Subject 2014 Question Paper — Government College of Engineering and T…

The 2014 Subject previous year question paper (Government College of Engineering and Technology, Jammu), with every question and its marks.

Instructions

Q1. (a) A two dimensional flow is described by the velocity component: $u = 5x^3$ and $v = -15x^2y$. Evaluate the steam function, velocity and acceleration at point $P(x=1m$ and $y=2m)$. (b) Explain how you would find the resultant pressure on a curved surface immersed in a liquid? [20 marks]
Q2. (a) A U-tube differential manometer connects two pressure pipe A & B. Pipe A contains carbon tetrachloride have G = 1.6 under a pressure of $1.2\text{ kgf/cm}^2$ and pipe B contains oil of G = 0.8 under a pressure of $2\text{ kgf/cm}^2$. The pipe A lies $2.5\text{ m}$ above pipe B and the mercury level in the limb communicating with pipe A lies $4\text{ m}$ below the pipe A. Find the difference in the levels of mercury in the two limbs. (b) Define the following: (a) Vorticity (b) Velocity potential function (c) Capillarity (d) Stream function (e) Stream line (f) Streak line [20 marks]

Q3. (a) Differentiate between broad crested weir and narrow crested weir. Find the condition for maximum discharge over a broad - crested weir. (b) A $30\text{ cm}$ dia pipe supplies water steadily to a turbine at $1.8\text{ bar}$. The water leaves the turbine on exit side through a $60\text{ cm}$ pipe with a pressure of $0.25\text{ bar}$. A vertical distance of $1.5\text{ m}$ separate the centre of pipes at sections where measurements of pressure have been made. Calculate the power delivered to the turbine from water if $0.25\text{ m}^3\text{/s}$ of water passes through the arrangement. Neglect friction losses. [20 marks]
Q4. (a) Starting with Euler's equation of motion along a stream line, obtain Bernoulli's equation by its integration. (b) Find the discharge over a weir $8\text{ m}$ long and $3\text{ m}$ high flowing under a head of $2.4\text{ m}$. The width of the approach channel is $10\text{ m}$. Take Cd to be $0.622$ and assuming the velocity of approach to be negligible. [20 marks]

Q5. (a) What are the methods of dimensional analysis? Describe the Rayleigh's method for dimensional analysis. (b) A $7.5\text{ cm}$ dia jet of water impinges on a series of hemispherical cups and it deflected through $180^0$ as shown in Figure (a). If the velocity of the jet is $30\text{ m/s}$ and that of the cup is $12\text{ m/s}$, find the work done per second by the water striking the cups. [20 marks]

Q6. (a) Explain the terms: distorted models and undistorted models. What is the use of distorted models? (b) The loss of pressure $\Delta p$ for laminar flow in a pipe is a function of pipe length $l$, its diameter $D$, mean velocity $U$, and dynamic viscosity $\mu$. Obtain an expression for the pressure loss. [20 marks]
Q7. (a) Derive an expression for loss of head due to friction in pipe. (b) An old water supply distribution pipe $25\text{ cm}$ dia of a city is to be replaced by two parallel pipes of smaller dia having equal lengths and identical friction factor values. Find out the new dia required. [20 marks]
Q8. (a) With the help of neat sketch, explain the circulation theory of Lift and Magnus effect. (b) Air blows over a cylindrical smoke-stack of $5\text{ cm}$ dia with a velocity of $0.2\text{ m/s}$. Work out the total aerodynamic drag, shear drag and pressure drag on $1\text{ m}$ length of the smoke-stack. For the flow situation, the total and shear drag coefficient are $1.25$ and $0.18$ respectively. [20 marks]