Presentation on theme: "Pharos University ME 259 Fluid Mechanics for Electrical Students Revision for Mid-Term Exam Dr. A. Shibl."— Presentation transcript:
1Pharos University ME 259 Fluid Mechanics for Electrical Students Revision for Mid-Term Exam Dr. A. Shibl
2Manometer 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
3Static 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.
5Continuity 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
7Water 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.
8Momentum Equation For Steady Flow ΣFx= ṁ (V2—V1)x
9A 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.