Caliper Rattle Noise Simulation based on Explicit Solver and BEM

Brake caliper rattle noise is difficult to simulate. Many CAE engineers have been introducing rattle vibration not noise.Previous rattle noise simulation presented relative displacement results calculated by normal mode analysis, or vibration dB level not noise dB level. However rattle noise is combination of continuous impact noise. Impact noise should consider reflection, diffraction and refraction caused by transient nonlinear contact and local vibration especially during very short contact event. To simulate the impact noise, vibration and acoustic characteristics should be analyzed based on simple structure because there are many mechanisms to explain the impact noise.In this paper, rattle noise is simulated by LS Dyna which has explicit solver and BEM solver. The correlation between the test and CAE was conducted with simple beam rattle, and caliper system level which is corresponding to car maker test specification. Finally caliper system level rattle noise simulation can be verified. Further study will be more complex MoC (Motor On Caliper) rattle noise. Also this rattle noise simulation technology based on explicit solver and BEM could be expanded to creep groan, grind noise and squeal simulation.