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Currently, fuels development is strongly dependent on experiments. New engines and vehicles simulation methodologies contribute to speed up R & D projects deadlines, as well as reducing costs. This paper presents a modeling methodology for a vehicle deceleration load curve (coast down) prediction and simulations of coast down variations impact on urban and highway autonomies. Two coast down curve mathematical models were successfully developed and validated. The first one, based on vehicles technical specifications and empirical equations, resulted in percent differences up to 9% compared to the experimental results. This is lower than the variation established on coast down standard, which is 15%. The second, generated by regression analysis between other vehicles characteristics versus experimental results of F0 and F2 (coast down curve parameters), resulted in percent differences up to 15%, for six of the eight vehicles.

Through a market analysis, PETROBRAS identified an opportunity to launch a new product dedicated to diesel boats market. This paper describes the activities performed by PETROBRAS research center (CENPES) during the new diesel development: new or improved methodologies to ensure reliable comparative performance, fuel consumption and smoke emissions analysis, with appropriate precision to elucidate differences between the new fuel and the conventional marine diesel. Performance tests were conducted by using radar monitoring. For fuel consumption, constant engine speed tests were made, with fuel flow measurement and acquisition. Smoke tests were performed using a total flow smokemeter, installed directly on the exhaust gas pipe. Results showed that, because of its special characteristics, the new diesel allows performance gains up to 6% and smoke emissions reduction up to 83%. Fuel consumption remains in the same level of regular marine diesel.