Abstract
Although brake squeal noise has been studied for many years, it is still challenging to remove or reduce squeal noise. Structural changes of brake system to reduce squeal noise are usually made through dynamometer testing in an iterative way based on engineering knowledge, past experience and etc. While these methods work well for simple problems, they are time consuming when there are squeal of multiple frequencies.
Complex eigenvalue analysis is a widely accepted tool for reducing brake squeal noise in the brake industry. Many papers proved that complex eigenvalue analysis is useful for reducing instabilities of brake system. This paper presents a new procedure for reducing instabilities. That is to separate contributing modes of the most contributing component using shape optimization. Desirable directions for separation of contributing modes are determined by modal participation factor to system (MPFS), modal participation factor to component (MPFC) and generalized coordinate (GC). Shape optimization is carried out using Altair Optistruct software to increase frequency difference between the contributing modes in the component level. The objective function of the optimization is mass minimization and design variables are defined in several domains of component. The frequency difference of contributing modes is set to constant value as constrain conditions.
The results show that this procedure can be successfully applied to complex eigenvalue analysis for reducing brake squeal noise and increase efficiency by eliminating the trial and error process.
KEYWORDS – Brake Squeal, Complex Eigenvalue Analysis, Frequency Separation, Shape Optimization, Modal Participation Factor, Generalized Coordinate