Cold Start Calibration of Current PZEV Vehicles and the Impact of LEV-III Emission Regulations

2012 ◽  
Author(s):  
Douglas Ball ◽  
David Moser
Keyword(s):  
Cold Start ◽  
Emission Regulations ◽  
The Impact

EGR cylinder deactivation strategy to accelerate the warm-up and restart processes in a Diesel engine operating at cold conditions

2021 ◽  
pp. 146808742110395
Author(s):  
José Galindo ◽  
Vicente Dolz ◽  
Javier Monsalve-Serrano ◽  
Miguel Angel Bernal Maldonado ◽  
Laurent Odillard
Keyword(s):  
Steady State ◽  
Diesel Engine ◽  
Internal Combustion Engines ◽  
Cold Start ◽  
Pollutant Emissions ◽  
Oxidation Catalyst ◽  
Maximum Efficiency ◽  
Warm Up ◽  
Cylinder Deactivation ◽  
The Impact

The aftertreatment systems used in internal combustion engines need high temperatures for reaching its maximum efficiency. By this reason, during the engine cold start period or engine restart operation, excessive pollutant emissions levels are emitted to the atmosphere. This paper evaluates the impact of using a new cylinder deactivation strategy on a Euro 6 turbocharged diesel engine running under cold conditions (−7°C) with the aim of improving the engine warm-up process. This strategy is evaluated in two parts. First, an experimental study is performed at 20°C to analyze the effect of the cylinder deactivation strategy at steady-state and during an engine cold start at 1500 rpm and constant load. In particular, the pumping losses, pollutant emissions levels and engine thermal efficiency are analyzed. In the second part, the engine behavior is analyzed at steady-state and transient conditions under very low ambient temperatures (−7°C). In these conditions, the results show an increase of the exhaust temperatures of around 100°C, which allows to reduce the diesel oxidation catalyst light-off by 250 s besides of reducing the engine warm-up process in approximately 120 s. This allows to reduce the CO and HC emissions by 70% and 50%, respectively, at the end of the test.

scholarly journals Measuring On-Road Vehicle Emissions with Multiple Instruments Including Remote Sensing

Atmosphere ◽  
2019 ◽  
Vol 10 (9) ◽  
pp. 516 ◽  
Author(s):  
Robin Smit ◽  
Phil Kingston
Keyword(s):  
Remote Sensing ◽  
Air Quality ◽  
Capture Rate ◽  
Quality Criteria ◽  
Cold Start ◽  
Operating Conditions ◽  
Accurate Information ◽  
Diesel Vehicles ◽  
Additional Equipment ◽  
The Impact

The objective of this paper is to use remote sensing to measure on-road emissions and to examine the impact and usefulness of additional measurement devices at three sites. Supplementing remote sensing device (RSD) equipment with additional equipment increased the capture rate by almost 10%. Post-processing of raw data is essential to obtain useful and accurate information. A method is presented to identify vehicles with excessive emission levels (high emitters). First, an anomaly detection method is applied, followed by identification of cold start operating conditions using infrared vehicle profiles. Using this method, 0.6% of the vehicles in the full (enhanced) RSD data were identified as high emitters, of which 35% are likely in cold start mode where emissions typically stabilize to low hot running emission levels within a few minutes. Analysis of NOx RSD data confirms that poor real-world NOx performance of Euro 4/5 light-duty diesel vehicles observed around the world is also evident in Australian measurements. This research suggests that the continued dieselisation in Australia, in particular under the current Euro 5 emission standards and the more stringent NO2 air quality criteria expected in 2020 and 2025, could potentially result in local air quality issues near busy roads.

scholarly journals Testing and evaluation of cold-start emissions from a gasoline engine in RDE test at two different ambient temperatures

2021 ◽  
Vol 11 (1) ◽  
pp. 425-434
Author(s):  
Jacek Pielecha ◽  
Kinga Skobiej ◽  
Karolina Kurtyka
Keyword(s):  
Ambient Temperature ◽  
Gasoline Engine ◽  
Cold Start ◽  
Exhaust Emissions ◽  
Operating Parameters ◽  
Time Interval ◽  
Vehicle Speed ◽  
Passenger Cars ◽  
Ambient Temperatures ◽  
The Impact

Abstract In order to better reflect the actual ecological performance of vehicles in traffic conditions, both the emission standards and the applied emission tests are being developed, for example by considering exhaust emissions for a cold engine start. This article presents the research results on the impact of ambient temperature during the cold start of a gasoline engine in road emission tests. The Real Driving Emissions (RDE) tests apply to passenger cars that meet the Euro 6 emissions norm and they are complementary to their type approval tests. A portable emissions measurement system was used to record the engine and vehicle operating parameters, as well as to measure the exhaust emissions during tests. This allowed for parameters such as engine load, engine speed and vehicle speed to be monitored. The cold start conditions for two different temperatures (8°C and 25°C) were compared in detail. Moreover, the engine operating parameters, exhaust concentration values and road emissions for the 300 s time interval, were compared. The summary of the article presents the share of a passenger car’s cold start phase for each exhaust compound in the urban part of the test and in the entire Real Driving Emissions test depending on the ambient temperature.

