Hydraulic accumulator is used for____________________?
(A) accumulating oil
(B) supplying large quantities of oil for very short duration
(C) generally high pressures to operate hydraulic machines
(D) supplying energy when main supply fails
(D) accumulating hydraulic energy
A hydraulic intensifier normally consists of __________________?
(A) two cylinders, two rams and a storage device
(B) a cylinder and a ram
(C) two co-axial rams and two cylinders
(D) a cylinder, a piston, storage tank and control valve
(D) special type of pump with storage device and a pressure regulator
Maximum impulse will be developed in hydraulic ram when ___________________?
(A) waste valve closes suddenly
(B) supply pipe is long
(C) supply pipe is short
(D) ram chamber is large
(D) supply pipe has critical diameter
According to fan laws, at constant speed and capacity, the pressure and power vary_____________________?
(A) directly as the air or gas density
(B) inversely as square root of density
(C) inversely as density
(D) as square of density
(D) as square root of density
Impulse turbine is generally fitted______________________?
(A) at the level of tail race
(B) little above the tail race
(C) slightly below the tail race
(D) about 2.5 m above the tail race to avoid cavitation
(D) about 2.5 m below the tail race to avoid cavitation
Francis turbine is best suited for_____________________?
(A) medium head application from 24 to 180 m
(B) low head installation up to 30 m
(C) high head installation above 180 m
(D) all types of heads
(D) none of the above
Francis, Kaplan and propeller turbines fall under the category of___________________?
(A) Impulse turbines
(B) Reaction turbines
(C) Axial flow turbines
(D) Mixed flow turbines
(D) Reaction-cum-impulse turbines
The discharge through a reaction turbine with increase in unit speed____________________?
(A) increases
(B) decreases
(C) remains unaffected
(D) first increases and then decreases
(D) first decreases and then increases
Specific speed for reaction turbines ranges from___________________?
(A) 0 to 4.5
(B) 10 to 100
(C) 80 to 200
(D) 250 to 300
(D) none of the above
Which place in hydraulic turbine is most susceptible for cavitation __________________?
(A) inlet of draft rube
(B) blade inlet
(C) guide blade
(D) penstock
(D) draft tube exit