¶ Liquid evaporator
Liquid evaporator calculation window to be used when calculating an evaporator where the media into evaporator is 100% liquid AND subcooled. This means when the temperature written into ”subcooled liq. Temp” it is not referring to same as in normal evaporator window. Here it states the actual temperature of the liquid being pumped into the evaporator.
The basic steam cycle or ORC (Organic Rankine Cycle) are typical applications where the subcooled liquid is being preheated and evaporated at the higher pressure and the condensed at low pressure, (see Ex. 2). The pressure difference is used for driving a turbine or expander, usually connected a generator producing electricity.
First the temperature will increase until evaporating occurs and then after full evaporation there is the superheating.
If there is no sub cooling in the liquid, please use normal evaporator window.
Ex. 1: Normal evaporator
Subcooled liq. temp. = 43°C
This is the temperature out of the condenser (4) so after the pressure drop from expansion valve the actual inlet temperature (1) to evaporator is 5.07°C
Fig. 1: Normal evaporator example
Ex. 2: Liquid evaporator
Subcooled liq. temp. = 50°C
This is the temperature of the subcooled liquid going into evaporator (2) (also same as out of condenser, 1) meaning also the change of enthalpy from to increase the temperature (50 - 90°C) to evaporation (2 to 3) is also considered.
Fig. 2: Liquid evaporator example
Not all fluids and refrigerants are available since Grid fluids are required for these calculations but the ones most commonly used (ORC application, R245fa, R134a) are available in SSP.