To understand the information required and provided by our simulator, it is necessary to comprehend the following concepts:
- Evaporation Temperature
It is the temperature at which the refrigerant changes from liquid to vapor in the evaporator, absorbing heat from the space or medium to be cooled. It is measured in °C or °F, and to achieve it, an appropriate pressure in the evaporator is required. In a pressure-enthalpy (P-h) diagram, it corresponds to the refrigerant temperature in the saturation zone during evaporation. - Superheat
It is the increase in temperature of the refrigerant in the vapor state above its evaporation temperature, after completing evaporation in the evaporator. It is measured in °C or °F and is calculated as the difference between the vapor temperature at the evaporator outlet and the saturation temperature at the evaporator pressure.
Example: If the evaporation temperature is 0°C and the vapor exits at 5°C, the superheat is 5°C. It is important to ensure there is no liquid in the compressor.
- Condensation Temperature
It is the temperature at which the refrigerant changes from vapor to liquid in the condenser, releasing heat to the external medium. It is measured in °C or °F and largely depends on the external environment and the efficiency of the condenser cooling. In the P-h diagram, it corresponds to the refrigerant temperature in the saturation zone during condensation. - Subcooling
It is the decrease in temperature of the refrigerant in the liquid state below its condensation temperature, after completing condensation in the condenser. It is measured in °C or °F and is calculated as the difference between the saturation temperature at the condenser pressure and the liquid temperature at the condenser outlet.
Example: If the condensation temperature is 40°C and the liquid exits at 35°C, the subcooling is 5°C. It improves cycle efficiency by increasing cooling capacity.
- COP (Coefficient of Performance)
The COP is the coefficient of performance, a measure of the efficiency of a refrigeration system. It is defined as the ratio between the heat absorbed in the evaporator (refrigeration effect) and the work consumed by the compressor to achieve said cooling.
It is dimensionless. A higher COP indicates greater efficiency. For example, a COP of 3 means that for every unit of energy consumed, the system transfers 3 units of heat.
- Discharge Temperature
It is the temperature of the refrigerant in the superheated vapor state at the compressor outlet, before entering the condenser. It is measured in °C or °F and is significantly higher than the condensation temperature due to compression. It depends on the discharge pressure, the type of refrigerant, and the cycle conditions (such as superheat). It is a key indicator for evaluating compressor performance and avoiding excessive overheating. - Enthalpy at Each Point in the Cycle
Enthalpy is a thermodynamic property that represents the total energy (internal energy plus the energy associated with pressure and volume) of the refrigerant at a specific point in the cycle, measured in kJ/kg. In a basic refrigeration cycle (compressor, condenser, expansion valve, evaporator), enthalpy is calculated at key points (numbered according to the typical P-h diagram) as h1, h2, h3, h4.
