Calculating cfm for liquid aluminum
I'm trying to calculate cfm for melted aluminum passing through a venturi nozzle at 90 psi.
I can eventually determine the dimensions of the nozzle to get those necessary figures for the existing calculator. However, I am missing some things and ignorant of others.
Here's what I can determine on my own (TBD), what I know, and what I am completely clueless about:
upstream diameter Da- TBD
Diameter of the venturi neck Db- TBD
Pressure difference measured by Venturi Dp- ummm..what? And what's a Pa?
Fluid Density r- (avg) 2600 kg/m^3
Discharge Coefficient C- how?...what?
Upstream Pressure Tap- Pa ????????
Downstream Pressure Tap Pb?????
I also don't understand what that little p is or the weird u (unless it's the expected value from statistics) represent in some of the equations. ANY help would be greatly appreciated.