Fluid Statics

Example 2 :

A two liquid double column enlarged-ends manometer is used to measure pressure difference between two points. The basins are partially filled with liquid of specific gravity 0.75 and the lower portion of U-tube is filled with mercury of specific gravity 13.6. The diameter of the basin is 20 times higher than that of the U-tube. Find the pressure difference if the U-tube reading is 25 mm and the liquid in the pipe has a specific weight of 0.475 N/m3.

Solution :

Given data: U-tube reading 25 mm
                   Specific gravity of liquid in the basin 0.75
                   Specific gravity of Mercury in the U-tube13.6
                   As the volume displaced is constant we have,

                          

 
[a, A -- X-Section of tube and basin respectively]
Fig. Ex 2

Equating pressure head at (A--A)

Put the value of Y while X and Z cancel out.
Answer: 31.51 kPa

Prev
First | Next | End