SCHOOL of ENGINEERING               UNIVERSITY of PLYMOUTH                                   

 

BENG1   INTRODUCTION to THERMO-FLUIDS  (THER 103)

 

TUTORIAL EXAMPLES in FLUID STATICS

 

Assume: rwater = 103 kg/m3;  rmercury = 13.6 x 103 kg/m3;  rair = 1.2 kg/m3

 

SSL conditions are 101.325 kPa, and 15°C

 

 

1.                  A U-tube manometer is used to measure the pressure difference due to water flow between two tapping positions on the inclined pipe as shown in Figure Q1.
If the manometer reading ‘h’ is 65 mm, calculate the pressure difference ( p1 – p2 ) in kPa.                           [10 kPa]


 

 

 

 

 

 

Fig. Q1

 

 

 

2.                  A vertical-sided fish tank with sides measuring 1m width by 0.6m depth is filled with fresh water to a height 50mm below the top edge. Determine the net pressure force and centre of pressure on the vertical side.        [1484 N; 0.3667 m from surface]

 

3.                  A viewing port at an aquarium is square in shape and orientated 35° to the vertical. The top edge is 3.4 meters below the surface of the water. If the viewing port measures 1m square find the net force acting on it and the moment about the top edge. Assume the water density is 1028 kg/m³.          [38.418 kN; 26.094 kNm]

 

4.                  A circular plate is used as a flood control device at the exit of a 300mm diameter pipe. The plate is angled at 15° clockwise from vertical and the centre of the plate is 5.2 m below the water surface. Find the net moment about the top of the plate needed to maintain it in the closed position.                                       [3,606 N; 544.7 Nm]