Ali, Muhammad Junaid  <br/><br/>
Optimal Expansion of Interface Dynamics for Substructure Coupling / 
Muhammad Junaid Ali 
 - 251p.  soft copy  30 
<br/><br/> This thesis introduces a novel methodology for optimal interface expansion in dynamic<br/>substructuring, focusing on inaccessible and continuous interfaces. Unlike traditional<br/>approaches relying on modal parameters from Frequency Response Functions (FRFs), it<br/>employs a direct frequency-based method targeting interface Degrees of Freedom (DoFs),<br/>bypassing errors linked to modal identification. The System Equivalent Model Mixing<br/>(SEMM) technique is utilized to expand dynamics at the interface by integrating numerical<br/>and experimental models into a mixed model. Coherence is employed as a robust<br/>correlation metric, evaluating both phase and magnitude of FRFs. This research addresses<br/>optimal sensor placement (OSP) for effective expansion, testing nineteen stochastic<br/>metaheuristics categorized into swarm intelligence, surrogate algorithms, and physicsinspired methods to alleviate computational challenges of exhaustive searches. The<br/>Mountain Gazelle Optimizer (MGO) algorithm proved highly efficient for larger systems,<br/>while exhaustive search was effective for smaller cases. Validation involved cantilevered<br/>beam models and experimental setups, demonstrating strong correlation at interface DoFs.<br/>MGO proved to be 49 times faster than exhaustive search in identifying optimal sensor<br/>locations. The proposed methodology showcases practical applicability in achieving<br/>accurate dynamic expansions. 
<br/><br/><label>Subjects--Topical Terms: </label><br/>MS Mechanical Engineering      
<br/><br/><label>Dewey Class. No.: </label>621