more intensive cooling of the heat-generating element occurs when the cavity is filled with a pseudoplastic fluid (n < 1) and not inclined (α = 0). The Rayleigh number of Ra = 105 and the thermal conductivity ratio of k = 100 are characterized by the most positive effect. Originality/value The originality of the research lies in both the study of thermal convection in a square chamber filled with power-law fluid under the influence of a volumetric heat production element and the analysis of the influence of geometric and thermophysical parameters characterizing the considered process.

Natural convection cooling process from two identical porous‐covering electronic components

“…In addition, the difference between the experimental results and those obtained by numerical simulation is less than 5%. Loenko et al 15 investigated numerically the position effect of a heat-generated local element, simulating an electronic device, inside a closed cavity filled with a non-Newtonian fluid for different inclination angles of the cavity. Their results indicated that minimum average heat generating element temperature is obtained when the cavity is not inclined and for the case with a pseudo-plastic working fluid (n < 1).…”

Cooling of a periodic heat-generating solid element in an electronic cabinet using a non-Newtonian pseudoplastic nanofluid and a heat-conducting substrate

“…To approximate and solve the described system of nonstationary differential equations ( 1)-( 5), various schemes based on the finite difference procedure have been used (Loenko et al, 2021a(Loenko et al, , 2021b. The method of successive over relaxation has been applied to solve the approximated Poisson equation ( 1).…”

Buoyancy‐motivated dissipative free convection flow of Walters‐B fluid along a stretching sheet under the Soret effect and Lorentz force influence

“…Their analysis revealed that enhancing thermal radiation upsurges the energy profile adjacent to the stretching sheet. However, the detailed study on flow and thermal behavior of non-Newtonian fluids is in References [5,6,[28][29][30][31][32][33][34][35][36].…”

“…On the other hand, in non‐Newtonian fluids, viscosity varies with their strain rate, owing to this reason these fluids do not have fixed or constant viscosity. Grease, cheese, lava, liquid soaps, paints, cosmetics, petroleum, mayonnaise, saliva, blood, jam, soup, butter, toothpastes, magma, synovial fluid, and many others are examples of non‐Newtonian fluids 4–6 . However, Walters‐B fluid, Powell–Eyring fluid, Casson fluid, Jeffrey fluid, Maxwell fluid, Williamson fluid, and micropolar fluids are very important non‐Newtonian fluids due to their significant industrial applications.…”