Chassis Test Cycles for Assessing Emissions from Heavy Duty Trucks

Clark, Nigel N.; McKain, David L.; Messer, J; Lyons, Donald W.

doi:10.4271/941946

Cited by 29 publications

(21 citation statements)

References 3 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The bus was tested on the central business district (CBD) Cycle, 4 and the tractor truck was tested on the Truck-CBD Cycle (also called the Modified CBD Cycle). 5 The Truck-CBD Cycle has slower acceleration ramps so that a vehicle with a lower power-to-weight ratio and with an unsynchronized manual transmission (tractor truck) can follow the scheduled speed.…”

Section: Factors Affecting Heavy-duty Diesel Vehicle Emissionsmentioning

confidence: 99%

Factors Affecting Heavy-Duty Diesel Vehicle Emissions

Clark

Kern

Atkinson

et al. 2002

Journal of the Air & Waste Management Association

View full text Add to dashboard Cite

Societal and governmental pressures to reduce diesel exhaust emissions are reflected in the existing and projected future heavy-duty certification standards of these emissions. Various factors affect the amount of emissions produced by a heterogeneous charge diesel engine in any given situation, but these are poorly quantified in the existing literature. The parameters that most heavily affect the emissions from compression ignition engine-powered vehicles include vehicle class and weight, driving cycle, vehicle vocation, fuel type, engine exhaust aftertreatment, vehicle age, and the terrain traveled. In addition, engine control effects (such as injection timing strategies) on measured emissions can be significant. Knowing the effect of each aspect of engine and vehicle operation on the emissions from diesel engines is useful in determining methods for reducing these emissions and in assessing the need for improvement in inventory models. The effects of each of these aspects have been quantified in this paper to provide an estimate of the impact each one has on the emissions of diesel engines.

show abstract

Section: Factors Affecting Heavy-duty Diesel Vehicle Emissionsmentioning

confidence: 99%

Factors Affecting Heavy-Duty Diesel Vehicle Emissions

Clark

Kern

Atkinson

et al. 2002

Journal of the Air & Waste Management Association

View full text Add to dashboard Cite

show abstract

“…Class 8 trucks and tractors, particularly those with unsynchronized manual transmissions, are generally unable to meet the acceleration requirements of the Central Business District cycle (which appears in SAE recommended practice J1376) that is commonly used for transit buses. To satisfy the need for a cycle for heavy truck testing, Clark, et al [11] proposed a "WVU 5 peak truck cycle" which was subsequently used by the Transportable Laboratories. The cycle covers a distance of 5 miles.…”

Section: Transportable Laboratoriesmentioning

confidence: 99%

On-Road Use of Fischer-Tropsch Diesel Blends

Clark¹,

Gautam²,

Lyons³

et al. 1999

SAE Technical Paper Series

Self Cite

View full text Add to dashboard Cite

Alternative compression ignition engine fuels are of interest both to reduce emissions and to reduce U.S. petroleum fuel demand. A Malaysian Fischer-Tropsch gas-to-liquid fuel was compared with California #2 diesel by characterizing emissions from over the road Class 8 tractors with Caterpillar 3176 engines, using a chassis dynamometer and full scale dilution tunnel. The 5-Mile route was employed as the test schedule, with a test weight of 42,000 lb. Levels of oxides of nitrogen (NO x ) were reduced by an average of 12% and particulate matter (PM) by 25% for the Fischer-Tropsch fuel over the California diesel fuel. Another distillate fuel produced catalytically from Fischer-Tropsch products originally derived from natural gas by Mossgas was also compared with 49-state #2 diesel by characterizing emissions from Detroit Diesel 6V-92 powered transit buses, three of them equipped with catalytic converters and rebuilt engines, and three without. The CBD cycle was employed as the test schedule, with a test weight of 33,050 lb. For those buses with catalytic converters and rebuilt engines, NO x was reduced by 8% and PM was reduced by 31% on average, while for those buses without, NO x was reduced by 5% and PM was reduced by 20% on average. It is concluded that advanced compression ignition fuels from non-petroleum sources can offer environmental advantages in typical line haul and city transit applications.

show abstract

“…The same database gave rise to a chassis test, the Urban Dynamometer Driving Schedule for Heavy-Duty Vehicles (Test D), but Dietzman and Warner-Selph 4 found that the emissions for the engine and chassis tests did not match well in units of grams of pollutant per kilogram of fuel used. A wide variety of other heavy-duty chassis test schedules exist [5][6][7][8][9][10] but are unrelated to the FTP. Previously, we proposed a chassis mimicry of the FTP using an energy conservation method, 11 which was subsequently used as a Road Certification Test.…”

Section: Literature Reviewmentioning

confidence: 99%

A Chassis Test Procedure to Mimic the Heavy-Duty Engine Transient Emissions Certification Test

Clark

McKain

2001

Journal of the Air & Waste Management Association

Self Cite

View full text Add to dashboard Cite

In-use emissions from vehicles using heavy-duty diesel engines can be significantly higher than the levels obtained during engine certification. These higher levels may be caused by a combination of degradation of engine components, poor engine maintenance, degradation or failure of emissions after-treatment devices, and engine and emissions system tampering. A direct comparison of in-use vehicle emissions with engine certification levels, however, is not possible without removing an engine from the vehicle in order to perform engine dynamometer emissions testing. The goal of this research was to develop a chassis test procedure that mimics the engine performance, and as such the expected emissions levels, from the engine certification emissions test prescribed in the U.S. Code of Federal Regulations. Emissions measurements were taken from two engines during testing on an engine dynamometer using the transient heavy-duty Federal Test Procedure (FTP). Additionally, each engine was installed in an appropriate vehicle, and emissions measurements were taken using a chassis dynamometer while employing a vehicle driving schedule IMPLICATIONS At present, it is difficult to determine how engines degrade in real use because they are certified for emissions independently of the vehicle, and are seldom removed for retesting. This research has provided a methodology for testing a whole vehicle, with a single gear selected, in a fashion that causes the engine to follow the engine test certification procedure as closely as possible. The results show a strong correlation between engine-and chassismeasured results for NO x , so that engines with high NO x emissions can be identified without removing the engine from the vehicle if this approach is used. Deterioration of NO x emissions can therefore be quantified for a fleet. Data show that using this approach to quantify PM emission is less precise, and that the chassis-based approach may be limited to finding only "super-emitters" if applied to PM compliance.intended to match closely the instantaneous torque and speed schedule of the engine FTP.Engine and chassis testing was performed with the engines in stock (unmodified) condition as well as in several modes to simulate either tampered or poorly maintained conditions. The use of a chassis test as a predictive tool for determining whether an engine in a vehicle would pass the engine certification test has proven to be worthwhile. Analysis of the data shows that identification of chassis-mounted engines with NO x emissions above certification levels is possible by employing engine-specific correction factors. In the case of PM emissions, significant data scatter allowed only the identification of gross PM emitters. Engine tampering and poor maintenance can raise PM and NO x emissions, and these increases can be correctly identified by a chassis test. Analysis of chassis and engine CO and HC emissions did not reveal a strong enough correlation to warrant the use of the chassis test for emissions screening of these two po...

show abstract

Chassis Test Cycles for Assessing Emissions from Heavy Duty Trucks

Cited by 29 publications

References 3 publications

Factors Affecting Heavy-Duty Diesel Vehicle Emissions

Factors Affecting Heavy-Duty Diesel Vehicle Emissions

On-Road Use of Fischer-Tropsch Diesel Blends

A Chassis Test Procedure to Mimic the Heavy-Duty Engine Transient Emissions Certification Test

Contact Info

Product

Resources

About