EQUALITY-BASED FORMULATION FOR NON-SMOOTH VIBRATING SYSTEMS

Add to your list(s) Download to your calendar using vCal

• Prof. Christopher Pierre, Stevens Institute of Technology
• Friday 24 May 2024, 14:00-15:00
• Department of Engineering - LT6.

If you have a question about this talk, please contact div-c.

A new approach is presented for the vibration of non-smooth structural systems with dry friction and unilateral contact. These nonlinearities are ubiquitous in engineering, and turbomachinery rotors are a prime example of industrial systems subject to a variety of intermittent contact and frictional occurrences. While non-smooth nonlinearities are commonly expressed as a complementarity system of equalities and inequalities, the key idea here is to formulate them as non-smooth equality-only conditions, which together with the equations of motion are then satisfied in a weak integral sense through a weighted residual formulation. The resulting algebraic nonlinear equations are solved numerically using an adapted trust region nonlinear solver and basic integral quadrature schemes. The approach is developed for one-dimensional friction, extended to two-dimensional friction and contact, and applied to the fir-tree blade attachment of a helicopter engine bladed disk. The method is shown to be compact, effective, and computationally efficient. Periodic solutions with intricate sticking, sliding and separation phases are found with a high degree of accuracy for large numbers of Fourier harmonics. Importantly, the equality-based formulation does not suffer from the typical limitations or hypotheses of existing frequency-time domain methods for non-smooth systems, such as regularization, penalization, or massless frictional interfaces.

This talk is part of the Engineering - Mechanics Colloquia Research Seminars series.

This talk is included in these lists:

• All Talks (aka the CURE list)
• Cambridge University Engineering Department Talks
• Cambridge talks
• Centre for Smart Infrastructure & Construction
• Civil Engineering Talks
• Computational Continuum Mechanics Group Seminars
• Department of Engineering - LT6
• Engineering - Dynamics and Vibration Tea Time Talks
• Engineering - Mechanics Colloquia Research Seminars
• Engineering - Mechanics and Materials Seminar Series
• Engineering - Mechanics, Materials and Design (Div C) - talks and events
• Featured lists
• Interested Talks
• Lennard-Jones Centre external
• School of Technology
• Trust & Technology Initiative - interesting events
• bld31

Note that ex-directory lists are not shown.