Flexible Aluminum lubes and a Least Square Multi-objective Non-linear Optimization Scheme.

摘要

The automotive industry currently uses rubber hoses as the media carrier between e.g.the radiator and the engine,and the basic idea is to replace the rubber hoses with flexible aluminum tubes.A good quality is defined through several quality measurements,i.e.in the current case the key objective is to produce a flexible convolution through optimization of the tool geometry,but the process should also be stable,and the process stability is evaluated through Forming Limit Diagrams.Typically the defined objectives are conflicting,i.e.the optimized configuration represents therefore a trade-off between the individual objectives,in this case flexibility versus process stability.The optimization problem is solved through iteratively minimizing the object function.A second-order least square scheme is used for the approximation of the quadratic model,and the change in the design parameters is evaluated through the trust region scheme and box constraints are introduced within the trust region framework.Furthermore,the object function is minimized by applying the non-monotone scheme,and the trust region subproblem is solved by applying the Cholesky factorization scheme.An optimal bell shaped geometry is identified and the design is verified experimentally.