Book Description
In 1979 the Propulsion and Energetics Panel of AGARD established a Working Group named WG 14 whose terms of reference were to study the averaging techniques used for non-uniform internal flows. This problem is relevant to gas turbine systems, in which the actual flows are usually heterogeneous and three-dimensional. Nevertheless, the test analysis and performance prediction methods are presently based upon simple one-dimensional models. Members of WG 14 first reviewed current practices as employed by research and development teams in various research establishments and industry. The Group also undertook a theoretical analysis of the relations which may be correctly applied to steady flows. Consequently it was possible to discuss and classify known averaging methods. The theoretical study concludes by proposing refinements to known methods and a new approach to averaging for use with engine components and propulsion system analysis. A large variety of possible averaging techniques were identified. Some were based on theoretical considerations, others were without justification except in their simplicity or common usage. All the averaging procedures were tested and compared by preparing a number of sample calculations in ducted flows, turbojet components and a complete propulsion system.
