Downloaded From JNTU World. B.Tech II Year II Semester (R09) Regular & Supplementary Examinations June 2014

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1 Downloaded From Code: 9A01404 FLUID MECHANICS AND HYDRAULIC MACHINERY 1 (a) State Newton s law of viscosity. Classify fluids based on Newton s law. What is the effect of (b) temperature on viscosity of water and that of air? Calculate capillary rise in a glass tube of 3 mm diameter when imme sed in water. Take surface tension for water as N/m. Find the percentage inc ease in capi a y ise if the diameter of glass tube is 2 mm. 2 (a) Define streak line, path line, stream line, equi-potential line. (b) Obtain Euler s equation of motion along a stream line and hence derive Bern ulli s equation for steady incompressible fluid flow. (c) Define potential function. If a given incompressible fluid fl w find corresponding stream function. 3 (a) Explain briefly: (i) Hydraulic gradient line. (ii) Equivalent pipe. (b) A venturimeter is installed in a pipe line of 300 mm diameter. The throat pipe diameter ratio is 1/3. Water flows through the installation. The pressure in the pipe line is Pa and vacuum in throat is 375 mm of mercury. If 4% of the differential head is lost between the gauges, find the rate of flow through the pipe. 4 (a) Derive the equation between the angle, through which a hinged plate will swing in terms of force of jet and weight of the plate. (b) A 25 mm diameter jet exerts a force of 1 kn in the direction of flow against a flat plate, which is held at an angle of 30 with the axis of the stream. Find the rate of flow. 5 (a) List the elements of a hydroelectric power plant. What is meant by pumped storage plant? (b) How mass curve is used to estimate power generated? 6 (a) Compare impulse and reaction turbines. (b) Design a pelton wheel for a head of 150 meter, power to be developed and speed of the wheel is 360 rpm, coefficient of velocity. Assume other necessary data. 7 (a) Derive an expression for specific speed of a turbine in terms of power P, head H, speed in rpm N. (b) One of the Kaplan turbines installed is rated at 25,000 kw when working under 30 m of head at 180 rpm. Find the diameter of the runner, if overall efficiency of the turbine is Assume flow ratio of 0.65 and diameter of the runner hub equal to 0.3 times the external diameter of runner. Also find specific speed of the turbine. 8 (a) What are the types of reciprocating pumps? (b) A centrifugal pump of 1.5 meter diameter runs at 210 rpm and pumps 180 liters of water per second. The angle which the vane makes at exit with the tangent to the impeller is 25. Assuming radial entry and velocity of flow throughout as 2.5 m/s determine the power required to drive the pump. If manometric efficiency of the pump is 65%, find the average lift of the pump.

2 Downloaded From Code: 9A03401 KINEMATICS OF MACHINERY World Time: 3 hours Max. Marks: 70 1 (a) Explain with the help line diagram the oscillatory cylinder engine mechanism. (b) A crank and slotted leer mechanism used in a shaper has a centre distance f 300 mm between the centre of oscillation of the slotted lever and the cent e f tati n of the crank. The radius of the crank is 120 mm. Find the ratio of the time f cutting to the time of return stroke. 2 (a) Sketch and describe the Hart s straight line mechanism indicating clearly the conditions under which the point P on the corners of the rhombus of the mechanism generates a straight line. (b) Prove geometrically that the above mechanism is capable of producing straight line. 3 What do you mean by Coriolis component of acceleration? When will it exist? Prove that this component of acceleration is equal to 2 x v x ω, where v = linea velocity of the slider along the link and ω = angular velocity of the rotating link. 4 (a) Explain why two Hooke s joints are used to transmit motion from the engine to the differential of an automobile. (b) Two shafts are connected by a universal joint. The driving shaft rotates at a uniform speed of 1500 r.p.m. Determine the greatest permissible angle between the shaft axes so that the total fluctuation of speed does not exceed 100 r.p.m. Also calculate the maximum and minimum speeds of the driven shaft. 5 Derive the expressions for displacement, velocity and acceleration for a circular are cam operating a flat-faced follower: (a) When the contact is on the circular flank. (b) When the contact is on circular nose. 6 (a) Find an expression for the length of the path of contact between two mating spur gears. (b) What do you mean by interference between two mating gears? Explain. 7 A pulley is driven by a flat belt, the angle of lap being 120. The belt is 100 mm wide by 6 mm thick and density 1000 kg/m 3. If the coefficient of friction is 0.3 and the maximum stress in the belt is not to exceed 2 MPa, find the greatest power which the belt can transmit and the corresponding speed of the belt. 8 Explain the working principal of any two of the following with good line diagrams: (a) Differential gears. (b) Reverted gear. (c) Epicyclic gear train.

