Component mode synthesis with subspace iterations for controlled accuracy of frequency and mode shape solutions

•An effective approach to improve component mode synthesis results to reach a controlled accuracy is given.•The error is assessed and can be reduced to the desired level using subspace iterations.•The Craig–Bampton component mode synthesis scheme is used to demonstrate the approach that, however, is general.•Example solutions are given to illustrate the applicability of the solution approach.

The objective in this paper is to present an approach to improve component mode synthesis solutions using subspace iterations to obtain frequency and mode shape predictions of controlled accuracy. In traditional component mode synthesis analyses, the calculated frequencies and mode shapes are approximations of the exact frequencies and mode shapes of the finite element model, the error is unknown, may be large, and is usually not assessed. In the approach given here, the error is assessed and can be reduced to the desired level. The Craig–Bampton component mode synthesis is used, but the solution approach is also directly applicable to any other component mode synthesis scheme. Some example solutions are given to illustrate the use and the effectiveness of the solution approach.