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September 20, 2015, 13:40
#1
New Member

Suraj Kashyap
Join Date: Sep 2015
Posts: 5
Rep Power: 9
Hi,
I am doing some reverse engineering on a centrifugal impeller (shrouded, image attached). To generate the geometry for meshing, I am using Bladegen, but I ran into a couple problems.
1. In the Initial Angle/Thickness Dialog box (image attached), what is the angle asked for? Is it the wrap angle or the vane inlet angle (beta). If it is the wrap angle, is it the one at the hub or that at the shroud as that is different in my case?
2. I have attached an image of the projection of the blade curve on the hub floor (image attached). Since the blade has considerable thickness, I am confused as how to measure the wrap angle. A and B are points on the vane inlet and exit on the pressure side and C and F are those on the suction side. B and E are the median points. Which points should I take to find out the wrap angle?

Attached Images
 Bladegen_Dialog_Box.JPG (34.8 KB, 73 views) Vane_Curve_Projection.JPG (60.0 KB, 65 views) Impeller_Sectional_View.JPG (48.6 KB, 70 views)
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 April 5, 2019, 13:24 #2 New Member   Subodh Ranjan Join Date: Mar 2018 Posts: 8 Rep Power: 7 Hi there! A bit off-topic, could you tell me how to determine the wrap angle. I have calculated the basic impeller dimensions, ie, 1. Meridional velocities at impeller inlet and exit 2. The diameter of the impeller at the inlet and exit 3. The diameter of the hub at the inlet 4. Inlet vane angle 5. Outlet vane angle 6. RPM and hence the peripheral velocities at the inlet and outlet How do I calculate the wrap angle now? I'm using BladeGen to generate the impeller but I cannot accurate do it unless I have this

 Tags bladegen, centrifugal impeller, theta, turbogrid, wrap angle