Analytical Comparison of Real Drive Emissions from Passenger Vehicle at Different Altitude Operation Conditions

As a major checkpoint in worldwide Automotive Emission Regulations, the Real Drive Emission (RDE) has been introduced to regulate the amount of pollutants in real road driving conditions. Such tests depend very much on numerous ambient conditions, in which the altitude of the terrain is one major factor. Among the various vehicle exhaust pollutants, NOx, CO & CO2 have the tendency to vary in connection to the atmospheric ambient conditions where the vehicles are being operated. For an instance, in our targeted case of testing at higher altitudes CO & NOx levels are found to be higher than when tested at normal RDE regulatory altitude limits. As the altitude increases, the amount of oxygen present in the atmosphere decreases, which can cause the combustion process in an internal combustion engine to operate at a lesser efficient stoichiometric composition than at sea level. This will in-turn produce more exhaust emissions as a byproduct of such altered compensative functioning (combustion), which will ultimately lead to elevated levels of harmful pollutants into the atmosphere. Hence, there is a significant need to consider various altitude levels as test zones for possible RDE test condition to be included in the vehicle development. For this proposed study, a calibrated PEMS equipment is being used to perform the on-road RDE test trials in carefully formulated test routes in which 2 different fuel based vehicles were validated such that it satisfies all the necessary test boundary conditions to obtain valid results. The final intended outcome of this study would be to provide an analytical comparison of Real Drive Emission evaluation on passenger vehicles at areas of extended atmospheric & drive conditions which are not generally covered under standard regulation test condition.