Basit ve karmaşık yapılar için aktif titreşim kontrolü ve aktif yapısal akustik kontrol

In this thesis, a novel methodology is developed for active vibration control and structural acoustic control of simple and complex structures. In the first section, optimal positioning of collocated sensor/actuator pairs for vibration control of plate-like structures are investigated and performance of an active vibration controller is studied numerically and experimentally. In the second part of the thesis, a new design methodology for local and global vibration control system is developed for a 3D shell structure with complex geometry and complex boundary conditions. The objective of the local vibration control is to reduce vibration energy at the sensor location whereas the objective of the global vibration control is to reduce vibration over the entire structure. In order to achieve, effective vibration suppression of the structure, local and global performance indices are defined and used for the optimization of sensor/actuator pair position as well as the controller parameters. The methodology is applied to suppress vibrations on the front panel of a vehicle as a case study. A finite element model of the vehicle is built and used for the frequency response analysis in the presence of engine disturbances. Then, local and global optimization studies are carried out for positioning the sensor/actuator pair and parameter tuning of the controller. By comparing controller active and inactive cases, the vibration suppression performance of the controller is demonstrated locally and globally.In the final part of the thesis, a novel methodology is presented for design of an active structural acoustic control (ASAC) system on a complex 3D shell structure with complex geometry and complex boundary conditions. The actuator/sensor position and control parameters are optimized based on acoustic performance indices. As a case study, a vibro-acoustic model of a vehicle is used to present the developed methodology. It is shown that on a complex 3D surface, a well-positioned collocated sensor and actuator pair with optimized design parameters can suppress the vibration spatially on a complex shaped panel and therefore it can reduce the sound pressure level inside the passenger cabin. It is shown that the proposed methodology can be successfully applied for the structures that have complex shape and boundary conditions for noise suppression