Air Pollution and Noise Emissions of a Euro5 Diesel Car in Different Testing Environments

This paper presents results of an experimental investigation on a Diesel car, complying with Euro 5 standard, in two testing environments: in laboratory with car installed on a chassis dynamometer bench and on a track. Car was instrumented with a set of sensors for the assessment of NOx emissions, as well as for the evaluation of interior sound quality. Tests were performed in type-approval driving cycle and steady-state conditions, ranging from 10 to 130 km/h. Vehicle emissive behavior was analyzed in function of ambient conditions and engine parameters. At the same time, acoustic signals coming from pressure measurements acquired inside car cabin in correspondence of passengers' ears, were properly processed in terms of quality of the noise. Some of the most commonly used parameters for sound quality analysis were considered, in order to assess the influence of the different testing environments and the vehicle operating conditions on the acoustic comfort perceived by car's occupants. In the work, air and noise emissions data are jointly analyzed and discussed. The analysis will be preparatory for the development of an overall quality index (encompassing both polluting and noise emissions), which may be useful to evaluate the environmental quality of a vehicle and in aiding policy makers in a variety of urban context.