Defining Physics and Conditions

The physics and conditions are specified as follows.

Click Select Modules in the Model Panel. The Physical Model Selection dialog box opens.
Circumferential Valve is automatically added to the Model Panel by the Valve Template Mesher.
Select Turbulence, Heat and Rotation (1 DOF) under Available Modules and click Add.
Click Close to close the Physical Model Selection dialog box.

Figure 6.581 - Adding modules

Select Circumferential Valve in the Model Panel.
Select Rotation (1 DOF) from the Dynamics drop-down list in the Model Tab of Properties Panel, to link the motion of the Circumferential Valve to the Rotation (1 DOF) module.
Enter the parameters for the Valve Configuration as follows.
- Minimum Gap Size: 1e-05
- Maximum Displacement: 0.005

Figure 6.582 - Circumferential valve-Operating parameters

Note:

Closure Model determines whether the flow is fully blocked at the Minimum Gap Size.
The Minimum Gap Size specified in the Valve Template Mesher is larger than that for the actual model, so that the domain has a reasonable cell count.

Select Rotation (1 DOF) in the Model Panel.
Enter the Time Definition parameters in the Model Tab of Properties Panel.
- Number of Cycles: 10
- Number of Time Steps per Cycle: 100
Select Force Balance from the Motion Type drop-down list
Enter the parameters for Motion Type as follows.
- Moment of Inertia: 2e-06
- Torsion Constant: 2
- Torsion Preload Torque: 0.002
- Rotational Axis Vector: 0, 0, 1
- Center of Rotation: -0.0181899, 0.022586, 0

´	Note: Number of Time Steps per Cycle is an important parameter and needs to be large enough to achieve a smooth solution.

Figure 6.583 - Rotation 1 (DOF) - Operating parameters

The boundary conditions are preset by the Valve Template Mesher and are specified as follows:

Select the entities under Boundaries from the Geometric Entities Panel, as shown inTable 6.32.
In the Model Tab of Properties Panel, verify the boundary type for the Circumferential Valve drop-down list, as shown in Table 6.32.

Boundaries	Circumferential Boundary Type
valve_bot, valve_cylinder_in, valve_cylinder_out, and valve_top	Cylinder
valve_end	Valve End
valve_mgi_inlet	Valve End
valve_valve	Valve

Table 6.32 - Boundary type

Select inlet_inlet from the Boundaries list in the Geometric Entities Panel.
Select Inlet from Circumferential Valve drop-down list in the Model Tab of Properties Panel.
Click Edit Expression icon in the Inlet Pressure to open the Expression Editor dialog box .
Copy and paste the expressions written under Description drop-down list for Global Expressions, see Figure 6.584

Figure 6.584 - Inlet conditions

Select outlet_outlet from the Boundaries list in the Geometric Entities Panel.
Select Outlet from the Circumferential Valve drop-down list in the Model Tab of Properties Panel.
Enter Outlet Pressure as 101325 Pa.

Figure 6.585 - Outlet conditions

Enter the parameters for Operating Conditions as follows.

Figure 6.586 - Fluid properties