Fan in Room

Download mesh

Download simulation

Introduction

This is an example of a simulation using a sliding mesh.

It is a simple problem with a fan rotating at 100 RPM in a room with air flowing through a window.

The simulation conditions are as follows

  • solver : buoyantSimpleNFoam
  • turbulence model : $Standard$ $k-epsilon$
  • rotating velocity : 100 RPM

Start BaramFlow and load mesh

Start BaramFlow

Run the program and select [New Case] from the launcher. In the launcher, select [Pressure-based] for [Solver Type] and [None] for [Multiphase Model].

Mesh

Use the given polyMesh folder. In the top tab, click [File]-[Load Mesh]-[OpenFOAM] in that order and select the polyMesh folder.

General

For this example, we’ll use default conditions.

Models

For this example, we’ll use default conditions.

Materials

Material properties of air is as follows

Boundary Conditions

Set the boundary type and values as shown below.

  • desk_surface, door_surface, room : Wall – No Slip
  • fan_surface : Wall – Moving Wall-Mesh Motion
  • outlet : Pressure Outlet – Total Pressure = 0

  • Cylinder_1_surface, Cylinder_1_surface_slave : interface – Internal Interface

Once all settings are complete, it will appear as shown in the figure below.

Dynamic Mesh

Select Moving Cell Zone in Motion Type.

Click Add Motion at the bottom.

Click Add Motion Function and select Rotating. Set Origin, Axis Speed as below

  • Origin : (-3 2 2.6)
  • Axis : (0 0 1)
  • Speed : 100 (RPM)

Select cellZone at CellZones.

Numerical Conditions

In this example, we’ll change the settings as shown below.

  • Pressure-Velocity Coupling Scheme : SIMPLE
  • Use Momentum Predictor : On
  • Discretization Schemes
    • Time : First Order Implicit
    • Pressure : Linear
    • Momentum : Second Order Upwind
    • Turbulence : First Order Upwind
  • Under-Relaxation Factors : 1 for all
  • Max Iteration per Time Step : 1
  • Number of Correctors : 4

Initialization

For this example, we’ll use default values.

Enter the value and click the Initialize button at the bottom. Then click the [File]-[Save] menu to save the case file.

Run

Change the values as shown below, and click [Start Calculation] button.

  • Time Stepping Method : Adaptive
  • Couraant Number : 1
  • EndTime : 1
  • Save Interval : 0.02
Residual plot