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The theory related to the thermal comfort of a human being is described in this article. It is not technically and economically feasible to provide optimal thermal comfort to a human being. The air temperature inside the vehicles is inhomogeneous mainly due to the ventilation system and to solar heat flux. The thermal stratification of air that results in difference of heat flux at the human body may cause thermal discomfort. In this case, it is important to quantify the degree of discomfort, which can be represented by the Predicted Mean Vote and Predicted Percentage Dissatisfied indices. This study intends to determine the thermal comfort for a human being inside vehicular cabins considering just the ventilation system with the same ambient temperature. A cabin of a vehicle is virtually reproduced in FLUENT® and the methodology of thermal comfort, based on previous works from the literature, is developed in Matlab 2010a and applied in this simulation.

Nowadays, one of the most important roles in vehicle development is the aerodynamic, which aims efficiency on fuel consumption and leads to a green technology. Several initiatives around the world are regulating emissions and efficiency of vehicles such as EURO for European Marketing and the INOVAR Project to be implemented in Brazil on 2017. Thus, this study intend to perform an optimization to minimize the drag force of a hatchback vehicle. The main goal of this work is demonstrate the potential of optimization techniques to provide an aerodynamic shape improvement for the driver side outside rear view mirror of a hatchback vehicle. The optimization solver used in this work is the Adjoint Solver, which makes shape sensitivity analysis and mesh/volume morphing. The study was conducted using CFD simulations to reduce the drag force of current production hatchback vehicle previously validated and correlated in wind tunnel test.

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.

Aerodynamics plays a key role in nowadays vehicle development, aiming efficiency on fuel consumption, which leads to a green technology. Several initiatives around the world are regulating emissions and efficiency of vehicles such as EURO for European Marketing and the INOVAR Auto Project to be implemented in Brazil on 2017. In order to meet requirements in terms of performance, especially on aerodynamics, automakers are focusing on aero-efficient exterior designs and also adding deflectors, covers, active spoilers and several other features to meet the drag coefficient. Usually, the aerodynamics properties of a vehicle are measured in both CFD simulations and wind tunnels, which provide controlled conditions for the test that could be easily reproduced. During the real operations conditions, external factors can affect the flow over the vehicle such as cross wind in open highways.

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.

The automakers pursue for fuel economy is increasing year after year, both by the demands of society and by political pressures, leading companies to develop new solutions and technologies in order to increase the energy efficiency of vehicles. With the advent of CFD software, it is possible to study drag reduction proposals, which contributes to increase fuel economy. In this context, based on a small sedan vehicle virtual drag model, correlated with the wind tunnel test, a conceptual wheel was assembled proposing 3 blade angles in order to verify the influence on the drag coefficient. Considering the drag contribution of wheel in total vehicle drag is around 25%, this work aims to show the sensitivity in the drag coefficient by changing the wheel rim of a small sedan vehicle.