It is less common and often more difficult to use CFD to analyze more complex parts of the airplane, such as high lift systems, engine compartments, auxiliary power units, or the behavior of the efflux from engine thrust reversers.

When dealing with thrust reversers, designers must know exactly where the exhaust plumes go, and they must know it early in the design cycle, because it affects such basic decisions as the placement of the engine on the wing. The enabling technology and research group at Boeing's commercial aircraft unit has developed a computer simulation that provides an early look at thrust reverser exhaust plumes.

The entire CFD analysis, from geometry definition to solution, can be completed in about three days. Tests that involve geometry changes, such as the repositioning of the cascades or the nacelle relative to the wing, or variation of the cascade angles, can be accomplished with minimal remeshing and analysis.

Wind tunnel testing and expense are reduced, but the key benefits are time and risk mitigation. Our process increases early confidence in the design and enables us to shorten the development cycle and deliver a quality product on schedule.