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Heavy duty diesel engines are homologated for emissions using engine test dynamometers according to predefined emission cycles. In 2012, it was released in the Brazilian market the first diesel heavy duty vehicles with PROCONVE P7 technology (EURO V). The homologation tests include emission measurement according to stationary cycles (ESC) and also transient tests (ETC). For the ESC emission measurement it is possible to use a passive dynamometer, while the transient test requires an active dynamometer. Uncertainty of measurement is an important matter to get accurate emission data, but there are not many published papers about a method for its calculation related to diesel engine emissions. According to this scenario, this paper presents a method to calculate the uncertainty of measurement of legislated pollutants for diesel engines (CO, NOx, THC and particulate matter).

Experiments in engine test cells are under the influence of several parameters and types of equipment, which may impact the test results. Many variables of interest are derived from the combination of more than one quantity, increasing the results uncertainty of the final reported value. This paper describes a detailed procedure to calculate uncertainty of measurement of emission tests using a FTIR (Fourrier Transformed Infrared) emission analyzer. A Flex-Fuel engine using gasoline and ethanol was tested under different operating conditions on an engine dynamometer equipped with automation system. For each operating condition at least four different measurements were taken. The expanded uncertainty was calculated by the combination of Type A (due to repeatability) and Type B (due to calibration, sensor resolution and others).

The 2005 Brazilian vehicle noise emission limits, together with the Euro III engine technology necessary to attend these limits, set the scene for this paper. In this context, it is important to evaluate the influence of Diesel cetane number on noise emission from Euro III technology vehicles. The vehicle noise emission tests were performed abroad and also in Brazil according to Brazilian norms NBR 8433/1995 (accelerating noise test) and NBR 9714/2000, (stationary noise test) using Euro III engine technology vehicles. The fuels evaluated were representative of Brazilian production and had cetane numbers varying from 42 to 52. The paper shows that there was no significantly correlation between vehicle noise emission and Diesel cetane number, with the vehicles and fuels used.

The worldwide concerns and some countries stricter legislations regarding the CO2 emission of light duty vehicles are motivating new technologies adoption, such as hybrids and electric battery vehicles, and discussions about what fuel economy data comparison between different countries. International discussions were done about the need to reevaluate the existing standardized driving cycles due to large emission and fuel economy differences when compared to the real road values, leading to the creation of a new cycle called WLTC (Worldwide Harmonized Light Duty Vehicle Test Cycle). Light duty vehicle fuel economy tests are usually performed on a chassis dynamometer using standard driving cycles under controlled laboratory conditions. Each country regulation defines the standard cycles used for the fuel economy tests.

Nowadays, due to the global warming questions related to CO2 emissions, many countries legislation lead automotive and fuel industries to search for higher efficiencies in their products. Therefore, new engine technologies and cleaner fuels are being developed and launched in the market. This paper presents a study of efficiencies on chassis dynamometer tests, in order to evaluate vehicle and fuel contributions. Tests were performed using one Brazilian flex fuel vehicle in full load condition at constant speeds to evaluate the losses of each part of the system, such as, wheel, air resistance and powertrain. The vehicle energy parcels were determined. So, it was possible to assess vehicles mechanical losses, aerodynamic losses and also the engine efficiencies.