ME 333 Fluid Mechanics

Recitation 2

1. Pressure gage B is to measure the pressure at point A in a water flow. If the pressure at B is 87 kPa, estimate the pressure at A (in kPa). Assume all fluids are at 20°C.

2. An inclined-tube reservoir manometer is constructed as shown. Derive a general expression for the liquid deflection, L, in the inclined tube, due to the applied pressure difference, ∆p.

3. The circular gate ABC has a 1m radius and is hinged at B. Compute the force P just sufficient to keep the gate from opening when h = 8 m . Neglect atmospheric pressure.

4. The gate in the figure is 1.5m wide and is hinged at point B which rests against a smooth wall at a point A. Compute (a) the force on the gate due to seawater pressure. (b) the horizontal force P exerted by the wall at point A, and (c) the reactions at the hinge B.

5. A dam has a parabolic shape z/z0=(x/x0)2 as shown below, with x0=10 ft and z0=24 ft. The fluid is water, γ=62.4 lbf/ft3, and atmospheric pressure may be omitted. Compute the forces FH and FV and the dam. The width of the dam is 50 ft.

6. A crane is used to lower weights into the sea (density = 1025 kg/m3) for an underwater construction projects. Determine the tension in the rope of the crane due to a rectangular 0.4 m ⋅ 0.4 m ⋅ 3 m concrete block ( density = 2300 kg/m3) when it is (a) suspended in the air and (b) completely immersed in the water.