Design & Optimization of CV shaft system to address powertrain induced NVH issues

The automotive industry is a crucial sector that plays a significant role globally. Government policies have a profound impact on this automotive industry in defining the regulatory standards and emission controls. Such regulations incentivized automakers to invest in research and development complying those standards towards reduction of vehicle emission which intern result in higher torsional vibrations and excitations amplitudes. To address the rising NVH related concerns in driveline system. Drive shafts (CV shafts) is an important component in power-train system in vehicle. Drive shaft’s main purpose to transfer torque from engines to wheels at multiple speeds with different articulation angles. The roughness generated by the engine follows a transfer path from engine to transaxle and transaxle to half shafts in monocoque vehicles which generates discomfort to the drivers whenever the vehicle is driven. The roughness can also be addressed by proper design of driveshaft stiffness and tuning mass dampers. In this paper we focus on parametric changes on drive shaft torsional stiffness and tuned mass damper to address Engine roughness and driveline induced noise. Test measurement is done to measure baseline driveshaft bending frequency without dampers. AMESIM 1D simulation model is developed to reproduce Bending frequency and mode shapes. Optimization for the convergence on stiffness and damper frequency is done. With the new stiffness shaft and tuned damper vehicle has improved on the noise pattern, magnitude of oscillations and shift in natural frequency. Keywords: IC engine, NVH, CV shafts, Resonance.