Engineering Thermodynamics Sixteen Marks Questions Bank Unit I- Basic Concept and First Law

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1 Engineering Thermodynamics Sixteen Marks Questions Bank Unit I- Basic Concept and First Law 1. In an isentropic flow through nozzle, air flows at the rate of 600 kg/hr. At inlet to the nozzle, pressure is 2 MPa and temperature is 127 C. The exit pressure is 0.5 MPa. Initial air velocity is 300 mig determine (i) Exit velocity of air (ii) Inlet and exit area of nozzle. (16) (NOV/DEC 2006) 2. A centrifugal pump delivers 2750 kg of water per minute from initial pressure of 0.8 bar absolute to a final pressure of 2.8 bar absolute. The suction is 2 m below and the delivery is 5 m above the centre of pump. If the suction and delivery pipes are of 15cm and 1.0 cm diameter respectively, make calculation for power required to run the pump. (16) (NOV/DEC 2006) 3. A reciprocating air compressor takes in 2 m 3 /min air at 0.11 MPa, 293 K which it delivers at 1.5 MPa, 384 K to an after cooler where the air is cooled at constant pressure to 298 K. The power absorbed by the compressor is 4.15 kw. Determine the heat transfer in (i) the compressor (ii) the cooler. State your assumptions. (16) 4. In a turbo machine handling an incompressible fluid with a density of 1000 kg/m3 the conditions of the fluid at the rotor entry and exit are as given below: Inlet Exit Pressure 1.15 MPa 0.05 MPa Velocity 30 m/sec 15.5 m/sec Height above datum 10 m 2 m If the volume flow rate of the fluid is 40 m 3 /s, estimate the net energy transfer from the fluid as work. (16) Nov / Dec A rigid tank containing 0.4 m3 of air at 400 kpa and 30 C is connected by a valve to a piston cylinder device with zero clearance. The mass of the piston is such that a pressure of 200 kpa is required to raise the piston. The valve is opened slightly and air is allowed to flow into the cylinder until the pressure of the tank drops to 200 kpa. During this process, heat is exchanged with the surrounding such that the entire air remains at 30 C at all times. Determine the heat transfer for this process. (16) Nov / Dec The electric heating system used in many houses consists of simple duct with resistance wire. Air is heated as it flows over resistance wires. Consider a 15 kw electric heating system. Air enters the heating section at 100 kpa and 17 C with a volume flow rate of 150 m 3 /min. If heat is lost from the air in the duct to the surroundings at a rate of 200 W, determine the exit temperature of air. (16) Nov / Dec A gas contained in a cylinder is compressed from 1 MPa and 0.05 m 3 to 2 MPa. Compression is governed by 1.4 V P constant. Internal energy of gas is given by; U = 7.5 PV 425, kj. where P is pressure in kpa and V is volume in m3. Determine heat, work and change in internal energy assuming compression process to be quasi static Also find out work interaction, if the 180 kj of heat is transferred to system betwee n same states. Also explain why it is different from above? (16) April / May 2011

2 8. In a gas turbine installation air is heated inside heat exchanger up to 750 o C from ambient temperature of 27 0 C. Hot air then enters into gas turbine with the velocity of 50 m/s and leaves at C. Air leaving turbine enters a nozzle at 60 m/s velocity and leaves nozzle at temperature of 500 o C For unit mass flow rate of air determine the following assuming adiabatic expansion in turbine and nozzle, a. Heat transfer to air in heat exchanger b. Power output from turbine c. Velocity at exit of nozzle. Take up for air as kj / kg. K. (16)April / May 2011, May / June people attended a farewell party in a small room of size 10 _ 8 m and have a 5 m ceiling. Each person gives up 350 kj of heat per hour. Assuming that the room is completely sealed off and insulated, calculate the air temperature rise occurring in 10 minutes. Assume Cv of air kj/kg K and R = 0:287 kj/kg K and each person occupies a volume of 0.05 m3. Take p = kpa and T = 20 o C. (10) Nov / Dec Air flows at the rate of 0.5 kg/s through an air compressor, entering at 7 m/s, 100 kpa and 0.95 m 3 / kg and leaving at 5 m/s, 700 kpa, and 0.19 m3/kg. The internal energy of air leaving is 90 kj/kg greater than that of the air entering. Cooling water in the compressor jackets absorbs heat from t he air at the rate of 58 kw. (1) Compute the rate of shaft work input to the air in kw (2) Find the ratio of the inlet pipe diameter to outer pipe diameter. (8) Nov / Dec A gas of mass 1.5 kg undergoes a quasi-static expansion which follows a relationship p = a + bv, where a and b are constants. The initial and final pressures are 100 kpa and 200 kpa respectively and the corresponding volumes are 0.20 m 3 and 1.20 m 3. The specific internal energy of the gas is given by the relation U=1.5pv 85 kj / kg. Where p is in kpa and v is in m 3 /kg. Calculate the net heat transfer and the maximum internal energy of the gas attained during expansion. (10) Nov 2012, May A gas flows steadily through compressor. The gas enters the compressor at a temperature of 16 o C, a pressure of 100 kpa, and an enthalpy of kj / kg. The gas leaves the compressor at a temperature of 245 o C, a pressure of 0.6 MPa, and an enthalpy of kj /kg. There is no heat transfer to (or) from the gas as it flows through the compressor. Evaluate the external work done per unit mass of gas when the velocity at entry 80 m /s and that at exit is 160 m/s. 13. A nozzle is a device for increasing the velocity of a steady flowing steam. At the inlet to a certain nozzle, the enthalpy of the fluid passing is 3000 kj / kg and the velocity is 60 m / s. At the discharge end, the enthalpy is 2762 kj / Kg. The nozzle is horizontal and there is negligible heat loss from it. (i) Find the velocity at exit from the nozzle. (ii) If the inlet area is 0.1 m 2 and the specific volume at inlet is m 3 / kg. Find the mass flow rate. (iii) If the specific volume at the nozzle exit is m 3 / kg. Find the exit area of the nozzle. (8) April / May A room of four persons has two fans has two fans, each consuming 0.18 kw power, and three 100 W lamps. Ventilation air at the rate of 80 kg / hr enters with an enthalpy of 84 kj / kg and leaves with an enthalpy of 59 kj / kg. If each person puts out heat at the rate of 630 kj / hr. Determine the rate at which heat is to be removed by a room cooler, so that a steady state is maintained in the room. (7) (Nov / Dec 2007) 15. Three grams of nitrogen gas at 6 atm and 160 o C is expanded adiabatically to double its initial volume, then compressed at constant pressure to its initial volume and then compressed again at constant volume to its initial state. Calculate the net work done on the gas. Draw the p V diagram for the process. Specific heat ratio of nitrogen is 1.4. (12) (May / June 2007)

