Download GTU (Gujarat Technological University Ahmedabad) B.Tech/BE (Bachelor of Technology/ Bachelor of Engineering) 2020 Winter 7th Sem 2170106 Boundary Layer Theory Previous Question Paper
Enrolment No.___________
GUJARAT TECHNOLOGICAL UNIVERSITY
BE- SEMESTER?VII (NEW) EXAMINATION ? WINTER 2020
Subject Code:2170106 Date:28/01/2021
Subject Name:Boundary Layer Theory
Time:10:30 AM TO 12:30 PM Total Marks: 56
Instructions:
1. Attempt any FOUR questions out of EIGHT questions.
2. Make suitable assumptions wherever necessary.
3. Figures to the right indicate full marks.
Q.1
(a) Draw a path lines for laminar and turbulent flows.
03
(b) Draw a profile transition from laminar to turbulent flow.
04
(c) List out different types of wind tunnel and draw open
07
type subsonic windtunnel
Q.2
(a) Write characteristics of Laminar flow.
03
(b) Write characteristics of Turbulent flow.
04
(c) Derive Couette flow equation with neat sketch.
07
Q.3
(a) Define Laminar Sublayer.
03
(b) What is Boundary layer control?
04
(c) Derive orr-sommer field equation.
07
Q.4
(a) Define Displacement thickness with sketch.
03
(b) Define momentum thickness and Energy thickness.
04
(c) Derive an expression for the Darcy weisbach equation for
07
turbulent boundary layer flow
Q.5
(a) Explain flow over a flat plate for Turbulent flow.
03
(b) Explain thermal boundary layer growth over the hot
04
surface.
(c) Draw an effect of viscosity on an airfoil in a moving
07
fluid.
Q.6
(a) Explain Reynolds analogy.
03
(b) Determine the wall shearing stress in a pipe of diameter
04
100mm which carries water. The velocities at the pipe
centre and 30mm from the pipe centre are 2 m/s and 1.5
m/s respectively. The flow in pipe is given as Turbulent
(c) Derive Momentum equations for boundary layer by von
07
karman
Q.7
(a) Define critical Reynolds number.
03
(b) What is Prandtl mixing length theory?
04
(c) Derive governing equation for Turbulent flow.
07
Q.8
(a) Explain flow over a Cylinder for Laminar flow.
03
1
(b) A thin plate is moving in still atmospheric air at a
04
velocity of 5m/s. The length of the plate is 0.6 m and
width 0.5m.
Calculate 1. The thickness of the B.L at the end of the
Plate
2. Drag force on one side of the plate
Take Density of air as 1.24 kg/m3
Kinematic viscosity 0.15 stokes
(c) Derive velocity distribution for turbulent flow in smooth
07
pipe.
2
This post was last modified on 04 March 2021