Experimental study on the performance of an aircraft environmental control system

In this paper, the experimental study on the off-design performance and dynamic response of an aircraft environmental control system (ECS) was presented. A bootstrap air cycle refrigeration system with high-pressure water separation was employed in the ECS. Both the static test and the dynamic test were conducted on the ECS. The performance of the key components including precooler, recuperator, compressor, and turbine was investigated. The test results show the performance of the tested ECS can meet the requirements of design. However, some parameters including outlet pressure, turbine efficiency, and rotational speed might vary obviously when the operation conditions changed. The outlet humidity ratio and outlet temperature might also fluctuate largely during the start-up process. It is necessary to take into account the off-design performance and the transient performance in the design of ECS.