Download GTU (Gujarat Technological University Ahmedabad) B.Tech/BE (Bachelor of Technology/ Bachelor of Engineering) 2020 Summer 4th Sem 3140611 Fluid Mechanics And Hydraulics Previous Question Paper

Enrolment No.___________

**GUJARAT TECHNOLOGICAL UNIVERSITY**

**BE - SEMESTER? IV EXAMINATION ? SUMMER 2020**

**Subject Code: 3140611**

**Date:04/11/2020**

**Subject Name: Fluid Mechanics & Hydraulics**

**Time: 10:30 AM TO 01:00 PM**

**Total Marks: 70**

**Instructions:**

**1. Attempt all questions.**

**2. Make suitable assumptions wherever necessary.**

**3. Figures to the right indicate full marks.**

**Q.1 (a)**Define density, specific volume & surface tension.

**03**

**(b)**The velocity distribution for flow over a flat plate is given by

**04**

u = 0.75 y - y2 in which u is the velocity in metre per second at a

distance y metre above the plate. Determine the shear stress at

y = 0.20 m. Take dynamic viscosity of fluid as 8.0 poise.

**(c)**u=

Ex 3/4

plain the phenomenon of capillarity.Obtain an expression for

**07**

capillary rise of a liquid.

**Q.2 (a)**Define atmospheric, absolute & vaccum pressure.

**03**

**(b)**Explain hydrostatic paradox.

**04**

**(c)**Write short note on manometers.

**07**

**OR**

**(c)**State & prove Pascal's law.

**07**

**Q.3 (a)**Define total pressure, centre of pressure & buoyancy.

**03**

**(b)**A rectangular plane surface is immersed vertically in water such that

**04**

its upper edge is touching free surface of liquid. Show that the depth

of centre of pressure is 2

**/**3 d for rectangular surface of width b and

depth d.

**(c)**Define metacentre & metacentric height. How will you determine

**07**

metacentric height of a floating body experimentally? Explain with

neat sketch.

**OR**

**Q.3 (a)**Define stream lines, streak lines & flow net.

**03**

**(b)**Differentiate between (i) Uniform & non uniform flow (ii) Sub

**04**

critical & super critical flow.

**(c)**State & prove Bernoulli's equation & write assumption made for

**07**

such a derivation.

**Q.4 (a)**Define

orifice, mouthpiiece & notches.

**03**

**(b)**Find the discharge of water flowing over a rectangular notch of 2.0

**04**

m length when the constant head over the notch is 500 mm.Take Cd

= 0.62

**(c)**Differrentiate between small & large orifice.Obtain an expression

**07**

for discharge through large orifice.

**OR**

**Q.4 (a)**Define major energy losses in pipe, hydraulic gradient line & total

**03**

energy line.

**(b)**Three pipes of lengths 800 m, 500 m and 400 m and of diameters

**04**

500 mm, 400 mm & 300 mm respectively are connected in series.

These pipes are to be replaced by a single pipe of length 1700 m.

Find the diameter of the single pipe.

**(c)**Define viscous flow. Derive expression for Hagen-Poiseuille's

**07**

formula.

1

**Q.5 (a)**Define turbulent flow in open channel, specific energy curve &

**03**

hydraulic jump.

**(b)**A sluice get discharges water into a horizontal rectangular channel

**04**

with a velocity of 10 m

**/**sec & depth of flow of 1 m.Determine the

depth of flow after the jump & consequent losses in total head.

**(c)**Define gradually varied flow. Derive equation of gradually varied

**07**

flow.

**OR**

**Q.5 (a)**Define dimensional homogeneity, similitude & undistorted models

**03**

**(b)**Explain method of selecting repeating variables.

**04**

**(c)**The pressure difference p in a pipe of diameter D and length l due

**07**

to viscous flow depends on the velocity V, viscosity

*&**density*.

Using Buckingham's theorem obtain an expression for p.

2

This post was last modified on 04 March 2021