Hello, I'm a 3d designer who occasionally gets involved in the engineering side of things. Despite having no experience of pump design I find myself in the position of having to design one. I have found a windscreen washer pump (small high speed dc motor, 3 blade 22mmD propellor, 3.5mm outlet - I believe it's a vane pump) which does the job and I need to design a pump which will achieve a similar performance. A bad way to go about this would be to produce an inefficient pump and scale it up to achieve the flow rate I require. In order to produce a relatively efficient design I need to know how the following alter efficiency:
Distance between blade tips and housing
No of paddles
Flat or flared blades (looking down inlet)
Tapered blades (looking down outlet)
Is it better to have the outlet dividing wall sharp or rounded.
I also require some guidance/ rules of thumb on designing a tubular lead in to the blades- does a bad design cause cavitation- some pumps don't have this feature.
Apologies for my lack of pump terminology. Any help or direction will be greatly appreciated