ChE 123: Production of Power from Heat (1)

Question 1

this cycle consists of two isothermal and two adiabatic steps

Answer 1

carnot cycle

Question 2

if work is produced in a turbine, what will happen to pressure and temp.?

Answer 2

pressure and temperature drops

Question 3

Large scale heat-engine in which the working fluid (water) is in steady-state flow successively through a pump, boiler, turbine, and condenser in a?

Answer 3

cyclic process

Question 4

these steps are considered as the “work conversion steps”

Answer 4

adiabatic steps

Question 5

in carnot cycle, isothermal steps, this is absorbed by the working fluid for the phase change to liquid

Answer 5

temperature of the cold reservoir/heat leaving the condenser

Question 6

it is used to transfer heat from a burning fuel to the cycle and the condenser transfer heat from the cycle to the surroundings

Answer 6

boiler

Question 7

in carnot cycle, isothermal steps, this is absorbed by the working fluid for the phase change to vapor

Answer 7

temperature from the hot reservoir/heat entering the boiler

Question 8

how many steps does carnot cycle consist of?

Answer 8

1. two isothermal steps
2. two adiabatic steps

Question 9

in isentropic compression, what will happen to pressure and temp.?

Answer 9

pressure and temperature increases

Question 10

this cycle operates reversibly

Answer 10

carnot cycle

Question 11

two temperature reservoirs in carnot cycle

Answer 11

1. boiler temperature
2. condenser temperature

Question 12

Provides the maximum possible efficiency for a plant working between two temperature reservoirs

Answer 12

carnot cycle

Question 13

increasing pressure would increase?

Answer 13

saturation temperature

Question 14

Large scale heat-engine in which the working fluid (water) is in steady-
state flow successively through a?

Answer 14

1. pump
2. boiler
3. turbine
4. condenser

Question 15

a step where a high-pressure steam from the boiler expands in the turbine (pressure and temperature drop as work is extracted)

Answer 15

adiabatic expansion (turbine work production)

Question 16

problem with carnot cycle lead to the use of another cycle called?

Answer 16

rankine cycle

Question 17

main purpose of cyclic process is to produce useful _________________ from heat

Answer 17

power (electricity)

Question 18

a step where sat’d liquid from the condenser is pumped back to the boiler (increase pressure).

Answer 18

adiabatic compression (pump work input)

Question 19

its main purpose is to produce useful power (electricity) from heat

Answer 19

steam power plant

Question 20

it is a large scale heat-engine in which the working fluid (water) is in steady-state flow successively through a pump, boiler, turbine, and condenser in a cyclic process

Answer 20

steam power plant

Question 21

this step is necessary to restore the fluid to a high-pressure state, making it ready for the next heat absorption and expansion phase

Answer 21

compression

Question 22

it is the most efficient possible cycle operating between low and high temperatures

Answer 22

carnot cycle

Question 24

it doesn’t depend on the working substance — it could be steam, air, or any fluid — and it’s an ideal benchmark for real engines

Answer 24

carnot cycle

Question 25

it is a problem in carnot cycle in which saturated steam that enters turbines produces an exhaust with high-liquid content, that causes?

Answer 25

erosion

Question 26

two problems in carnot cycle

Answer 26

1. produces an exhaust with high-liquid content that causes erosion 2. difficult to design a pump that takes in wet steam and pumps out saturated liquid

Question 27

what steps in a carnot cycle that has problems?

Answer 27

step 2-3: adiabatic expansion step 4-1: adiabatic compression

Question 28

it is used to transfer heat from a burning fuel to the cycle and the condenser transfer heat from the cycle to the surroundings.

Answer 28

boiler

Question 29

this is widely used in real-world power plants

Answer 29

rankine cycle

Question 30

The diagram of the practical power cycle illustrates the ___________________ on step 2-3 and step 4-1.

Answer 30

irreversibilities

Question 31

These steps are no longer isentropic and tend to lean towards greater entropy.

Answer 31

step 2-3 and step 4-1