Maae 2400 Exam

Front 1

Is a system in which no transfer of mass may cross the system boundary but energy transfer may occur

Back 1

Closed system (control mass)

Front 2

Is a system in which Mass may cross the boundary in addition to the energy mass is flowing across the boundary

Back 2

Open system (control volume)

Front 3

A transformation from one state to another which is defined by changes in properties

Back 3

A process

Front 4

Is a property that is dependent on the size of the system; examples include mass, volume, energy

Back 4

Extensive property

Front 5

Values that are independent of the size of the system, name examples (4)

Back 5

Intensive property

Density, specific volume, pressure, temperature

Front 6

is the transfer of energy from more energetic particles of a substance to adjacent particles that are less energetic due to interactions between particles, is stationary heat transfer between liquids, solids, and gases

Back 6

Conduction

Front 7

Is the energy transfer between a solid surface and an adjacent gas or liquid flowing across it

Back 7

Convection

Front 8

Is the energy transfer that requires no medium the energy, is transported by electromagnetic waves or photons

Back 8

Radiation

Front 9

a system that undergoes a cycle that delivers a network transfer of energy to its surroundings while communicating thermally with two bodies one hot and one cold

Back 9

Power cycle

Front 10

a system that undergoes a cycle that transfers energy by heat into the system from a cold body and discharges energy by heat transfer from the system to a hot body

Back 10

Refrigeration cycle

Front 11

A system that undergoes a cycle that transfers energy by heat into a system from a cold body and discharges energy by heat from the system to a hot body

Back 11

Heat pump cycle

Front 12

Label 1 to 5

Back 12

Front 13

When can a gas be treated as ideal?

Back 13

Using the compressibility chart as Z approaches one the gas can be treated as an ideal gas

Front 14

a device in which work is done on a gas flowing through the device in order to change the state of the gas, typically to increase the pressure

Back 14

Compressor

Front 15

A flow passage of varying cross-sectional area in which the velocity of a gas or liquid increases in the direction of flow

Back 15

Nozzle

Front 16

a device and which Powers developed as a result of a gas or liquid passing through a set of blades attached to a shaft free to rotate

Back 16

Turbine

Front 17

A device in which work is done on a liquid flowing through the device in order to change the state of the liquid, typically to increase the pressure and/or elevation

Back 17

Pump

Front 18

a device that achieves a significant reduction in pressure by introducing a restriction into the line through which a gas or liquid flows

Back 18

Throttling device

Front 19

What is the advantage of a superheated Rankine cycle?

Back 19

They have a higher average temperature so the thermal efficiency is higher, it increases steam quality at turbine exit and turbines don't like liquids so that's good

Front 20

What are some pros and cons of the Brayton cycle with reheat?

Back 20

-they have a greater net work, temperature at the turbine exit is higher so potential for regeneration is better, decreases bwr

-bad because it decreases thermal efficiency

Front 21

Is a macroscopic characteristic that is numerical and independent of the system's history

Back 21

Property

Front 22

Is work a property?

Back 22

No

Front 23

What is internal energy and how is it expressed?

Back 23

The energy from the breakage of chemical bonds, expressed as ∆U

Front 24

Specifies the number of independent properties

Back 24

State principle

Front 25

Name some irreversibilities in a system

Back 25

- heat transfer through a finite temperature difference

- expansion of a gas or liquid to a lower pressure

- spontaneous chemical reaction

- friction

- current flow through our resistance

- magnetization or polarization

Front 26

What is the reason for using the approximated reversible processes?

Back 26

Determine the best performance, implement factors to account for inefficiencies after

Front 27

What are the Carnot corollaries?

Back 27

- all reversible power cycles between two thermal reservoirs have the same efficiency

- efficiency of a irreversible power cycle is less than the reversible power cycle

Front 28

A process in which heat isn't transferred between the system and the surroundings, there's no change in entropy

Back 28

Adiabatic

Front 29

Heat transfer goes from the hotter to colder and less work is done

Back 29

The Clausius statement

Front 30

In thermodynamics cycles not all of the heat transfer from a thermal reservoir will be converted to work

Back 30

Kelvin-Planck statement

Front 31

What makes for a thermal reservoir?

Back 31

Absorbs or supplies finite amounts of heat without changing temperature

Front 32

What is an isentropic cycle?

Back 32

Both adiabatic and reversible

Front 33

What will fix the state?

Back 33

Knowing two independent properties

- P and T inside the vapor dome = NO

- quality and P or T outside the vapor dome = NO

Front 34

Can a reversible power cycle achieve a cycle efficiency of 100%?

Back 34

No

Front 35

Why is it good to decrease mass flow?

Back 35

Smaller pump, small heat exchanges equal cost efficient

Front 36

Which cycle is represented?

Back 36

Carnot Cycle

Front 37

Which cycle is represented?

Back 37

Ideal Rankine cycle