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Effects of roller diameter and number on the contact pressures, subsurface stresses and the fatigue lives of cam roller follower bearings are investigated in this paper. Finite element analyses under plane strain conditions were conducted to identify the effects of the diameter and number of the rolling elements and the thickness of the outer ring. The fatigue life of the inner pin generally increases as the roller diameter increases. But, reducing the number of rollers to accommodate larger rollers does not necessarily increase the fatigue life. The inevitable decrease of the thickness of the outer ring due to the increase of the roller diameter results in the increase of compliance for the outer ring. This increase of compliance leads to excessive deformation of the outer ring and consequently more load must be carried by fewer number of rolling elements.

Computer applications have been widely used to assist product design. The successes and sophistication of computer aided engineering (CAE) techniques are respectfully recognized in this field. CAE applications in the manufacturing area however are still developing, although the manufacturing community is increasingly starting to pay attentions to computer simulations in its daily workings. This paper will briefly introduce some of these applications and promote awareness of computer simulations in manufacturing area. It contains four main sections: finite element analysis (FEA) in machining fixture design, FEA applications in component assembly, machining process simulations and machining vibrations in the milling operation. Each section comes with a practical case study, potential benefits are identified and conclusions are presented by using an integrated design and analysis approach.

The cambore distortion is one of major concerns of an engine performance. A good design does not ensure a quality product. To meet product performance requirements, engineering community turns efforts to both design and manufacturing at an early stage of product development. This paper will discuss this process by providing an example of design and manufacturing of an overhead cambore. In this study a methodology to evaluate bore distortions is introduced. FEA cambore distortion analysis will use it to provide necessary data so that the product team can make a sound decision.

A predictive knock model that utilizes a phenomenological modeling approach has been developed for predicting the onset of knock in gas engines. Several physical models have been developed and incorporated into WAVE, a comprehensive engine simulation code, including 1) a spatially resolved end gas thermodynamics model; 2) a model for calculating the chemical reaction rates of the reactants in the unburned zone; and 3) a model for approximating the heat transfer between the two-zone combustion model and end gas reaction model. The established predictive knock model has been demonstrated and validated against experimental data. A WAVE simulation model of the Caterpillar G3508 engine was created and used to predict engine knock over a range of fuels, spark timing and compression ratios. The computational results are compared to test data which were obtained from G3508 detonation timing test.