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MEE20003 Fluid Mechanics 1 Tutorial 5 1. A water jet of diameter 30 mm and speed v = 25 m/s is filling a tank. The tank has a mass of 25 kg and contains 25 liters of water at the instant shown. The water temperature is 15oC. Find the force acting on the bottom of the tank and the force acting on the stop block. Neglect friction. 󰇟:  150.9;   905󰇠

Problem 1 2. A horizontal water jet at 21oC issues from a circular orifice in a large tank. The jet strikes a vertical plate that is normal to the axis of the jet. A force of 2.7 kN is needed to hold the plate in place against the action of the jet. If the pressure in the tank is 170 kPa gage at point A, what is the diameter of the jet just downstream of the orifice? 󰇟:  0.1󰇠

Problem 2 3. Determine the external reactions in the x- and y-directions needed to hold this fixed vane, which turns the oil jet (S = 0.9) in a horizontal plane. Here V1 = 21 m/s, V2 = 19.8 m/s, and Q = 0.043 m3/s. 󰇟:  1476󰇛󰇜;  383󰇛󰇜󰇠

Problem 3

4. A cone that is held stable by a wire is free to move in the vertical direction and has a jet of water (at 10oC) striking it from below. The cone weighs 30 N. The initial speed of the jet as it comes from the orifice is 15 m/s, and the initial jet diameter is 2 cm. Find the height to which the cone will rise and remain stationary. Note: The wire is only for stability and should not enter into your calculations. 󰇟:   3.21󰇠

Problem 4 5. Water at 15oC flows through a nozzle that contracts from a diameter of 10 cm to 2 cm. The exit speed is v2 = 25 m/s, and atmospheric pressure prevails at the exit of the jet. Calculate the pressure at section 1 and the force required to hold the nozzle stationary. Neglect weight. 󰇟:  312;   2.26󰇠

Problem 5 6. This spray head discharges water (ρ = 1000 kg/m3) at a rate of 0.12 m3/s. Assuming irrotational flow and an efflux speed of 20 m/s in the free jet, determine what force acting through the bolts of the flange is needed to keep the spray head on the 15 cm pipe. Neglect gravitational forces. 󰇟:   5140󰇠

Problem 6

7. This bend discharges water (ρ = 1000 kg/m3) into the atmosphere. Determine the force components at the flange required to hold the bend in place. The bend lies in a horizontal plane. Assume viscous forces are negligible. The interior volume of the bend is 0.25 m3, D1 = 60 cm, D2 = 30 cm, and V2 = 10 m/s. The mass of the bend material is 250 kg. 󰇟:  󰇛18.6  6.12  4.91󰇜󰇠

Problem 7 8. A pipe 0.3 m in diameter bends through an angle of 135o. The velocity of flow of gasoline (S = 0.8) is 6 m/s, and the pressure is 70 kPa gage in the bend. What external force is required to hold the bend against the action of the gasoline? Neglect the gravitational force. 󰇟:   󰇛11,917  4936󰇜󰇠...