Study of Nano Particle Emissions and It's Metrices for Diesel 4-Wheelers Evaluation of Vehicle Categories, Models and Model Years at Different Fuel Levels

In recent studies, the health implications of ultra fine particle emissions from vehicles have been investigated in a number of international studies. The adverse health effects are not only dependent on total particulate mass but also on other attributes including size, number and surface area of the particles. These ultra fine particles cause more adverse effect than larger particles. With this need UNECE GRPE had launched a Particulate Measurement Program (PMP) to formulate the regulation to control both particulate mass and number of ultra fine particles. These new regulations are applicable to the diesel and gasoline direct injection passenger cars and heavy duty engines of Euro-V/VI technology. However, at present the other vehicle categories and alternate fuels are not been covered. Limited experiments have been carried-out on the in-use vehicles which are with old technologies. It is essential to understand the particle number, size and their other metrices as they play significant role to the environmental pollution. This paper present the work carried-out on the measurement of nano particle emissions with the test setup conforming to GRPE-PMP requirements. This paper focuses specifically on in-use 4-wheeler diesel passenger cars and multiutility vehicles. The test matrix formulated is based on the Design of Experiment including 3 vehicles of BS-III technology, 6 vehicles of BS-II and 3 vehicles of BS-I technology, out of these total 12 vehicles, 9 Nos. were passenger cars and 3 were multiutility vehicles. These vehicles are of 3 different model years viz. 1996-2000, 2001-2005 and post 2005, and tested on 4 different levels of diesel fuels viz. BS-III, Euro-II, III and IV. This paper discusses the findings of analysis of Particulate matter PM2.5 measured on the Modified Indian driving cycle for 4-wheelers and particle number measured by using Condensation Particle Counter (CPC) and Volatile Particle Remover (VPR). The other metrices of nano particles measured by Engine Exhaust Particle Sizer (EEPS) are size, surface and volume. Further chemical analysis of PM is carried out to measure various non-regulatory pollutants like Soluble Organic Fraction (SOF), Inorganic Fraction (IOF), Poly-Aromatic Hydrocarbons (PAH), Aldehydes and Ketones, 1-3 butadiene and benzene. Experimental data analyzed by using statistical techniques reveal that total PM2.5 measured in g/km and Particle Number (PN) expressed in km-1, both are significant over vehicle models and model years for all tested diesel vehicles. The particle number significantly differs for the model years and it shows decreasing trend. Chemical speciations carried out for PM2.5 shows that SOF, IOF and PAH are the major contributors for the total particulate matter.