At which component in an air-cycle cooling system does air undergo a pressure and temperature drop?

In an air-cycle cooling system, the component where air undergoes a pressure and temperature drop is the expansion turbine.

As air passes through the expansion turbine, it expands and does work on the turbine blades, resulting in a drop in pressure and temperature. This process is critical for the cooling effect in the air-cycle system, as the decrease in temperature is what enables the system to provide conditioned air for the cabin.

The expansion turbine operates by allowing the high-pressure, high-temperature air to expand, which lowers its pressure and temperature significantly. This cool, low-pressure air can then be utilized to cool the cabin effectively.

Other components like the heat exchanger, compressor, and condenser serve different functions in the cycle. The compressor, for instance, increases the air pressure and temperature, while the heat exchanger facilitates heat transfer rather than causing drops in both variables. This understanding of the roles within the cooling system is crucial for effective operation and troubleshooting of cabin atmosphere control systems.