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The increasing market of the continuously changeable transmissions demands that its characteristics of performance fully are known and constantly developed. Of the some existing constructive types one initially opted to the modeling of the system of pulleys of changeable diameter and leather strap. Knowing, that the transmissions are part of the train of force of any vehicle, the model will go to include the characteristics of exit of the engine, torque and rotation and all the components of an automatic transmission that uses CVTs. The initial objective is to determine the geometry of functioning and the positioning of the leather strap in the CVT. Saber its behavior, if it is playing its role in the excellent way.

A Torque converter is a type of hydro-mechanical device, vastly utilized in the automatic transmission of vehicles and other machines. It is a critical component of the transmission system, having a direct impact on the fuel economy and vehicle´s performance. Computational Fluid Dynamics (CFD) has been employed by many authors and engineers to better understand the complex behavior of fluids inside of torque converters, in a way that it provides design improvements and increases model accuracy. This article presents a methodology that applies CFD as a tool in the design process of automobile torque converters. Therefore, this paper performs an extensive review of CFD associated with torque converters, and the principal concepts are stated and used to have a better understanding of the system’s dynamic behavior. Additionally, this article details some of the work done to develop an automotive torque converter model using the commercial software ANSYS CFX.

Hybrid Electric Vehicles (HEVs) currently represent an alternative to reducing fossil fuel consumption used by internal combustion engines. This paper analyses, in a platform of computational simulation and also in experimental condition, the vehicle fuel consumption, before and after hybridization. It checks the similarity of behaviors and/or the investigation of possible differences between the developed mathematical model and experiments performed. Computer simulations help, through mathematical models, a better understanding of physical phenomena related to engineering problems. A well elaborated computer model has a high fidelity degree with the real systems, becoming a powerful analysis tool. The experiments besides allowing a proof of results, they contribute to a refinement of the simulated models. The hybrid technology under study is characterized by the coupling of two electric motors directly to the rear vehicle wheels.

The design methodology have been proved its effectiveness concerned to new products development, and due to the systematic approach it allows great variety of solutions and concepts developed in the early concept design phase. This paper shows two efficient methods in concepts generation, they are: the brainstorm and the morphologic chart. Both were successfully used and the result was a new concept of wheelchair motorization which the electric motors are activated only when the force applied over the propulsion ring exceeds a preset value. This new concept was registered at INPI as an invention patent.

Epicyclic gear trains are important part of automotive transmissions. They are present in automatic transmissions and in differentials of most vehicles. The dynamic behavior of a single epicyclic gear is well known, and this study presents the results obtained based in a model of a complete transmission. Initially the Wilson gearbox is presented. The main principles of the model are described. Following, the results of a simulation using the model are shown. Finally, the influence of the inertias in the model are presented and it is done some discussion about it

Due to the current changes in the automotive industry several new technologies are being developed and the old ones analyzed. The epicyclic gear trains, or planetary gear trains, are important in the automatic transmissions. In this paper a model is presented to describe the behavior of the transmission during the process of gear change. For this the system chose must be fully described, that means the relation among the rotations of the components must established.

The development of hybrid vehicles has reached in recent years a high technical and commercial importance. In general, varied vehicular settings enable a motorization with several alternatives and conventional energies combined in order to increase the performance while reducing consumption and environmental impact. In the context of hybridization, particular attention has been given to vehicles that consider a secondary driving source of electric nature, mainly in countries where its cost is relatively low when compared with the cost of fossil fuels such as gasoline. This paper aims to achieve an economic and energy analysis of a hybridized vehicle. The last one has a conventional traction front-wheel driven by an internal combustion engine (ICE) and an electric traction rear-wheel propelled by electric motors (EMs) in-wheel.

This paper focus on the analysis of energy management for hybrid electric vehicles. The development of higher efficiency vehicles depends on the analysis of vehicle characteristics and driving conditions. Sizing the energy capacity of the storage system and defining the type of components, batteries or other kinds of electric components has a direct influence over the performance, consumption and autonomy of the vehicle. The forces involved in a vehicle movement such as aerodynamic drag, rolling resistance, grading resistance, are fully dependent on the conditions of the route; most situations should be represented on the driving pattern cycle, used for emissions and consumption tests, which will be presented and discussed. Modeling vehicle dynamic to analyze power and energy requirements of the vehicle during different test cycles provides an indication of the influence of hybrid technology in performance and fuel consumption.

