Startup and Idle Emissions Analysis of a 2009 VW Jetta Using PEMS SemtechD

2012 ◽  
Author(s):  
Michael V. Johnson ◽  
Samuel Duncan ◽  
Steven S. McConnell
Keyword(s):  
Fuel Consumption ◽  
Measurement System ◽  
Catalytic Converter ◽  
Cold Start ◽  
Idle Time ◽  
Initial Assessment ◽  
Ambient Temperatures ◽  
Time Period ◽  
Startup Time ◽  
Total Hydrocarbons

A 2009 Volkswagen Jetta was tested using a Portable Emissions Measurement System (PEMS) SemtechD emissions analyzer to determine when the emissions and fuel consumption will be the smallest in regards to startup vs. idle emissions. An idle time equivalent was calculated to determine when idle emissions became equal to startup emissions at four different ambient temperatures for a cold start. The mass of Total Hydrocarbons (THC) emitted limited the idle time equivalent to less than the startup time for all ambient temperatures. The temperature of the Catalytic Converter (CC) was monitored to determine how quickly the car cools down and therefore, how beneficial it is to turn the car off after a certain time period. For the temperature range tested, it was more beneficial for reduced emissions to turn off the car compared to idling by a factor of at least four. The data suggests a trend that idling would never be the best option; however, more testing needs to be done with a greater range of CC cool down temperatures to confirm this initial assessment.

Influence of Low Ambient Temperatures on the Exhaust Gas and Deposit Composition of Gasoline Engines

2021 ◽  
pp. 1-11
Author(s):  
Dominik Appel ◽  
Fabian P. Hagen ◽  
Uwe Wagner ◽  
Thomas Koch ◽  
Henning Bockhorn ◽  
...  
Keyword(s):  
Internal Combustion Engines ◽  
Gasoline Engine ◽  
Cold Start ◽  
Operating Conditions ◽  
Pollutant Emissions ◽  
Ex Situ ◽  
Exhaust Gas ◽  
Gasoline Engines ◽  
Ambient Temperatures ◽  
Aftertreatment Systems

Abstract To comply with future emission regulations for internal combustion engines, system-related cold-start conditions in short-distance traffic constitute a particular challenge. Under these conditions, pollutant emissions are seriously increased due to internal engine effects and unfavorable operating conditions of the exhaust aftertreatment systems. As a secondary effect, the composition of the exhaust gases has a considerable influence on the deposition of aerosols via different deposition mechanisms and on fouling processes of exhaust gas-carrying components. Also, the performance of exhaust gas aftertreatment systems may be affected disadvantageously. In this study, the exhaust gas and deposit composition of a turbocharged three-cylinder gasoline engine is examined in-situ upstream of the catalytic converter at ambient and engine starting temperatures of -22 °C to 23 °C using a Fourier-transform infrared spectrometer and a particle spectrometer. For the cold start investigation, a modern gasoline engine with series engine periphery is used. In particular, the investigation of the behavior of deposits in the exhaust system of gasoline engines during cold start under dynamic driving conditions represents an extraordinary challenge due to an average lower soot concentration in the exhaust gas compared to diesel engines and so far, has not been examined in this form. A novel sampling method allows ex-situ analysis of formed deposits during a single driving cycle. Both, particle number concentration and the deposition rate are higher in the testing procedure of Real Driving Emissions (RDE) than in the inner-city part of the Worldwide harmonized Light vehicles Test Cycle (WLTC). In addition, reduced ambient temperatures increase the amount of deposits, which consist predominantly of soot and to a minor fraction of volatile compounds. Although the primary particle size distributions of the deposited soot particles do not change when boundary conditions change, the degree of graphitization within the particles increases with increasing exhaust gas temperature.

The Impact of a BI-Supported Performance Measurement System on a Public Police Force

2019 ◽  
pp. 509-527
Author(s):  
Elad Moskovitz ◽  
Adir Even
Keyword(s):  
Performance Measurement ◽  
Measurement System ◽  
Business Intelligence ◽  
Police Force ◽  
Performance Measurement System ◽  
Moderation Effect ◽  
Relative Metrics ◽  
Time Period ◽  
The Impact

Performance measurement, as an effective tool for implementing organizational strategy and assisting ongoing control and surveillance, is broadly adopted today. The performance measurement system (PMS) explored in this case study was implemented, using business intelligence (BI) technologies, for a public police force. The system lets police commanders view and analyze the performance scores of their own units and get feedback on the success of their activities. The study examines the system's impact, through analysis of the metric results over a time period of five years. The results show that the vast majority of the metrics examined indeed improved. Further, the results underscore the moderation effect of relative metrics weights, as well as the different behavior of metrics that reflect activity versus those that reflect outcomes. The study underscores both the positive and the negative aspects of those results, and discusses their implications for future PMS implementation with BI technologies.

Modelling three-way catalytic converter oriented to engine cold-start conditions

2019 ◽  
pp. 146808741985314
Author(s):  
Marcelo Real ◽  
Raffael Hedinger ◽  
Benjamín Pla ◽  
Christopher Onder
Keyword(s):  
Catalytic Converter ◽  
Cold Start
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