## flow rate and pressure

## flow rate and pressure

(OP)

I am an electrical engineer and have a question reagarding a hydraulic generator. The hydraulic system of this unit is tied into the rest of the hydraulic system so the flow to the generator varies quite a bit. There is a built in regulator for maintaining some nominal flow rate(8gpm). This regulator doesnt seem to work as described or is not very well made. So the generator will put out voltages as high as 190 volts when rotating at 4300rpm(frequency is arounf 70 Hz). My question is if we put in a ball valve to restrict the flow to some nominal (8gpm) then if the pressure of the system increases, will this increase the flow rate? What relationship is there between pressure and flow rate in a hydraulic system? I have submersible pumping experience(oil and water). I cant understand why this would not help maintain a more costant flow rate? Can anyone help. I was thinking the pressure of the system would only increase if a hydraulic load is turned off or something. Excuse my ignorance on hydraulic systems. Thanks to all in advance.

## RE: flow rate and pressure

## RE: flow rate and pressure

## RE: flow rate and pressure

Hopefully I am not over-simplifying things, but flowrate, Q, is simply determined by the product of density, rho, velocity, V, and area, A (Q = rho*V*A). With incompressible, subsonic flow (such as hydraulic oil), decreasing area increases velocity and decreases pressure. Conversely, increasing area decreases velocity and increases pressure. Hope this helps.

Haf

## RE: flow rate and pressure

## RE: flow rate and pressure