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Cargo trucks are one of the most important and flexible ways of moving cargo within inlands. In some countries, such as Brazil, the economy relies on them to transport all kinds of products, from field and factory to consumer. In order to reduce freight prices, beside route optimization, truck manufactures started to focus on the aerodynamics development of those vehicles, in order to improve the efficiency, reducing fuel consumption and emissions. Although the truck aerodynamics development is important, most vehicles are not manufactured or don’t consider the truck trailer, which plays a key role in the full aerodynamics performance of the truck, once it might increase the front area and also change the overall aero performance.

Thanks to advances in Computational Fluid Dynamics - CFD codes, i.e. algorithms and turbulence models, complex CFD vehicles simulations are increasing not only in academia, but also in the industry itself. The aim of the simulations is to verify the aerodynamic behavior of a car at early stages of the project, when no prototype is available, and to reduce the total aerodynamic development time of a new vehicle. The turbulence model considered in the CFD simulation should be able to capture the main flow effects around the vehicle. Most importantly, the predicted total drag value of the vehicle has to be comparable to the values obtained in wind tunnel tests. The main focus of the presented work is a comparison of wind tunnel and CFD results of the same small production hatchback vehicle.

Within the advances in Computer Fluid Dynamics algorithms and High Performance Computing, large clusters become available at low costs allowing virtual simulations that were not possible some years ago at reasonable costs and time. This work uses intensively this condition and applies these advances on brake system optimization. The methodology developed in the present work verifies the best angular position for caliper inside the wheel to reduce the rotor temperature during braking process such as downhill procedure. Thus, this method is applied to a mini-VAN vehicle, where the best position is found, based on two design parameters: rotor temperature and convection heat transfer coefficient. This study shows that the most suitable position for initial selection is the first one.

The advances in High Performance Computing-HPC and CPU's sizes and processing power, combined with new computational codes, which are capable of coupling different types of simulation, are the main contributors for the increasing number of the Multiphysics simulations inside the industry. Multiphysics are defined as simulations involving multiple physical models or multiple simultaneous physical phenomena. Among some examples, spray modeling is of great interest in several branches of the industry and, with the development on algorithms and codes, simulations presented reliable results, compared to experiments. This work aims to contribute to both Multiphysics and spray modelling by reproducing a rainstorm condition, focused on a vehicular application. This work objective is evaluate the possibility and feasibility to reproduce virtually rain storm condition on a highway checking water intrusion at Air Intake System - AIS and compare with physical test.

The brake system is of vital importance when engineering a new vehicle due to its implication with both safety and overall performance. One of the main questions that arise when designing the brake system, not only in terms of performance but also in efficiency and fuel economy is how to make a better brake rotor. When designing the brake rotor, thinking about mass reduction and design optimization is a desire not only for high-performance motorsport, but for daily user applications. The impact on the vehicle performance would lead to improved fuel economy and braking safety. In this work, we propose to exploit some characteristics that can optimize the rotor design to achieve better performance, compared to a baseline design proposed. Some constructive characteristics are kept constant such as the rotor diameter and thickness. The use of computational fluid dynamics (CFD) simulations is considered in this study as a benchmark to future physical prototypes experiments.

Autonomous vehicles, which are defined as capable of sensing environment and navigating without any human input, are the top trend of the automobilist industry in terms of technology. The computers responsible for the control are able to set the vehicle to optimum operation point. With the advent of Computational Fluid Dynamics -CFD software, it is possible to study drag reduction proposals when the vehicles drive at the velocity, which contributes to increase fuel economy. In this context, based on a sedan virtual drag model, several simulations cases were developed considering different vehicle arrays and changing the distance between each one. The study aims to demonstrate, using virtual simulations, the potential drag coefficient reduction when vehicles are moving in a constant speed and which configuration leads to better performance increment. Taking the isolated vehicle as the baseline value, all the vehicles in the different arrays were analyzed.

A real-time monitoring method for brake temperature rise in long downhill varying velocity according to a pattern to evaluate the BET (Brake Equilibrium Temperature) is expensive in time and money. The solution proposed here take advantage of recent advances in CFD Codes and computational power that allowed big models being run on clusters of production level by the industries worldwide. This paper takes advantage of these advances and proposes a methodology for Brake cooling simulation at downhill following a previously downhill map of time x velocity x pedal pressure. The methodology proposed presented 95% correlation with physical test and now is possible, in virtual word, to evaluate the entire downhill procedure for a new vehicle design before any physical prototype is available.

Vehicle fuel filling may not occur the fastest way, mainly due to the filler neck geometry and low fuel flow from the pump. When the fuel tank in empty, the previous interferences are increased, once the inner pressure increases, complicating even more the fuel filling activity. Another problem that occurs due to poor filler neck design is fuel pump nozzle shut off, once the fuel flow can’t overcome the tank inner pressure causing fuel to return, turning off the pump or even leakage. The recent advances in CFD Codes and computational power allowed multiphase simulations to be performed in production level by the industries worldwide. This paper takes advantage of these advances and proposes a methodology for fuel filling simulation using multiphase CFD simulation in order to evaluate a filler neck design, by measuring the total filling time.

Moving ground simulation plays an important role on aerodynamic studies of road vehicles, in order to reproduce the real movement condition. Due to cost of implementing a moving ground, many wind tunnels employ static ground simulation with boundary layer control. The work here presented aims to study using Computational Fluid Dynamics - CFD simulations the effect of using moving ground simulations with rotating wheels against a baseline configuration using both static ground and wheels over a small pick-up truck. The study aims to determine the influence of using different flow velocities on the drag coefficient measured over this vehicle using both ground configuration. For the cases here presented we performed steady state Reynolds-Averaged Navier-Stokes - RANS numerical simulations, following similar setup as the industry best practices and using the same mesh.