Aadhya Bhaskar
Independent Researcher
India
ABSTRACT
This study presents an in‐depth investigation of vibration characteristics in rotating machinery using experimental modal testing tools available prior to 2016. Emphasis is placed on conventional impact hammer excitation and roving accelerometer techniques coupled with early data-acquisition systems such as Brüel & Kjær PULSE and LMS Scadas. Modal parameters—natural frequencies, damping ratios, and mode shapes—were identified for a laboratory-scale rotor system. Statistical analysis of repeated measurements ensured result reliability. Finite-element simulations using ANSYS Mechanical APDL 15.0 validated experimental findings. Comparison between simulated and measured modal frequencies revealed less than 5 % deviation for primary modes. The research elucidates the strengths and limitations of pre-2016 modal testing tools in rotating machinery diagnostics and provides guidance for engineers employing legacy instrumentation.
KEYWORDS
modal testing, rotating machinery, vibration analysis, experimental modal analysis
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