The purpose of this paper is evaluating the amount of kinetic energy available to be regenerated by a hybrid electric vehicle (HEV) undergoing the Brazilian standardized driving cycle. Improvements on energy efficiency of the cars has become an urgent target of the Brazilian industry since Brazil launched a new automotive regulation imposing the reduction of 15.5% on the fuel consumption of the vehicles to be sold in this country in 2017 comparing to 2011. The HEVs are a possible solution for this situation. They are widely known by the high efficiency, mainly the ones capable to make the regenerative breaking, rescuing an already paid energy. Before the launch of HEVs in Brazil, the feasibility of these vehicles has to be accurately studied and one aspect to be evaluated is how much energy is possible to be rescued in the Brazilian standardized driving cycle.

Chassis dynamometers are important equipment to perform vehicular experiments in the automotive industry. Usually, these equipments are used according to standard procedures for emissions, fuel consumption, and performance analyses. In this paper, an alternative procedure was developed to experimentally determine the dynamometer inertia and losses related to bearings and transmission systems. Furthermore, a study on the tires rolling resistance, considering a double tire-roller contact, was carried out. The experiments were performed in a 4x2 chassis dynamometer with four rollers, equipped with an eddy current brake (coupled to a transmission reducer of 2.5 instrumented with a 3000 Nm torque flange) and with a 30 CV AC electric motor (coupled to a planetary transmission with reduction of 4.43 and instrumented with a 500 Nm torque flange). The dynamometer was also instrumented with an encoder system for speed measurement.

The gear shifting strategies strongly influence the vehicle fuel consumption because they change the powertrain inertia and the engine operation point. The literature normally presents gear shifting strategies based on the engine power and torque to improve the vehicle acceleration performance. Strategies based on fuel economy are difficult to determine due to a large number of factors that influence the engine behavior such as the available transmission ratios, required acceleration and vehicle speed. In this paper it was evaluated the influence of the addition of more gear ratios in the vehicle gearbox, which initially contains five available gear ratios. For each proposed gearbox configuration, the gear shifting strategy was optimized through an algorithm developed to improve the engine fuel consumption in the Brazilian standard urban driving cycle NBR6601.

The automotive industry's recent push towards developing electric and hybrid electric vehicles is a direct response to the growing global pressure due to environmental concerns and has resulted in a search for significantly cleaner and more efficient vehicles. Not only, in order to achieve its purpose, has this search highly depended on the development of advanced technologies. Among all systems and subsystem from a vehicle the powertrain system is going to be the focus of this work. The main goal of the present work is to get a complete mapping of all the functions, components and flows of information and energy, through the application of an existing methodology of analysis, known for “function structure technique”, on the described product. Therefore, this mapping will supply a better understanding of the product architecture. First of all, the composed system, for the hybrid vehicle powertrain, is divided hierarchically in subsystems according to the existing assemblies.

One traditional solution to start an internal combustion engine is the starter motor. Since its conception little was changed in its operational dynamics, even after passing by several design optimization processes. This fact elapses from the absence of application of an analysis tool capable to express the existing relations between its subgroups and the functions that these play. The main goal of the present work is to get a complete mapping of all the functions, components and flows of information and energy, through the application of an existing methodology of analysis, known for “function structure technique”, on the described product. Therefore, this mapping will supply a better understanding of the product architecture. First of all, the composed system for the starter motor is divided hierarchically in subsystems according to the existing assemblies. The operation chain is then separated through static and dynamic inspections during its use in the combustion engine.

