Predicting Drum Brake Noise Using Finite Element Methods 2002-01-3139

A method for predicting the propensity of a drum brake system to produce noise is presented. The method utilizes finite element models of the individual components of the drum brake system, which have been assembled into the system model of the brake assembly. An important step in this process is the tuning of the dynamic characteristics of the FEA model to ensure validation with experimental tests. Friction is the key element, which defines the behavior of the drum brake system. The system FEA model is assembled by coupling the lining and drum at the contact interface to simulate the friction interaction. This process produces an asymmetric stiffness matrix. A complex eigenvalue analysis identifies the system dynamic characteristics such as the frequency and damping for each vibration mode. The damping values reveal which modes are unstable and therefore likely to produce noise. The models thus developed were used to conduct sensitivity studies on several designs parameters of the system to determine values, which would tend to minimize noise. This sensitivity study identifies trends, which are useful in guiding the product design process.