In order to solve the difficulty to directly obtain all characteristic parameters of the components in the whole turbofan engine

it was determined ultimately that the number of corrected parameters by using the condition number of the correlations between parameters

on the basis of sensitivity calculation of the characteristic parameters of engine components to engine performance. Thus

the identification problem could be solved in engineering by the least square method. The simulation results show the efficiency of high compressor was 0.982 consistent with initial value of 0.98

indicating that the method is theoretically feasible. From the identification results of concrete example

the efficiency value of components were in accord with the actual results with the compressor temperature test; in contrast

the efficiency value compared with the design state was higher than 12.7%

which did not match the actual engine operating conditions. Clearly

the identification problem was ill-posed

so parameters can be amend should not exceed 6.