PIPE Elements 7

The ________ is the most fundamental principle in nature
a. conservation of atomic theory
b. conservation of mass
c. conspiracy theory
d. none of these

Formulates E =mc²
a. Einstein
b. Newton
c. Euclid
d. none of these

The conservation of mass equation is often referred to as the continuity equation in
a. thermodynamics
b. fluid mechanics
c. fluid dynamics
d. none of these

The amount of mass flowing through a cross section per unit time is called
a. volume flow rate
b. mass-volume flow rate
c. mass flow rate
d. none of these

In most practical applications

As a result

The velocity of fluid is zero at the wall and maximum at the center because of the
a. velocity effect
b. viscous effect
c. temperature effect
d. none of these

When the mass of control volume

When some mass ceases the control volume

If the boundary of control volume is stationary

The energy required to push fluid into or out of a control volume is called the
a. boundary work
b. non-flow work
c. flow work
d. none of these

Turbines

Is a process during which a fluid flows through a control volume steadily
a. variable flow process
b. steady flow process
c. non-steady flow devices
d. none of these

The heat and work interactions between a steady flow system and its surroundings
a. change with time
b. change with power
c. do not change with time
d. none of these

The power delivered by a system and the rate of heat transfer to or from a system_________during a steady-flow process.
a. remains constant
b. increase
c. decrease
d. none of these

During steady flow process

For steady flow devices

When a fluid stream enters and leaves as steady flow device at about the same velocity

Are commonly utilized in jet engines

A ________ is a device that increases the velocity of a fluid at the expense of pressure
a. nozzle
b. diffuser
c. venturi meter
d. none of thess

A ________ is a device that increases the pressure of a flyid by slowing it down.
a. nozzle
b. diffuser
c. pitot tube
d. none of these

The cross-sectional area of nozzle decreases in the flow direction of subsonic flows and increases for
a. hypersonic flow
b. steady flow
c. supersonic flow
d. none of these

The work termed for nozzles and diffusers is
a. zero
b. one
c. infinity
d. none of these

In steam

The work done in a turbine is ________since it is done by the fluid.
a. positive
b. negative
c. zero
d. none of these

Compressors

The work termed for compressors is negative since work is
a. done by the fluid
b. done on the fluid
c. rejection of fluid
d. none of these

A ________ increases the pressure of a gas slightly and this is mainly used to move a gas around
a. compressor
b. fan
c. pump
d. none of these

A___________is capable of compressing the gas to very high pressures
a. fan
b. compressor
c. turbine
d. none of these

________ are any kind of flow-restricting devices that causes a significant pressure drop in the fluid
a. condenser
b. compressor
c. throttling valve
d. none of these

The magnitude of the temperature drop during a throttling process is governed by a property called
a. Newton coefficient
b. Joule-Thomson coefficient
c. Joule coefficient
d. none of these

The work done in throttling valve is
a. zero
b. one
c. infinity
d. none of these

Throttling valves are called
a. isentropic device
b. isenthalpic device
c. chronic device
d. none of these

If the product P-v decreases

In throttling process

In the case of ideal gas

The section where the mixing process takes place is commonly referred to as a
a. mixing chamber
b. combustion chamber
c. air mixing
d. none of these

Are devices where two moving fluid streams exchange heat without mixing
a. adiabatic
b. recuperator
c. heat exchangers
d. none of these

Heat exchangers are widely used in
a. power plant
b. various industries
c. turbine
d. none of these

The simplest form of heat exchanger is a
a. tube heat exchanger
b. shell heat exchanger
c. shell and tube heat exchanger
d. none of these

For high speed flows

For fluid flow

kinetic energy is not neglected in calculations of _________.
a. high speed flow
b. low speed flow
c. steady flow
d. equilibrium flow

The combination if enthalpy and kinetic energy of fluid is termed as
a. combustion enthalpy
bn autoignition enthalpy
c. steady enthalpy
d. stagnation enthalpy

In the absence of any heat and work interactions and any changes in potential energy

Flows through thw nozzles and diffusers with increasing flyid velocity will create an equivalent ___________.
a. decrease inthebstatic enthalpy of fluid
b. increase in the static enthalpy of fluud
c. decrease in the internal energy of fluid
d. decrease in the dynamic enthalpy of fluid

Stagnation enthalpy represents the enthalpy of a fluid when it is brought to rest__________.
a. diabatically
b. adiabatically
c. isothermally
d. isobarically

During stagnation process

The properties of fluid at the stagnation in state are called:
a. stagnation
b. stagnation phase
c. stagnation state
d. stagnation vapor

Stagnation state and stagnation properties are indicated by the subscript
a. 0
b. 1
c. 2
d. 3

The stagnation state is called the isentropic stagnation state when the stagnation process is:
a. reversible as well dynamic
b. isotropic
c. adiabatic
d. reversible as well as adiabatic

The entropy of a fluid remains constant during
a. polytropic stagnation process
b. unsteady stagnation process
c. combustion process
d. isentropic stagnation process

Represents the temperature an ideal gas will attain when it is brought to rest adiabatically.
a. absolute zero temperature
b. stagnation temperature
c. boiling temperature
d. critical temperature

The term V²/2Cp responds to the temperature rise during such a process and is called the:
a. kinetic temperature
b. high temperature
c. dynamic temperature
d. elevation temperature

An important parameter in the study of compressible flow is the
a. speed of fluid
b. speed of sound
c. speed of light
d. speed of fluid flow

