Detroit Diesel Corporation Research Articles

Effect of hydrogen addition on criteria and greenhouse gas emissions for a marine diesel engine

Abstract Hydrogen remains an attractive alternative fuel to petroleum and a number of investigators claim that adding hydrogen to the air intake manifold of a diesel engine will reduce criteria emissions and diesel fuel consumption. Such claims are appealing when trying to simultaneously reduce petroleum consumption, greenhouse gases and criteria pollutants. The goal of this research was to measure the change in criteria emissions (CO, NO x , and PM 2.5 ) and greenhouse gases such as carbon dioxide (CO 2 ), using standard test methods for a wide range of hydrogen addition rates. A two-stroke Detroit Diesel Corporation 12V-71TI marine diesel engine was mounted on an engine dynamometer and tested at three out of the four loads specified in the ISO 8178-4 E3 emission test cycle and at idle. The engine operated on CARB ultra-low sulfur #2 diesel with hydrogen added at flow rates of 0, 22 and 220 SLPM. As compared with the base case without hydrogen, measurements showed that hydrogen injection at 22 and 220 SLPM had negligible influence on the overall carbon dioxide specific emission, EF CO 2 . However, in examining data at each load the data revealed that at idle EF CO 2 was reduced by 21% at 22 SLPM (6.9% of the added fuel energy was from hydrogen) and 37.3% at 220 SLPM (103.1% of the added fuel energy was from hydrogen). At all other loads, the influence of added hydrogen was insignificant. Specific emissions for nitrogen oxides, EF NO x , and fine particulate matters, EF PM 2.5 , showed a trade-off relationship at idle. At idle, EF NO x was reduced by 28% and 41% with increasing hydrogen flow rates, whilst EF PM 2.5 increased by 41% and 86% respectively. For other engine loads, EF NO x and EF PM 2.5 did not change significantly with varying hydrogen flow rates. One of the main reasons for the greater impact of hydrogen at idle is that the contribution of hydrogen to the total fuel energy is much higher at idle as compared to the other loads. The final examination in this paper was the system energy balance when hydrogen is produced by an on-board electrolysis unit. An analysis at 75% engine load showed that hydrogen production increased the overall equivalent fuel consumption by 2.6% at 22 SLPM and 17.7% at 220 SLPM.

Emissions of PCDD/Fs, PCBs, and PAHs from legacy on-road heavy-duty diesel engines

Exhaust emissions of seventeen 2,3,7,8-substituted polychlorinated dibenzo-p-dioxin/furan (PCDD/F) congeners, tetra–octa PCDD/F homologues, 12 WHO 2005 polychlorinated biphenyl (PCB) congeners, mono–nona chlorinated biphenyl homologues, and 19 polycyclic aromatic hydrocarbons (PAHs) from three legacy diesel engines were investigated. The three engines tested were a 1985 model year GM 6.2J-series engine, a 1987 model year Detroit Diesel Corporation 6V92 engine, and a 1993 model year Cummins L10 engine. Results were compared to United States’ mobile source inventory for on-road diesel engines, as well as historic and modern diesel engine emission values. The test fuel contained chlorine at 9.8ppm which is 1.5 orders of magnitude above what is found in current diesel fuel and 3900ppm sulfur to simulate fuels that would have been available when these engines were produced. Results indicate PCDD/F emissions of 13.1, 7.1, and 13.6pg International Toxic Equivalency (I-TEQ)L−1 fuel consumed for the three engines respectively, where non-detects are equal to zero. This compares with a United States’ mobile source on-road diesel engine inventory value of 946pg I-TEQL−1 fuel consumed and 1.28pg I-TEQL−1 fuel consumed for modern engines equipped with a catalyzed diesel particle filter and urea selective catalytic reduction. PCB emissions are 2 orders of magnitude greater than modern diesel engines. PAH results are representative of engines from this era based on historical values and are 3–4 orders of magnitude greater than modern diesel engines.

Demonstration and evaluation of a retrofit urea-SCR after-treatment system for NOx reduction in marine diesels

A stand-alone retrofit urea-SCR after-treatment system has been developed employing a pre-SCR NOx sensor, exhaust flow measurement, wire mesh mixer, clean-up catalyst, open-loop feed-forward control and stoichiometric NOx reduction logic. Demonstration of the urea-SCR system on a 1991 Detroit Diesel Corporation 12L engine in a West Virginia University (WVU) transient test cell achieved a 50% weighted NOx reduction and zero ammonia slip over the ICOMIA E5 marine cycle. The cost-effectiveness of the urea-SCR system was determined, including a $50 000 capital cost and $2705/t NOx reduced annually, which is consistent with Carl Moyer program estimates.

