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An Andersen Impactor was used to collect particulate samples in both the undiluted and diluted exhaust from a Caterpillar 3150 diesel engine operated on the EPA 13-mode cycle. A total of 24 samples were examined using the transmission electron microscope and approximately 300 photomicrographs were taken. The microscope analysis and photomicrographs revealed details concerning the physical characteristics of the particulate and permitted a direct visual comparison of the samples collected. The photomicrographs were used to obtain diameter measurements of the basic individual spherical particles that comprise the much larger aggregates/agglomerates. Nearly 11,000 basic particles were measured and the observed range of diameters was 70-1200 Å. The mean particle diameters in the undiluted and diluted exhaust samples were 479 Å and 436 Å respectively. respectively. A respectively. 436 A respectively.

Diesel smoke measurements were made over a broad range of smoke intensities with seven different commercially available smokemeters using a 4-cycle engine and a 2-cycle engine operated under steady-state conditions on two fuels of different smoking tendencies. Exhaust soot concentrations were also measured by two filtering methods, and smoke was rated visually by two trained raters. Correlations among the smokemeter readings did not differ with either fuel or engine. A nomograph correlating smokemeter readings was prepared, and agreement with published data appears generally good except for high readings from one continuous filtering smokemeter exposed to high sampling pressure, and unexplained low readings from a light-dispersion meter. The CRC Smokemeter Group believes these correlations, with the exceptions mentioned, give a firm basis for comparing measurements made with different smokemeters.

Methods for sampling, handling and measuring emissions of particulates, hydrocarbons, carbon monoxide, carbon dioxide, oxides of nitrogen and oxygenated compounds in the exhaust of aircraft turbine engines were evaluated in a cooperative experimental program conducted by industry and government at the Naval Air Propulsion Test Center in September, 1969. Non-dispersive infrared (NDIR) instruments and a Fisher chromatographic partitioner were both well suited for measuring CO and CO2. Some additional development is needed in NDIR instruments and the phenol disulphonic acid (PDS) method for measuring NOx and in the 3-methyl-2-benzothiazolinone hydrazine hydrochloride (MBTH) method for measuring oxygenated compounds.

In 1972 and 1973, the CRC-APRAC Program Group on Diesel Exhaust carried out a fourth program to evaluate techniques for measuring concentration of hydrocarbon in diesel exhaust. The first two programs were conducted in 1967 and 1968. In them, a single cylinder diesel engine was shipped among 13 laboratories and each laboratory measured hydrocarbon emissions by their own method. Agreement among laboratories (instruments) was poor in both programs. The third program was conducted in 1970 at one laboratory on one engine. This time, agreement among instruments was much improved from the earlier programs. The fourth program was conducted to confirm these later results. In it, a multi-cylinder diesel generating set was circulated among 15 participating laboratories, and each laboratory measured exhaust hydrocarbon by methods that complied with SAE Recommended Practice J215, “Continuous Hydrocarbon Analysis of Diesel Exhaust.”

Research octane ratings do not adequately define the antiknock performance of gasolines in cars on the road; gasoline sensitivity, composition, and other fuel properties also have effects. Specific correlation equations can express the effects of the fuel properties, but a different equation is needed for each car and speed. With the aid of simple statistics, the different equations can be combined to yield the Customers' Antiknock Rating, or CAR. The CAR of a gasoline is uniquely related to the percentage of cars the gasoline will power without knocking; even in simplified form, CAR is much better than Research rating. The use of CAR improves comparisons of gasolines, quality control, evaluations of processes, and projections of future antiknock quality. Although the CAR is more complex than Research rating, it has many advantages; we are using it and hope the automotive and petroleum industries will consider adopting something like it in the future.

A 2007 Cummins ISL 8.9L direct-injection common rail diesel engine rated at 272 kW (365 hp) was used to load the filter to 2.2 g/L and passively oxidize particulate matter (PM) within a 2007 OEM aftertreatment system consisting of a diesel oxidation catalyst (DOC) and catalyzed particulate filter (CPF). Having a better understanding of the passive NO₂ oxidation kinetics of PM within the CPF allows for reducing the frequency of active regenerations (hydrocarbon injection) and the associated fuel penalties. Being able to model the passive oxidation of accumulated PM in the CPF is critical to creating accurate state estimation strategies. The MTU 1-D CPF model will be used to simulate data collected from this study to examine differences in the PM oxidation kinetics when soy methyl ester (SME) biodiesel is used as the source of fuel for the engine.

