Two spool air cycle machine having concentric shafts

摘要

A two-spool air cycle machine includes a high pressure cooling turbine section; a low pressure cooling turbine section; and first and second shafts that are concentrically arranged and that are independently rotatable with respect to one another. A turbine wheel of the high pressure turbine section is secured to the first shaft, and a turbine wheel of the second turbine section is secured to the second shaft. Such an air cycle machine may be used a variety of different aircraft environmental control systems.