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The advanced development of a previous in-use emissions measurement system developed at the University of Alberta, has been used to illustrate the challenges in accurately measuring real-time mass emissions of NOx, with specific attention given to the issue of sensor time resolution. An analysis of the alignment of vehicle and emissions data has shown constant value time shifting of remote emissions sensor data, to match vehicle data, as the most accurate method for synchronization. Although variable time shifting routines theoretically determine alignment time more accurately, the variable shifting of slow response sensor data has shown an added smearing effect to time shifted remote analyzer data. The effect of sensor response time on accuracy of mass emission rates, has shown that slow response remote emissions sensors are under predicting the total emissions produced by vehicles.

As a first step toward better understanding of the effects of flame stretch on combustion rate in SI engines, the burning velocity of a premixed, spherical, laminar methane-air flame propagating freely at standard temperature and pressure was investigated. The underlying un-stretched burning velocity was computed using CHEMKIN 3.7 with GRI mechanism, while the Lewis number and subsequently the Markstein length were deduced theoretically. The burning velocity of the freely growing flame ball was calculated from the un-stretched burning velocity with curvature and stretch effects accounted via the theoretically deduced Markstein length. For the positive Markstein length methane-air flame, flame stretching reduces the burning velocity. Therefore, the burning velocity of a spark-ignited flame starts with a value lower than, and increases asymptotically to, the underlying un-stretched burning velocity as the flame grows.

Biomass is regarded as a renewable resource for upgrading to solid or liquid fuels or for electricity generation. Because its energy density is very low compared to petroleum or coal, the cost of transporting biomass is a significant part of the total biomass cost. For this reason it is usually regarded as a local resource. However, appropriate logistic systems may allow collection of biomass over a large geographical area, thus making it possible to consider efficient, large scale energy conversion systems. For areas without significant water transportation, the basic choices are between truck-based, train-based and pipeline transportation. Previous work has shown that pipeline transport is not effective for biomass delivery due to uptake of carrier fluid (water or oil) by the biomass. Hence, the choice becomes one between train and truck transport.