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Physics Set-Up

Create New Material

In the problem specification, a density and viscosity are defined for the fluid flow that do not match those of the material sample of air. A new material must be defined with the properties that we wish to have. Select Material Assignments and, in the Material drop down menu, choose Create New. In the gas properties window, using the Add drop down menu, select Density and Viscosity. Input the values given in the problem specification for the appropriate properties.

Boundary Conditions / Forces

First, the inlet must be defined using the Fluid Flow Conditions. In the Add drop down menu by Fluid Flow Conditions, select Inletthen .Then, using the face selection tool, define the inlet as the plane perpendicular to the top step. Make sure to input the velocity magnitude as 0.4 m/s.

Once the inlet is defined, the outlet is next. In the same drop down menu, use the outlet tool to define an outlet Outlet at the end of the step. Assign a Gauge Static Pressurestatic pressure of 0 psi.

Create openings an opening for the sides top of the flow volume by selecting Opening in the Add drop down menu. Select the top face of the flow volume and input 0 Pa for the Gauge entrainment pressure.

Add a symmetry Symmetry condition from the Add drop down menu to the sides of the flow volume. Do not select the faces at the beginning and end of the steps.

Next, a wall Wall condition must be added to all surfaces that are not already defined. Wall can be found in the same Add menu as the previous conditions. In this demonstration AIM will automatically create the walls once the option is selected, ; AIM selects every face that doesn't already have a boundary condition  on on it.

 
Go to Step 5: Results

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