Use of genetic algorithms for the design of rotors

The problem of finding an optimum shape for rotating discs is a classical one and has received considerable attention; in the present paper an attempt to use genetic algorithms is described. The problem of finding the constant stress profile by using genetic algorithms is tackled, firstly using the well known results of conventional methods. The problem of optimizing the shape of pierced discs is then attempted with results which are affected by strong stress concentrations, owing to simplifying assumptions in the stress analysis implicit in the so-called disc theory. This drawback is exactly the same which limits the usefulness of conventional solutions. In order to overcome this problem, particular formulations of the fitness function aimed to discourage shapes leading to strong stress concentrations are introduced, showing that profiles which lead to very favourable stress patterns when analysed using tridimensional methods can be obtained even with an optimization procedure essentially based on the disc theory. A profile of a disc flywheel with the rim and hub obtained using the genetic approach shows the results which can be obtained using this optimization technique.