Coupled Modal Analysis and Aerodynamics of Rotating Composite Beam

Area of Science:

• Mechanical Engineering
• Composite Materials Science
• Aerodynamics

Background:

• Composite beams are crucial in rotating machinery, but their dynamic behavior under rotation is complex.
• Understanding modal analysis and aerodynamic interactions is vital for designing efficient and stable rotating structures.

Purpose of the Study:

• To perform experimental and numerical modal analysis of a cantilever composite beam.
• To investigate Campbell diagrams, natural frequencies, and modal shapes under varying rotation speeds.
• To analyze aerodynamic forces (lift, drag, moment) and their impact on the beam's dynamic response.

Main Methods:

• Experimental modal analysis of composite beams.
• Numerical simulations including Campbell diagrams and modal shape analysis.
• Aerodynamic force assessment using computational fluid dynamics (CFD) or wind tunnel testing.

Main Results:

• Identified classical single-mode behavior and innovative linearly coupled modal analysis.
• Developed an analytical description for coupled mode shapes involving bending, longitudinal deformation, and twisting.
• Observed pronounced dynamic couplings at a 45° preset angle, with minimal coupling at 0° and 90°.
• Characterized lift, drag, and moment for a rectangular profile in uniform flow, detailing static and dynamic aerodynamic responses.

Conclusions:

• The study provides a comprehensive understanding of the modal characteristics and aerodynamic behavior of composite rotating beams.
• The introduction of analytical descriptions for coupled mode shapes represents a significant advancement in the field.
• Results offer valuable insights for the design and optimization of composite structures in rotating applications.