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In order to control diesel engine emission, several after-treatment technologies have been studied and developed to reduce particulate matter (PM) and nitrogen oxides. Such reduction is making it hard to measure the mass of such pollutants. In the present study, a new method to analyze nitrogen compounds in vehicle particulate has been described. The method is based on the technique for separate analysis of SOF, soot and sulfates in particulate, which has been previously reported by the authors. The new method utilizes oxidation process in a furnace at high temperature and a chemiluminescence detector (CLD) to measure generated NO and NO2. In this paper, principle and concept of the method has been described. In addition, feasibility of the method for analyzing nitrogen compounds in vehicle PM has been discussed, with practical experiments using modeled samples and actual particulate.

The performance of a soft ionization mass spectrometer (MS) has been investigated using nearly one hundred hydrocarbon components and nine inorganic components. Based on a list of typical hydrocarbon emissions from automotive exhaust, synthesized samples have been used to discuss the cross-sensitivity of the target components. The system has been shown to measure hazardous air pollutants (HAPs) such as 1,3-butadiene, benzene and toluene in the vehicle exhaust. As a result, the technique will prove to be very useful in emissions monitoring in the development of low emissions vehicles.

The next generation of diesel engines will require substantial reductions in particulate matter (PM) emissions. In addition to strict regulations, one of the major problems in the development is the lack of sophisticated real-time PM analyzers. The current PM measurement technology consists of a dilution tunnel and filter weighing technique that was developed before the 1980s.(1) Such technology has reached its limit for today's diesel exhaust monitoring requirements in terms of response time and sensitivity. A flame ionization detector (FID), commonly used for measuring hydrocarbons, is proposed as a new analyzer for PM. In the past, spike signals observed from the FID when measuring diesel exhaust have been considered noise and a lot effort has been spent to reduce such interference from the slower FID signal. However, given a fast response time FID, these spike signals could be used to represent PM concentration in the sample.

A high speed gas chromatography system has been developed for automotive emissions measurement. The system is capable of quantifying hydrocarbons from C2 to C12 compounds. The separation time required for an analysis is only five minutes. Major technical challenges were (1) tandem quick heat cold traps, (2) four parallel ovens design, and (3) the mid-point back flush technique. Demonstrations of the system have been done using FTP75 cold transient phase. The results indicate that the system is well suited for hydrocarbon speciation measurement with very simple and quick operations.

The objective of the work was to develop a fast response infrared analyzer that makes possible the cyclic measurement of exhaust gas concentrations from internal combustion engines. The new analyzer achieves T90 response time of less than 30 milliseconds and is capable of measuring CO, CO2 and HC (Hydrocarbons) simultaneously. Another feature of the analyzer is its' capability to measure simultaneously from multiple sample points, i.e., one optical bench with a maximum of four sample cells can measure CO, CO2 and HC simultaneously from four different sources. Results from a multiple cylinder engine show that this analyzer can be an effective tool for analysis and diagnosis of internal combustion engine exhaust products.

Distribution of injected fuel droplets, total hydrocarbon concentration and soot concentration in the combustion chamber of a diesel engine with a swirl chamber have been measured microscopically with regard to the time and the space by means of optical method. As a result of this study, effect of the swirl flow on atomized droplet distribution, relation between the droplets and hydrocarbon concentration, and relation between the change in concentration gradient of hydrocarbon with the time and the velocity of the swirl flow, and effect of non-luminous flame on the time of heat release rate raising period have been obtained. And from spatial distributions of hydrocarbon concentration, soot concentration, and local temperature in the combustion chamber at each time, the locational characteristics of soot generation are clarified. Further, effects of hydrocarbon and local temperature on soot generation have been considered.

This report describes a new, maintenance-free exhaust gas analysis system for automobile quality control. It incorporates non-dispersive infrared. (NDIR) gas analyzers employing a cross-flow modulation method which provides virtually drift-free performance and eliminates the need for optical adjustment, Analyzer modulation is by means of alternating the flow of sample gas and reference gas into two cells with a rotary valve of simple construction. Microcomputers are used for system control and to process the data. This system measures oxides of nitrogen (NOx), total hydrocarbon (THC) and carbon monoxide/dioxide (CO/CO2) with three analyzers. Full scale ranges of 50 ppm for NOx and 20 ppm for THC are feasible with cells merely 35 mm long. In each case the signal-to-noise ratio is 100. In actual operation, the system drift was so low that it required no span calibration over a period of three months.