Dynamics of spray impingement wall film under cold start conditions

2019 ◽  
Vol 21 (2) ◽  
pp. 319-329 ◽  
Author(s):  
Xuesong Li ◽  
Di Xiao ◽  
Scott E Parrish ◽  
Ronald O Grover ◽  
David LS Hung ◽  
...  
Keyword(s):  
Internal Combustion Engines ◽  
Laser Diagnostics ◽  
Numerical Models ◽  
Cold Start ◽  
Mie Scattering ◽  
Optical Measurements ◽  
Fuel Film ◽  
Wall Film ◽  
Spray Impingement ◽  
The Impact

Fuel film that adhered on engine walls from spray impingement is considered a primary source of harmful combustion emissions. However, the physics of the wall film formation, propagation, and breakup is not fully understood yet because of its multiphase nature. Existing literature has revealed that the mass transportation within the fuel film takes a wave propagation form. This article aims to identify the dynamics of the wall film during spray impingement via high-speed laser diagnostics. In this work, a single-hole injector was used and the spray impinged onto a stage made of sapphire glass for diagnostics purposes. Iso-octane was used as the fuel and 10% ethanol was blended to dope rhodamine 6G as the fluorescent species for laser excitation. Simultaneous optical measurements, such as laser-induced fluorescence and Mie scattering, are performed to obtain the characteristics of the wall film quantitatively. Various aspects of the wall film, including the frequency of the wave, wave speed, and wave height, are inspected. The impact of fuel temperature and wall temperature under typical cold-start conditions are also studied to investigate the temperature dependence of the wall film dynamics. The research is also intended to provide quantitative experimental data for numerical models for impingement prediction and thus help the process of emission reduction and combustion optimization of internal combustion engines.

scholarly journals Engine Performance and Emissions Analysis in a Cold, Intermediate and Hot Start Diesel Engine

2020 ◽  
Vol 10 (11) ◽  
pp. 3839 ◽  
Author(s):  
Faisal Lodi ◽  
Ali Zare ◽  
Priyanka Arora ◽  
Svetlana Stevanovic ◽  
Mohammad Jafari ◽  
...  
Keyword(s):  
Diesel Engine ◽  
Cold Start ◽  
Lubricating Oil ◽  
Coolant Temperature ◽  
Effective Pressure ◽  
Warm Up ◽  
Hot Start ◽  
Depth Analysis ◽  
Performance And Emissions ◽  
The Impact

Presented in this paper is an in-depth analysis of the impact of engine start during various stages of engine warm up (cold, intermediate, and hot start stages) on the performance and emissions of a heavy-duty diesel engine. The experiments were performed at constant engine speeds of 1500 and 2000 rpm on a custom designed drive cycle. The intermediate start stage was found to be longer than the cold start stage. The oil warm up lagged the coolant warm up by approximately 10 °C. During the cold start stage, as the coolant temperature increased from ~25 to 60 °C, the brake specific fuel consumption (BSFC) decreased by approximately 2% to 10%. In the intermediate start stage, as the coolant temperature reached 70 °C and the injection retarded, the indicated mean effective pressure (IMEP) and the brake mean effective pressure (BMEP) decreased by approximately 2% to 3%, while the friction mean effective pressure (FMEP) decreased by approximately 60%. In this stage, the NOx emissions decreased by approximately 25% to 45%, while the HC emissions increased by approximately 12% to 18%. The normalised FMEP showed that higher energy losses at lower loads were most likely contributing to the heating of the lubricating oil.

Study on Cold Start Influence Factors of Three Way Catalytic Converter

2013 ◽  
Vol 385-386 ◽  
pp. 172-175
Author(s):  
Hao Cai ◽  
Li Ping Yu ◽  
Jin Ke Gong ◽  
Yu He Geng ◽  
Ya Fei Liu
Keyword(s):  
Numerical Simulation ◽  
Ambient Temperature ◽  
Gas Phase ◽  
Catalytic Converter ◽  
Influence Factors ◽  
Cold Start ◽  
Gas Phase Reactions ◽  
Reactor Model ◽  
Exhaust Temperature ◽  
The Impact

This article has established a three-way catalytic converter reactor model of gas phase reactions and surface reactions. Based on this model, cold start transient emission numerical simulation has been done. The result shows that the influence of ambient temperature and exhaust temperature on the HC is much greater than the impact on the CO.

Multilevel term analysis for adaptive document filtering1

2020 ◽  
Vol 24 ◽  
pp. 3-14
Author(s):  
Adrian Fonseca Bruzón ◽  
Aurelio López-López ◽  
José E. Medina Pagola
Keyword(s):  
Information Needs ◽  
User Profile ◽  
Cold Start ◽  
Semantic Content ◽  
Textual Structure ◽  
Document Filtering ◽  
The Impact ◽  
Term Analysis ◽  
Cold Start Problem

Humans tend to organize information in documents in a logical and intentional way. This organization, which we call textual structure, is commonly in terms of sections, chapters, paragraphs, or sentences. This structure facilitates the understanding of the content that we want to transmit to the readers. However, such structure, in which we usually encode the semantic content of information, is not usually exploited by the filtering methods for the construction of a user profile. In this work, we propose the use of term relations considering different context levels for enhancing document filtering. We propose methods for obtaining the representation, considering the existence of imbalance between the documents that satisfy the information needs of users, as well as the Cold Start problem (having scarce information) during the initial construction of the user profile. The experiments carried out allowed to assess the impact, in terms of T11SU measure, on the filtering task of the proposed representation.

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