3 16. Air expands by isentropic process through a nozzle from 784 kpa and 220 o C to an exit pressure of 98 kpa. Determine the exit velocity and the mass flow rate, if the exit area is m 2. (8) (May / June 2007) 17. A blower handles 1 kg / sec of air at 293 K and consumes a power of 15 kw. The inlet and outlet velocities of air are 100 m / sec and 150 m / sec respectively. Find the exit air temperature, assuming adiabatic conditions. ake Cp of air as kj / kg.k. (9) (Nov / Dec 2007) 18. One litre of hydrogen at 273 K is adiabatically compressed to one half of its initial volume. Find the change in temperature of the gas, if the ratio of two specific heats for hydrogen is 1.4. (Nov / Dec 2007) 19. The velocity and enthalpy of fluid at the inlet of a certain nozzle are 50 m / sec and 2800 kj / kg respectively. The enthalpy at the exit of nozzle is 2600 kj / kg. The nozzle is horizontal and insulated so that no heat transfer takes place from it. Find (i) Velocity of the fluid at exit of the nozzle (ii) Mass flow rate, if the area at inlet of nozzle is 0.09 m 2. (iii)exit area of the nozzle, if the specific volume at the exit of the nozzle is m 3 / kg. (Nov / Dec 2007) 20. A three process cycle operating with nitrogen as the working substance has constant temperature compression at 34 o C with initial pressure 100 kpa. Then the gas undergoes a constant volume heating and then polytrophic expansion with 1.35 as index of compression. The isothermal compression requires 67 kj / kg of work. Determine (i) P, v and T around the cycle. (ii) Heat in and out (iii) Net work. For nitrogen gas, Cv = kj / kg.k. May / June A fluid is confined in a cylinder by a spring loaded, frictionless piston so that the pressure in the fluid is a linear function of the volume (p = a + bv). The internal energy of the fluid is given by U= ( pv) where U is in kj, p in kpa and V in cubic meter. If the fluid changes from an initial state of 170 kpa, 0.03 m 3 to final state of 400 kpa, 0.06 m 3, with no work other than that done on the piston, find the direction and magnitude of the work and heat transfer. Nov / Dec Determine the heat transfer and its direction for a system in which a perfect gas having molecular weight of 6 is compressed from kpa, 20 o C to a pressure of 600 kpa following the law pv 1.3 = constant. Take specific heat at constant pressure of gas as 1.7 kj / kg. K. May / June Air at a temperature of 15 o C passes through a heat exchanger at a velocity of 30 m/s where its temperature is raised to 800 o C. It then enters a turbine with the same velocity of 30 m/s and expands until the temperature falls to 650 o C. On leaving the turbine, the air is taken at a velocity of 60 m/s to a nozzle where it expands until the temperature has fallen to 500 o C. If the air flow rate is 2 kg /s, Calculate (a) the rate of heat transfer to the air in the heat exchanger (b) the power output from the turbine assuming no heat loss, and (c) the velocity at exit from the nozzle, assuming no heat loss. Take the enthalpy of air as h = Cp.t, where Cp is the specific heat equal to kj / kg.k and t is the temperature.

4 Theory questions 1. Considering a system which changes its state, prove that the internal energy is a point function. (8) Nov / Dec Define the following terms (1) Thermodynamics (2) Macroscopic approach (3) Continuum. Nov / Dec 2012, Nov / Dec 2011 (6) Deduce the expression for the displacement work in an isothermal process. (4) (May / June 2007) Describe steady flow energy equation and deduce suitable expression for the expansion of gas in a gas turbine with suitable assumptions. (8) (May / June 2007) (i)derive the steady flow energy equation, stating the assumptions made. (6) (ii)prove that energy is a property of a system. (5) (iii)enumerate and explain the limitations of first law of thermodynamics. (5) May / June 2013 Define enthalpy. How is it related to internal energy? (4) Nov / Dec 2012 Derive steady flow energy equation and reduce it for turbine, pump, nozzle and a heat exchanger. (16) Nov / Dec 2013 Briefly explain the following: (i) Point function and path function. (4) (ii) Property, state, process and path (8) (iii) Quasi- static process. (4) Nov / Dec 2013

5 V.S.B. ENGINEERING COLLEGE, KARUR Department of Mechanical Engineering Question Bank Sub Code/Name: CE6451-Fluid Mechanics & Machinery Year/Sem: II / III UNIT- I PART-A 1. Define viscosity? 2. What is compressibility? 3. Define dynamic viscosity? 4. What is cause for viscosity? 5. Give some example of surface tension? 6. Define vapour pressure? 8. Give the Euler s equation of motion? 9. What is Bernoulli s equation for real fluid? 10. State momentum equation and Impulse momentum equation? 11. State moment of momentum equation? 12. State Bernoulli s theorem? 13. Differentiate steady and unsteady flow? 14. State the assumptions in Bernoulli s equation. PART-B 1. a) Derives Euler s Equation of Motion and proves the Bernoulli s equation. (12 Marks) b) Define the terms: i) Steady and unsteady flows ii) Specific weight (4 Marks) 2. a) Define the terms: i) Kinematics of flow ii) Uniform and non-uniform flows iii) Rotational and irrotational flows (6 Marks) b) The Velocity Distribution for flow over a flat plate is given by u=(2/3)y-y2, Where u is the point velocity in metre per second at a distance y metre above the plate. Determine the shear stress aty=0 and y=15 cm. Assume dynamic viscosity as 8.63 poises (10Marks) 3. a) A pipe 200mm long has a slope of 1in100 and tapers from 1.2m diameter at thehigh end to 0.6m diameter at the low end and carries 100litres/sec of oil (Sp.gr.=0.8). If the pressure gauge at the high end reads 60kN/m², determine i)velocities at the two ends and ii) pressure at the lower end. (12 Marks) b) One litre of crude oil weighs 9.6 N. Calculate its Specific weight and density (4 Marks) 4. Two large plane surfaces are 150mm apart. The space between the surfaces is filled with oil of viscosity 0.972Ns/m². A flat thin plate of o.5m² area moves through the oil at velocity of 0.3m/sec. Calculate the drgg force i) When the plate is in the middle of the two plane surfaces and ii)when the thinplate is at a distance of 30mm from one of the planes.(16 Marks) 5. a) Derive the three dimensional Continuity equation. (10 Marks) b) Define the following i) Compressibility ii) Vapour pressureiii) Capillarity (6Marks) 6. a) Two plates are placed at a distance of 0.15mm apart. The lower plate is fixed while the upper plate having surface area 1.0 m2 is pulled at 0.3nm/s. Find the force and power required to maintain this speed, if the fluid separating them is having viscosity 1.5 poise. (8 Marks) b) An oil film of thickness 1.5 mm is used for lubrication between a square plate of size 0.9m 0.9m and an inclined plane having an angle of inclination The weight of square plate is N and its slides down the plane with a uniform velocity of 0.2 m/s. find the dynamic viscosity of the oil. (8 Marks) 7. A pipe 300m long has a slope of 1 in100 and tapers from 1m diameter at the high end to 0.5m at the low end. The quantity of water flowing is 5400 m3/min. If the pressure at the high end is N/m², find the pressure at the low end. What is the change in pressure if the head loss between the two sections is 0.45m of water? (16 Marks)

