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The purpose of this study was to develop a body of a competition vehicle, the sports prototype category. This category has the aerodynamics as one of its main features, so much of their good performance depends on your body. The project proposal was generating an initial 3D CAD geometry, based on studies and existing vehicles. After analysis of the initial model, modifications were proposed in order to achieve better results for a competition vehicle. The simulation of the airflow over the 3D model of the body was performed in three steps: generation of geometry in SolidWorks CAD program, discretization of the model and the limited domain around it, using mesh generation program ICEM, and resolution of the flow in program of Computational Fluid Dynamics (CFD), ANSYS (FLUENT). The turbulence model used in this work has two equations, which models the turbulent kinetic energy k and dissipation ε.

This work presents the results of the study of the forces involved in the rubbing friction between the moving parts of the Otto cycle internal combustion engine. In order to study the friction force, a Honda GX 35 engine was modified and a load cell was attached to its chassis. The friction forces among the internal parts of the engine were transferred to the engine chassis, and, by means of a support, to the load cell. Those forces were measured in several situations of the engine, making possible to identify the amount of friction related to each component. The total measured friction power was equal to 112W, representing about 10% of the developed power of the engine. The results obtained by the tests showed the contribution of each individual part of the engine on the friction losses. By the results, it was possible to propose modifications to reduce the total internal friction of the engine, in order to increase its efficiency.

This paper presents a study developed in order to improve the aerodynamic performance of an automotive prototype by means of simulations carried out by a software that makes of the finite volume method. The prototype will be built at the Laboratory of Automotive Engineering of the Lutheran University of Brazil - ULBRA. Taking into account the original design of the automotive prototype, three virtual models were generated and analyzed. There were three steps to simulate the aerodynamic behavior on a 3D model: generation of the geometry with the employment of CAD software, generation of the mesh for the faces and volume that involve the car, using specific software, and solving the flow, with a CFD software. The results of the analysis allowed identifying the model with the lowest aerodynamic drag. That model had some modifications on its design, when compared to the original one, like wheels and their housings.

This paper presents a system developed for measurement of force, based on a load cell. The aim was to design a device capable of measuring the components of the force, drag and lift, which acted over automotive spoilers. In order to enable the system to measure the drag and the lift force, it was necessary to develop a system capable of measuring only the components of interest, uncoupling efforts, such as multiple solicitations and vibration. Measurements of force were carried out over an airfoil, employing the measuring system described in this paper. The results showed that the values of the forces that acted over the airfoil were in agreement to the expected. Airfoils are used mainly in automotive racing cars to increase adherence between the tires and ground. Car prepares have made use of theirs experience to determine the best type and angle of attack for the airfoils.

This work was made for drag force determination applied over the body of a super economic vehicle and respectively the drag coefficient, through a model in reduced scale, aerodynamic methods measurements in wind tunnel and CFD. For the research was built a model in vehicle scale of 1:6, where is analyzed in a wind tunnel with open section of 0.28 m2. The research were accomplished by drag force in a scale model where was determined through a data acquisition system that is made up: a flexible stem located at the centre of the model, tied to the same a string that made traction in the system through a rolling and a mass on the balance in the wind tunnel external part. The main results obtained in the accomplished work were the drag coefficient for a very low speed of 3.6 km/h so with that the determination drag coefficient can have an estimate drag force applied in the vehicle body that belongs to 3.56 N to a speed of 25 km/h.

The objective of this work is analyze the weight influence in super economic vehicle rolling resistance tyre for low velocity. One of the principal factors in fuel consume is the rolling resistance, once, in low velocity the aerodynamic drag is not very pronunciation. The rolling resistance analysis was made using a rolling belt instrumented with velocity between 1.5 km/h and 9 km/h) and weight between 0 (zero) and 300 N. The analysis results, permits an equation elaboration, relationship weight and velocity for one tyre rigidity.