In the past few years, usage of Hybrid Electric Vehicles (HEVs) has significantly increased due to the boosting damage in the global environment. When introducing new technologies, the manufacturers are facing stringent customer expectations regarding sound and comfort quality, dynamics and driveability of the vehicle. Moreover, HEVs are well known as smooth and silent drives, but due to increase in complexity, additional vibro-acoustic effects may concern the design of vehicle behaviour. With the absence of an Internal Combustion Engine (ICE) masking properties, noise and vibration (N&V) effects, which are of low importance in conventional drivelines, may become serious issues in a HEV. To investigate these effects and to support finding solutions to mitigate them, the following paper introduces a multi physics simulation model, which incorporates the domain of Internal Combustion Engine thermodynamics, the mechanical driveline system, electric components, the vehicle and the control system. The paper presents a detailed analysis of the starting behaviour of a micro/mild hybrid vehicle with Crankshaft Starter Generator (CSG). However, during the starting phase, an ICE is cranked with the help of an electric machine causing a sudden impact, which is due to rapid moment from machine. This impact leads to torsional vibration due to compression reaction and pumping pressure in the cylinder, as known to be 'Torque Ripple'. This effect then further excites vehicle body vibration (e.g. at driver's seat), which can be assessed by calculating its Vibration Dose Value (VDV). A combination of the AVL's Simulation Tools (BOOST RT - Engine Thermodynamics, EXCITE - Transmission model, and CRUISE - Vehicle and Driver model) is used to create the complete model. The paper also outlines the modeling procedure for the above domains, covering their interaction, and finally highlighting how different N&V effects can be simulated and evaluated in a comprehensive way.
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