Calculating Static Pressure gain in expansion

[oaskar]

In doing the pressure drop calculations based on the expansion of the 8"D to a 10"D and also eliminating the 45 degree elbows, do i need to calculate the SP gain in expansion(if so is the Static Regain factor = old cross sectional area/new?) or is it unnecessary if I just know how much velocity(in fpm) I lost from the expansion?

Also after calculating the total pressure drop in the system, what other criteria do i look at to determine the efficiency of the system i designed??
Thank you!

 

[hydroMC117]

OK, if nobody else will admit it, I'll pipe up. Oaskar, I have no idea what you're talking (typing) about. Is this the lingo of pneumatic engineers? I'm a hydraulics guy and we rarely consider thermal expansion properties of the fluid medium. My concept of efficiency is useful power out vs total power input and it is typically hard to be precise since the largest inefficiencies manifest as heat-loss.