Search Results

The connection between low rolling resistance tires and fuel consumption is now well established and has been successfully modeled. Previous studies have shown that fuel savings can be predicted by an empirical law tying the difference in rolling resistance force to a difference in fuel consumption while still accounting for the resulting engine efficiency change. However, accurately evaluating fuel savings in real conditions remains a crucial issue, as test uncertainty is generally close to the order of magnitude of the consumption difference. This paper proposes an analytical approach to measuring fuel economy. The test is conducted on an outdoor track using two identical vehicles at a single stabilized speed. The vehicle positions are measured by GPS devices and the absolute fuel consumption of each engine is measured with flowmeters. Specific attention is paid to numerous external parameters that influence fuel consumption, in order to minimize test dispersion.

Goodyear and Michelin formed a joint venture in June of 2000 to develop run flat technology and accelerate the introduction of innovative tire systems. With the run flat segment of the tire market on the verge of rapid growth, potentially involving a number of varied technical approaches, the need for global standards was soon recognized. The joint venture has taken the lead in the effort to establish the standards. The paper gives background on run flat tires and contrasts the widely varying service requirements in different parts of the world. Both vehicle manufacturers and consumers will benefit from these new tire system standards.

The purpose of the 4-SPACE (4-Stroke Powered gasoline Auto-ignition Controlled combustion Engine) industrial research project is to research and develop an innovative controlled auto-ignition combustion process for lean burn automotive gasoline 4-stroke engines application. The engine concepts to be developed could have the potential to replace the existing stoichiometric / 3-way catalyst automotive spark ignition 4-stroke engines by offering the potential to meet the most stringent EURO 4 emissions limits in the year 2005 without requiring DeNOx catalyst technology. A reduction of fuel consumption and therefore of corresponding CO2 emissions of 15 to 20% in average urban conditions of use, is expected for the « 4-SPACE » lean burn 4-stroke engine with additional reduction of CO emissions.

In a context of a renewable and sustainable progress in the automotive industry where fuel and respect for the environment are in the middle of all concerns, energy efficient tires could play a significant role in saving money, limiting greenhouse gases and contributing to reduced local pollution. Using simulation, this paper establishes a simple law to predict fuel savings between two tire configurations, which appear to be almost independent of the usage and which depend on the difference of rolling resistance coefficients, the actual weight of the vehicle and the fuel type. This approach has been evaluated in practice for passenger car tires fitted on one gasoline and one Diesel Midsize car by performing rolling resistance tests, coast down tests, fuel consumption tests at constant speed and emissions recorded on a test bench.