Section 2 Flashcards
Two-dimensional stream function
A.relates velocity and pressure.
B.is constant along a stream line.
C.is constant along an equipotential surface.
D.none of these.
B. is constant along a stream line.
A hydraulic ram acts as a/an __________ pump.
A.centrifugal
B.reciprocating
C.impulse
D.parallel cylinder
C. impulse
What causes cavitation in centrifugal pump ?
A.High suction pressure
B.Low barometric pressure
C.Low suction pressure
D.High suction velocity
C. Low suction pressure
Draining of shallow pits or sump is done by a sump pump, which is a __________ pump.
A.single stage vertical
B.centrifugal
C.plunger
D.diffuser
A. single stage vertical
The ratio of average fluid velocity to the maximum velocity in case of laminar flow of a Newtonion fluid in a circular pipe is
A.0.5
B.1
C.2
D.0.66
A. 0.5
Choose the correct set of dimensions of viscosity that are equivalent (where, F, M, L, T are dimensions for force, mass, length and time respectively).
A.FL^-2 T, ML^-1 T^-1
B.FLT, ML^-1 T^-1
C.ML^-1 T^-3, F^-1 L^2 T
D.F^-1 L^2 T^-1, MLT^-3
A.FL^-2 T, ML^-1 T^-1
The line of action of the buoyant force passes through the centre of gravity of the
A.submerged body.
B.displaced volume of the fluid.
C.volume of fluid vertically above the body.
D.horizontal projection of the body.
B. displaced volume of the fluid.
The friction factor for turbulent flow in a hydraulically smooth pipe
A.depends only on Reynolds number.
B.does not depend on Reynolds number.
C.depends on the roughness.
D.none of these.
A. depends only on Reynolds number.
The pressure at a point in a fluid is not the same in all directions, when the fluid is viscous and
A.moving
B.static
C.cold
D.hot
A. moving
What causes convective acceleration in fluid flow ?
A.Steep slope in flow
B.Unsteady nature of flow
C.Non-uniformity of flow
D.Turbulence in flow
C. Non-uniformity of flow
The Stoke’s stream function applies to the
A.irrotational flow only.
B.ideal/non-viscous fluids only.
C.cases of axial symmetry.
D.none of these.
C. cases of axial symmetry.
Slugging in a fluidised bed can be avoided by using
A.tall narrow vessel.
B.deep bed of solids.
C.shallow beds of solids and proper choice of particle size. D.very large particles.
C. shallow beds of solids and proper choice of particle size.
The ratio of width to depth for the most economical rectangular section in open channel flow is
A.0.5
B.1
C.1.5
D.2
D. 2
The simple pitot tube measures the __________ pressure.
A.static
B.dynamic
C.total
D.none of these
C. total
Capacity of a hydraulic accumulator is defined in terms of maximum
A.amount of energy stored.
B.flow rate through accumulator.
C.rate of falling of ram.
D.volume available in the cylinder.
A. amount of energy stored.
Boundary layer separation is characterised by one of the conditions given below, where ‘Re’ is the Reynolds number for the flow. Select the appropriate conditions.
A.Re «_space;1, accelerating flow
B.Re»_space; 1, accelerating flow
C.Re «_space;1, decelerating flow
D.Re»_space;1, decelerating flow
D. Re»_space;1, decelerating flow
Manometers measure the __________ pressure.
A.vacuum as well as the atmospheric
B.difference in
C.absolute
D.gage
B. difference in
Which of the following fluid forces are not considered in the Navier-Stoke’s equation?
A.Gravity forces
B.Viscous forces
C.Pressure forces
D.Turbulent forces
D. Turbulent forces
In turbulent flow, a rough pipe has the same friction factor as a smooth pipe
A.in the zone of complete turbulence.
B.when the roughness projections are much smaller than the thickness of the laminar film.
C.everywhere in the transition zone.
D.when the friction factor is independent of the Reynold’s number.
B. when the roughness projections are much smaller than the thickness of the laminar film.
Air vessel provided in a reciprocating pump
A.smoothens the flow by avoiding pulsations.
B.increases the volumetric efficiency of the pump.
C.saves the pump from the danger of cavitation.
D.none of these.
D. none of these.
Bernoulli’s equation is dependent on the
A.first law of thermodynamics.
B.third law of thermodynamics.
C.law of conservation of momentum.
D.none of these.
D. none of these.
The capacity of an accumulator is the maximum
A.energy which it can store.
B.discharge which it can deliver.
C.liquid which it can store.
D.none of these.
