On-line performance optimisation of aero engine control system. (Q1421449)

Usually a turbo-jet engine performance optimization is performed off-line and does not take into account engine to engine parameters variations and engine degradation. Here, an approach is proposed for on-line numerical minimization of the individual engine specific fuel consumption (SFC) at constant thrust. The main control factors are the fuel flow into the combustion chamber \(W_f\) and the output nozzle area \(A_n\). To find the current SFC minimum, the \(W_f\) versus \(A_n\) dependence is approximated by the formula \(W_f=a_0+a_1A_n+a_2A_n^2\) and the coefficients \(a_0, a_1, a_2\) are estimated by the recurrent least squares method using current measurements of engine parameters.