The effect of the use of a manganese-copper fuel additive with a Corning EX-47 particulate trap on heavy-duty diesel emissions has been investigated; reductions in total particulate matter (70%), sulfates (65%), and the soluble organic fraction (SOF) (62%) were measured in the diluted (15:1) exhaust and solids were reduced by 94% as measured in the raw exhaust. The use of the additive plus the trap had the same effect on gaseous emissions (hydrocarbons and oxides of nitrogen) as did the trap alone. The use of the additive without the trap had no effect on measured gaseous emissions, although sulfate increased by 20%. Approximately 50% of the metals added to the fuel were calculated to be retained in the engine system. The metals emitted by the engine were collected very efficiently (>97%) by the trap even during regeneration, which occured 180°C lower when the additive was used.

A diesel fuel classification is proposed that is compatible with fuel availability and that would enable consumers to better choose the optimum fuel for any use. It includes four, well-defined grades of fuel: I - A volatile, very high quality fuel with excellent combustion characteristics especially suited for use at low temperatures. II - A high quality fuel for general use in vehicles. III - A good quality fuel for general use in vehicles. IV - A fuel for nonvehicle use. Industry-wide adoption of this classification is recommended, and a proper first step would be revision of the ASTM D 975 classification of diesel fuel.

Protocols for sampling and analysis of particulate and gaseous-phase diesel emissions were developed to characterize the chemical and biological effects of using ceramic traps as particulate control devices. A stainless-steel sampler was designed, constructed, and tested with XAD-2 sorbent for the collection of volatile organic compounds (VOC). Raw exhaust levels of TPM and SOF and mutagenicity of the SOF and VOC were all reduced when the traps were used. Hydrocarbon mass balances indicated that some hydrocarbons were not collected by the sampling system and that the proportions of collected SOF and VOC were altered by the use of the traps. SOF hydrocarbons appeared to be derived mainly from engine lubricating oil; VOC hydrocarbons were apparently fuel-derived. There was no apparent effect on SOF mutagenicity due to either sampling time or reexposure of particulate to exhaust gases.

The CRC-APRAC CAPI-1-64 Odor Panel was formed in 1973 to assess an instrumental measurement system for diesel exhaust odor (DOAS) developed under CRC-APRAC CAPE-7-68 by Arthur D. Little, Inc. Four cooperative studies were conducted by nine participating laboratories using common samples. The objectives of these studies were to define the DOAS system variables and to validate and improve the sampling and collection procedures. A fifth study, serving as a review of each analysis step, showed that analysis of common derived odorant samples could be conducted within acceptable limits by the participating laboratories. Three in-house sampling system design and operating parameter studies were conducted simultaneously with the cooperative work. The combined findings from the in-house and cooperative studies led to a tentative recommended procedure for measuring diesel exhaust odor.

Methods available for measuring hydrocarbons in diesel exhaust were evaluated by the CRC-APRAC Program Group on Diesel Exhaust Composition during 1967-1970. Early tests showed distressingly large variations from instrument to instrument and undesirably large variations among repeated measurements by one instrument. Instrument quality and operator competence were better in later tests and agreement among instruments was relatively good and errors within instruments were small. Current techniques appear acceptable for engineering measurements. No further cooperative work is planned by CRC at present, but techniques for measuring hydrocarbons in diesel exhaust will be reappraised periodically.

This is the fourth in a series of tests conducted as a Coordinating Research Council cooperative program to evaluate the measurement methods used to analyze diesel exhaust gas constituents. A multi-cylinder engine was circulated to 15 participants who measured emissions at three engine conditions. All 15 participants measured nitric oxide and carbon monoxide with several laboratories measuring nitric oxide by both NDIR (Non-Dispersive Infrared) and CHEMI (Chemiluminescence). Some participants also measured carbon dioxide, nitrogen dioxide, oxygen, and unknown span gases. The test results are compared with the Phase III cooperative tests which involved simultaneous measurement of emissions by participants. The precision of the results was poorer in Phase IV than Phase III.

