2. (a) How do you classify water turbines? (b) Define and explain different efficiencies of a water turbine. [8+8]

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1 Code No: RR Set No. 1 III B.Tech I Semester Supplementary Examinations, February 2007 HYDRAULIC MACHINERY AND SYSTEMS ( Common to Mechanical Engineering and Automobile Engineering) Time: 3 hours Max Marks: 80 Answer any FIVE Questions All Questions carry equal marks 1. (a) Draw typical velocity triangles for fluid motion along a series of moving curved vanes and explain the salient features. (b) A jet of water having a velocity of 30 m/s strikes a curved vane which is moving with a velocity of 15 m/s. The jet makes an angle of 30 0 with the direction of motion of vane at inlet and leaves at an angle of to the direction of motion of vane at outlet. Calculate vane angles if the water enters and leaves the vane with out shock and work done per second per unit weight of water striking the vanes per second. [6+10] 2. (a) How do you classify water turbines? (b) Define and explain different efficiencies of a water turbine. [8+8] 3. A hydroelectric power station requires a turbine producing 3MW at 250 rpm under a head of 25m. Calculate the specific speed of the turbine. Estimate the runner diameter if the speed ratio is 0.70 and suggest the type of the turbine and runner. 4. (a) Show from first principle, the work saved against friction in the delivery pipe of a double-acting reciprocating pump by fitting air vessel is 39.2% (b) A double acting reciprocating pump running at 60 r.p.m has a plunger diameter of 250 mm and a stroke of 500 mm. The delivery pipe is 100mm diameter and 50m long. If the motion of the pump is simple harmonic, find the power required to overcome friction of delivery pipe when a large air vessel is fitted at the center line of the pump. Assume f=0.01. [8+8] 5. (a) Draw the out let velocity triangle for forward curved vane of a centrifugal pump. (b) How does the pressure at the eye of a centrifugal pump vary with the fluid in contact with the impeller? What are the limitations on suction head [8+8]. 6. (a) What are the common problems associated with the working of a centrifugal pump? What are their remedial measures? (b) What are the similarity laws? What is the significance of each law? [8+8] 7. (a) Describe the principle of operation of a hydraulic ram and discuss limitations of this device in relation to head and discharge. [16] 1 of 2

2 Code No: RR Set No. 1 (b) Forty h.p are required to be supplied to the ram of a press from an accumulator through a 15 cm diameter pipe 1000m long. If the loss in transmission is to be 2.5 per cent, find the area of the press ram which is loaded with 100 tons. Take Darcy?s f for pipe as [8+8] 8. (a) A pipe 7.5 cm in diameter and 250 m long has a nozzle fitted at the discharge end. The total head at the inlet to the pipe is 40 m. Taking f=0.01 for the pipe, determine the maximum power transmitted. (b) What is a gear pump and state the difference between an internal and an external type of such pump. [8+8] 2 of 2

3 Code No: RR Set No. 2 III B.Tech I Semester Supplementary Examinations, February 2007 HYDRAULIC MACHINERY AND SYSTEMS ( Common to Mechanical Engineering and Automobile Engineering) Time: 3 hours Max Marks: 80 Answer any FIVE Questions All Questions carry equal marks 1. (a) Derive an expression for the force exerted by a jet of water on an inclined fixed plate in the direction of the jet. (b) A jet of water of diameter 5 cm strikes a fixed plate in such a way that the angle between the plate and the jet is The force exerted in the direction of jet is N. Determine the rate of flow of water. [6+10] 2. What is governing of turbine? Describe with a sketch the working of a system to regulate the speed of a Pelton turbine? [16] 3. (a) Write a short note on the factors influencing the performance of turbines? (b) Obtain an expression for the specific speed of a turbine? [8+8] 4. (a) Show from first principle, the work saved against friction in the delivery pipe of a double-acting reciprocating pump by fitting air vessel is 39.2% (b) A double acting reciprocating pump running at 60 r.p.m has a plunger diameter of 250 mm and a stroke of 500 mm. The delivery pipe is 100mm diameter and 50m long. If the motion of the pump is simple harmonic, find the power required to overcome friction of delivery pipe when a large air vessel is fitted at the center line of the pump. Assume f=0.01. [8+8] 5. (a) Why will the centrifugal pump function only when started at or above minimum speed? (b) Why is the pump called centrifugal pump? How is the centrifugal action present Inside the casing.? [8+8] 6. (a) What do you understand by multistage pump? When do you use them? (b) What do you understand by pumps in parallel? When do you connect the pumps in parallel? [8+8] 7. (a) Describe with neat sketch the working of a hydraulic press. (b) A hydraulic press has diameter of ram 200 mm and of plunger 40 mm. It is provided with a lever for applying force to the plunger. If the ratio of leverage is 10, determine the weight lifted by the press, when the force applied to the level is 100 N. [8+8] 1 of 2

4 Code No: RR Set No Power is to be transmitted hydraulically to a distance of 8 km by means of a number of 10 cm pipes laid horizontally, for which the coefficient of friction may be taken as The pressure at the accumulator is maintained constant at 66.5 Kg/cm 2. Determine the number of pipes required to ensure an efficiency of at least 92 percent when the power delivered is 220 h.p. [16] 2 of 2

