RFRG 6036 - Refrigeration Theory (Chp 15) Flashcards
The net refrigerating effect of a refrigerant is the amount of heat:
A) Discharged by the condenser
B) Absorbed by the refrigerant in the condenser
C) Absorbed by the refrigerant in the evaporator
D) Discharged by the refrigerant in the evaporator
E) Absorbed by the evaporator
C) Absorbed by the refrigerant in the evaporator
NOTE: KEYWORD ‘‘EVAPORATOR’’
Heat, that causes a drop in temperature when removed, is called _____ heat:
A) Radiant B) Latent C) Convective D) Sensible E) Conductive
E) Conductive
How many kilowatt-hours will a 24 tonne refrigeration system use in 24 hours?
A) 13 958 B) 8 040 000 C) 232.8 D) 4732 E) 2233
E) 2233
The pressure ratio of the refrigeration system is calculated by dividing the:
A) Suction pressure by the discharge pressure
B) System volume by the cylinder volume
C) Absolute suction pressure by the absolute discharge pressure
D) Absolute condenser pressure by the absolute evaporator pressure
E) Discharge pressure by the suction pressure
E) Discharge pressure by the suction pressure
In the case of a simple ice box which of the following heat transfers is correct?
A) Air gives up sensible heat; ice gains latent heat
B) Air gives up latent heat; ice gains latent heat
C) Air gives up latent heat; ice does not gain any heat
D) Air gives up sensible heat; ice gains sensible heat
E) Air gives up sensible heat; ice does not gain any heat
A) Air gives up sensible heat; ice gains latent heat
In a compression refrigeration system, the evaporator:
A) Is in the cooled space B) Is where the refrigerant is condensed C) Increases the refrigerant pressure D) Is used to dry the refrigerant E) Is cooled by the air
A) Is in the cooled space
Capacity and performance calculations are performed by means of:
A) Psychometric charts B) Refrigerant tables C) Trigonometric tables D) Steam tables E) Actuarial tables
B) Refrigerant tables
Temperature control in a refrigeration system is accomplished by:
A) Regulating the pressure in the evaporator
B) Changing refrigerants
C) Increasing water flow to the condenser
D) Increasing refrigerant flow
E) Increasing compressor speed
A) Regulating the pressure in the evaporator
Refrigeration is possible because of a refrigerant’s capacity to transfer:
A) Electrical heat B) Mechanical heat C) Cold D) Latent heat E) Radiant heat
D) Latent heat
Note: refrigerant capacity to transfer
The rate at which a system will remove heat from the refrigerated medium is defined as:
A) Net refrigerating effect B) Differential efficiency C) Compression Ratio D) Coefficient of Performance E) Refrigeration capacity
E) Refrigeration capacity
