Download GTU (Gujarat Technological University Ahmedabad) B.Tech/BE (Bachelor of Technology/ Bachelor of Engineering) 2020 Summer 6th Sem 2160602 Applied Fluid Mechanics Previous Question Paper

Enrolment No.___________

**GUJARAT TECHNOLOGICAL UNIVERSITY**

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

**Subject Code: 2160602**

**Date:27/10/2020**

**Subject Name: APPLIED FLUID MECHANICS**

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

**Total Marks: 70**

**Instructions:**

**1. Attempt all questions.**

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

3. Draw sketch wherever necessary

3. Draw sketch wherever necessary

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

**Q.1**

**(a)**Determine the dimensions of : dynamic viscosity, torque and angular velocity

**03**

**(b)**Enlist the forces acting on fluied in motion

**04**

**(c)**Explain with diagrams how the main charecteristic curves for pumps are obtained

**07**

and how they are useful in pump selection.

**Q.2**

**(a)**Define : eddy viscosity, prandattl's mixing length, and shear velocity

**03**

**(b)**Give reasons why the expansion transition length in pipes are kept greater in

**04**

comparison to contraction transition length.

**(c)**Expalin the Reynolds experiment for pipe flow with the help of sketch of the

**07**

experimental set up and graph between head loss and Reynolds Number

**OR**

**(c)**Explain with diagram the specific energy curve for different discahrges and develop

**07**

the expression for the minimum specific energy and state the charecteristics of flow

in the critical state.

**Q.3**

**(a)**Differentiate between drawdown and back water curve of GVF giving examples

**03**

where they occur

**(b)**Discuss the utility of hydraulic jump

**04**

**(c)**A partially open sluice gate discharges water at 10 m/s with a depth of 50 cm in the

**07**

horizontal rectnagular channel of width 10 meter.Find the pre hydraulic jmp Froude

number and the height of the hydraulic jump that will occur under the given

conditions.

**OR**

**Q.3**

**(a)**State the assumptions made in the development of dynamic equation of gradually

**03**

varied flow.

**(b)**.Develop the relationship between Maning's "n" and Chezy's "C" used for uniform

**04**

steady flow

**(c)**Calculate the

specific energy, critical depth and velocity for the flow of 10 m3/s in a

**07**

lined rectangular channel 2.5 meter wide with 2m depth of water. Find whether the

flow is in sub critical or super critical state.

**Q.4**

**(a)**Define developing and developed flow

**03**

**(b)**Explain why the development length for turbulent flow is much less compared to the

**04**

development length required for a laminar flow.

**(c)**With the help of neat sketch describe the development of bounday layer over a flat

**07**

plate.

**OR**

**Q.4**

**(a)**Define and expalin the significance of laminar sub layer

**03**

**(b)**Define the concept of displacement thickness and develop an expression for the

**04**

same.

1

**(c)**Discuss the means of separation control for flow past an aerofoil, around a pipe bend

**07**

and flow around a sphere

**Q.5**

**(a)**Explain the principle of dimensional homogenity. Give an example each of

**03**

dimensionally homogeneous and non homogeneous equation.

**(b)**Define distotrted and undistorted models and give their utility

**04**

**(c)**A 10 cm diameter plate is to be rotated in water and a 25 cm diameter plate is to be

**07**

rotated in air under dynamically similar conditions. Find the ratios of the torques

required given that mass density of water and air respectively are 1000 kg/ m3 / and

1.2 kg /m3, dynamic viscosity of water and air are 0.001 Ns/m2 and 1.8x 10-6 Ns/m2

respectively.

**OR**

**Q.5**

**(a)**Discuss the circumstances under which the pumps will be connected in series or

**03**

parallel. Explain the resultant head and discahrges in the two cases

**(b)**Explain the scale effect in models

**04**

**(c)**In a 1:20 model of a stilling basin the height of the hydraulic jump and the energy

**07**

dissipated in the model is 0.2 meter and 0.1 kilowatt respectively, find the

corresponding values in the prototype.

.

.

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This post was last modified on 04 March 2021