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The ability to perform dynamic simulations of the motion of an engine on its mounting system during large amplitude deflections can provide important benefits in vehicle development. This information can aid in the packaging of components in the engine box area, it can provide insight into ways to improve the durability of the engine mounts, and it can provide insights into how large amplitude motions of the engine may be affecting vehicle noise, vibration, and harshness (NVH). One problem in simulating the motion of the engine for large amplitude deflections of its mounts is accounting for the hysteretic damping effects observed in elastomeric engine mounts. This paper discusses a simple three element model for an elastomeric isolator that can represent this hysteresis effect. The model is used to predict behavior of an elastomeric isolator, and test results verifying the predicted behavior are presented.

Accurate powerplant inertia information is important for noise, vibration, and harshness (NVH) simulation and analysis of vehicle dynamics, both for engine mount systems in isolation and as part of vehicle system models. Because of the amount of effort involved in experimentally testing for the inertia properties of an automotive powerplant, typical practice is to test a single build variation of that powerplant. This inertia property information is then used to approximate the powerplant inertia properties of the other build conditions. This paper evaluates the effect of powerplant build options on powerplant inertia properties. An analytical approach is used, where powerplants are assembled analytically from a database of component inertia information, and the powerplant inertia properties determined. Powerplant inertia property results for a set of four cylinder, in-line powerplants, with different build options, are presented.

Serpentine belt system has been widely used during past years to drive automotive accessories like power steering, alternator, and A/C compressor from a crankshaft pulley. Instead of using multiple belt drives, the serpentine belt system uses a multi-rib flat belt, which wraps around several idlers and accessory pulleys. This design requires the use of a tensioning device to maintain adequate belt tension for preventing slip. Crankshaft torsional vibrations can lead to excessive rotational vibrations in poorly designed accessory systems. This can lead to undesirable noise and excessive slip, which can hamper the belt and bearing life. The value of these rotational frequencies and system response is of utmost interest to the accessory drive designer. While it is not practical to shift these rotational frequencies out of the operating range of an engine, a belt layout with these frequencies at non-dwell engine speed is highly desirable.

For the 2003 model year DaimlerChrysler Corporation will launch a totally new 5.7L V-8 engine for applications of the Dodge Ram pick-up truck. The new engine was created largely within a digital environment using the latest computer aided design (CAD) and computer aided engineering (CAE) techniques and tools. Utilizing a co-located team of design engineers, designers, and CAE engineers enabled the simulations to impact the design from program inception to the assembly line, saving program time and investment. This paper describes the successful merging of design and advanced analysis techniques by highlighting examples throughout the new HEMI® program. Case studies include issues in the areas of structural optimization, engine loading, lubrication circuit, cooling circuit, and manufacturing.