Vacuum Calculation

[Bambila]

Hi,

I have attached a snap of the Vacuum system. can anyone please help me to find the Vacuum need to create in the chamber so that fluid from the reservoir suck into the Chamber?

Regards,
Bambila

Bambila
Mechanical Engineer

 

[PEDARRIN2]

feet of lift/suction = psi x 2.31 / (specific gravity)

You will have to convert to your units.

 

[LittleInch]

I thought this looked like homework, but your profile doesn't look like that so I'll give you the benefit of the doubt.

The liquid needs to rise 0.55m assuming your reservoir level doesn't change. Therefore the pressure in bar required to lift this is m x sg /g. As this is negative from atmospheric the pressure in the chamber needs to be 1 barg- (0.55 x SG /9.81).

Still looks like homework though....

My motto: Learn something new every day

Also: There's usually a good reason why everyone does it that way

 

[Bambila]

Thanks for the replay.

Can you please explain how this equations are derived or provide me any reference material?

Bambila
Mechanical Engineer

 

[LittleInch]

Basic physical equations. Look up "conversion of head to pressure" and that should give you the basics you need.

Isaac Newton came up with the basic equations....

My motto: Learn something new every day

Also: There's usually a good reason why everyone does it that way

 

[PEDARRIN2]

A column of water 2.31 feet high will exert a pressure of one (1) psi based on water at approximately 65 F. Since specific gravity uses water as the basis (value of 1), inputing the specific gravity of the fluid in question into the equation will provide the pressure required/supplied to move a column of fluid up or down.

I got this out of Cameron Hydraulic Data, but any reference on basic fluid flow should have it.