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This paper presents a standardization model for the analysis of rolling bearings in transmission systems. A procedure was applied to assist gearbox prototype development. A solid methodology with robust software, based on international standards, allowed the development engineers to shorten simulation time. In this case, the calculations were performed taking into account system elasticity, which resulted in an exact calculation of the internal load distribution in the bearing, including contact pressure, tilted position and with rolling element profile, considering effects of lubrication conditions and contamination. The program also evaluates the resulting forces of gears, displacement, shaft deflection, contact pressure, stresses, torsion and inclination of the shafts. All the information processed aims at providing safe design, optimal solution and cost impact.

Clutch systems applications require that their components resist to high dynamics and static efforts that should be considered in the development process. These requirements are determined taking account the vehicle application, such as loadcases, materials, life time and environment conditions. In the case of CRB components generally the design is based on contact angular ball bearing. Normally static analysis are performed, computing stresses and displacements, however in this specification the results are checked using static and fatigue safety factors according to the strength assessment evaluation, Germany standard: FKM (Richtlinie - Rechnerischer Festigkeitsnachweis für Maschinenbauteile). Actually more powerful computers have reduced gradativally the cost for industries and with the constant improvements of FE programs, it is possible to simulate the complete assembly using contact interactions to get closer to the reality.

Dual Clutch Transmissions have conquered an important fraction of the market, mainly in Europe, as a result of their improvements concerning efficiency. Once the power flow from engine to the transmission is not interrupted, fuel efficiency increases radically. Furthermore, extreme fast and soft shifts provide the most dynamic and smooth acceleration of any vehicle on the market, being particularly suitable on high performance vehicles. The drivers have also experienced singular comfort, since they can choose whether to control the shifting or let the computer do it automatically. Nevertheless, to overcome the elevated requirements imposed to the system components, in special the release bearings, the industry has dispended considerable efforts on the development of new processes and design methodologies.

The challenge to find optimal solutions regarding energy efficiency in vehicle systems such as transmissions, engine and chassis involves the understanding of friction torque, friction losses and loading conditions interactions. Design variables such as internal dimensions, component profile and roughness will lead to a final component from which needs input energy to start and maintain movement. Even a component without load requires a minimal amount of energy and assembled in a vehicle will contribute to fuel consumption and emissions. The same component over loading conditions will turn these values higher due to the energy balance. Using engineering modeling techniques, the loading conditions, such as radial forces and rotation speed were implemented by parametric analysis and a dynamic model was built to obtain the variable contribution in energy-based design.

Hydrodynamic bearings are widely used in rotating machines, being the element responsible for the interaction between the rotor and the supporting structure. Therefore, in order to describe the dynamic behavior of the rotating shafts, it is necessary to know the journal bearings dynamic characteristics. For this reason, this work aims to analyze the influence of three different geometries of journal bearings when operating in a small turbocharger for vehicular application, which implies in high rotation speed and load capacity. In this paper the analysis will be done through the frequency response of the proposed system and the equivalent damping and stiffness coefficients coming from the oil film present in the bearings. These dynamic coefficients are obtained with a spring-damper approach, in order to represent the inherent flexibility and damping of the oil film.

One of the engineering challenges is to design the optimal bearing arrangement that will meet a balance of cost and project requirements. In order to increase performance, durability and efficiency the use of advanced virtual simulation can match these commitments in a fast and safe way. In a design approach it must be considered that the best rolling bearing will fail in the best application, when both systems are not adapted to each other. The key for getting this is to understanding the complete system by virtual simulation and not only to specify a rolling bearing. Based on the system understanding, boundary conditions can be better defined all relevant influences are considered and design variations can be fast made to perform the system. Using sophisticated CAE - tools this paper will present how systems, drive trains and rolling bearings can be investigated by virtual simulation in a different abstraction levels.

This paper presents a software developed to apply the Hertz contact formulation to bearings with rolling elements, estimating the occurrence of surface fatigue failure in this kind of parts. Considering the wide range of designs in the automotive industry using this kind of bearings, a dedicated software, using a simple language, becomes a useful tool to reduce the design time, predicting in a satisfactory manner the failure of the bearing. The software developed shows a high level of accuracy, when compared to data provided by rolling bearing manufacturers.