Is the velocity at which an infinitesimal small pressure wave travels through a medium.
a. subsonic velocity
b. hypersonic velocity
c. sonic velocity
d. monatomic velocity

Velocity of sound is

Is the ratio of the actual velocity of the fluid to the velocity of sound
a. Mach number
b. Froude Number
c. sonic number
d. control number

The flow is called sonic when Mach number is
a. equal to 1
b. less than 1
c. more than 1
d. none of these

The flow is sub-sonic when M is
a. greater than 1
b. less than 1
c. more than 1
d. none of these

The flow is supersonic when M is
a. greater than zero
b. less than 1
c. greater than 1
d. none of these

The flow is hypersonic when
a. M>1
b. M>>1
c. M=1
d. M=0

The flow is transonic when
a. M=0
b. M<1
c. M>1
d. M≡1

The pressure decreases as the temperature and velocity increases while the fluid velocity and Mach number
a. increases
b. decreases
c. remains constant
d. none of these

The density of fluid decreases as the fluid velocity
a. increases
b. decreases
c. remains constant
d. none of these

The flow area decreases with decreasing pressure up to a critical pressure value where the Mach number is
a. zero
b. unity
c. less than 1
d. greater than 1

The Mach number is unity or one at the location of smallest flow area

The velocity of fluid is keep on increasing after passing the throat although the flow area
a. increases rapidly
b. decreases rapidly
c. remains constant rapidly
d. none of these

The increase in velocity past the throat is due to the rapid decrease in the
a. fluid density
b. fluid specific
c. fluid temperature
d. fluid pressure

If the area of the duct first decreases and then increases then this is known as
a. converging nozzles
b. diverging nozzles
c. converging-diverging nozzles
d. none of these

The volume flow passes through a venturi meter is
a. increases
b. decreases
c. constant
d. varying

For a subsonic flow

For subsonic flow

Pitot tube is use to measure the
a. velocity of mass
b. velocity of pipe
c. flow
d. velocity of flow

For supersonic flow

For supersonic flow

The property of fluid at location where the Mach Number is unity( at the throat) are called
a. critical properties
b. sonic properties
c. dynamic properties
d. stagnation properties

The flow through the nozzle is
a. isentropic
b. polytropic
c. isobaric
d. isovolumic

If the reservoir is sufficiently large

The______is the pressure applied at the nozzle discharge section.
a. stagnant pressure
b. critical pressure
c. back pressure
d. atmospheric pressure

When the back pressure is reduced to lowest exit pressure

The mass flow rate through the nozzle is _____when M=1 or at the throat.
a. maximum
b. minimum
c. zero
d. none of these

An increase in stagnation pressure will increase the mass flux through
a. diverging nozzle
b. converging nozzle
c. converging-diverging nozzle
d. none of these

An decrease in stagnation pressure will increase the mass flux through
a. diverging nozzle
b. converging nozzle
c. converging-diverging nozzle
d. none of these

A converging-diverging nozzle is the standard equipment in
a. subsonic aircraft
b. supersonic aircraft
c. hypersonic aircraft
d. trisonic aircraft

For back pressure values

The flow process through shock wave is highly irreversible and cannot be approximated as being
a. polytropic
b. isometric
c. hyperbolic
d. isentropic

Is the locus of states which have the same value of stagnation enthalpy and mass flux are called
a. Fanno Line
b. Straight Line
c. Willan's Line
d. Criss Cut Line

Combination of mass and momentum equations into a single equations and plotted in h-s plane yield a curve called
a. Fair Line
b. Freh Line
c. Cutting Line
d. Rayleigh Line

Is the ratio of
Actual kinetic energy at nozzle exit
----------------------------------------
Kinetic energy at nozzle exit for isentropic flow
a. Turbo efficiency
b. effectivenesss
c. ratio
d. nozzle efficiency

Nozzle efficiencies range from
a. 78 to 89%
b. 80 to 90%
c. 90 to 99%
d. 93 to 98%

Is the ratio of
Actual velocity at nozzle exit
-------------------------------------
Velocity at nozzle exit for isentropuc flow
a. velocity coefficient
b. velocity ratio
c. peripheral velocity
d. speed ratio

Is the ratio of
Actual Mass flow rate through nozzle
------------------------------------
Mass flow rate through isentropic nozzle
a. flow ratio
b. flow factor
c. discharge factor
d. discharge coefficient

_______= Δh
------
V₁²/2

where:
Δh = kinetic energy which can be converted to pressure rise if the fluid is discharged at the actual exit stagnation pressure.
V₁²/2 = is the maximum kinetic energy available for converting pressure rise
a. enthalpy efficiency
b. kinetic efficiency
c. diffuser efficiency
d. convergence efficiency

Measure the diffuser's ability to increase the pressure of the fluid is
a. speed recovery factor
b. pressure recovery factor
c. volume recovery factor
d. diffuser recovery factor

Is the ratio of actual stagnation pressure at diffuser exit and the isentropic stagnation pressure.
a. pressure recovery factor
b. critical flow pressure
c. saturated stagnation pressure
d. none of these

Pressure rise coefficient is the ratio of actual pressure rise and the
a. pressure ratio
b. potential pressure
c. isentropic ratio
d. isentropic pressure rise

As the steam expands in the nozzle

The locus of points where condensation takes place regardless of the initial temperature and pressure at the nozzle entrance is called
a. Wilson's line
b. Willan's line
c. Transient Line
d. Control Line

law of thermodynamics that involves temperature in equilibrium is
a. First law
b. Second law
c. Third law
d. Zeroth Law