Parameter selection for aeroengine transient state gas path analysis

Compared with steady state data, engine transient state data cover a wider working scope of components, more complex operating conditions, and therefore can provide more abundant information regarding engine health status. To make the fullest use of engine transient data, this paper presents the methods on how to choose the proper measurements and health parameters when constructing an aeroengine gas path analysis system. The measurement selection based on sensitivity analysis is conducted, compared to which an effortless measurement selection method termed Minimum Identifiability Loss (MIL) is proposed. Aiming to reduce the estimation uncertainty, the analysis of maximal linearly independent group is presented to select optimal health parameters under the condition of limited measurements. Finally, the component health status identifiability analysis base on transient data also gives a good explanation to gas path analysis “smearing effect”.