6 liters/sec of water is flowing in a pipe having a diameter of 300mm. If the pipe is bent by 135 (that is change from initial to final direction is 135 ), find the magnitude and direction of the resultant force on the bend. The pressure of water flowing is 39.24N/cm². (16 Marks) 9. The diameter of a pipe gradually reduces from 1m to 0.7m. The pressure intensity at centerline of 1m section 7.848kN/m² and the rate of flow of water through the pipe is 600liters/sec. Find the intensity of pressure at the centerline of 0.7m section. Also determine the force exerted by flowing water on transition of the pipe. (16 Marks) 10.a) State the momentum equation. How will you apply momentum equation for determining the force exerted by a flowing fluid on a pipe bend? (12 Marks) b) Define Moment of Momentum equation. Where this equation is used? (4 Marks) UNIT- II PART-A 1. What do you mean by the term Boundary Layer? 2. What is laminar sub-layer? 3. Define Momentum thickness in Boundary Layer concept. 4. Sketch the development of Boundary layer over a flat plate. 5. Define the term Turbulence 6. Define: Hydraulic Gradient Line 7. Define: Total gradient Line 8. What is the expression for head loss due to friction in Darcy formula? 9. What are the factors to the determined when viscous fluid flows through the circular pipe? 10. What do you understand by the terms a) major energy losses, b) minor energy losses? 11. Give an expression for loss of head due to sudden enlargement of the pipe :- 12. Give an expression for loss of head due to an obstruction in pipe 13. What are the basic educations to solve the problems in flow through branched pipes? 14. What is Dupuit s equation? PART-B 1. a) Define Displacement thickness. Derive an expression for the Displacement thickness.(10 Marks) b) Define: i) Laminar Boundary layer ii) Laminar Sub-layer (6 Marks) 2. a) A thin plate is moving in still atmospheric air at a velocity of 5m/sec. The length of the plate is 0.6m and width 0.5m. Calculate i) the thickness of the boundary layer at the end of the plate and ii) Drag force on one side of the plate. Take density of air as 1.24 kg/m3 and kinematic viscosity 0.15 strokes. (10 Marks) b) What do you understand by the term Boundary layer and Boundary Layer theory? (6 Marks) 3. a) A plate of 600mm length and 400mm wide is immersed in a fluid of specific gravity 0.9 and kinematic viscosity 10-4 m²/sec. The fluid is moving with a velocity of 6 m/sec. Determine i) boundary layer thickness ii) shear stress at the end of the plate, and iii) drag force on one side of the plate. (12 Marks) b) Differentiate Laminar & Turbulent Flow. (4 Marks) 4. a) What do you understand by the terms: Major energy losses and Minor energy losses (8 Marks) b) Obtain expression for head loss in a sudden expansion in the pipe. List all the assumptions made in the derivation. (8 Marks) 5. a) Derive the darcy-weisbach equation. (10 Marks) b) Water is flowing through a pipe of diameter 250mm with a velocity of 3m/sec. Find the head loss due to friction for a length of 5.5m, if the coefficient of friction f is given by f = [0.03+(0.08/Re0.3)] where kinematic viscosity = 0.01strokes. (6 Marks)

7 6. The difference in water level between two tanks which are connected by three pipes in series is 15m. Lengths and diameters of these pipe are 300m, 150m, 200m and 30cm, 20cm, and 30cm respectively. Find the discharge through the pipe line and tabulate all losses if friction factor for three pipes are taken as 0.02, and 0.03 (16 Marks) 7. a) A sudden enlargement of a water main from 230mm to 460mm diameter, the hydraulic gradient rises by 10mm. Estimate the discharge. (10 Marks) b) Obtain expression for head loss in a sudden contraction in the pipe. (6 Marks) 8. Determine the length of an equivalent pipe of diameter 20cm and friction factor is 0.02 for a given pipe system discharging 0.1 m3/sec. The pipe system consists of the following. i) 10m line of 20cm diameter with friction factor 0.03, ii) three 90 bend with k=0.5 for each, iii) two sudden expansion of diameter 20cm to 30cm, iv) a 15cm line of 30cm diameter with friction factor is and v) a global valve fully open with k=10. (16 Marks) 9. Two reservoirs whose water surface elevations differ by 40m are connected by a pipe line 30cm in diameter and 3km long. In order to increase the discharge, an additional pipe line 20cm in diameter and 1.5km long is laid parallel from the midpoint of the first one upto the lower reservoir. What is the increase in discharge due to newly laid pipe? Assume friction factor f = 0.02 (16 Marks) UNIT- III PART-A 1. Define Dimensional Analysis 2. Define dimensionally homogeneous equation. 3. What are the methods of dimensional analysis? 4. State Buckingham s Π theorem 5. What is dimensionless number? 6. What are the conditions for hydraulic similitude? 7. Explain the significance of Froude Model law 8. Explain the terms: Model and Prototype 9. List advantages of Dimensional Analysis. 10. Explain Model analysis. PART-B 1. a) Explain with example, dimensional homogeneity of a physical equation. (6 Marks) b) Describe in detail the method of dimensional analysis using Buckingham s π theorem. 2. a) Define i) Geometric similarity ii) Dynamic similarity iii) Kinematic similarity. (6 Marks) b) The efficiency of a fan η depends upon following factors : 1) Density ρ 2) Dynamic viscosity μ 3) Diameter D 4) Discharge Q and 5) Angular velocity ω, Show that η = Φ [μ/d²ωρ, Q/D3ω ]. 3. The pressure difference ΔP in a pipe of diameter D and length L due to turbulence flow depends on the velocity V, viscosity μ, density ρ and roughness K. Using Buckingham s π theorem, obtain an expression for ΔP. (16 Marks) 4. The discharge Q through an oil ring depends on the diameter D of oil ring, speed N rpm, mass density ρ of oil, absolute viscosity μ of oil, surface tension σ and specific weight ע of oil. Show that Q = ND3 f [ μ / ρnd², σ / ρn²d3, ע / ρn²d ] (16 Marks) 5. Power P developed by a water turbine depends upon rotational speed N, operational head H, diameter D, breath B of runner, density ρ, viscosity μ and gravity g show that P = ρd 5 N 5 Φ[H/D, B/D, ρd²n/μ, ND/(gH)1/2 ] (16 Marks) 6. Torque T of a propeller depends upon density of liquid ρ, viscosity μ, speed N, linear velocity V, diameter of the propeller shaft D. Using Buckingham s π theorem show that T= ρn²d 5 f[ ND/V, ρnd²/μ ] (16 Marks)

8 7. a) A pipe of diameter 1.5m is required to transport an oil of specific gravity 0.9 and viscosity 3X10-2 poise at the rate of 3000lit/sec. Tests were conducted on a 15cm diameter pipe using water at 20 C. Find the velocity and rate of flow in the model. Viscosity of water at 20 C is 0.01poise. (8 Marks) b) The ratio of length of a sub-marine and its model is 30:1. The speed of the sub-marine (prototype) is 10m/sec. The model is to be tested in a wind tunnel. Find the speed of air in wind tunnel. Also determine the ratio of drag (resistance) between the model and prototype. Take the value of kinematic viscosity for sea water and air as 0.012strokes and 0.016strokes respectively. The density for sea water and air is given as 1030kg/m3 and 1.24kg/m3 respectively. (8 Marks) 8. a) The pressure drop in an aero-plane model of size 1:40 of its prototype is 80N/cm². The model is tested in water. Find the corresponding pressure drop in the prototype. Take density of air 1.24 kg/m 3. The viscosity of water is 0.01poise while the viscosity of air is poise. (10 Marks) b) Derive Euler, Froude and Weber numbers. (6 Marks) UNIT- IV PART-A 1. What is meant by Pump? 2. What is meant by Priming? 3. Differentiate between the single acting pump and double acting pump 4. What are the functions of air vessels? 5. Mention main components of Centrifugal pump 6. Define slip, percentage slip and negative slip of a reciprocating pump 7. Define Manometric efficiency 8. Define Mechanical efficiency. 9. Define overall efficiency. 10. Define speed ratio, flow ratio. 11. Mention main components of Reciprocating pump. 12. What is the use of air vessel? 13. What is meant by rotary pump? 14. What is indicator diagram? 15. What is meant by Cavitations? PART-B 1. A radial flow impeller has a diameter 25cm and width 7.5cm at exit. It delivers 120litres of water per second against a head of 24m at 1440rpm. Assuming the vanes block the flow area by 5% and hydraulic efficiency of 80%. Estimate the vane angle at exit. Also calculate the torque exerted on the driving shaft if the mechanical efficiency is 95%. (16 Marks) 2. Find the power required to drive a centrifugal pump which delivers 0.04m 3 /sec of water to a height of 20m through a 15cm diameter pipe and 100m long. The overall efficiency of the pump is 70% and coefficient of friction is 0.15 in the formula Hf= 4flv 2 / 2gd. (16 Marks) 3. A centrifugal pump having outer diameter equal to 2 times the inner diameter and running at 1200rpm works against a total head of 75m. The velocity of the flow through the impeller is constant and equal to 3m/sec. the vanes are set back at an angle of 30 at outlet. If the outer diameter of the impeller is 600mm and width at outlet is 50mm. Determine i) Vane angle at inlet (ii) Work done per sec by the impeller iii) Manometric efficiency. (16 Marks) 4. The impeller of a centrifugal pump has an external diameter of 450mm and internal diameter of 200mm and it runs at 1440rpm. Assuming a constant radial flow through the impeller at 2.5m/sec. and that the vanes at exit are set back at an angle of 25. Determine i)inlet vane angle ii) The angle, absolute velocity of water at exit makes with the tangent and iii) The work done per N of water. (16 Marks)

9 PART-B 1. A jet of water having velocity of 20m/sec strikes a curved vane, which is moving with a velocity of 10m/sec. The jet makes an angle of 20 with the direction of motion of vane at 5. The diameter and stroke of a single acting reciprocating pump are 200mm and 400mm respectively, the pump runs at 60rpm and lifts 12litres of water per second through a height of 25m. The delivery pipe is 20m long and 150mm in diameter. Find i) Theoretical power required to run the pump ii) Percentage of slip iii) Acceleration head at the beginning and middle of the delivery stroke. (16 Marks) 6. The cylinder of a single-acting reciprocating pump is 15 cm in diameter and 30 cm in stroke. The pump is running at 30 r.p.m and discharge water to a height of 12 m. the diameter and length of the delivery pipe are 10 cm and 30 m respectively. If a large air vessel is fitted in the delivery pipe at a distance of 2 m from the centre of the pump, find the pressure head in the cylinder. (i) at the beginning of the delivery stroke, and (ii) in the middle of the delivery stroke. Take f= Explain the working principle of screw pump and gear pump with neat diagram in detail. 8. Explain the working principle of single and double acting reciprocating pumps with neat diagram in detail: Also explain the effects of inertia pressure and friction on the performance of the pump using indicator diagrams with and without air vessel. 9. Show the workdone by a reciprocating pump is equal to the area of the indicator diagram. 10. Classify pumps. Explain the working of a double acting reciprocating pump with a neat diagram. 11. Explain in detail about the performance curves for pumps 12. Write briefly on the following. (i) Rotary pumps and their classifications. (8) (ii) Indicator diagram for reciprocating pump. (8) 13. Calculate the work saved by fitting an air vessel for a double acting single cylinder reciprocating pump. 14. Explain in detail the working principle and construction of rotary pumps with neat sketch. 15. Discuss on the following: working of double acting pump, indicator diagram, acceleration head, and friction head. 16. With neat sketches, discuss about the rotary positive displacement pump. UNIT- V PART-A 1. What is a hydraulic turbine? 2. How will you classify the turbine? 3. Differentiate between the reaction and impulse turbine 4. Define specific speed of turbine 5. Give example for a low head, medium head and high head turbine. 6. What is Draft tube? 7. Define specific speed. 8. What is cavitation? How can it be avoided in reaction turbine? 9. Define the term Governing of a turbine 10. What are the functions of Surge tank? 11. Differentiate between an inward and an outward flow reaction turbines. 12. List out advantages of Francis turbine

10 inlet and leaves an angle of 130 to the direction of motion of vane at outlet. Calculate i) Vane angles, so that the water enters and leaves the vane without shock. ii) work done per second per unit weight of water striking the vane per second. (16 Marks) 2. A jet of water having velocity of 15m/sec strikes a curved vane which is mo ving with a velocity of 5m/sec. The vane is symmetrical and it so shaped that the jet is deflected through 120. Find the angle of the jet at inlet of vane so that there is no shock. What is the absolute velocity of jet at outlet in magnitude and direction and the work done per unit weight of water? Assume the vane to be smooth. (16 Marks) 3. A jet of water having velocity of 30m/sec strikes a series of radial curved vanes mounted on a wheel which is rotating at 200rpm. The jet makes an angle of 20 with the tangent to the wheel at inlet and leaves the wheel with a velocity of 5m/sec at an angle of 130 to the tangent to the wheel at outlet. Water is flowing from outward in a radial direction. The outer and inner radii of the wheel are 0.5m and 0.25m respectively. Determine i) Vane angles at inlet and outlet ii) work done per unit weight of water iii) efficiency of wheel. (16 Marks) 4. The penstock supplies water from a reservoir to the pelton wheel with a gross head of 500m. One third of the gross head is lost in friction in the penstock. The rate of flow of water through the nozzle fitted at the end of the penstock is 2m3/sec. The angle of deflection of the jet is 165. Determine the power given by the water to the runner and hydraulic efficiency of the pelton wheel. Take speed ratio=0.45 and Cv=1 (16 Marks) 5. A pelton wheel having a mean bucket diameter of 1m and is running at 1000rpm. The net head on the pelton wheel is 700m. If the side clearance angle is 15 and discharge through nozzle is 0.1m 3 /sec. Find i) Power available at the nozzle ii) Hydraulic efficiency of the turbine. (16 Marks) 6. A reaction turbine works at 450rpm under a head of 120m. Its diameter at inlet is 120cm and the flow area is 0.4m². The angles made by absolute and relative velocities at inlet are 20 and 60 respectively with the tangential velocity. Determine i) The volume flow rate ii) The power developed iii) Hydraulic efficiency (16 Marks) 7. As inward flow reaction turbine has external and internal diameters as 1m and 0.6m respectively. The hydraulic efficiency of the turbine is 90% when the head on the turbine is 36m.The velocity of flow at outlet is 2.5m/s and discharge at outlet is radial. If the vane angle at outlet is 15 and width of the wheel is 100mm at inlet and outlet, Determine i) the guide blade angle ii) speed of the turbine iii) vane angle of the runner at inlet iv) volume flow rate of turbine v) power developed. (16 Marks) 8. A Pelton turbine is required to develop 9000kW when working under a head of 300m the impeller may rotate at 500rpm. Assuming a jet ratio of 10 and an overall efficiency of 85%. Calculate i) quantity of water required ii) diameter of wheel iii) Number of jets iv) Number and size of bucket on the runner. (16 Marks) 9. The following data is given for a Francis turbine. Net head = 80m, Speed = 700rpm, Shaft power = 300kW, Overall efficiency = 80%, Hydraulic efficiency = 90%, flow ratio =0.2, and breadth ratio = 1. The thickness of vane occupies 4% of circumferential area of the runner, velocity of flow is constant at inlet and outlet and discharge is radial at outlet.determine i) Diameters of runner at inlet and outlet, assume D 2 =D 1 /2. ii) Width of wheel at inlet iii) Guide blade angles iv) runner vane angles at inlet and outlet. (16 Marks) 10. i) Draw a neat sketch of Kaplan turbine, name the parts and briefly explain the working.(8 Marks) 11. ii) Define specific speed of the turbine? Derive an expression for the specific speed.(8 Marks) 12. Draw a neat sketch of Pelton wheel turbine, name the parts and briefly explain the working.

11 13. Draw a neat sketch of reaction turbine, name the parts and briefly explain the working. 14. Draw a neat sketch of Francis turbine, name the parts and briefly explain the working. ===================================================================== QUESTION BANK -MANUFACTURING TECHNOLOGY-I UNIT-I METAL CASTING PROCESSES 1. Define casting. 2. What is foundry? 3. Name the properties of moulding sand 4. Name the materials used for making patterns 5. Name any five types of commonly used patterns. 6. What are the ingredients present in the moulding sands? 7. Name the different types of moulding sands. 8. Write the composition of good moulding sand? 9. Differentiate the terms 'mould' and 'core'. 10. When do you make core (or) what is function of core in moulding sand? 11. What are the processing steps involved in the core making process? 12. Define permeability number? 13. What are the advantages of shell moulding? 14. List the factors to be considered in the choice of metal melting furnace? 15. Name the different types of furnaces are most commonly used in foundries. 16. Name the different zones in cupola furnace? 17. What are chaplets? 18. What are the reasons for providing pattern allowances? 19. Mention the specific advantages of carbon di oxide (CO 2 ) process? 20. Give any two merits and demerits of investment casting process? 21. List out the various defects. 22. Write short notes on inspection procedure for casting? 23. How casting defects are identified? 24. What is core venting? 25. Which processes is called Lost wax processes? Why? PART-B 01. State the different type of mould. Write a short note on Green sand mould and shell moulding. 02. Discuss the properties of moulding sand. 03. Explain the CO 2 process of core making state its advantages and applications. 04. What are the pattern allowances? Explain briefly each 05. Explain the types of pressure die casting with suitable sketches? 06. Explain with the neat sketch of a cupola furnace? 07. Explain the working principle of sand slinger and jolt machine. 08. Discuss the casting defects and their inspection methods. 09. Explain in detail the working principles of the following a) Investment casting b) Centrifugal casting 10. Explain the various Non-destructive inspection methods of cast products. UNIT-II JOINING PROCESSES PART-A 1. What are different methods of welding you know? 2. What is the purpose of flux? (April/May-2008) 3. List out any four arc welding equipment (May/June-2006) 4. Define resistance welding process. (May/June-2007) 5. Mention any two merits and Demerits of Laser beam welding.

12 6. Why flux is coated in filler rods? (Nov/Dec-2008) 7. What is the application of carburizing flame? (Nov/Dec-2009) 8. What are the diameter and length of the electrodes available in the market? (Dec-09) 9. Mention the various types of resistance welding. 10. Define friction welding process. 11. How does brazing differ from braze welding? (Nov/Dec-08) 12. List out the classification of brazing methods? 13. What are the types of adhesives used in permanent joint? 14. Define soldering and brazing? 15. List out the types of soldering methods? 16. State three merits and demerits of adhesive bonding? 17. Define welding process. 18. Define fusion welding. 19. What are different method of welding you know? 20. Mention any two advantages of D.C and A. C welding. 21. What do you under stand by straight polarity? 22. When is the straight polarity used for arc welding? 23. What is the purpose of coating on an arc - welding electrode? 24. What are the two main different of consumable electrode and non - consumable electrode? 25. How does MIG welding differ from TIG welding? 26. What is the main different between upset butt welding and flash butt welding? 27. Define plasma arc welding? PART-B 1) Explain the TIG and MIG system of welding. Give the application of each. (Nov/Dec- 2009) 2) Illustrate the thermit welding process with neat sketch and also state its applications (2009) 3) (i) Explain the features of neutral, reducing and oxidizing flames. (April/May-2008) (ii)explain gas metal arc welding (GMAW) process with neat sketch 4) With a neat sketch, explain the process of submerged arc welding. 5) Describe the various types of brazing methods 6) Explain various types of soldering methods? 7) Explain the method of laser beam welding and give their applications 8) Explain the method of electron beam welding and given their applications 9) Describe plasma Arc welding and given their applications 10) Describe and explain Ultrasonic welding and give their applications 11) Explain Thermit welding and given their applications 12) What is frication welding? give their advantage and limitations 13) Distinguish between brazing, soldering and welding. 14) Write briefly on testing and inspection. UNIT-III BULK DEFORMATION PROCESSES PART-A 1. Define forging processes? 2. Write short notes on roll forging? 3. What are the disadvantages of forging processes? 4. What are the four major drawbacks of hot working? 5. List out the classification of cold working process? 6. List out the classification of cold working process? 7. What are the disadvantages of forging processes? (Nov/Dec-2009) 8. Distinguish between Press forging and Drop forging? 9. How are seamless tubes produced? (April/May 2008)

13 10. What is skew rolling? (Nov/Dec-2008) 11. What is Sejournet process? (Nov/Dec Define hot working and cold working of metals? 13. What is the difference between a bloom and a billet? (May/June-07) 14. Define forging processes? 15. Write short notes on roll forging? 16. Name the different types of forging machine? 17. Classify the types of extrusion? (May/June-06) 18. What is impact extrusion? (May/June-07) 19. Define cold working of metals 20. Define re crystallization temperature 21. Give some examples for mechanical working of metals 22. Define forging 23. Give some basic forging operations 24. Define extrusion ratio 25. Define tube drawing 26. Define degree of drawing 27. Name four different press-working operations 28. What are the defects in forging operations? PART-B 1. What is shape rolling? Mention the products of shape rolling and explain production of any one of the product with sketches. (Nov/Dec-2008) 2. Explain briefly with neat sketch, the process of wire drawing? (April/May -08) 3. Differentiate between Open-die forging & Closed die forging. (Nov/Dec-08) 4. Explain briefly with neat sketches direct and indirect extrusion process.(april/may Describe the different kinds of rolling mills with neat sketches and also mention the merits & limitations. (April/May -08) 6. Compare the difference between Hot and Cold extrusion process?(may/june-07) 7. Distinguish between wire drawing and tube drawing. (May/June-09) 8. Explain the hot working and cold working with suitable examples 9. Define rolling and discuss according to the classification 10. Discuss the various forging operations. 11. Give the advantage of press forging over drop forging 12. What are the defects in forgings? Explain it. 13. How the pipe and tubes are manufacturing? 14. Define drawing and discuss the classification with neat sketch UNIT-IV SHEET METAL PROCESSES Part-A (2 Marks) 1.Define bending processes. 2. What is sheet metal work? 3. write down any four sheet metal characteristics 4. What is meant by clearance? 5. What is stretching? 6. Define the term spring back. 7. How force exerted on the form block is calculated 8. What are the formability test methods? 9. What is super plasticity of metals? 10.What is sheet metal work? 11. State the advantages of press working operations. 12. What do you mean by minimum bend radius?(nov-dec-2008) 13. Define limiting drawing ratio. (Nov-Dec-2008) 14. Define the term spring back. 15. List out the special forming process in sheet metal work. 16. How is hydro-forming similar to rubber forming? (April/May-2008) 17. What is super plastic forming operations? (May/June-2006) 18. Describe briefly power spinning process.

14 19. What is peen forming process? Part-B (16 Marks) 1. Describe shearing operations in a sheet metal work with a neat sketch 2. Describe various types of bending operations with its neat sketches 3. Explain any one method of stretch forming operation with a neat sketch 4. Explain hydro forming process with its neat sketches. State their advantage and applications 5. Explain the power spinning process with a neat sketch.give their applications 6. How magnetic pulse forming process is carried out on sheet metal? 7. Explain peen forming process with a neat sketch 8. What is super plastic of metal? how this process is carried out on sheet metals? 9. Write short notes on following with neat sketches. (April/May-2008) (i) Electro hydraulic forming process (ii) Name and describe the common bending operations. 10 Explain the principle of magnetic pulse forming with neat sketches. (May/June-2006) 11.Describe the Stretch forming operations with neat sketches. (May/June-2006) 12.What is explosive forming? Explain with neat sketches? (Nov/Dec-2008) UINT-V MANUFACTURING OF PLASTIC COMPONENTS PART-A (2 Marks) 1. How the plastic is defined? 2. Give some examples of additives 3. Give some examples for thermosetting plastics. 4. Give some example of thermo plastics. 5. Give some additives added to the manufacturing of rubber. 6. What are the processes of thermoplastics? 7. What are the two types of injection moulding? 8. What are the types of compression moulding? 9. define co polymerization 10. What are the foamed plastics? 11. What are the types of plastics? (AU-2008) 12. What are the characteristics of thermoplastics? (AU-2006) 13. What is film blowing? (AU-2007) 14. List out the materials for processing plastics Part-B (16 Marks) 1. What are the characteristics of the forming and shaping processes? 2. What are the types of moulding and thermoplastics? 3. Explain the working principles and application of a. injection moulding b. blow moulding c. rotational moulding d. film blowing 4. Explain the thermoforming process 5. Explain induction and ultrasonic methods. 6. Explain working and principle of applications of a. compression moulding b. transfer moulding 7. Describe briefly the process of injection moulding as used for producing plastic components. 8. What is film blowing? What are its relative merits and demerits?

15 QUESTION BANK CE STRENGTH OF MATERIALS UNIT I STRESS STRAIN DEFORMATION OF SOLIDS PART- A (2 Marks) 1. What is Hooke s Law? 2. What are the Elastic Constants? 3. Define Poisson s Ratio. 4. Define: Resilience 5. Define proof resilience 6. Define modulus of resilience. 7. Define principal planes and principal stresses. 8. Define stress and strain. 9. Define Shear stress and Shear strain. 10. Define elastic limit. 11. Define volumetric strain. 12. Define tensile stress and compressive stress. 13. Define young s Modulus. 14. What is the use of Mohr s circle? 15. Define thermal stress. 16. Define Bulk modulus. 17. What is modulus of rigidity? 18. Define factor of safety. 19. State the relationship between young s modulus and modulus of rigidity What is compound bar? PART- B (16 Marks) 1. A Mild steel rod of 20 mm diameter and 300 mm long is enclosed centrally inside a hollow copper tube of external diameter 30 mm and internal diameter 25 mm. The ends of the rod and tube are brazed together, and the composite bar is subjected to an axial pull of 40 kn. If E for steel and copper is 200 GN/m2 and 100 GN/m2 respectively, find the stresses developed in the rod and the tube also find the extension of the rod. 2. A cast iron flat 300 mm long and 30 mm (thickness) 60 mm (width) uniform cross section, is acted upon by the following forces : 30 kn tensile in the direction of the length 360 kn compression in the direction of the width 240 kn tensile in the direction of the thickness. Calculate the direct strain, net strain in each direction and change in volume of the flat.assume the modulus of elasticity and Poisson s ratio for cast iron as 140 kn/mm 2 and 0.25 respectively. 3. A bar of 30 mm diameter is subjected to a pull of 60 kn. The measured extension on gauge length of 200 mm is 0.09 mm and the change in diameter is mm. calculate the Poisson s ratio and the values of the three modulus.

16 4. The bar shown in fig. is subjected to a tensile load of 160 KN. If the stress in the middle portion is limited to 150 N/mm 2, determine the diameter of the middle portion. Find also the length of the middle portion if the total elongation of the bar is to be 0.2mm. young s modulus is given as equal to 2.1 x 10 5 N/mm A member ABCD is subjected to point loads P1, P2, P3, P4 as shown in fig. calculate the force P2 necessary for equilibrium, if P1 = 45 KN, P3 = 450 KN and P4 = 139 KN. Determine the total elongation of the member, assuming the modulus of elasticity to be 2.1 x 10 5 N/mm A steel rod of 20mm diameter passes centrally through a copper tube of 50mm external diameter and 40mm internal diameter. The tube is closed at each end by rigid plates of negligible thickness. The nuts are tightened lightly home on the projecting parts of the rod. If the temperature of the assembly is raised by 50 C, calculate the stress developed in copper and steel. Take E for steel and copper as 200 GN/m 2 and 100 GN/m 2 and α for steel and copper as 12 x 10-6 per C and 18 x 10-6 per C. 7. Two vertical rods one of steel and the other of copper are each rigidly fixed at the top and 50cm apart. Diameters and lengths of each rod are 2cm and 4m respectively. A cross bar fixed to the rods at the lower ends carries a load of 5000 N such that the cross bar remains horizontal even after loading. Find the stress in each rod and the position of the load on the bar. Take E for steel = 2 x 10 5 N/mm 2 and E for copper = 1x 10 5 N/mm 2.

17 8. Drive the relationship between modulus of elasticity and modulus of rigidity. Calculate the modulus of rigidity and bulk modulus of a cylindrical bar of diameter 30 mm and of length 1.5 m if the longitudinal strain in a bar during a tensile stress is four times the lateral strain. Find the change in volume, when the bar is subjected to a hydrostatic pressure of 10 N/mm2. Take E = 1X 10 5 N/mm 2 A) what are the different types of machining operations that can be performed on a lathe? And explain any six in detail. 9. (A). Find the young s modulus of a rod of diameter 30mm and of length 300mm which is subjected to a tensile load of 60 KN and the extension of the rod is equal to 0.4 mm. (B). The ultimate stress for a hollow steel column which carries an axial load of 2MN is 500 N/mm 2.If the external diameter of the column is 250mm, determine the internal diameter Take the factor of safety as The extension in a rectangular steel bar of length 400mm and thickness 3mm is found be 0.21mm.The bar tapers uniformly in width from 20mm to 60mm E for the bar is 2x 10 5 N/mm 2.Determine the axial load on the bar. UNIT II BEAMS LOADS AND STRESSES PART- A (2 Marks) 1. State the different types of supports. 2. What is cantilever beam? 3. Write the equation for the simple bending theory. 4. What do you mean by the point of contraflexure? 5. What is mean by positive or sagging BM? 6. Define shear force and bending moment. 7. What is Shear stress diagram? 8. What is Bending moment diagram? 9. What are the different types of loading? 10. Write the assumption in the theory of simple bending. 11. What are the types of beams? 12. When will bending moment is maximum. 13. Write down relations for maximum shear force and bending moment in case of a cantilever beam subjected to uniformly distributed load running over entire span. 14. Draw the shear force diagram for a cantilever beam of span 4 m and carrying a point load of 50 KN at mid span. 15. Sketch (a) the bending stress distribution (b) shear stress distribution for a beam of rectangular cross section. 16. A cantilever beam 3 m long carries a load of 20 KN at its free end. Calculate the shear force and bending moment at a section 2 m from the free end. 17. Derive the relation between the intensity of load and shear force, in bending theory. 18. A clockwise moment M is applied at the free end of a cantilever. Draw the SF and BM diagrams for the cantilever.

18 19. What is maximum bending moment in a simply supported beam of span L subjected to UDL of w over entire span? 20. What is mean by negative or hogging BM? PART- B (16 Marks) 1. Three blanks of each 50 x200 mm timber are built up to a symmetrical I section for a beam. The maximum shear force over the beam is 4KN. Propose an alternate rectangular section of the same material so that the maximum shear stress developed is same in both sections. Assume then width of the section to be 2/3 of the depth. 2. A beam of uniform section 10 m long carries a udl of 2KN/m for the entire length and a concentrated load of 10 KN at right end. The beam is freely supported at the left end. Find the position of the second support so that the maximum bending moment in the beam is as minimum as possible. Also compute the maximum bending moment 3. A beam of size 150 mm wide, 250 mm deep carries a uniformly distributed load of w kn/m over entire span of 4 m. A concentrated load 1 kn is acting at a distance of 1.2 m from the left support. If the bending stress at a section 1.8 m from the left support is not to exceed 3.25 N/mm 2 find the load w. 4. A cantilever of 2m length carries a point load of 20 KN at 0.8 m from the fixed end and another point of 5 KN at the free end. In addition, a u.d.l. of 15 KN/m is spread over the entire length of the cantilever. Draw the S.F.D, and B.M.D. 5. A Simply supported beam of effective span 6 m carries three point loads of 30 KN, 25 KN and 40 KN at 1m, 3m and 4.5m respectively from the left support. Draw the SFD and BMD. Indicating values at salient points. 6. A Simply supported beam of length 6 metres carries a udl of 20KN/m throughout its length and a point of 30 KN at 2 metres from the right support. Draw the shear force and bending moment diagram. Also find the position and magnitude of maximum Bending moment. 7. A Simply supported beam 6 metre span carries udl of 20 KN/m for left half of span and two point loads of 25 KN end 35 KN at 4 m and 5 m from left support. Find maximum SF and BM and their location drawing SF and BM diagrams. 8. A cantilever 1.5m long is loaded with a uniformly distribution load of 2 kn/m run over a length of 1.25m from the free end it also carries a point load of 3kn at a distance of 0.25m from the free end. Draw the shear force and bending moment diagram of the cantilever.

19 9. For the simply supported beam loaded as shown in Fig., draw the shear force diagram and bending moment diagram. Also, obtain the maximum bending moment. 10. A cast iron beam is of T-section as shown in Fig. The beam is simply supported on a span of 6 m. The beam carries a uniformly distributed load of 2kN/m on the entire length (span). Determine the maximum tensile and maximum compressive stress. UNIT III TORSION PART-A (2 Marks) 1. Define torsional rigidity of the solid circular shaft. 2. Distinguish between closed coil helical spring and open coil helical spring. 3. What is meant by composite shaft? 4. What is called Twisting moment? 5. What is Polar Modulus? 6. Define: Torsional rigidity of a shaft. 7. What do mean by strength of a shaft?

20 8. Write down the equation for Wahl factor. 9. Define: Torsional stiffness. 10. What are springs? Name the two important types. 11. How will you find maximum shear stress induced in the wire of a close-coiled helical spring carrying an axial load? 12. Write the expressions for stiffness of a close coiled helical spring. 13. Find the minimum diameter of shaft required to transmit a torque of Nm if the maximum shear stress is not to exceed 45 N/mm Find the torque which a shaft of 50 mm diameter can transmit safely, if the allowable shear stress is 75 N/mm Differentiate open coiled helical spring from the close coiled helical spring and state the type of stress induced in each spring due to an axial load. 16. What is spring index (C)? 17. State any two functions of springs. 18. Write the polar modulus for solid shaft and circular shaft. 19. What are the assumptions made in Torsion equation 20. Write an expression for the angle of twist for a hollow circular shaft with external diameter D, internal diameter d, length l and rigidity modulus G. PART- B (16 Marks) 1. Determine the diameter of a solid shaft which will transmit 300 KN at 250 rpm. The maximum shear stress should not exceed 30 N/mm2 and twist should not be more than 10 in a shaft length 2m. Take modulus of rigidity = 1 x 10 5 N/mm The stiffness of the closed coil helical spring at mean diameter 20 cm is made of 3 cm diameter rod and has 16 turns. A weight of 3 KN is dropped on this spring. Find the height by which the weight should be dropped before striking the spring so that the spring may be compressed by 18 cm. Take C= 8x10 4 N/mm It is required to design a closed coiled helical spring which shall deflect 1mm under an axial load of 100 N at a shear stress of 90 Mpa. The spring is to be made of round wire having shear modulus of 0.8 x 10 5 Mpa. The mean diameter of the coil is 10 times that of the coil wire. Find the diameter and length of the wire. 4. A steel shaft ABCD having a total length of 2400 mm is contributed by three different sections as follows. The portion AB is hollow having outside and inside diameters 80 mm and 50 mm respectively, BC is solid and 80 mm diameter. CD is also solid and 70 mm diameter. If the angle of twist is same for each section, determine the length of each portion and the total angle of twist. Maximum permissible shear stress is 50 Mpa and shear modulus 0.82 x 10 5 MPa.