# U TUBE MANOMETER CALCULATOR U-tube manometer calculator to find the gage pressure pA relative to the atmosphere. The chamber fluid ρ1 is separated from the atmosphere by a second fluid ρ2.The equation of gage pressure pA can be written as

pA(Gage) = ρ2gh2 - ρ1gh1 or (pA(Gage) = γ2h2 - γ1h1)

pA(Abs) = ρ2h2 - ρ1h1 +patm or (pA(Abs) = γ2h2 - γ1h1 +patm)

The fluid in A in can be either a liquid or a gas. If A does contain a gas, the contribution of the gas column γ1h1, is almost always negligible so that , and in this instance equation becomes

pA(Gage) = ρ2h2 or (pA(Gage) = γ2h2)

pA(Abs) = ρ2h2+patm or (pA(Abs) = γ2h2+patm)

 KNOWN PARAMETERS Density[ρ], Gravity [g] Specific Weight [γ] INPUT PARAMETERS Density[ρ1] kg/m^3 slugs/ft^3 lbm/ft3 Density[ρ2] Specific Weight [γ1] N/m^3 lb/ft^3 Specific Weight [γ2] Gravity [g] m/s^2 ft/s^2 Depth [h1] mm m in ft Depth [h2] Atmosphere Pressure [patm] (Free Surface Pressure) Pa bar psi kPa

Note: If fluid 2 is below point 3, then enter negative height values for h2

Note: Use dot "." as decimal separator.

 RESULTS Pressure A Gage [pA(Gage)] bar Pressure A Absolute [pA(Abs)]

### Reference:

• Munson, B. R., Young, D. F., & Okiishi, T. H. (2016). Fundamentals of Fluid Mechanics, 8th Edition . Hoboken, NJ: J. Wiley & Sons.