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Jaguar Land Rover (JLR) has designed and developed a new inline 4 cylinder engine family, branded Ingenium. In addition to delivering improved emissions and fuel economy over the outgoing engine, another key aim from the outset of the program was to reduce the combustion noise. This paper details the NVH development of the lead engine in this family, a 2.0 liter common rail turbo diesel. The task from the outset of this new program was to reduce the mass of the engine by 21.5 kg, whilst also improving the structural attenuation of the engine by 5 dB in comparison to the outgoing engine. Improving the structural attenuation by 5 dB was not only a key enabler in reducing combustion noise, but also helped to achieve a certified CO2 performance of 99 g/km in the all-new Jaguar XE model, by allowing more scope for increasing cylinder pressure forcing without compromising NVH.

Control of powertrain radiated noise and of excitations induced by the Powertrain through the mounts are key aspects towards designing the Powertrain induced NVH performance of a vehicle. During the concept, as well as later stages of Powertrain development, use of simulation tools for MBD, FEA and Vibro-Acoustics can help to evaluate and lead the Powertrain design decisions. In the present work, the flexible MBD software packages, AVL-Excite and MSC-NASTRAN, have been used to predict upstream mount vibrations and surface vibrations of the Powertrain structure. The radiated sound pressure was predicted using LMS Virtual Lab software. In MBD simulation of the Powertrain, the linear elastic Powertrain components (Crankcase, Cranktrain, Drivetrain, etc.) were FE modeled and condensed using MSC-NASTRAN; condensed linear elastic Powertrain components were then connected by means of non-linear joints at the bearing locations.