#1
| |||
| |||
As you want to get the Sathyabama University B.E in Mechanical Engineering-3rd Semester Fluid Mechanics & Machinery (6C0066) previous years question papers so here is the information of the same for you: Some content of the file has been given here: 1. Define compressibility. 2. What are types of manometers? 3. Define continuity equation. 4. What are the types of notches? 5. What are the minor losses in pipe? 6. What do you mean by vena contracta? 7. Define the specific speed of a pump. 8. What do you mean by cavitation in a pump? 9. What is hydraulic turbine? State its types. 10. What are the types of similitude? PART – B (5 x 12 = 60) Answer All the Questions 11. Calculate the dynamic viscosity of oil, which is used for lubrication between square plate of size 0.8 m x 0.8 m and an inclined plane with an angle of inclination 30. The weight of plate is 300 N and it slides down the inclined plane with uniform velocity of 0.3 m/s. The thickness of oil film is 1.5 mm. (or) 12. Calculate the capillary effect in mm in a glass tube of 4 mm diameter when immersed in (a) Water and (b) mercury. The temperature of the liquid is 20°C and the values of surface tension of water and mercury at 20°C in contact with air are 0.073575 N/m and 0.51 N/m respectively. The angle of contact for water is zero that for mercury 130°. Take density of water as 998 kg/m3. 13. Water flows through a pipe AB 1.2 m diameter at 3 m/s and then passes through a pipe BC 1.5 m diameter, the pipe branches. Branch CD is 0.8 m in diameter and carries one-third of flow in AB. The flow velocity in branch CE is 2.5 m/s. Find the volume rate of flow in AB, the velocity in BC, the velocity in CD and the diameter of CE. (or) 14. Derive the expression for the rate of flow of fluid through venturimeter. 15. Derive the Darcy-Weisbach equation for the pipe. (or) 16. At a sudden enlargement of a water main from 240 mm to 480 mm diameter, the hydraulic gradient rises by 10 mm. Estimate the rate of flow. 17. Discuss the construction and working of a Reciprocating pump. (or) 18. A centrifugal pump is to discharge 0.118 m3 at a speed of 1450 rpm against a head of 25 m. The diameter and width of the impeller at outlet are 250 mm and 50 mm respectively. If the manometric efficiency is 75%, determine the vane angle at the outlet. 19. A pelton wheel is to be designed for the following specifications: Shaft power=11772 kW; Head = 380 m; Speed =750 rpm; overall efficiency = 86%; Jet diameter is not to exceed one-sixth of the wheel diameter. Determine: The wheel diameter (b) The number of jets required and (b) Diameter of jet. Take Kvl = 0.985 and Kul = 0.45 where, Kvl = Coefficient of velocity and Kul=speed ratio. (or) 20. The pressure difference Dp in a pipe of diameter D and length 1 due to viscous flow depends on the velocity V, viscosity µ, density r, obtain an expression for Dr, using Buckingham’s p theorem. 1. What is the difference between kinematic viscosity and dynamic viscosity? State their units of measurements. 2. Define the terms ‘buoyancy’ and ‘centre of buoyancy’. 3. Distinguish between steady flow and unsteady flow. 4. Find the discharge of water flowing over rectangular notch of 3 m length when the constant head of water over the notch is 40 cm. Take coefficient of discharge Cd = 0.6. 5. Define co-efficient of velocity of an orifice. 6. What do you understand by turbulent flow? What factor decides the types of flow in pipes? 7. Define cavitation. What are the effects of cavitation? 8. Define slip and negative slip of a reciprocating pump. 9. What is a draft tube? What are its functions? 10. What do you mean by fundamental units and derived units? PART – B (5 x 12 = 60) Answer All the Questions 11. (a) Explain the following fluid properties (a) Density (b) viscosity (c) Specific weight (d) Capillarity (8) (b) State Newton’s law of viscosity and give examples of its application. (4) (or) 12. (a) Determine the total pressure on a circular plate of diameter 1.5 m which placed vertically in water in such a way that centre of plate is 2 m below the free surface of the water. Find the position of centre of pressure also. (b) A uniform body of size 4 m long X 2 m wide X 1 m deep floats in water. What is the weight of the body if the depth of immersion is 0.6 m? Determine the meta-centric height also. 13. The water is flowing through a pipe having diameters of 20 cm and 15 cm at sections 1 and 2 respectively. The rate of flow through the pipe is 40 liters/s. The section 1 is 6 m above the datum line and section 2 is 3 m above the datum. If the pressure at section 1 is 29.43 N/cm2, Find the intensity of pressure atsection 2. (or) 14. A horizontal venturimeter with inlet and throat diameter 300 mm and 100 mm respectively is used to measure the flow of water. The pressure intensity at inlet is 130 kN/m2 while the vacuum pressure head at throat is 350 mm of mercury. Assuming 3% head lost between the inlet and the throat, find the value of coefficient of discharge for the venturimeter and also determine the rate of flow. 15. (a) Find the discharge through a rectangular orifice 3.0 m wide and 2 m deep fitted to a water tank. The water level in the tank is 4 m above the top edge of the orifice, take co-efficient of discharge Cd = 0.62 (b) A 25 mm diameter nozzle discharges 0.76 m3 of water per minute when the head is 60 m. The diameter of the jet is 22.5 mm. Determine the values of three hydraulic co-efficients. (or) 16. The difference in water surface levels in two tanks which are connected by three pipes in series of lengths 300 m, 170 m and 210 m and diameters 300 mm, 200 mm and 400 mm respectively, is 12 m. Determine the rate of flow of water if co-efficient of friction are 0.005, 0.0052 and 0.0048 respectively, considering: (a) minor losses also (b) neglecting minor losses. 