Testing of a Heavy Heavy-Duty Diesel Engine Schedule for Representative Measurement of Emissions

The Advanced Collaborative Emissions Study (ACES) program required the use of representative heavy-duty diesel engine activity. This need resulted in an engine test schedule creation program, and a schedule of engine modes representative of modern truck usage was developed based on data collected from engines in trucks operated through the heavy heavy-duty diesel truck (HHDDT) chassis schedule. The ACES test schedule included four active modes of truck operation including creep, transient, cruise, and high-speed cruise (HHDDT_S). This paper focuses on Phase 2 of the program, which was to validate and demonstrate the use of the ACES modes in a test cell. Preliminary testing was performed using a 1992 Detroit Diesel Corporation heavy heavy-duty diesel engine (HHDDE) on only the transient mode. On the basis of these results, each mode was modified slightly to suit implementation in a test cell. The locations of “closed throttle” points in the modes were determined through careful examination of the data. These closed throttle points were simulated during testing by adding negative set point torque values to the input file. After modification, all modes were tested during a final ACES modes demonstration period using a 2004 Cummins ISM HHDDE, obtaining three runs for each mode. During testing, carbon monoxide (CO), carbon dioxide (CO2), nitrogen oxides (NOx), particulate matter (PM), and hydrocarbon (HC) emissions were measured, and engine control unit (ECU) data were recorded. The new ACES modes did not adopt the Federal Test Procedure (FTP) regression criteria. New regression criteria for acceptability of a run were determined for each mode using the data obtained during testing.

Impact of military JP-8 fuel on heavy-duty diesel engine performance and emissions

Investigating the impact of jet fuel on diesel engine performance and emissions is very important for military vehicles, due to the US Army Single Fuel Forward Policy mandating that deployed vehicles must refuel with aviation fuel JP-8. There is a known torque and fuel economy penalty associated with the operation of a diesel engine with JP-8 fuel, due to its lower density and viscosity. On the other hand, a few experimental studies have suggested that kerosene-based fuels have the potential for lowering exhaust emissions, especially particulate matter, compared to diesel fuel #2 (DF-2). However, studies so far have typically focused on quantifying the effects of simply replacing the regular DF-2 with JP-8, rather than fully investigating the reasons behind the observed differences. This research evaluates the effect of using JP-8 fuel in a heavy-duty diesel engine on fuel injection, combustion, performance, and emissions, and subsequently utilizes the obtained insight to propose changes to the engine calibration to mitigate the impact of the trade-offs. Experiments were carried out on a Detroit Diesel Corporation (DDC) S60 engine outfitted with exhaust gas recirculation (EGR). The results indicate that torque and fuel economy of diesel fuel can be matched, without smoke or NO x penalty, by increasing the duration of injection to compensate for the lower fuel density. The lower cetane number of JP-8 caused an increased ignition delay and increased premixed combustion, and their cumulative effect led to relatively unchanged combustion phasing. Under almost all conditions, JP-8 led to lower NO x and particulate matter (PM) emissions and shifted the NO x-PM trade-off favourably.

Exhaust emissions from engines of the Detroit Diesel Corporation in transit buses: a decade of trends.

In the U.S.A., exhaust emissions from city buses fueled by diesel are not characterized well because current emission standards require engine tests rather than tests of whole vehicles. Two transportable chassis dynamometer laboratories developed and operated by West Virginia University (WVU) have been used extensively to gather realistic emission data from heavy-duty vehicles, including buses, tested in simulated driving conditions. A subset of these data has been utilized for a comprehensive introspection into the trends of regulated emissions from transit buses over the last 7 years, which has been prompted by continuously tightening restrictions on one hand, along with remarkable technological progress, on the other hand. Two widely used models of diesel engines manufactured by the Detroit Diesel Corporation (DDC) have been selected as a case-study for such an overview, based on full-scale, on-site testing of actual city buses, driven in accordance with the SAE J1376 standard of a Commercial Business District (CBD) cycle. The results provide solid, quantitative evidence that most regulated emissions from engines produced by DDC have declined over the years, especially with the transition from the 6V-92TA to the Series 50 models. This improvement is remarkable mainly for the emissions of particulate matter (PM), that are lower by over 70%, on average, for the Series 50 engines, though the emissions of nitrogen oxides (NOx) exhibit a reversed trend, showing a degradation of about 6%, on average, with the transition from 6V-92TA to the Series 50 engines. The expected trend of decreasing emission levels with the model year of the engine is clear and consistent for particulate matter (PM), hydrocarbons (HC), carbon monoxide (CO), and nitrogen oxides (NOx), starting with the 1990 models, although it is not conclusive for carbon dioxide (CO2) emissions.

