Dilemma to determine the absolute pressure or gauge pressure? 1

[knapee]

Dear Sir

The fan blower veneer to me the acceleration head V^2/2g * density is gauge pressure, so I have to add 1 atm to get the vapor density through PM/RT equation.

But, from Bernoulli equation, P1/(density*g) + H1 + V1^2/(2g) = P2/(density*g) + H2 + V2^2/(2g), the term P1 should be absolute pressure so the V1^2/(2g) must be absolute pressure. Am I right?

Besides that, P=density*g*h is absolute pressure or gauge pressure?


Thank you very much.

 

[zdas04]

A closed form equataion (as opposed to an empirical) equation like the Bernoulli Equation will always be in absolute units.

David