Centrifugal Pump Impeller leading edge angle

[mikehadjipa]

Hi, i am working on the design of a water pump. Basically the dimensions of the casing are fixed and so are Q and P and r1 and r2. I need to determine inlet and outlet blade height(b1, b2), number of blades and the leading and trailing edge angles(beta 1, beta 2). With the formulas given to me the angles (beta1, beta2) are only funtions of the blade heights(b1, b2) so i only need to determine b1, b2 and n. I followed an iterative procedure and i have determined outlet Blade heigh (b2) and trailing edge angle (beta 2) and number of blades based on the outflow disalignment.
I want help on how to determine inlet blade height (b1) and leading edge anle (beta 1). I have read a lot in this forum about pumps but i still dont get this one.
If i follow Stepanoff approach and design beta 1 in a range of 5 degrees from beta 2 will this a good approach or do i have to design beta 1 as close to 22.5 for best efficiency (as read in an article).
Thank you

 

[BigInch]

When in doubt, stick with Stepanoff.

BigInch-born in the trenches.

http://virtualpipeline.spaces.msn.com