Calculating Pressure Difference in Venturi Meter

[Bruce Dutton]

Homework Statement

The gauge pressure at the inlet of a horizontal venturi meter is 40kPa. The vacuum at the throat is 38 mm mercury. If a differential U-tube manometer containing mercury is the U-tube and the oil in the connecting tubes is connected to the venturi, what will the difference in the mercury levels be? the fluid in the venturi meter is oil with a relative density of 0.8.
Answer [0,359m]

Homework Equations

I am bit stuck i can get the pressures of the tubes but i am having problem trying to get the levels...

The Attempt at a Solution

 

[Q_Goest]

Hi bruce. Do you have a picture of this? That would help. It seems like all you need to do is determine the height of a column of fluid. Granted, this is complicate by what sounds like a column of mercury plus a column of oil, but the total pressure caused by two disimilar liquids is the sum of the pressure exerted by each liquid individually.

 

[Bruce Dutton]

I don't but what i can imagine is that the one side of the U tube would be at the opening of the venturi and the other side in the smaller tube of the venturi... well that's how i would picture it since it is dealing with different pressures... i would assume, Bruce