PTU Punjab Technical University B-Tech May 2019 Question Papers 4th Semester Civil Engineering (CIV)
Total No. of Pages : 02
Total No. of Questions : 09
B.Tech.(CE) (2011 Onwards) (Sem.?4)
FLUID MECHANICS-II
Subject Code : BTCE-404
M.Code : 56086
Time : 3 Hrs. Max. Marks : 60
INSTRUCTION TO CANDIDATES :
1.
SECTION-A is COMPULSORY consisting of TEN questions carrying T WO marks
each.
2.
SECTION-B contains FIVE questions carrying FIVE marks each and students
have to attempt any FOUR questions.
3.
SECTION-C contains T HREE questions carrying T EN marks each and students
have to attempt any T WO questions.
SECTION-A
1.
Answer briefly :
a) What do you mean by stoke's law in Laminar flow?
b) What are the ranges of Reynolds number for the flow in the boundary layer to be
laminar or turbulent?
c) On what factors does the upper limit of Reynolds number depends upon.
d) Define critical velocity and critical Reynolds number.
e) Mention any two methods for preventing the separation of boundary layer.
f) What do you mean by the gradually varied flow?
g) State Kuttar's formulae for determining the constant C.
h) In rectangular open channel flow, what is the ratio of critical depth to its specific
energy?
i) What are draw down curves?
j) What is the difference between Hydraulic jump and surge?
1 | M Code 56086 (S2)-1093
SECTION-B
2.
Give classification of surface profiles.
3.
A 3.6m wide rectangular channel carries water to a depth of 1.8m. In order to measure
the discharge, the channel width is reduced to 2.4m and a hump of 0.3m height is
provided in the bottom. Calculate the discharge if water surface in the contracted section
drops by 0.15m. Assume no losses.
4.
Explain why drag coefficient and hence drag of a sphere in subsonic flow is suddenly
decreased as the flow velocities are increased beyond a certain point.
5.
Explain different types of hydraulic jumps along with neat sketches.
6.
Prove that for hydraulically most efficient rectangular channel, the width should be two
times the depth of flow, so that the hydraulic radius is equal to half the depth of flow.
SECTION-C
7.
What conditions are necessary for formation of a hydraulic jump? What are the elements
and characteristics of hydraulic jump?
8.
The normal depth of flow of water, in a rectangular channel 1.5m wide, is 1m. The bed
slope of the channel is 0.0006 and Manning's roughness coefficient n=0.012. Find the
critical depth. At a certain section of the same channel the depth is 0.92m while at a
second section the depth is 0.86m. Find the distance between the two sections (use one
reach in the calculations). Also find whether the section is located downstream or
upstream with respect to the first section.
9.
A hydraulically efficient trapezoidal channel has side slopes of 1:1. It is required to
discharge 14m3/s with a gradient (channel slope) of 1 in 1000. If unlined, the value of
Chezy's C is 45. If lined with concrete, the value is 70. If the cost per m3 of excavation is
three times the cost per m3 of lining, will the lined or unlined channel be cheaper.
NOTE : Disclosure of Identity by writing Mobile No. or Making of passing request on any
page of Answer Sheet will lead to UMC against the Student.
2 | M Code 56086 (S2)-1093
This post was last modified on 04 November 2019