Bruno Vieira Bertoncini

Simulation of the impact on carbon monoxide concentration resulting from replacing a signalised intersection with a roundabout

This work studies the impact of the substitution of a traffic light for a modern roundabout on carbon monoxide concentration. The estimate of CO concentration is made by means of the CAL3QHC dispersion model, considering only passenger vehicles as emitting sources. Local traffic and meteorological parameters had been adopted and the emission factors had been estimated using CMEM emission model. The maximum observed values in eight different wind directions had been compared, considering both moving and queued vehicles. The adopted model showed that the maximum concentrations of CO in the roundabout scenario were about 50% of the obtained values with the use of the signalised intersection. Concentration maps analysis demonstrated that not only the maximum values are higher in the case of the traffic light, but the area of the concentration curves is larger. These analyses are important for proper environmental management and contribute to traffic engineers seeking environmentally sustainable solutions.

Analysis of emission models integrated with traffic models for freight transportation study in urban areas

In the present work, two dynamic emission models integrated to traffic simulators were analysed: Panis et al. and EnViver integrated to traffic simulators AIMSUN and VISSIM, respectively. These models were selected due to their capacity to execute emission estimations of particulate matter (PM), a pollutant found in the incomplete combustion in diesel cycle engines and extremely harmful to human health and because of their negative impact was the study object of this paper. Estimated data were confronted with collected data emission in the field through a collecting procedure built by Dias et al. (2015) from a typical urban service vehicle of Fortaleza City - CE, aiming to verify the model that estimated particulate matter data emission closer to the reality of vehicles studied in this research. The selected models can estimate the main rates of particulate matter or originated in urban freight transport. However, the model proposed by Panis et al. was considered more appropriate in the representation of this phenomenon.