BIODIESEL EMISSIONS DATA FROM SERIES 60 DDC ENGINES

This study compared two Detroit Diesel Corporation (DDC) Series 60 DDC engines that were fueled with variousblends of biodiesel and petroleum diesel fuel to gain a deeper understanding of (1) exhaust emissions regulated by theEnvironmental Protection Agency; (2) selected fuel related properties, and (3) power/performance characteristics.The resultsof this study are in general agreement with studies previously conducted on two and four stroke diesel engines. Slight increaseswere noted for Nox exhaust gas emissions, while decreases were noted for THC, CO and particulate matter.

A Rugged and Reliable System for Measuring Engine Crankshaft Speed Fluctuations

A measurement system and the associated signal processing algorithm for accurately determining engine crankshaft speed fluctuations are presented in this work. The main features of the system include ruggedness, simple sensor installation, and high accuracy and resolution. The ruggedness and simplicity of the system are characterized by the use of highly reliable Hall-Effect Transducers (HETs) mounted on the engine flywheel bell housing to sense the passing of flywheel gear teeth. A relatively significant noise component is introduced to the HET measurements by the nonuniform flywheel gear tooth spacings. The high measurement accuracy is achieved by a very computationally efficient signal processing algorithm based on two HET inputs. The advantages of the current system over the single HET systems commonly used in practice are clearly demonstrated through experiments on a Detroit Diesel Corporation 6V-92TA engine.

Using total cycle time for quick response manufacturing

Thomas Group Inc., with offices in Irving, Texas, Detroit, Michigan, Singapore and Frankfurt, Germany, has more than 20 years’ experience of vastly improving client business efficiency through cycle time reduction. This article explains the advantages of moving from a “blame culture” to an interconnected seamless, holistic business approach to widespread and continuous improvement. The concepts of baseline and entitlement performances are explained as well as tools such as time‐based management and treating companion processes. Specific examples are cited for concepts and actual results from Detroit Diesel Corporation are revealed. Finally the actions‐in‐process management system illustrates paths toward reduced cycle time.

Heavy-duty engine exhaust emission tests using methyl ester soybean oil/diesel fuel blends

A model 6V92TA Detroit Diesel Corporation diesel engine (9.0 l) was fueled on blends of 10, 20, 30 and 40% soydiesel/diesel fuel. The engine was tested using the Environmental Protection Agency (EPA) heavy-duty engine test cycle in an EPA certification test cell. A 56.6 m 3/min (2000 cfm) PDP-CVS dilution tunnel, gaseous bench and particulate bench provided full gaseous and particulate emissions data. Fueling with biodiesel/diesel fuel blends reduced particulate matter (PM), total hydrocarbons (THC) and carbon monoxide (CO), while increasing oxides of nitrogen (NO x). The optimum blend of biodiesel and diesel fuel was a 20/80 biodiesel/diesel fuel blend. Retarded fuel injection timing reduced NO x emissions, while CO, THC and PM remained essentially constant with a 20/80 biodiesel/diesel fuel blend.

Exhaust Emissions From Two Intercity Passenger Locomotives

To enhance the effectiveness of intercity passenger rail service in mitigating exhaust emissions in California, the California Department to Transportation (Caltrans) included limits on exhaust emissions in its intercity locomotive procurement specifications. Because there were no available exhaust emission test data on which emission reduction goals could be based, Caltrans funded a test program to acquire gaseous and particulate exhaust emissions data, along with smoke opacity data, from two state-of-the-art intercity passenger locomotives. The two passenger locomotives (an EMD F59PH and a GE DASH8-32BWH) were tested at the Association of American Railroads Chicago Technical Center. The EMD locomotive was eqiupped with a separate Detroit Diesel, Corporation (DDC) 8V-149 diesel engine used to provide 480 V AC power for the trailing passenger cars. This DDC engine was also emission tested. These data were used to quantify baseline exhaust emission levels as a challenge to locomotive manufacturers to offer new locomotives with reduced emissions. Data from the two locomotive engines were recorded at standard fuel injection timing and with the fuel injection timing retarded 4 deg in an effort to reduce NOx emissions. Results of this emissions testing were incorporated into the Caltrans locomotive procurement process by including emission performance requirements in the Caltrans intercity passenger locomotive specification, and therefore in the procurement decision. This paper contains steady-state exhaust emission test results for hydrocarbons (HC), carbon monoxide (CO), oxides of nitrogen (NOx), and particulate matter (PM) from the two locomotives. Computed sulfur dixoide (SO2) emissions are also given, and are based on diesel fuel consumption and sulfur content. Exhaust smoke opacity is also reported.