Description : High specific speed of a pump implies that, it is a/an __________ pump. (A) Centrifugal (B) Mixed flow (C) Axial flow (D) None of these
Last Answer : (C) Axial flow
Description : Low specific speed of a pump implies that, it is a/an __________ pump. (A) Axial flow (B) Centrifugal (C) Mixed flow (D) None of these
Last Answer : (B) Centrifugal
Description : A mixed flow centrifugal pump (A) Employs such an impeller, through which the flow is a combination of radial & axial flow (B) Mixes the two fluids before pumping them (C) Pumps the two fluids separately and then mixes them (D) Employs impellers in both the radial & axial directions
Last Answer : (A) Employs such an impeller, through which the flow is a combination of radial & axial flow
Description : A centrifugal pump has the following specifications: Power = 4 H.P.; Speed = 800 rpm Head = 8 metres Flow = 1000 litres/minutes. If its speed is halved, the new discharge will be __________ litres/minute. (A) 500 (B) 200 (C) 1000 (D) 750
Last Answer : (A) 500
Description : Pick up the correct statement from the following regarding radial flow centrifugal pumps: (A) These are provided with volute type or turbine type casings (B) In involute type of radial flow ... centrifugal pump, is always higher than that of volute type (D) All the above
Last Answer : (D) All the above
Description : Pick out the wrong statement pertaining to the turbine agitator. (A) Recommended peripheral speed for the turbine agitator is 200-250 metres/minute (B) Pitched blade turbine agitator gives only radial flow with ... l/4th of agitator diameter (with central disc, it is l/8th of the agitator diameter)
Last Answer : (B) Pitched blade turbine agitator gives only radial flow with complete absence of the axial flow
Description : The specific speed of a centrifugal compressor is generally A. less than that of reciprocating compressor B. independent of compressor type, but depends only on size of compressor C. higher ... axial compressor D. more than specific speed of reciprocating compressor but less than axial compressor
Last Answer : ANSWER : C
Description : Which of the following is most prone to pulsating discharge flow? (A) Centrifugal pump (B) Reciprocating pump (C) Gear pump (D) Axial flow pump
Last Answer : (C) Gear pump
Description : Most commonly used pump for lifting water in water supply mains, is (A) Axial flow pump (B) Reciprocating pump (C) Rotary type pump (D) Centrifugal pumps
Last Answer : (A) Axial flow pump
Description : Conversion of dynamic velocity head into static pressure head in a centrifugal pump is the result of : (a) Increasing area of flow between adjacent vanes from inlet to outlet (b) Difference in pressure between suction and delivery ends (c) Radial thrust in pumps (d) Stuffing Box
Last Answer : (b) Difference in pressure between suction and delivery ends
Description : Propellers are (A) Axial flow mixers (B) Low speed impeller (C) Used for mixing liquids of high viscosity (D) Radial flow mixers
Last Answer : (A) Axial flow mixers
Description : Specific speed of a centrifugal pump depends upon the __________ head. (A) Suction (B) Delivery (C) Manometric (D) None of these
Last Answer : (D) None of these
Description : Consider a centrifugal pump having a specific impeller diameter, fixed impeller speed pumping a liquid of constant density at a particular discharge capacity. With decrease in the capacity of the pump, the __________ decreases. (A) ... the pump (C) Head of the liquid pumped (D) All (A), (B) and (C)
Last Answer : (D) All (A), (B) and (C)
Description : A centrifugal pump has the following specifications: Power = 4 H.P.; Speed = 800 rpm Head = 8 metres Flow = 1000 litres/minutes. If its speed is halved, the power consumed now will be __________ hp. (A) 0.5 (B) 2 (C) 4 (D) 1
Last Answer : (A) 0.5
Description : A centrifugal pump has the following specifications: Power = 4 H.P.; Speed = 800 rpm Head = 8 metres Flow = 1000 litres/minutes. If its speed is halved, then the new head will be __________ metres. (A) 2 (B) 4 (C) 8 (D) 5.5
Last Answer : (A) 2
Description : Specific speed of a centrifugal pump relates it with another pump having the (A) Dynamic similarity (B) Same efficiency (C) Same speed (D) Geometrical similaritySpecific speed of a centrifugal ... another pumphaving the(A) Dynamic similarity(B) Same efficiency(C) Same speed(D) Geometrical similarity
Last Answer : (A) Dynamic similarity
Description : To handle smaller quantity of fluid at higher discharge pressure, use a __________ pump. (A) Reciprocating (B) Centrifugal (C) Volute (D) Rotary vacuum
Last Answer : (A) Reciprocating
Description : Match List-I (Type of Anti-friction bearing) with List-II (Specific Use) and select the using the code given below the Lists: [IES-2006] List-I List -II A. Self-aligning ball bearing 1. For pure axial load B. Taper roller bearing 2. For ... C D (a) 2 1 3 4 (b) 3 4 2 1 (c) 2 4 3 1 (d) 3 1 2 4
Last Answer : (c) 2 4 3 1
Description : Which one of the following type of compressor is mostly used for supercharging of I.C engine A. Radial flow compressor B. Axial flow compressor C. Root blower D. Reciprocating compressor.
Description : In case of a __________ the energy of flow is considerably decreased downstream of the machine. (A) Blower (B) Turbine (C) Centrifugal pump (D) Centrifugal fan
Last Answer : (B) Turbine
Description : Which of the following can be used to create a flow of gas, where no significant compression is required? (A) Reciprocating compressor (B) Blower (C) Axial flow compressor (D) Centrifugal compressor
Last Answer : (B) Blower
Description : In centrifugal pump operation, the cavitation can be eliminated by maintaining suction pressure __________ the vapor pressure of the liquid at the suction temperature. (A) Lower than (B) Higher than (C) Equal to (D) None of these
Last Answer : (B) Higher than
Description : Theoretical head developed by a centrifugal pump does not depend upon the __________ the impeller. (A) Radius of (B) Speed of (C) Fluid velocity leaving (D) None of these
Description : At a constant speed of the centrifugal pump, it’s __________ the impeller diameter. (A) Capacity varies directly with (B) Head varies as the square of (C) Horsepower varies as the cube of (D) All (A), (B) and (C)
Description : In case of a centrifugal pump, the theoretical head developed is dependent on the __________ the impeller. (A) Speed of (B) Diameter of (C) Fluid velocity leaving (D) All (A), (B) and (C)
Description : Which one of the following types of compressor is mostly used for supercharging of IC engines? (a) Radial flow compressor (b) Axial flow compressor (c) Root blower (d) Reciprocating compressor
Last Answer : Ans : c
Description : Compressor mostly used for supercharging of IC engine is A. Radial flow compressor B. Axial flow compressor C. Root blower compressor D. Reciprocating compressor
Last Answer : ANSWER : A
Description : A centrifugal filtration unit operating at a rotational speed of w has inner surface of the liquid (density ρL) located at a radial distance R from the axis of rotation. The thickness of the liquid film is δ and no cake is formed. The ... . ρL (C) ½w 2 . δρL (2R + δ) (D) ½w 2 . R . ρL(R + 2δ)
Last Answer : (C) ½w 2 . δρL (2R + δ)
Description : Why the work per kg of air flow in axial flow compressor is less compared to centrifugal compressor for same pressure ratio ?
Last Answer : Isentropic efficiency of axial flow compressor is higher.
Description : Differentiate between : (i) Reciprocating and rotary air compressor (ii) Centrifugal and axial flow compressor
Last Answer : (i) Reciprocating and rotary air compressor: Sr. No. Reciprocating air compressor Rotary air compressor 1 It is having to and fro motion. It is having rotary ... I.C. engine and for refrigerants and industrial gases. Used universally with large gas turbine.