3 Downloaded From Code: 9A03402 THERMAL ENGINEERING - I Time: 3 hours Max. Ma ks: 70 1 (a) Compare the actual and fuel-air cycles of IC engine. (b) Explain the influence of time loss factor in IC engine. 2 (a) What are the advantages of two-stroke engines over four-stroke engines? (b) Differentiate fuel ignition system and fuel injection system in IC engines and explain fuel injection system in diesel engines. 3 What are the various types of combustion chambers used in SI engines? Explain themjntu briefly. 4 Explain the combustion process in CI engine with the help of block diagram. 5 (a) Define brake power. How do you measure brake power in the laboratory? (b) An oil engine with a clearance volume of 20 % of stroke volume has indicated thermal efficiency of 30.7 %. Find the relative efficiency of the engine. 6 (a) What is under cooling (inter cooling) in case of multistage compression and show the saving of work in p - V and -s diagrams? (b) Differentiate positive displacement and rotodynamic machinery. 7 (a) Explain the principle of operation of centrifugal compressor with the help of neat sketch. (b) Exp ain the variation of pressure and velocity in centrifugal compressor. 8 (a) Define degree of reaction and write the expression for degree of reaction. (b) An axial flow compressor is to have constant axial velocity of 150 m/s and 50% degree of reaction. The mean diameter of blade ring is 35 cm and speed is 15,000 rpm. The exit angles of the blade are 27 o. Calculate blade angle at inlet and work done per kg of air with the help of velocity triangles.

4 Downloaded From Code: 9A03403 MANUFACTURING TECHNOLOGY 1 Explain the following sequential steps related to esign f a gating system. (a) Estimation of optimum pouring time of casting. (b) Calculations of sprue choke area. 2 (a) What precautions should a casting designer take when using cores? (b) Explain the purpose of directional solidification. How it is achieved by using chills? 3 (a) What is the principle of resistance welding? Explain. (b) Explain the resistance spot welding process with sketch. World 4 (a) What are the differences between destructive and non destructive testing methods? (b) What are the advantages and limitations of destructive testing? 5 Write short notes on the following: (a) Theory of rolling. (b) Injection moulding process. 6 (a) Why are multi pass required usually required in wire drawing? (b) What is spring back? Why is it a concern during bending? 7 (a) Explain the various types of extrusion processes with neat sketches. (b) Explain the rotary forging with neat sketches. 8 (a) Explain the principle of USM process with neat diagram. (b) What are the applications of USM? Why can hard materials be cut better by the USM process than soft ones?

5 Downloaded From Code: 9ABS303 ENVIRONMENTAL SCIENCE (Common to CE, ME, IT, CSE, AE, BT & MCT) 1. (a) Highlight the difference between environment science, envi nment studies & environment engineering. (b) Explain environmental science as multidisciplinary science. 2. (a) What is the impact of deforestation on available water res urces? (b) What are the measures adopted to treat waterlogged and saline soils? 3. (a) How energy flows in an ecosystem? Define producer, consumer & decomposers. (b) What are the characteristics feature, structures and function of aquatic ecosystem (ponds & lakes)? 4. Define ecosystem biodiversity. List the hotspots of biodiversity in our country. What is the conservation strategy adopted? 5. (a) What is cyclone? What are the control measures taken for cyclone disaster? (b) What are the causes, effects & control measures for air pollution? 6. (a) What are the water conservation techniques adopted in urban and rural regions? (b) What is the impact of climate change on available water in tropical belt? 7. (a) Explain role of women and child welfare in a nation s development. (b) What is the role of information technology in environmental assessment? 8. (a) Define the following: (i) Food chain. (ii) Food web. (iii) Ecological pyramid. (iv) Acid rain. (b) Short note on: (i) Waste land reclamation. (ii) Effect of ozone layer depletion. (iii) Industrial waste management.

6 Downloaded From Code: 9ABS304 PROBABILITY & STATISTICS (Common to CE, ME, CSS & IT) 1 (a) (b) What is the probability of picking an ace and a king from a 52 cards deck? For any three events A, B and C defined on the sample space S such that B C and P(A) > 0, show that P(B/A) P(C/A). 2 Find a constant b>0 so that the function 3 x e, 0 x b f (x) 4 0, else where is a valid density function 3 In a distribution exactly normal 7% of the items are under 35 and 89% are under 63. What are the mean and standard deviation of the distribution? 4 x is unknown and x 2 1. Find out how large a random Let x be a random variable where 4 sample must be taken in order that the probability will be at least 0.95 and the sample mean x will be with in 0.25 of the population mean? 5 (a) Show that S 2 is an unbiased estimator of the parameter 2. (b) Find 95% confidence limits for the mean of a normally distributed population from which the following sample was taken 15, 17, 10, 18, 16, 9, 7, 11, 13, and (a) Write a note on one tailed test and two tailed test. (b) The mean life time of a sample of 100 light tubes produced by a company is found to be 1560 hours with a population S.D. of 90 hours. Test the hypothesis for = 0.05 that the mean life time of the ight tubes produced by the company is 1580 hours. 7 Given be ow is the number of male births in 1000 families having five children Male children No. of families Test whether the given data is consistent with the hypothesis that the binomial law holds if the chance of a male birth is equal to that of a female birth. 8 (a) Write about (M/M/1) : (N/FIFO) Queuing system. (b) What are the characteristic of (M/M/1) : (N/FIFO) Queuing system?