Question 1

The exit velocity in the nozzle increases as per______________  
A)stagnation point
B)continuity equation
C)prandtl number
D)newton's law

Accepted Answer

The exit velocity in the nozzle increases according to the continuity equation, which states that the mass flow rate must remain constant throughout the nozzle. As the cross-sectional area decreases, the velocity must increase to maintain the constant mass flow rate.

Question 2

Compressible flow is a flow that deals with
A)fluid temperature
B)fluid pressure
C)fluid density
D)fluid geometry

Accepted Answer

Compressible flow primarily deals with changes in fluid density, which occur significantly when the fluid velocity approaches or exceeds the speed of sound.

Question 3

The coefficient of kinetic friction is less than the coefficient of static friction.

Accepted Answer

The coefficient of kinetic friction is typically less than the coefficient of static friction because it's easier to keep an object moving once it has already started moving than it is to start moving an object from rest.

Question 4

A cubical block rests on an inclined plane of ? = 1/?3, determine the angle of inclination when the block just slides down the inclined plane?
A)40°
B)50°
C)30°
D)20°

Accepted Answer

The angle of inclination, θ, when the block just begins to slide down an inclined plane is determined by the coefficient of static friction, μ, using the formula tan(θ) = μ. Given μ = 1/√3, tan(θ) = 1/√3 implies θ = arctan(1/√3) = 30°.

Question 5

When a gas is pushed through a pipe, the gaseous molecules are______________by the pipe's walls
A)attracted
B)absorbed
C)deflected
D)dissipated

Accepted Answer

When a gas is pushed through a pipe, the gaseous molecules are deflected by the pipe's walls. This is because the molecules collide with the walls and change direction, rather than being absorbed, attracted in a specific manner, or dissipated by the walls.

Question 6

Gas flows through the nozzle from an area of______________pressure (called the chamber) to one of______________pressure
A)high, low
B)low, high
C)same, same
D)constant, infinite

Accepted Answer

Gas flows from an area of high pressure to an area of low pressure, which is a fundamental principle of fluid dynamics. This is why gas in a nozzle moves from the high-pressure chamber to a lower pressure area.

Question 7

On what basis are fire and water tube boilers are classified?
A)depending the combustion products formed
B)depending the state of fuel
C)depending on the steam formation rate
D)depending tubular heating surface

Accepted Answer

Fire and water tube boilers are classified based on the configuration of the tubular heating surface through which heat from the combustion process is transferred to the water to generate steam.

Question 8

Stirling boiler is an example of which type of boiler?
A)inclined tube boilers
B)mobile boiler
C)fire tube boiler
D)water tube boiler

Accepted Answer

Stirling boiler is an example of a water tube boiler, where the water is contained inside the tubes and the hot gases pass around them.

Question 9

Which of these is a stationary boiler?
A)locomotive boiler
B)marine boiler
C)mobile boiler
D)babcock-wilcox boiler

Accepted Answer

The Babcock-Wilcox boiler is a stationary boiler, typically used in power plants and industrial settings, unlike locomotive, marine, and mobile boilers which are designed for movement or transportation.

Question 10

Which of these is a mobile boiler?
A)lancashire boiler
B)stirling boiler
C)locomotive boiler
D)cochran boiler

Accepted Answer

Locomotive boilers are specifically designed for mobility and are used in locomotives, making them mobile boilers. They are compact and designed to be moved as part of a locomotive.

Question 11

Are boilers defined on the basis of heat source.

Accepted Answer

Boilers can be classified based on their heat source, such as gas, oil, electricity, or solid fuels.

Question 12

What is the steam pressure limit of natural circulation boilers?
A)650bar
B)180bar
C)400bar
D)550bar

Accepted Answer

Natural circulation boilers typically have a steam pressure limit of around 180bar. This is because the circulation of water within these boilers relies on the density difference between hot and cold water, and at higher pressures, this natural circulation might not be efficient or sufficient.

Question 13

Which of the given boilers operate above critical pressure?
A)natural circulation boilers
B)forced circulation boilers
C)once-through boilers
D)water tube boilers

Accepted Answer

Once-through boilers operate above critical pressure, where water is converted to steam in a single pass without recirculation.

Question 14

Which type of boilers are called drum-less boilers?
A)natural circulation boilers
B)fire tube boilers
C)positive forced circulation boiler
D)forced circulation boiler

Accepted Answer

Positive forced circulation boilers are called drum-less boilers because they do not have a steam drum.

Question 15

Chances of sediments depositing inside the water tubes in the shell is less due to?
A)low working pressure
B)natural circulation of water
C)partial circulation of water
D)high working pressure

Accepted Answer

The answer of Chances of sediments depositing inside the water...

Question 16

Out of the given option choose the advantage that supports fire tube boilers?
A)water circulation is cyclic
B)used as a mobile boiler
C)water circulation is limited inside boiler shell
D)bursting of flue tube does not cause any explosion

Accepted Answer

Fire tube boilers have limited water circulation inside the boiler shell, which makes them simpler and less expensive to operate and maintain compared to other types of boilers.

Question 17

Tubular air preheater of a boiler is also called as______________
A)recuperative air preheater
B)elliptical air preheater
C)ovoid air preheater
D)squarish air preheater

Accepted Answer

Tubular air preheaters, where heat from the flue gases is transferred to the air through tubes, are known as recuperative air preheaters. This term highlights their function of recuperating or recovering heat.

Question 18

What does regenerative air preheater consists of?
A)rotor
B)skewers
C)propeller
D)piston

Accepted Answer

Regenerative air preheaters consist of a rotor which is used to transfer heat from the flue gas to the air used in combustion processes in power plants and other large boiler applications. This enhances efficiency by preheating the air before it enters the combustion chamber.

Question 19

Which fuel is prepared by moulding finely ground coal under pressure?
A)coke
B)charcoal
C)briquette coal
D)lignite

Accepted Answer

Briquette coal is made by compressing finely ground coal into a solid mass, making it easier to handle and transport. This process involves moulding the coal under pressure.

Question 20

Which fuel has the lightest liquid petroleum fraction?
A)diesel
B)petrol
C)distillate
D)kerosene

Accepted Answer

Petrol, also known as gasoline, is made from the lightest fractions of oil during the refining process, making it lighter than diesel, kerosene, and distillates.

Quiz 15: Boiler Systems and Fluid Dynamics

The exit velocity in the nozzle increases as per______________

Compressible flow is a flow that deals with

The coefficient of kinetic friction is less than the coefficient of static friction.

A cubical block rests on an inclined plane of ? = 1/?3, determine the angle of inclination when the block just slides down the inclined plane?

When a gas is pushed through a pipe, the gaseous molecules are______________by the pipe's walls

Gas flows through the nozzle from an area ofpressure (called the chamber) to one ofpressure

On what basis are fire and water tube boilers are classified?

Stirling boiler is an example of which type of boiler?

Which of these is a stationary boiler?

Which of these is a mobile boiler?

Are boilers defined on the basis of heat source.

What is the steam pressure limit of natural circulation boilers?

Which of the given boilers operate above critical pressure?

Which type of boilers are called drum-less boilers?

Chances of sediments depositing inside the water tubes in the shell is less due to?

Out of the given option choose the advantage that supports fire tube boilers?

Tubular air preheater of a boiler is also called as______________

What does regenerative air preheater consists of?

Which fuel is prepared by moulding finely ground coal under pressure?

Which fuel has the lightest liquid petroleum fraction?