5 Code No: RR Set No. 3 III B.Tech I Semester Supplementary Examinations, February 2007 HYDRAULIC MACHINERY AND SYSTEMS ( Common to Mechanical Engineering and Automobile Engineering) Time: 3 hours Max Marks: 80 Answer any FIVE Questions All Questions carry equal marks 1. (a) Obtain an expression for the force exerted by a jet of water on a fixed vertical plate in the direction of the jet. (b) A jet of water of diameter 7.5 cm moving with a velocity of 25 m/s strikes a fixed plate in such a way that the angle between the jet and plate is Find the force exerted by the jet on the plate in the direction normal to the plate and in the direction of the jet. [6+10] 2. A Kaplan turbine runner is to be designed to develop 10,000 bhp. The net available head is 5.50 metres. Assume that the speed ratio is 2.09 and the flow ratio is 0.68, and the overall efficiency is 60%. The diameter of the boss is 1/3 rd of the diameter of the runner. Find the diameter of the runner, its speed and its specific speed. 3. A model of a Francis turbine one-fifth of full size, develops 30.8 KW at 305 rpm, under a head of 2.5 m. Find the speed and power of full size turbine operating under a head of 6 m. [16] 4. (a) Show from first principle, the work saved against friction in the delivery pipe of a double-acting reciprocating pump by fitting air vessel is 39.2% (b) A double acting reciprocating pump running at 60 r.p.m has a plunger diameter of 250 mm and a stroke of 500 mm. The delivery pipe is 100mm diameter and 50m long. If the motion of the pump is simple harmonic, find the power required to overcome friction of delivery pipe when a large air vessel is fitted at the center line of the pump. Assume f=0.01. [8+8] 5. (a) Draw inlet velocity triangle for radial entry of a centrifugal pump. (b) The outer diameter of an impeller of a centrifugal pump is 45cm. The blade angle at outlet is 90 degrees. The speed of impeller is 1500 rpm. The pump works at a manometric efficiency of Calculate the head developed.[8+8] 6. (a) What is the phenomenon of cavitation? Where will it occur in centrifugal pump? (b) When will the kinematiac similarity exist between model and prototype? [8+8] 7. (a) Describe with the help of a schematic diagram the construction, working and performance of a hydraulic ram. [16] 1 of 2

6 Code No: RR Set No. 3 (b) The diameter of ram of a hydraulic press is 300 mm and the diameter of the plunger is 500 mm. If the force applied to the plunger is 500 N, determine the weight lifted by the press. [8+8] 8. Power is to be transmitted hydraulically to a distance of 8 km by means of a number of 10 cm pipes laid horizontally, for which the coefficient of friction may be taken as The pressure at the accumulator is maintained constant at 66.5 Kg/cm 2. Determine the number of pipes required to ensure an efficiency of at least 92 percent when the power delivered is 220 h.p. [16] 2 of 2

7 Code No: RR Set No. 4 III B.Tech I Semester Supplementary Examinations, February 2007 HYDRAULIC MACHINERY AND SYSTEMS ( Common to Mechanical Engineering and Automobile Engineering) Time: 3 hours Max Marks: 80 Answer any FIVE Questions All Questions carry equal marks 1. (a) Obtain an expression for the force on the inclined plate moving in the direction of the jet. Also get the expression for the work done per second by the jet on the plate. (b) A jet of water moving at 12 m/s impinges on a concave shaped vane to deflect the jet through when stationary. If the vane is moving at 5m/s, find the angle of jet so that there is no shock at inlet. Also compute the absolute velocity of jet at exit both in magnitude and direction and the work done per second per N of water. Assume that the vane is smooth. [6+10] 2. A reaction turbine works at 460 rpm under a head of 110 metres. Its diameter at inlet is 115 cms and the flow area is 0.03 metre 2. The angles made by the absolute velocity and relative velocity at inlet are respectively 18 0 and 50 0 with the tangential velocity. Determine : (a) The volume flow rate (b) he H.P. developed (c) The efficiency Assume whirl at outlet to be zero. 3. A model of a Francis turbine one-fifth of full size, develops 30.8 KW at 305 rpm, under a head of 2.5 m. Find the speed and power of full size turbine operating under a head of 6 m. [16] 4. (a) Differentiate between a reciprocating pump and a centrifugal pump. (b) Derive the expression for power required to drive a reciprocating pump. (c) What are the functions of nonreturn valves in a reciprocating pump. [8+4+4] 5. (a) What are the types of centrifugal pumps? Explain with the help of neat sketches where necessary. (b) Draw the out let velocity triangle for radial vane of a centrifugal pump. What is preventing? Why is it needed in a centrifugal pump? [8+8] 6. (a) What do you understand by multistage pump? When do you use them? (b) What do you understand by pumps in parallel? When do you connect the pumps in parallel? [8+8] [16] 1 of 2

8 Code No: RR Set No A hydraulic press has a plunger diameter 20 mm and the ram diameter 160 mm. The stroke of the plunger is 200 mm and the weight lifted by the press is 10 KN. The distance traveled by the weight is 600 mm in 10 minutes. Determine (a) Force applied to the plunger (b) Power required to move the plunger (c) Number of strokes of the plunger. [16] 8. (a) Write a note on the characteristics of a gear pump. (b) Describe in short a vane type of pump. [8+8] 2 of 2

Code No: R Set No. 1

Code No: R Set No. 1 Code No: R05310302 Set No. 1 III B.Tech I Semester Regular Examinations, November 2008 HYDRAULIC MACHINERY AND SYSTEMS ( Common to Mechanical Engineering and Automobile Engineering) Time: 3 hours Max Marks: