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PSU Solved question papers of Mechanical Engineering There are many PSUs located in India, like: SAIL GAIL BHEl BEL ONGC BARC DMRC MTNL PSUs Mechanical Engineering question paper contains questions from following syllabus: 1. Thermodynamics. Thermodynamics, Cycles and IC Engines, Basic concepts, Open and Closed systems. Heat and work. Zeroth, First and Second Law, Application to non-Flow and Flow processes. Entropy, Availability, Irreversibility and Tds relations. Claperyron and real gas equations, Properties of ideal gases and vapours. Standard vapour, Gas power and Refrigeration cycles. Two stage compressor. C-I and S.I. Engines. Pre-ignition, Detonation and Diesel-knock, Fuel injection and Carburation, Supercharging. Turbo-prop and Rocket engines, Engine Cooling, Emission & Control, Flue gas analysis, Measurement of Calorific values. Conventional and Nuclear fuels, Elements of Nuclear power production. 2. Heat Transfer and Refrigeration and Airconditioning. Heat Transfer and Refrigeration and Airconditioning. Modes of heat transfer. One dimensional steady and unsteady conduction. Composite slab and Equivalent Resistance. Heat dissipation from extended surfaces, Heat exchangers, Overall heat transfer coefficient, Empirical correlations for heat transfer in laminar and turbulent flows and for free and forced Convection, Thermal boundary layer over a flat plate. Fundamentals of diffusive and connective mass transfer, Black body and basic concepts in Radiation, Enclosure theory, Shape factor, Net work analysis. Heat pump and Refrigeration cycles and systems, Refrigerants. Condensers, Evaporates and Expansion devices, Psychrometry, Charts and application to air conditioning, Sensible heating and cooling, Effective temperature, comfort indices, Load calculations, Solar refrigeration, controls, Duct design. 3. Fluid Mechanics. Properties and classification of fluids, Manometry, forces on immersed surfaces, Center of pressure, Buoyancy, Elements of stability of floating bodies. Kinematics and Dynamics. Irrotational and incompressible. Inviscid flow. Velocity potential, Pressure field and Forces on immersed bodies. Bernoulli's equation, Fully developed flow through pipes, Pressure drop calculations, Measurement of flow rate and Pressure drop. Elements of boundary layer theory, Integral approach, Laminar and tubulent flows, Separations. Flow over weirs and notches. Open channel flow, Hydraulic jump. Dimensionless numbers, Dimensional analysis, Similitude and modelling. One-dimensional isentropic flow, Normal shock wave, Flow through convergent - divergent ducts, Oblique shock-wave, Rayleigh and Fanno lines. 4. Fluid Machinery and Steam Generators. Performance, Operation and control of hydraulic Pump and impulse and reaction Turbines, Specific speed, Classification. Energy transfer, Coupling, Power transmission, Steam generators Fire-tube and water-tube boilers. Flow of steam through Nozzles and Diffusers, Wetness and condensation. Various types of steam and gas Turbines, Velocity diagrams. Partial admission. Reciprocating, Centrifugal and axial flow Compressors, Multistage compression, role of Mach Number, Reheat, Regeneration, Efficiency, Governance. 5. THEORY OF MACHINES: Kinematic and dynamic analysis of planer mechanisms. Cams. Gears and gear trains. Flywheels. Governors. Balancing of rigid rotors and field balancing. Balancing of single and multicylinder engines, Linear vibration analysis of mechanical systems. Critical speeds and whirling of shafts Automatic controls. 6. MACHINE DESIGN : Design of Joints : cotters, keys, splines, welded joints, threaded fasteners, joints formed by interference fits. Design of friction drives : couplings and clutches, belt and chain drives, power screws. Design of Power transmission systems : gears and gear drives shaft and axle, wire ropes. Design of bearings : hydrodynamics bearings and rolling element bearings. 7. STRENGTH OF MATERIALS Stress and strain in two dimensions, Principal stresses and strains, Mohr's construction, linear elastic materials, isotropy and anisotropy, stress-strain relations, uniaxial loading, thermal stresses. Beams : Bending moment and shear force diagram, bending stresses and deflection of beams. Shear stress distribution. Torsion of shafts, helical springs. Combined stresses, thick-and thin-walled pressure vessels. Struts and columns. Strain energy concepts and theories of failure. 8. ENGINEERING MATERIALS : Basic concepts on structure of solids. Crystalline maferials. Detects in crystalline materials. Alloys and binary phase diagrams. Structure and properties of common engineering materials. Heat treatment of steels. Plastics, Ceramics and composite materials. Common applications of various materials. 9. PRODUCTION ENGINEERING : Metal Forming : Basic Principles of forging, drawing and extrusion; High energy rate forming; Powder metallurgy. Metal Casting : Die casting, investment casting, Shall Moulding, Centrifugal Casting, Gating & Riser design; melting furnaces. Fabrication Processes : Principles of Gas, Arc, Shielded arc Welding; Advanced Welding Processes, Weldability: Metallurgy of Welding. Metal Cutting : Turning, Methods of Screw Production, Drilling, Boring, Milling, Gear Manufacturing, Production of flat surfaces, Grinding & Finishing Processes. Computer Controlled Manufacturing Systems-CNC, DNC, FMS, Automation and Robotics. Cutting Tools Materials, Tool Geometry, Mechanism of Tool Wear, Tool Life & Machinability; Measurement of cutting forces. Economicsof Machining. Unconventional Machining Processes. Jigs and Fixtures. Fits and tolerances, Measurement of surface texture, Comparators Alignment tests and reconditioning of Machine Tools. 