Description : While starting an axial flow pump, its delivery valve should be kept (A) Open (B) Closed (C) Either open or closed (D) None of these
Last Answer : (A) Open
Description : Reciprocating pumps are not able to compete with the centrifugal pump for industrial use, mainly because these pumps have (A) Very low speeds (B) Smaller discharge (C) Higher capital &maintenance cost (D) High vibrations
Last Answer : (C) Higher capital &maintenance cost
Description : Working of a __________ pump characterises mixed flow. (A) Turbine (B) Piston (C) Diaphragm (D) None of these
Last Answer : (A) Turbine
Description : Pick out the wrong statement. (A) The vessel dispersion number (D/UL) for plug flow and mixed flow approaches zero and infinity respectively (B) Space time in a flow reactor is a ... ideal tubular flow reactor, mixing takes place in radial direction and there is no mixing in longitudinal direction
Last Answer : (C) Mixed reactor is always smaller than the plug flow reactor for all positive reaction orders for a particular duty
Description : The type of pump used for the recirculation of molten sodium coolant in liquid metal cooled reactor is a/an __________ pump. (A) Electromagnetic (B) Reciprocating (C) Centrifugal (D) Volute
Last Answer : (A) Electromagnetic
Description : The type of pump used for lifting large quantity of sewage is a __________ pump. (A) Gear (B) Centrifugal (C) Reciprocating (D) Plunger
Description : Priming of a centrifugal pump is done to (A) Increase the mass flow rate of fluid (B) Develop effective pressure rise by the pump (C) Avoid chances of separation inside the impeller (D) None of these
Last Answer : (C) Avoid chances of separation inside the impeller
Description : With increasing flow rate, the hydraulic efficiency of a centrifugal pump (A) Monotonically decreases (B) Decreases and then increases (C) Remains constant (D) Increases and then decreases
Last Answer : (A) Monotonically decreases
Description : Check valve provided in the discharge line of a centrifugal pump serves the purpose of controlling the (A) Back flow of fluid in the event of stoppage of pump (B) Discharge pressure (C) Flow of liquid during operation of the pump (D) All (A), (B) and (C)
Last Answer : (A) Back flow of fluid in the event of stoppage of pump
Description : Design of the casing of centrifugal pump should be such as to minimise the (A) Back flow through impeller (B) Loss of kinetic head (C) Loss of static head (D) None of these
Last Answer : (B) Loss of kinetic head
Description : In case of unsteady fluid flow, conditions & flow pattern change with the passage of time at a position in a flow situation. Which of the following is an example of unsteady flow? (A) ... level is maintained (D) Low velocity flow of a highly viscous liquid through a hydraulically smooth pipe
Last Answer : (B) Water flow in the suction and discharge pipe of a reciprocating pump
Description : A centrifugal pump is required to be primed before starting if it is located (A) At higher level than water level of reservoir (B) At lower level than water level of reservoir (C) Both (a) and (b) (D) Neither (a) nor (b)
Last Answer : (A) At higher level than water level of reservoir
Description : With a constant diameter impeller of a centrifugal pump (A) Its capacity varies directly as the square of speed (B) Head varies as the square of speed (C) Horsepower input varies as the square of speed (D) Head varies as the speed
Last Answer : (B) Head varies as the square of speed
Description : Which of the following options will facilitate the achievement of a very high head (say 30 metres) in case of a centrifugal pump? (A) Increasing the impeller speed and the volute area (B) Increasing the number of vanes ... or more impellers in series on a single shaft (D) Either of (A), (B) or (C)
Last Answer : (C) Mounting of two or more impellers in series on a single shaft
Description : Head developed by a centrifugal pump depends on its (A) Speed (B) Impeller diameter (C) Both (A) and (B) (D) Neither (A) nor (B)
Last Answer : C) Both (A) and (B)
Description : Which is the correct relationship for a centrifugal pump? (Where, D = Impeller diameter, inches H = Head developed, ft of liquid pumped N = Speed of pump, rpm) (A) D = 1840 H0.5 /N (B) D = 1840 N/H0.5 (C) H = 1840 D0.5 /N (D) D = 1840 H/N
Last Answer : (A) D = 1840 H0.5 /N
Description : The head developed by a centrifugal pump is largely determined by the (A) Power of the pump (B) Nature of the liquid being pumped (C) Angle of the vanes and the speed of the tip of the impeller (D) Vapour pressure of the liquid
Last Answer : (C) Angle of the vanes and the speed of the tip of the impeller
Description : Erosion and pits formation on the impeller of a centrifugal pump may be due to (A) Cavitation (B) Low speed of impeller (C) Its operation with delivery valve closed for considerable time after starting the pump (D) Off centering of pump with motor
Last Answer : (A) Cavitation
Description : The capacity of a centrifugal pump Can be increased by increasing the (A) Impeller diameter or speed (B) Number of pumps and joining them in series (C) Number of pumps and joining them in parallel (D) All (A), (B) and (C)
Description : The maximum depth from which a centrifugal pump can draw water is (A) Dependent on the speed of the pump (B) Dependent on the power of the pump (C) 34 feet (D) 150 feet
Last Answer : (C) 34 feet