Design optimization of the double glass problem; application and limitations of CFD

A simple teaching example of optimization in fluid mechanics is given, where use is made of Computational Fluid Dynamics (CFD). This was carried out on the basis of the assumption that students are trained at a basic level in CFD. In the future, automatic optimization procedures will become very important in design problems. However, it must be emphasized that optimization in fluid mechanics is mostly not trivial. With automatic optimization, the problem formulation must be kept within its applicability range. Moreover, with geometric parameter variation, the (automatic) grid generation and refinement must be appropriate to obtain accurate results. Furthermore, the accuracy of the applied models in the equations must be in general better than the gain in optimization function. In order to illustrate these issues to students, an exercise is compiled using the modeling of double glass windows. The analysis (student assignment) is performed with the aid of COMSOL 3.4 with MATLAB.