10. INDUSTRIAL ENGINEERING : Production Planning and Control : Forecasting - Moving average, exponential smoothing, Operations, scheduling; assembly line balancing, Product development, Break-even analysis, Capacity planning, PERT and CPM. Control Operations : Inventory control ABC analysis, EOQ model, Materials requirement planning. Job design, Job standards, Work measurement, Quality Management - Quality analysis and control. Operations Research : Linear Programming - Graphical and Simplex methods, Transportation and assignment models. Single server queueing model. Value Engineering : Value analysis for cost/value. 11. ELEMENTS OF COMPUTATION : Computer Organisation, Flow charting, Features of Common computer Languages - FORTRAN, d Base III, Lotus 1-2-3, C and elementary Programming. Questions; 1)Unit of Entropy (J/kg K or kJ/kg K) 2)A mass of 100kg is falling from a height of 1 m and penetrates the sand into for 1 m. What is the resistance force given by sand. 3)Ratio of specific heats of air. (1.41) 4)A body weighs 3 kg in air. If it is submerged in a liquid, it weighs 2.5 kg. What is the specific gravity of the liquid. 5)Two cars travell in same direction at 40 km/hr at a regular distance. A car comes in a opposite direction in 60km/hr. It meets each car in a gap of 8 seconds. What is the distance between them? 6)A simple problem involing in hoops stress. For sphere: M= [3/2]*p*V*[density of pressure vessel material/Maximum working stress it can tolerate] For Thin walled pressure walls: Hoops stress or stress in the radial direction =p*r/2t 7)A problem in force calculation in a body moving in a inclined surface. 8)Composition of bronze. (Copper+zinc) 9)Compostion of stainless steel.(iron+chromium+nickel+carbon) 10)CI is manifactured in which process. (cupola process) 11)What percentage of carbon is preset in pig iron. (4.5 to 6%) 12)Water is available at 10m height. What is the pressure available? (pressure=density*g*height; p=1000*9.81*10; p=98100N/m2) 13)What will happen if the speed of the centrifugal pump doubles. 14)The unit eV is widely used in ? (Nuclear and atomic physics) 15)What will happen to the resistance, when the diameter of the conductor is doubled? 16)The power comsumed by a electrical device is 1000W at 250V, What is the resistance in the device? (Power= Voltage*current; Current=Power/Voltage, Current,I=1000/250=4 amps. V=IR, Therefore R=250/4=62.5 ohms) 17)Why DC current is not used in transformer. 18)On what principle the sonar/ radar works? 19)Bending moment diagram for the UDL is in what shape? 20)Function of the distributor in petrol vehicles? (Spark timing) 21)Which is not present in CI engines? (carburrettor) 22)What will happen if one cylinder recieves more amount of fuel spray from injectors than other injectors? 23)Purpose of draft tube in hydraulic turbines? (The purpose of a draft tube is toconvert some of the kinetic energy of the flow from the runner (the rotating part of the turbine) intopressure energy and thereby increase the efficiency ofthe hydro power turbine.) 24)What is the effect or reheater in the gas turbine? (The advantage of reheater is significantly increased thrust; the disadvantage is it has very high fuel consumption and inefficiency) 25)Problems involving with fricition coefficient. 26)Factor of safety = Yeild stress/Working stress. 27)Which is the example of non parallel power transmission (Universal coupling) 28)For perpendicular shafts worm gear is used. 29)A planet gear with 25 teeth is meshed with a sun gear of 100 teeth. Both are connected using a arm. How many rotations are needed for planet gear to complete one rotation around the sun gear? 30)What is equivalent spring constant for spring in parallel? 31) Some questions was asked related to boundry layer and vortex flow. 32) 5 questions were asked in PERT, Process planning, Product planning, Break even analysis. 33)How are tungsten and sintered composite materials are machined? (Electro Discharge Machining, EDM) Yes sure, here I am uploading a pdf file having the PSU Solved question papers of Mechanical Engineering. You can use this question paper in your studies and it will give you basic idea about the examination. This is the content of attachment: 1 The ultimate tensile strength and yield strength of most of the metals, when temperature falls from 0 to - 1 5 0 ~ ~ will (a) Increase (b) Decrease (c) Remain same (d) First increase and then decrease 2. "Troosite" is obtained when (a) Quenching steel during transformation (b) A fully hardened steel is finally drawn at about 677 C (c) Steel is rapidly quenched in oil (d) When alloy steels are rapidly quenched in water 3. Induction hardening is the process of (a) Hardening the core (c) Selective hardening (b) Uniform hardening (d) Hardening surface for wear resistance 4. Heavy water is used in atomic power plants as (a) Fuel (b) Source of energy (c) Lubricant (d) Moderator 5. Which one is not the purpose of heat treatment of steels? (a) Changing the composition of steel on the surface (b) Changing the percentage of carbon and Si in the bulk (c) Increasing or decreasing the grain size (d) Removing undesirable residual stresses a 4. A cold chisel is made of (a) Mild steel (b) Cast iron (c) H.S.S. (d) High carbon 7. A body which is permanently deformed is said to have undergone (a) Elastic deformation (c) Plastic deformation (b) Limit of elastic deformation (d) Uniform deformation 8. The defect responsible for the phenomena of slip, by which most metals deform plastically, is known as (a) Fracture (b) Twinning (c) Dislocation (d) Strain hardening 9. With a punch for which the maximum crushing stress is 4 times the maximum shearing stress of the plate, the biggest hole that can be punched in the plate would be of diameter equal to 1(a) - x Thickness of plate 4 1 (b) 7 x Thickness of plate (c) Plate thickness (d) 2 x plate thickness 10. For traction applications, the type of motor best suited is (a) Induction motor (b) Synchronous motor (c) DC shunt motor (d) DC series motor Remaining questions are in the attachment, please click on it……. Last edited by Aakashd; December 24th, 2019 at 02:35 PM. |