Chapter 113

Question 0

The rate at which a system will remove heat from the refrigerated medium is defined as ______.

Answer 0

Capacity, or net refrigerating effect (both are acceptable)

Question 1

Heat, whose application causes a rise in temperature, is called ____ heat

Answer 1

Sensible

Question 2

One tonne of refrigeration is defined as:
A) 13958 kJ per day
B) 100 kJ per minute
C) 233 kJ per minute
D) 13958 J per hour
E) 335 J per second

Answer 2

C) 233 kJ per minute

Question 3

If chilled water at 2*C circulates through an evaporator and then is used in a cooling coil to cool an air duct, you would expect the evaporator temperature to be:
A) less than 2*C
B) at 2*C
C) slightly higher than 2*C
D) much higher than 2*C
E) unknown

Answer 3

A) less than 2*C

Question 4

The temperature at which a liquid refrigerant evaporates is dependant on the ________.

Answer 4

Pressure and temperature of the refrigerant in the evaporator.

Question 5

Latent heat may be defined further with respect to the states of the substance changing phase. Name the type of latent heat required to change ice from a solid state to a liquid state or from a liquid state to a solid state.

Answer 5

Fusion

Question 6

Explain how temperature at which a refrigerant boils in a refrigeration system is controlled.

Answer 6

Controlled by using an expansion valve at the inlet of the evaporator and a thermostat on the medium to be cooled. Based on the set point of the thermostat, the flow rate through the expansion valve is controlled.