SALOME : impeller design

Salome : Free and Open source cad and meshing software. Today I tried using salome to model a impeller. The model was not an accurate design but an approximate to the actual one. Salome lacks a majot feature for blade designing i.e "loft". This was the only issue which I faced while creating the geometry.

Now let me explain you the steps in salome for making this design.

P.S. : The dimensions are in mm and other dimensions are just taken randomly.

Step 1.

In salome go to  " New Entities > 2D Sketch " and create a 2D image for the impeller as shown.

Step 2.

Click on the  " Reset Axis " to change the view of the sketch.

Create a face for the sketch using  " New Entity > Build > Face ".

Select the edges of the sketch and then click on Apply.

Step 3.

We need to revolve the face along an axis to complete the impeller design.

Go to " New Entity > Generation > Revolution ".

Click on the face and the axis along which we want to revolve and provide the input for revolution. In this case it is 360 deg.

Step 4.

Now we need to create the blades for the impeller.

Note that : The blades here are not having the perfectly aerofoil design shape as expected. The Salome seems to be lagging the lost function or may be I am not able to find it and hence its just an approximate design which I have come up with.

The thickness of the blade is 4mm and the top and bottom part of the blades are having a length of 58 mm and 80 mm.

To create the blade go to points and then create the points at the top surface of the impeller and at the bottom surface where the impeller blades cut the impeller.

Twist the bottom surface of the blade by and angle of 45 deg and having some curved surface.

STEP 5.

Similarly create a face for the blade and not extrude it along the Z axis.The blade has a thickness of 4 mm.

STEP 6.

To make multiple blades we need to create multiple copies of the blade. This can be done as follows :

Go to "Operation > Transformation > Multi-rotation"

Now create about 22 such copies of the blade with an angle of 25 deg in between each blade.

Now to make the geometry as a single model fuse the impeller and the blade using the fuse option. (" Operation > Boolean > Fuse ")

Save the mesh as impeller.msh (save it in ascii format)

This completes our geometry although not exact, but still an effort to create a impeller blade. I hope the loft option gets updated in the new release of Salome.( I am currently using Salome 7.2.0)

Meshing might take a while....so stay updated.. :)