Presentation on theme: "Pharos University ME 259 Fluid Mechanics for Electrical Students Revision for Mid-Term Exam Dr. A. Shibl."— Presentation transcript:
1 Pharos University ME 259 Fluid Mechanics for Electrical Students Revision for Mid-Term Exam Dr. A. Shibl
2 Manometer Example Solution: Determine the pressure at point A in the figure below if h1 = 0.2 m and h2 = 0.3 m. Use water = 1000 kg/m3.Solution:P2 = P1 + Hggh2But P1 = Patm (open to atmosphere) ==>P1 = 0 (gauge) P2 = Hggh2P3 = PA + waterg(h1+h2)We know that P2 = P3 (same horizontal level)ThusHggh2 = PA + waterg(h1+h2)PA = Hggh2 - waterg(h1+h2)PA = 13.54x1000x9.81x0.3 – 1000x9.81x( )PA = 39,PA = 34.9 kPa (gauge)Points to be selected:1 – at the open end of the manometer2 – at the right leg of the manometer3 – same level with point 2 but at left leg of the manometer4 – same level as point APressure at the points:P1=PatmP2 = P3P4 = PA
3 Static Force ExampleA rectangular gate of dimension 1 m by 4 m is held in place by a stop block at B. This block exerts a horizontal force of 40 kN and a vertical force of 0 kN. The gate is pin-connected at A, and the weight of the gate is 2 kN. Find the depth h of the water.
5 Continuity ExampleWater flows steadily through a nozzle. The nozzle diameter at the inlet is 5 cm, and the diameter at the exit is 3cm. The average velocity at the inlet is 4 m/s. What is the average velocity at the exit?V1 A1 = V2 A2
7 Water moving through Venture nozzle reaches a low pressure at section 1. Nozzle dimensions are d1 = 3 mm, d2 = 9 mm, and h = 150 mm. Determine the minimum possible water speed (V2) at the exit of the nozzle so that fluid will be drawn up the suction tube.
8 Momentum Equation For Steady Flow ΣFx= ṁ (V2—V1)x
9 A water jet with a velocity of 30 m/s impacts on a splitter plate so that 1/4 of the water is deflected toward the bottom and 3/4 toward the top. The angle of the plate is 45o. Find the force required to hold the plate stationary. Neglect the weight of the plate and water, and neglect friction.