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The limits of tailpipe CO2 emissions are getting lower worldwide and the automobile manufacturers are looking for both on-cycle and off-cycle technologies to reduce these emissions. Some new innovative technologies are being studied to help reduce emissions. The use of the so called eco-innovations such as a battery charging solar roof to claim off-cycle credits of CO2, is already regulated in Europe by the document “Technical Guidelines for the preparation of applications for the approval of innovative technologies pursuant to Regulation (EC) No 443/2009 of the European Parliament and of the Council”. According to this document, the average solar radiation in Europe is 120W/m2. In Brazil, in which the latitudes are lower than in Europe, the weighted average solar radiation, according to the licensing trend has not been calculated yet.

Plastic components of a vehicle are strongly affected by external environmental conditions. High temperatures can damage the components, influencing the behavior of other parts of the vehicle. In this work, the influence of temperature and weather conditions of the plastic components is evaluated. Results of tests of thermal fatigue carried out in laboratory are correlated with thermal solicitations obtained under several critical environmental conditions. Weather maps from several regions of Brazil were evaluated in order to identify critical conditions, and a vehicle was submitted to these critical ambient conditions. Ambient temperature, solar radiation and temperature of the plastic components were measured and compared with solicitations currently reproduced in laboratory. The maximum temperature values achieved by the components were determined, allowing the critical evaluation of the materials used in the car.

The main objective of this work is to study the influence of temperature and weather conditions on the thermal behavior of the plastic components of a vehicle considering several environmental conditions. It is intended to correlate and validate the solicitations currently reproduced in laboratory tests of thermal fatigue to real solicitations obtained in actual field. The developed methodology includes the evaluation of weather maps from several regions of Brazil to identify the critical conditions. The experimental planning comprehends the evaluation of the ambient temperature, the solar radiation and the temperature of the plastic parts, mounted inside and outside a vehicle.

The Kyoto Protocol established the reduction of pollutant emissions limits for all sectors of industrial economy in 8%, compared to 1990's levels, to be adopted in the period between 2008 and 2012. Since then, the European Union defined a progressive scale for the emission reduction applied to automotive vehicles, monitoring the levels of Nitrogen Oxide (NOx), Hydrocarbons (HC), Carbon Monoxide (CO) and particulate matter (PM). The European Union named the emission levels as EURO, while Brazil has named it's own Tier (PROCONVE). Since 2009, the Brazilian automotive industries are obligated to produce cars attending to the Tier 2 phase for gasoline and flexible engines and Euro 3 for diesel engines, while the countries using benzene and diesel must attend the Euro 3 phase.

Cold start systems provide the introduction of gasoline inside the engine intake system during cold start and warm-up acceleration, as ethanol fuel shows engine operation difficulties at low temperatures. Despite the technological evolution, traditional cold start systems may present problems mainly related to flow control and gasoline distribution to the engine cylinders hindering cold start and warm-up operation with the increasing of emissions levels and fuel consumption. The cold start system used allows for simultaneous gasoline introduction through calibrated orifices in the four conduits of the intake system. Adjustment of gasoline flow is made by an electronic fuel injector. The objective of this work is to analyze numerically and experimentally the gasoline flow in an auxiliary cold start system for vehicles with engines using ethanol or ethanol-gasoline blends (flex fuel).