TRG-TRC003-EN 7
period one
Heat and Refrigeration
notes
In refrigeration, as in heating, emphasis is placed on the rate of heat transfer,
that is, the quantity of heat that flows from one substance to another within a
given period of time. This rate of heat flow is commonly expressed in terms of
Btu/hr—the quantity of heat, in Btus, that flows from one substance to another
over a period of 1 hour.
Similarly, in the SI metric system of units, the rate of heat flow is expressed in
terms of kilowatts (kW), which are equivalent to kJ/sec. Kilowatts describe the
quantity of heat, in kJ, that flows from one substance to another over a period
of 1 second.
5DWHRI+HDW)ORZ
Figure 12