# UPTU Question papers 2nd year, Hydraulics & Hydraulics machines

B-Tech

(Sem,IV)  Examination, 2006-07

Hydraulics & Hydraulics Machines

Time : 3 Hours                                                                Total marks. 100

Note-   (i)     Attempt all question.

(ii)     Assume suitable data if required. All

1. Attempt any four parts of the following:

a)   Define – Hydraulics mean radius , hydraulics depth, section factor and most efficient channel cross section .

b) On what factor does the Manning’s rugosity  coefficient depends.

c) Show that for a rectangular channel with given area is most efficient when hydraulic radius is half of depth of the flow.

d) Draw velocity distribution diagram in :

(i) Horizontal and vertical section in a rectangular channel.

(ii) Effect of curvature in channel .

e) Obtain formulate for energy correction co-efficient in case of open channel flows.

f) What do you understand by channel of constant velocity . Derive the relevant formulate.

2. . Attempt any two parts of the following :

a) An open channel 3 m wide rectangular in shape carries discharge at normal depth of 1.2 m. What should be slope of channel if the manning’s  ‘n’  is 0.014 ?

b) Prove that the specific energy at critical condition is 1.5 times the critical depth.

c) Draw the specific energy diagram and describe its basic characterics.

d) Difference between sequent depth and alternative depth in an open flow.

e) A wide rectangular channel carries a flow of 2.75 m3/s  per metre width. The depth of flow being  1.5m.  Calculate the rise of the floor level required to produce  a critical flow condition . What is the corresponding fail in surface level.

f) Write an expression for specific force in a rectangular channel and obtain the condition for maximum discharge for a given specific force.

3. . Attempt any four parts of the following :

a) List the assumption made in the derivation of dynamic  equation of gradually varied flow.

b) Prove that the slope of free surface in gradually varied flow in open channel flow is given by:

=

c) Sketch the G.V.F. profiles produced on

(i) Steep slope

(ii) Critical slope

d) A wide rectangular channel 8 m wide is to be laid is to be slope of 1/64 and carries a discharge of 40   m3 /s.  A barrier cross the chainel raises the water surface of 3 m just upstream of the barrier . Find the length of surface profile up to the hydraulic jump upstream. Assume manning’s  rugosity  coif.  As 0.0025

e) Show that the slope of free surface profile can be expressed by.

80 1- (yn/y)3

1- (yc/y)3

Where symbols carry the conventional meaning.

4. Attempt any two parts of the following :

a) Hydraulic jump sometimes used as energy  dissipater at the toy of the  spillway  of a dam. Why? Discuss different ways for obtain the hydraulic jump. Prove that relative hight of the jump, depend only on flow corresponding supercritical condition’s Froude number.

b) Describe axial and mixed and flow pumps. Sketch different characterics curves for centrifugal  pump. How these curve can be used in selecting a pump ?

c) A tidal estuary is flowing at the rate of 1.8 m/s  and depth of flow is 2m. owning to the tide in the sea the level of water rose rapidly and resulting surge took one hour to reach 19.8 km upstream. Compute the hight of the bore above the initial depth of bore.  Also determine the speed and direction of the flow after bore has passed.

5. Attempt any two parts of the following :

a)  Draw neat sketches of various shapes of draft tubes . Also explain the theory of tube.

b)  (i) Define and Explain Hydraulic efficiency mechanical efficiency and overall efficiency in case of turbines. What is the relationship of between these three?

(ii) A peal on wheel develops 4500 kW under a net head of 125 m while running at a speed of 200 rpm.  Assuming Ku  = 0.46 and overall efficiency n0 = 88% the ratio of nozzle die to pitch a circle die

(d/D) = 1/9 determine .   (a) discharge required    ( b) dia of wheel    (c ) the diameter and no. of jebs required .

c) An inward flow reaction turbine discharge readily and the velocity of the flow is constant and equal to the velocity of the discharge from the turbine. Show that hydraulic efficiency is given by