Simulation of the turbulent flow in a 3D channel and over a surface mounted cube Youngwook Kang, Cornell University Andrei Simion, The Cooper Union Svetlana V. Poroseva, CSIT, Florida State University

Objectives To become proficient in using Fluent and Gambit To get experience in: acquiring numerical solutions of PDE solving a CFD problem

Problem Description Study on the influence of different side wall boundary conditions on flow characteristics in a 3D geometry. - Flow types 1. Flow in a rectangular channel 2. Flow over a surface mounted cube - Boundary Conditions 1. Periodic 2. Solid

Flow Geometry Channel Geometry: 2h in height, 2h in flow direction, and 3h in spanwise direction. (h=0.025m) Channel with surface mounted cube: Fluid: air Data from Hussain and Marinuzzi’s experiment (1996) was used.

Turbulence Models

Numerical Procedure - 2nd order spatial discretization scheme - Segregated, implicit solver - Steady flow - Boundary Conditions 1. Walls in z direction 2. Walls/Periodic in x direction 3. Channel: Periodic inlet/outlet 4. Cube: Fully developed channel flow (inlet) and convective outlet

Grid - Structured non-uniform with clustering near walls - With such grid resolution, wall description with wall functions; focus on mean velocity profiles. Channel (x:z) 47:41 Cube (x:z:y) 47:41:86

Channel Plots

Channel Plots (cont.)

Surface Mounted Cube Plots

Surface Mounted Cube Plots (cont.)

Surface Mounted Cube Plots (cont.)

Contours

Contours (cont.)

Results and Conclusion We have learned how to use Fluent and Gambit to design simple meshes and solve CFD problems in application to turbulence modeling. Different boundary conditions on side walls have a great influence on the flow characteristics, such as velocity, vorticity, and turbulent kinetic energy.