Does anyone have experience using a positive displacement pump? I found a tri-clover, lobe-based PD pump that I'm thinking about purchasing and I think I have an understanding of them, but if anyone can provide practical input or check my knowledge, that would be awesome. It's my understanding that rotary pumps are better at handling air pockets as they provide suction rather than just accelerating the fluid. Any disadvantages in this application, other than the overall complexity/maintenance?
Fluid flow...since they pump at a fixed rate, restricting output would create a mounting pressure, so the common March pump method isn't applicable here. And thanks to to Wikipedia's For Dummies section on NPSH, despite enjoying some beer at the moment, I think I understand why you can't restrict the input (lower pressure that makes fluid flow ineffective). So my conclusion is that, for the practical purpose of including this pump in a brewery, it's fairly difficult to control flow rate, or are there any other methods?
Fluid flow...since they pump at a fixed rate, restricting output would create a mounting pressure, so the common March pump method isn't applicable here. And thanks to to Wikipedia's For Dummies section on NPSH, despite enjoying some beer at the moment, I think I understand why you can't restrict the input (lower pressure that makes fluid flow ineffective). So my conclusion is that, for the practical purpose of including this pump in a brewery, it's fairly difficult to control flow rate, or are there any other methods?