Process to Simulate Active Tuned Mass Dampers to Reduce Interior Noise during Cylinder De-Activation Events

During cylinder deactivation events, high amplitude torque pulsations are generated at the crankshaft of the engine over a wide frequency range creating a potential risk for noise, vibration and harshness (NVH) performance of the vehicle. As passive tuned mass dampers are effective only in a narrow frequency range, active tuned mass dampers (ATMD) have become a popular choice to mitigate the risk. Often, engineers rely on finite element (FE) models of vehicle structures to make design decisions during the early stages of vehicle development. However, there is limited literature on the simulation of ATMD using FE techniques. Consequently, several details related to the ATMD design are decided through physical testing at the latter stages of vehicle development which is not ideal. To address these issues, a novel methodology to simulate an ATMD during cylinder deactivation events using FE technique is presented here. In this study, an ATMD based on force feedback control method was simulated in a FE model of a large SUV with body-on-frame architecture. The proposed methodology demonstrated that ATMDs not only reduce tactile vibrations but can also considerably reduce structure borne interior noise. After multiple simulations using the proposed methodology, an optimal location and mass of ATMD which yielded the lowest interior noise levels was identified. Such a methodology can be applied on computationally large FE models during early stages of vehicle development thereby reducing physical testing.