Computational Fluid Mechanics (CFM)
S. Rasoolzadeh; M. Y. Hashemi
Abstract
The purpose of this paper is to numerically simulate unsteady, incompressible, and laminar flow with natural and mixed convection heat transfer in a square lid-driven cavity filled with Cu-Water nanofluid. Jameson method is used in conjunction with the Artificial compressibility method on the unstructured ...
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The purpose of this paper is to numerically simulate unsteady, incompressible, and laminar flow with natural and mixed convection heat transfer in a square lid-driven cavity filled with Cu-Water nanofluid. Jameson method is used in conjunction with the Artificial compressibility method on the unstructured grid in a viscous flow. Effects of Grashof number and nanoparticle volume fraction on the flow and heat transfer characteristics are investigated. Two-dimensional Navier-Stokes equations as the governing equations of the problem are discretized with the finite volume method. Spatial discretization is performed with a two-order central scheme; and Jameson artificial dissipation terms are added to equations to stabilize the solution. Unsteady terms are discretized with an implicit two-order scheme and are solved with fourth-order explicit Runge-Kutta method in pseudo-time. It is found that the Jameson method has good performance with a reasonable convergence rate. Results show that an increase in the volume fraction of nanoparticles improves heat transfer characteristics while the increase in the Grashof number, weakens the heat transfer due to the domination of natural convection.
Computational Fluid Dynamics (CFD)
Tohid Adibi
Abstract
In this paper the characteristics of unsteady three-dimensional incompressible flows with heat transfer are obtained along with artificial compressibility of Chorin. At first, compatibility equations and pseudo characteristics for three-dimensional flows are derived from five governing equations (continuity ...
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In this paper the characteristics of unsteady three-dimensional incompressible flows with heat transfer are obtained along with artificial compressibility of Chorin. At first, compatibility equations and pseudo characteristics for three-dimensional flows are derived from five governing equations (continuity equation, Momentum equations in three directions, and energy equation) and then results are simplified to two dimensional flows. Pseudo Mach hyper-cone (four dimensional cone) are found and its cross-section with physical axis is calculated numerically. Unlike compressible flow, this is not a sphere. It is found that the pseudo acoustic speed within the incompressible flow is function of artificial compressibility parameter and the directions. In two dimensional, Pseudo Mach cone is obtained by numerical solution of characteristic equations. Unlike compressible flow, the cross section of Mach cone with x-y plane is not circle. This shape is not oval, too. The influence of artificial compressibility parameter on convergence history and accuracy was surveyed by simulation of cavity flow as a benchmark
