Interview Questions.

Question 1. How Cavitation Can Be Eliminated In A Pump?

Answer :

Increase the Pump size to One or Two Inch,
Increase the strain of the Suction Head,
Decrease the Pump Speed.
Question 2. Which Pump Is More Efficient Centrifugal Pump Or Reciprocating Pump?

Answer :

Centrifugal pump. Because float fee is better compared to reciprocating pump. Flow is smooth and it calls for much less space to put in. Lower preliminary price and lower maintenance price.

Aeronautical and Aerospace Interview Questions
Question 3. What Is Cavitation?

Answer :

Cavitation is the formation of vapor cavities (Air bubbles) in a liquid.

Question four. What Is Positive Displacement Pump?

Answer :

Positive displacement pumps are those that function with the aid of forcing a fixed quantity of fluid from the inlet pressure section of the pump into the release zone of the pump.

Question 5. What Is Kinematic Viscosity?

Answer :

The kinematic viscosity is the ratio of absolute viscosity to the density of the liquid.

Thermodynamics Interview Questions
Question 6. Differentiate Between The Uniform Flow And Non-uniform Flow?

Answer :

Uniform Flow: The waft is described as uniform float while in the go with the flow discipline the speed and other hydrodynamic parameters do not change from point to factor at any instant of time.

Non-Uniform Flow: When the rate and different hydrodynamic parameters adjustments from one point to any other the flow is described as non-uniform glide.

Question 7. What Is The Difference Between The Unsteady Uniform Flow And Steady Uniform Flow?

Answer :

Unsteady uniform go with the flow - changes with time.

Steady uniform go with the flow - does no longer alternate with time.

Fluid mechanics Interview Questions
Question eight. Why Centrifugal Pump Is Not Called As A Positive Displacement Type Of Pump?

Answer :

The centrifugal has various go with the flow relying on pressure or head, whereas the Positive Displacement pump has more or less regular drift no matter pressure.

Likewise viscosity is consistent for wonderful displacement pump wherein centrifugal pump have up and down value due to the fact the better viscosity beverages fill the clearances of the pump inflicting a better volumetric performance. When there's a viscosity alternate in supply there may be also greater loss within the machine. This method change in pump waft affected by the pressure alternate.

One greater instance is, nice displacement pump has more or much less constant efficiency, wherein centrifugal pump has various performance fee. SO Centrifugal Pump is not known as as a Positive Displacement Type of Pump.

Question nine. What Is Coefficient Of Contraction?

Answer :

Coefficient of contraction is the ratio of region of jet at vena contracta to the area of orifice.

The traditional cost may be taken as zero.64 for a sharp orifice (concentric with the go with the flow channel). The smaller the value, the extra effect the vena contracta has.

Question 10. Why The Centrifugal Pump Is Called High Discharge Pump?

Answer :

Centrifugal pump is a kinetic device. The centrifugal pump makes use of the centrifugal force to push out the fluid. So the liquid entering the pump gets kinetic strength from the rotating impeller. The centrifugal action of the impeller quickens the liquid to a high speed, transferring mechanical (rotational) power to the liquid. So it discharges the liquid in high charge.

It is given inside the following formulae:

Centrifugal force F= (M*V2)/R.
Where,
M-Mass
V-Velocity
R-Radius

Question eleven. How Cavitation Can Be Eliminated By Pump?

Answer :

Cavitation approach bubbles are forming in the liquid.

To keep away from Cavitation, we should boom the Pump size to One or Two Inch.
To increase the stress of the Suction Head, or Decrease the Pump Speed.
Question 12. Why Cavitation Will Occur In Centrifugal Pump And Not In Displacement Pump?

Answer :

The formation of cavities (or bubbles) is prompted by using go with the flow separation, or non-uniform float velocities, inner a pump casing. In centrifugal pumps the eye of the pump impeller is smaller than the go with the flow region of pipe. This lower in go with the flow place of pump effects in growth in waft fee.

So stress drop passed off among pump suction and the vanes of the impeller. Here air bubbles or cavities are shaped due to liquid vapour because of increase in temperature in impeller. This air bubbles are transmitted to pump which bureaucracy cavitation.

Aeronautical and Aerospace Interview Questions
Question 13. What Is A Radial-drift Turbine?

Answer :

In a radial-glide turbine, steam flows outward from the shaft to the casing. The unit is often a response unit, having both constant and shifting blades.

Question 14. What Are Four Types Of Turbine Seals?

Answer :

Carbon earrings geared up in segments around the shaft and held collectively through garter or retainer springs.
Labyrinth mated with shaft serration’s or shaft seal strips.
Water seals in which a shaft runner acts as a pump to create a hoop of water around the shaft. Use best treated water to keep away from shaft pitting.
Stuffing box the use of woven or tender packing rings which might be compressed with a gland to prevent leakage along the shaft.
Question 15. What Are Two Types Of Clearance In A Turbine?

Answer :

Radial – clearance at the pointers of the rotor and casing.

Axial – the fore-and-aft clearance, at the perimeters of the rotor and the casing.

Question sixteen. What Is The Function Of A Thrust Bearing?

Answer :

Thrust bearings maintain the rotor in its accurate axial position.

Question 17. What Is A Stage In A Steam Turbine?

Answer :

In an impulse turbine, the level is a fixed of shifting blades behind the nozzle. In a response turbine, every row of blades is called a "stage." A unmarried Curtis level can also consist of two or extra rows of shifting blades.

Question 18. What Is A Diaphragm?

Answer :

Partitions among strain stages in a turbine’s casing are referred to as diaphragms. They keep the vane-shaped nozzles and seals among the levels. Usually labyrinth-kind seals are used. One-half of the diaphragm is outfitted into the top of the casing, the opposite half of into the lowest.

Thermodynamics Interview Questions
Question 19. What Are The Two Basic Types Of Steam Turbines?

Answer :

Impulse type.
Reaction kind.
Question 20. What Are Topping And Superposed Turbines?

Answer :

Topping and superposed generators arc excessive-pressure, non-condensing gadgets that may be brought to an older, moderate-strain plant. Topping turbines obtain high-stress steam from new excessive-pressure boilers. The exhaust steam of the brand new turbine has the same strain because the old boilers and is used to supply the old mills.

Question 21. What Is A Combination Thrust And Radial Bearing?

Answer :

This unit has the ends of the Babbitt bearing prolonged considerably over the quit of the shell. Collars at the rotor face these thrust pads, and the magazine is supported inside the bearing between the thrust collars.