Faculty of Engineering Technology
Department Applied Mechanics & Data Analysis (MS3)
Master programme Mechanical Engineering
As part of his / her master assignment
Maris, M.W.G. (Maarten)
will hold a speech entitled:
Stress Constrained Structural Optimization of Roller Coaster Support Structures
The conducted research has focussed on the development of a structural optimization method to minimize the use of material for roller coaster support structures whilst not violating certain stress criteria. These structures typically consist of long and slender members, hence a Finite Element (FE) model with beam elements resembling a realistic track curvature has been computed for the application of the optimization method.
Support columns are located along the length of the track at an interval small enough, such that the FE model is significantly stiffer than required to meet the stress criteria. The mass and Young's Modulus of these support columns depend on design variables. The objective function is the sum of the mass of the support columns and the stress criteria are expressed in the constraint equations. With the objective, constraints and design variables, the nonlinear constrained optimization problem is formulated.
The problem is solved by applying a Sequential Quadratic Programming (SQP) algorithm. The objective and constraints are formulated in such a way that the gradients can be analytically determined, allowing for exact gradients and less computational effort than using the finite difference method. Most design variables of the obtained solution equal zero. The remaining columns in the model have an adjusted Young's Modulus, thus making the solution applicable to a real design would require to adjust the radii of remaining columns to acquire the desired stiffness.
|prof. dr. ing. B. Rosic
dr. ir. j.P. Schilder
dr. J. Hazrati Marangalou
ir. F. de Ruiter CEng