Characterization of Exhaust Emissions from Heavy Duty Diesel Vehicles in the HGB Area (2012)
This technical report discusses the development and study of emission characteristics from a variety of HDDVs in the HGB area. The project focused on understanding and characterizing the HDDV emissions for representative fleets in the HGB area. The research team explored a variety of vehicle fleets and identified the city of Houston (COH) fleet for use in the study. Thirty HDDVs were selected from the COH fleet to represent both high emitter (HE) and non-HE vehicles. A set of 12 HEs identified based on opacity testing, and a randomselection was used for the non-HEs. The research team performed a driving test measuring various parameters such as speed, acceleration, engine load, and in-use emissions. Additionally, they performed an idling emissions test under controlled conditions in an environmental test chamber. The measured emissions were also compared to estimates obtained using the Motor Vehicle Emission Simulator (MOVES). This testing allowed the research team to learn the characteristics of HE emissions and compare them to emissions for the general fleet (non-HEs).