A Coordinating Research Council cooperative program was conducted to evaluate the measurement methods used to analyze nitric oxide and carbon monoxide in diesel exhaust. Initially, a single-cylinder test engine was circulated among participants with poor results. Tests were then conducted at one site using a multicylinder diesel engine. Six organizations participated in the program. Exhaust analyses were conducted at steady-state engine conditions and on a 3 min cycle test. Span gases of unknown concentration were also analyzed. The participants results varied but averaged less than ±5% standard deviation both within (repeatability) and among (reproducibility) the instruments. The short cycle test was in good agreement with the steady-state measurements. No significant difference in the use of Drierite, nonindicating Drierite, or Aquasorb desiccants was evident in sampling system tests.

A cooperative test program was conducted by the CRC-APRAC CAPI-1-64 Composition of Diesel Exhaust Program Group to evaluate the technical aspects of a proposed EPA recommended Heavy Duty Diesel Emission Measurement and Test Procedure. The proposed changes affected the sampling configurations and the types of instruments used. Six participants studied the effects of a number of variables on the proposed changes and evaluated some alternative systems that included both CHEMI and NDIR instruments. The tests were conducted at one site using a multi-cylinder engine operating on the 13-Mode Cycle. Equivalency of systems was demonstrated and the best performance was obtained with a special NDIR system.

A microprocessor controlled lubricating oil cooling system of truck diesel engine was designed to minimize the sump oil temperature fluctuation during start-up and nonsteady engine operations. Model reference adaptive control method is utilized in the control system design. The analysis involved in the design of the microprocessor controlled oil cooling system, and the applications of a special vehicle-engine-cooling system (VEC) computer simulation code in the implementation and testing of the model reference adaptive control strategy are described. Using the VEC simulation code, the performance of the microprocessor controlled oil cooling system and the conventionally controlled oil cooling systems were compared for the ATB, temperature disturbances, and cold weather transient tests. An explanation of each test, as well as a review of the results of comparison tests are presented.

A thermal management system for heavy duty diesel engines is presented for maintaining acceptable and constant engine temperatures over a wide range of operational conditions. It consists of a computer controlled variable speed coolant pump, a position controlled thermostat, and a model-based control strategy. An experimentally validated, diesel engine cooling system simulation was used to demonstrate the thermal management system's capability to reduce power consumption. The controller was evaluated using a variety of operating scenarios across a wide range of loads, vehicle speeds, and ambient temperatures. Three metrics were used to assess the effects of the computer controlled system: engine temperature, energy savings, and cab temperature. The proposed control system provided very good control over the engine coolant temperatures while maintaining engine metal temperatures within a desired range.

The amount of vapors lost from an automobile fuel system is determined from changes in density of the gasoline as it weathers. The composition of the vapors lost is calculated from the initial composition of the fuel by simple distillation theory. The techniques are simple, precise, and generally applicable.

A computer simulation program was developed to simulate the thermal responses of an on-highway, heavy duty diesel powered truck in transient operation for evaluation of cooling system performance. Mathematical models of the engine, heat exchangers, lubricating oil system, thermal control sensors (thermostat and shutterstat), auxiliary components, and the cab were formulated and calibrated to laboratory experimental data. The component models were assembled into the vehicle engine cooling system model and used to predict air-to-boil temperatures. The model has the capability to predict real time coolant, oil and cab temperatures using vehicle simulation input data over various routes.

A quasi-steady 1-dimensional computer model of a catalyzed particulate filter (CPF) capable of simulating active regeneration of the CPF via diesel fuel injection upstream of a diesel oxidation catalyst (DOC) or other means to increase the exhaust gas temperature has been developed. This model is capable of predicting gaseous species concentrations (HC's, CO, NO and NO2) and exhaust gas temperatures within and after the CPF, for given input values of gaseous species and PM concentrations before the CPF and other inlet variables such as time-varying temperature of the exhaust gas at the inlet of the CPF and volumetric flow rate of exhaust gas.

Numerical modeling of aftertreatment systems has been proven to reduce development time as well as to facilitate understanding of the internal physical and chemical processes occurring during different operating conditions. Such a numerical model for a catalyzed diesel particulate filter (CPF) was developed in this research work which has been improved from an existing numerical model briefly described in reference. The focus of this CPF model was to predict the effect of the catalyst on the gaseous species concentrations and to develop particulate matter (PM) filtration and oxidation models for the PM cake layer and substrate wall so as to develop an overall model that accurately predicts the pressure drop and PM oxidized during passive oxidation and active regeneration. Descriptions of the governing equations and corresponding numerical methods used with relevant boundary conditions are presented.