Modeling and design optimization of an industrial vibrating dryer through Finite Element analysis

This thesis investigates the structural dynamics of an industrial vibrating dryer used for the processing of organic natural acid crystals, in which fatigue cracks developed after 150 operating hours. Experimental investigations revealed the occurrence of resonance phenomena. Despite the implementation of an initial structural modification, the dynamic problem was not completely resolved, motivating a deeper investigation of the machine's behavior. This work addresses this problem by developing Finite Element models and validates them against experimental evidence. The modeling strategy combines engineering-based simplifications with experimental evidence to reproduce the dynamic response while maintaining computational efficiency. The models schematize parts excluded from the geometric domain through physically motivated equivalent formulations that preserve the essential dynamic characteristics of the system. The validated numerical models provide information that experimental testing alone could not supply by identifying the deformation patterns associated with the measured natural frequencies. Building upon these results, this work employs the validated computational model as a predictive design tool to evaluate alternative structural solutions. It compares retrofit interventions and a complete re-design of the supporting structure in terms of dynamic performance, structural efficiency, additional mass, manufacturability, and practical feasibility. The proposed solutions significantly increase the separation between the operating excitation frequency and the structural natural frequencies, thereby mitigating the resonance risk. This work demonstrates that physically consistent engineering assumptions and experimental validation enable Finite Element models to reproduce the dynamic behavior of complex machinery. The numerical framework provides a predictive tool for future structural modifications while reducing development time and material consumption.