A. energy which it can store.
With increase in the temperature, viscosity of a liquid
A.increases
B.decreases
C.remains constant
D.may increase or decrease; depends on the liquid
B. decreases
Vena-contracta pressure tapping is at a distance __________ from the position of an orificemeter fitted in a pipe of internal diameter ‘d’
A.d
B.0.5 d
C.2d
D.4d
B. 0.5 d
The pump impeller and the turbine runner in a hydraulic torque converter
A.have the same diameter.
B.have different diameters.
C.are directly coupled.
D.none of these.
B. have different diameters.
Reciprocating pumps compared to centrifugal pumps
A.deliver liquid at uniform pressure.
B.can handle slurries more efficiently.
C.are not subject to air binding.
D.can be operated with delivery valve closed.
C. are not subject to air binding.
The fluid property which matters for fall-ing rain drops to acquire spherical shape is its
A.pressure
B.height of descend
C.viscosity
D.surface tension
D. surface tension
- The simple pitot tube does not measure the
A.static pressure.
B.dynamic pressure.
C.velocity at the stagnation point.
D.all (a), (b) and (c).
D. all (a), (b) and (c).
Boundary layer separation occurs when the
A.pressure reaches a minimum. B.cross-section of the channel is reduced.
C.valve is closed in a pipeline.
D.velocity of sound is reached.
B. cross-section of the channel is reduced.
The head loss in turbulent flow in a pipe varies
A.directly as the velocity.
B.inversely as the square of the velocity.
C.approximately as the square of the velocity.
D.inversely as the square of the diameter.
C. approximately as the square of the velocity.
For flow through an orifice from a reservoir, the actual velocity at the vena con-tracta is given by
A.2gh
B.C.V. 2gh
C.Cd 2gh
D.Cc 2gh
B.C.V. 2gh
The ratio of the hydraulic radius to the diameter of the channel, for maximum mean velocity of flow in a circular channel, in open channel flow is
A.0.3
B.0.9
C.0.03
D.0.66
A. 0.3
- For the free settling of a spherical particle through a fluid, the slope of, CD- log NRe , plot is
A.1
B.-1
C.0.5
D.-0.5
B. -1
A centrifugal pump loses prime after starting. The reason of this trouble may be
A.incomplete priming.
B.too high a suction lift.
C.low available NPSH and air leaks in the suction pipe.
D.all (a), (b), and (c).
D. all (a), (b), and (c).
Venturimeter and orificemeter measures the __________ of the fluid.
A.pressure
B.maximum velocity
C.average velocity
D.point velocity
C. average velocity
Surge tanks are provided in high pressure water pipelines to
A.store a definte quantity ofwater all the time,
B.reduce the water hammer.
C.facilitate easy dismantling of pipeline for cleaning and maintenance.
D.none of these.
B. reduce the water hammer.
Working principle of manometer comprises of balancing a coloumn of liquid against the pressure to be measured. Inclined tube manometer is especially used for the measurement of __________ pressure.
A. small differential
B. atmospheric
C. absolute
D. gage
A. small differential
Isotropic turbulence occurs
A. where there is no velocity gradient.
B. at higher temperatures.
C. only in Newtonion fluids.
D. none of these.
A. where there is no velocity gradient.
Euler’s equation of motion states, that at every point, the
A.fluid momentum is constant.
B.force per unit mass equals acceleration.
C.rate of mass outflow is equal to the rate of mass inflow.
D.none of these.
B. force per unit mass equals acceleration.
The co-efficient of drag and lift for an incompressible fluid depends on the
A.Reynolds number
B.Froude number
C.Mach number
D.all (a), (b) and (c)
A. Reynolds number
Hydraulic intensifier is used for increasing the
A. rate of velocity of liquid supply.
B. rate of flow through delivery pipeline of a pump.
C. intensity of pressure of the liquid.
D. momentum rate through delivery pipe.
C. intensity of pressure of the liquid.
Hydrometer measures the specific gravity of liquids based on the principles of buoyancy. Pycnometer is used to measure the specific gravity of
A. powder & grannular solids
B. liquids
C. low melting point semi-solids
D. all ‘a’, ‘b’ & ‘c’
D. all ‘a’, ‘b’ & ‘c’
Euler’s equation of motion is a statement expressing
A. conservation of mass.
B. conservation of energy.
C. Newton’s first law of motion.
D. Newton’s second law of motion.
A. conservation of mass.
During ageing of fluid carrying pipes, the
A. pipe becomes smoother with use.
B. friction factor increases linearly with time.
C. absolute roughness decreases with time.
D. absolute roughness increases linearly with time.
D. absolute roughness increases linearly with time.
Which of the following may be termed as a variable orifice flowmeter ?
A.Rotameter
B.Pitot tube
C.V-notch
D.All (a), (b) and (c)
A. Rotameter
