## 7.7. Creating a New Volute

You can create a system that contains the volute geometry and volute mesh from the pump you have designed in Vista CPD using the Create New > Volute command in the right-click context menu of an up-to-date Blade Design cell. The geometry cell contains a parametric volute geometry model, the parameters of which may be modified after creation, similar to a regular DesignModeler parametric model. The mesh cell contains a tetrahedral mesh which includes inflation layers on the volute walls. This mesh is ready for combining with the matching impeller mesh for CFD analysis.

The volute parameters are as follows:

- r3, volute inlet radius

- b3, volute inlet width

- b2, impeller tip width

- clear, the clearance between the impeller and the volute tongue

- thk, the volute tongue thickness

- theta2, the angle of inclination of volute inlet to the horizontal.

  An angle of zero gives a regular cylindrical inlet, whereas a non zero angle results in a conical inlet section. This is the same as the impeller trailing edge angle of inclination.

- thetaCR, the volute casing rotation angle

- Elliptical/circular volute only: minor1 to minor8, the ellipse cross section minor axis

- Rectangular volute only: height1 to height8, the rectangular cross sectional height

- Rectangular volute only: aspectRatio, the aspect ratio of the throat cross section

- diffLength, the axial length of the volute diffuser section

- diffDiam, the exit diameter of the volute diffuser section

Release 18.2 - © ANSYS, Inc. All rights reserved.