How do refrigeration systems primarily control the internal temperature of the cargo?

Refrigeration systems primarily control the internal temperature of the cargo by adjusting the refrigerant flow. The refrigerant is a fluid with thermodynamic properties that allows it to absorb heat from the cargo space as it circulates through the system. When the temperature inside the cargo area rises above the desired set point, the system responds by allowing more refrigerant to flow through the evaporator coil. This increased flow helps to absorb additional heat, thereby lowering the internal temperature.

Effective temperature control is essential in refrigeration systems, as maintaining the proper environment is crucial for preserving the quality of perishable goods during transport. The modulation of refrigerant flow allows for precise temperature management, accommodating fluctuations in both external conditions and the heat released by the cargo itself.

While fans play a role in distributing cooled air, they do not directly control temperature. Insulation is important for preventing heat transfer but does not actively manage the internal temperature. Additionally, manipulating pressure levels in the system is part of maintaining the overall refrigeration cycle but is not the primary method used for temperature control within the cargo area.