17. (a) Sketch the operating characteristic curves of a centrifugal pump. (4) (b) A centrifugal pump impeller has an outer diameter of 30 cm and an inner diameter of 15 cm. the pump runs at 1200 r.p.m. The impeller vanes are set at a blade angle of 30° at the outlet. If the velocity of flow constant at 2.0 m/s, calculate (i) the velocity and direction of water at outlet, (ii) the head developed assuming a manometric efficiency of 0.85, and (iii) the blade angle at the inlet. (8) (or) 18. (a) Define indicator diagram. Prove that area of indicator diagram is proportional to the work done by the reciprocating pump (b) A single acting reciprocating pump runs at 30 r.p.m., delivers 0.012 m3/s of water. The diameter of the piston is 25 cm and stroke length 50 cm. Determine (i) the theoretical discharge of the pump, (ii) co-efficient of discharge, and (iii) percentage slip of the pump. 19. The pressure difference Dp in pipe of diameter D and length L due to viscous flow depends on the velocity V, viscosity µ and density r. Using Buckingham’s - P theorem, obtain an expression for Dp. (or) 20. (a) What are unit quantities? Define the unit quantities of a turbine. (4) (b) A Kaplan turbine develops 15000 kW power at a head of 30m. the diameter of the boss is 0.35 times the diameter of the runner. Assuming a speed ratio of 2.0, a flow ratio of 0.65 and an overall efficiency of 90% calculate (i) diameter of the runner, (ii) rotational speed and (iii) specific speed (8) 1. What is specific weight and specific gravity of a fluid? 2. Write the relation between absolute pressure and gauge pressure. 3. Define continuity equation and what is the principle behind it. 4. List the types of flow mesureing devices fitted in a pipe flow, which uses the principle of Bernoulli’s theorem. 5. Draw the hydraulic grade line and total energy line. 6. List the types of minor losses in flow through pipes. 7. What is positive displacement pump and rotodynamic pump? 8. Distinguish between pumps in series and pumps in parallel. 9. Write the function of draft tube in turbine outlet. 10. What are the types of similarities? PART – B (5 x 12 = 60) Answer ALL the Questions 11. A vertical cylinder of diameter 180mm rotates concentrically inside another cylinder of diameter 181.2mm. Both the cylinders are 300mm high. The space between the cylinders is filled with a liquid whose viscosity is unknown. Determine the viscosity of the fluid if a torque of 20Nm is required to rotate the inner cylinder at 120 rpm. (or) 12. A U-tube manometer is used to measure the pressure of oil of specific gravity 0.85 flowing in a pipe line. Its left end is connected to the pipe and the right-limb is open to the atmosphere. The centre of the pipe is 100mm below the level of mercury (specific gravity = 13.6)in the right limb. If the difference of mercury level in the two limbs is 160mm, determine the absolute pressure of the oil in the pipe. 13. Derive from basic principle the Euler’s equation of motion in cartesian co-ordinate system and deduce the equation to Bernoulli’s theorem for steady irrotational flow. (or) 14. A venturimeter is inclined at 60° to the vertical and its 150mm diameter throat is 1.2m form entrance along its length. It is fitted to a pipe of diameter 300mm. The pipe conveys gasoline of gravity 0.82 and flowing 0.215 m3/s upwards. Pressure gauge inserted at entrance and throat show the pressure of 0.141 N/mm2 and 0.077 N/mm2 respectively. Determine the coefficient of discharge of the venturimeter. 15. A rectangular orifice 0.6m wide and 0.8m deep is discharging water from a vessel. The top edge of the orifice is 0.4m below the water surface in the vessel Find (a) The discharge through the orifice if Cd = 0.62 (b) The percentage error if the orifice is treated as a small orifice. (or) 16. A pipe line of 600mm diameter is 1.5 km long. To increase the discharge, another line of the same diameter is introduced parallel to the first in the second half of the length. If f = 0.01 and head at inlet is 300mm calculate the increase in discharge. Neglect minor losses. 17. The impeller of a centrifugal pump has an external diameter of 450mm and internal diameter of 200mm and it runs at 1440 rm. Assuming a constant radial flow through the impeller at 2.5 m/s and that the vanes at exit are set back at an angle of 25° determine (a) Inlet vane angle (b) The angle absolute velocity of water at exit makes with the tangent (c) The work done by water. (or) 18. Draw the main components and explain the working of Reciprocating Pumps. 19. A single jet Pelton wheel runs at 300 rpm under a head of 510m. The jet diameter is 200 mm, its deflection inside the bucket is 165° and its relative velocity is reduced by 15% due to friction. Determine (a) Water power (b) Resultant force on the bucket (c) Overall efficiency (or) 20. The discharge Q over a weir depends on the head of water h, acceleration due to gravity g, density r, viscosity µ and the surface tension s. Obtain an expression for the discharge. Contact Details: Sathyabama University Rajiv Gandhi Road, Jeppiaar Nagar, Sholinganallur, Chennai, Tamil Nadu 600119 044 2450 3150 India Map Location: Last edited by GaganD; June 29th, 2019 at 01:43 PM. |