Optimisation by Evolutionary Algorithms of Free-Layer Damping Treatments on Plates

The problem of controlling or reducing vibration levels is very common in many different applications. From costly aeroplane fuselages to cheap domestic appliances the prob- lem can be tackled with the appropriate use of free layer damping treatments (FLDT).1 This technique, based on the distribution of layers of visoelastic material on the vibrating parts, is frequently adopted since it is cheap, efficient and easily applicable either at the design stage or in situ as a cor- rective measure. Due to these advantages and few limitations, not much care is taken to optimise the material distribution. Conversely, the necessity to produce lighter and quieter products will force the designer to optimise these treatments too. Under these circumstances, the most appropriate optimi- sation objectives seem to be the maximisation of the achiev- able damping levels and the minimisation of the amount of added material. In this work the potential of the genetic algorithm for the determination of th