Had to the development of new projects of vehicles more economic as for example, the hybrid vehicles, have become bigger investments in transmission systems mechanics more adjusted. Thus being the increasing market of the continuously changeable transmissions it demands that its characteristics of performance fully are known and constantly developed. Of the some existing constructive types one initially opted to the modeling of the system of pulleys of changeable diameter and leather strap. To leave of this modeling one became alterations of some components and verified the behavior of this CVT in a simulation of passage of a vehicle. This passage was drawn so that the vehicle more faced daily situations of a vehicle considered in a track accented, that requested of the transmission the reactions boundary lines that supplied to torque and power of enough engine, or, so that the vehicle executed the passage, a not to leave of the limitations of the system and the CVT.

Improvement of fuel economy is one of the most important development targets of modern passenger car engines. Modern solutions such as Direct Injection, Variable Valve Trains, or Cylinder Deactivation help to obtain this requirement. Each one of these techniques optimize the thermodynamic efficiency of the engine. However, the mechanical structure of combustion engines shows many areas of possible optimization regarding the mechanical efficiency. Engine friction affects the overall fuel consumption, mainly under low speed conditions combined with part load. Low speed/part load conditions are relevant for the real life fuel consumption of an engine, as well as friction improvements have significant effects on the fuel economy. The valve train drive produces the dominant friction portion under these conditions. Hence the friction optimization of this engine subsystem is one of the key issues regarding mechanical efficiency.

This study aims to evaluate the impact that changes in the parameters of the project to a continuously variable transmission has on its ability to transmit torque and power. A half-toroidal transmission is cinematically analyzed and key geometric parameters and their relationships are studied and characterized. A change in the parameters of the transmission geometry allows a verification of their influence on the entire system live-time for any type of cycle, as defined in the theory of life provided the causes of failure, fatigue and subsurface. Additionally is possible to evaluate the capability of transmitting torque through the theory of Elasto-Hydrodynamic (EHD) contact relationship and the range of possible transmission ratio to be achieved. In this paper, a geometric model of a traction based Half-toroidal CVT (see figure 1) were explored by adding new geometric parameters related to the system control mechanism (the roller tilting angle).

The search for better energy efficiency is leading the developments in automotive industry, looking for opportunities to reduce losses, optimizing the design and getting better efficiency of every component. This paper will present a non-linear dynamic study of interaction between commercial vehicle and the environment, considering all the influence of their dynamic characteristics in the fuel consumption. The first step is to analyze all variables that influence the dynamic behavior and then construct a mathematical model based on energy and based on forces (Newton). The interaction between the vehicle and its environment and the response of it will be considered as influent aspects and should be included into vehicle dynamic modeling.

The hybrid electric vehicle (HEVs) is an alternative to reduce the high dependence on petroleum products, because maintains the characteristics attributed to conventional vehicles such as performance, safety and trustworthiness and reduced the fuel consumption. Some modifications are necessary in the vehicle longitudinal dynamics equationing, to provide a specific power management control system, because of the electrical power source addition that complements the conventional engine and powertrain system. In this paper is used the HEV parallel configuration, where both drive systems are directly connected to the vehicle wheels, maintaining the engine/powertrain in the front wheels and electric motors directly coupled to the rear vehicle wheels.

The main objective of this work is the analysis of the reliability of mechanical components, as well as its application in failure tests commonly used in the practice, in this case, tests for obtaining and verification of the natural frequency associated to the first vibrational mode of turbocharger blades. Of the statistical theory applied to tests of components, it was made a rising of the types of used tests and its application with respect to the sampling of the population in study. Soon after, an analysis is proceeded on correlation and regression of the obtained data of the tests and of the adjustment of curves. Experimental tests were accomplished in the bank of tests of Schwitzer in two different models of turbocharger, and mensured the natural frequencies in a certain number of samples, all of them with the same number of blades..

One traditional solution to start an internal combustion engine is the starter motor. Little has been changed in its operational dynamics and conception, even after several design optimization processes. This fact stems from the absence of application of an analysis tool capable of showing the existing relations between its subgroups and the functions performed. But, once that these relations are explained and the basics functions are revealed, it is possible to generate a group of new technical solutions to perform the same functions. In order to achieve this goal, the present work applied a Morphological Analysis on the group of functions that is necessary and sufficient for a starter motor. The analysis of the Morphological Field revealed the nowadays trend of technical solutions and some solutions that hasn't been explored yet.