Multi-Dimensional Engine Modeling Study of EGR, Fuel Pressure, Post-Injection and Compression Ratio for a Light Duty Diesel Engine

2014 ◽  
Author(s):  
Fabio L. Almeida ◽  
Philip Zoldak ◽  
Yan Wang ◽  
Andrzej Sobiesiak ◽  
Pedro T. Lacava
Keyword(s):  
Diesel Engine ◽  
Fuel Economy ◽  
Computational Study ◽  
Air Entrainment ◽  
Droplet Breakup ◽  
Particulate Filter ◽  
Post Injection ◽  
Lifted Flame ◽  
Light Duty ◽  
Soot Emissions

For copious levels of exhaust gas recirculation (EGR) (>30 %), oxides of nitrogen (NOx) emissions can be reduced from Euro V to Euro VI regulated levels at the expense of fuel economy and soot emissions. The Lifted-Flame Concept (LFC) has been demonstrated by several researchers to be successful in reducing NOx, while minimizing soot emissions and impact to fuel economy. By simultaneously applying increased EGR and fuel pressure the LFC extends the lift-off length of a diffusion flame and enhances fuel-air entrainment leading to improved fuel and oxygen utilization. When combined with advanced turbocharging and EGR systems the LFC applied to a modern light duty (LD) diesel engine can result in improved fuel economy and lower soot emissions and shows good potential for meeting low soot engine-out targets. In the proposed paper a computational study was conducted using a multi-dimensional engine model. A modified 3D CFD KIVA code with detailed chemistry solver was used to model the diesel fuel spray, droplet breakup, vaporization, mixing, auto-ignition and subsequent heat release and emissions. The model uses inputs from 1D Amesim electro-hydraulic solver to generate the rate of injection (ROI) profile to raise pressure of 1800 bar to 2500 bar as well as to include a simulated post-injection. A 1D model using GT-Power was developed and utilized to provide air system boundary conditions for the 3D CFD model. Post-processing optimization was conducted using Matlab to identify minimum fuel economy and soot emissions for the study of several parameters. The objective of the study was to demonstrate Euro VI emissions levels on a 3.2 L LD diesel engine without NOx aftertreatment and minimal impact to fuel economy using the lifted flame concept. The engine-out NOx emission level was targeted at 0.4 g/kWh and the soot levels were targeted at 0.2 g/kWh assuming diesel particulate filter would be used for after-treatment. The results of the computational study successfully demonstrate the potential of the lifted flame concept to meet Euro VI without the use of NOx aftertreatment technology.

Effects of B20 on Emissions and the Performance of a Diesel Particulate Filter in a Light-Duty Diesel Engine

2009 ◽  
Author(s):  
Amy M. Peterson ◽  
Po-I Lee ◽  
Ming-Chia Lai ◽  
Ming-Cheng Wu ◽  
Craig L. DiMaggio ◽  
...  
Keyword(s):  
Diesel Engine ◽  
Diesel Particulate Filter ◽  
Oxidation Catalyst ◽  
Engine Oil ◽  
Particulate Filter ◽  
Oil Viscosity ◽  
Regeneration Rate ◽  
Diesel Particulate ◽  
Light Duty ◽  
Active Regeneration

This paper compares 20% bio-diesel (B20-choice white grease) fuel with baseline ultra low sulfur diesel (ULSD) fuel on the emissions and performance of a diesel oxidation catalyst (DOC) and diesel particulate filter (DPF) coupled to a light-duty 4-cylinder 2.8-liter common-rail DI diesel engine. The present paper focuses on the comparison of the fuel effects on loading and active regeneration of the DPF between B20 and ULSD. B20, in general, produces less soot and has lower regeneration temperature compared to soot loaded with ULSD. NO2 concentrations before the DPF were found to be 6% higher with B20, indicating more availability of NO2 to oxidize the soot. Exhaust speciation of the NO2 availability indicates that the slight increase in NOx from B20 is not the dominant cause for the lower temperature regeneration and faster regeneration rate but the reactivity of the soot that is in the DPF. Formaldehyde concentrations are found to be higher with B20 during regeneration due to increased oxygen concentrations in the exhaust stream. Finally the oil dilution effect due to post injection to actively regenerate the DPF is also investigated using a prototype oil sensor and FTIR instrumentation. Utilizing an active regeneration strategy accentuates the possibility of fuel oil dilution of the engine oil. The onboard viscosity oil sensor used was in good agreement with the viscosity bench test and FTIR analysis and provided oil viscosity measurement over the course of the project. Operation with B20 shows significant fuel dilution and needs to be monitored to prevent engine deterioration.

scholarly journals Swirl ratio and post injection strategies to improve late cycle diffusion combustion in a light-duty diesel engine

2017 ◽  
Vol 123 ◽  
pp. 365-376 ◽  
Author(s):  
Jesús Benajes ◽  
Jaime Martín ◽  
Antonio García ◽  
David Villalta ◽  
Alok Warey
Keyword(s):  
Diesel Engine ◽  
Diffusion Combustion ◽  
Post Injection ◽  
Swirl Ratio ◽  
Light Duty ◽  
Injection Strategies

Development of a Euro VI Diesel Engine System Optimised to Deliver Fuel Economy and Emissions Improvements on a Series Hybrid City Bus Application for One of the World’s Busiest Bus Networks

2014 ◽  
Author(s):  
Jeevan Ghadge ◽  
Alok Krishnan ◽  
Samarth Gupta ◽  
Dhilip Balasundaram ◽  
Tim Best
Keyword(s):  
Diesel Engine ◽  
Hybrid System ◽  
Fuel Economy ◽  
Real World ◽  
Engine Speed ◽  
System Level ◽  
Particulate Filter ◽  
Tail Pipe ◽  
Hybrid Bus ◽  
Engine System

Ongoing efforts to reduce CO2 and other pollutant tail pipe emissions have led to escalated demand for diesel-electric hybrid bus powertrains in Europe, similar to the trend in passenger car markets. This is fuelled by public expectations and initiatives by various European governments to reward bus fleet operators for reduced in-city emissions and noise thus improving air quality and wellbeing of the general population. This paper describes the engineering efforts that developed a Euro VI certified diesel engine system, catering for series hybrids operating under ‘charge-depleting’ as well as ‘load following’ battery management strategies. The development team delivered improved fuel economy whilst dealing with requirements around legislation, unique customer duty cycles and engine mechanical robustness. Focus was placed on capturing requirements from a diverse range of sources and harmonising them to develop a technical solution fit for purpose in day to day operation that differs from validation cycles and standard drivetrain operation. In order to deliver a field-ready solution, application specific tuning and validation processes had to be defined and developed. This was achieved through close coordination with the European bus OEMs and their chosen hybrid system suppliers. Six-sigma tools were used to highlight key expectations and drive technical solutions. At a system level the focus was on OBD reliability, exhaust after-treatment management, controls functionality, hardware durability and tail pipe emissions. Performance targets including the number of start-stops per hour, idle management and engine speed-torque ramp rates were defined. Drive cycle simulations helped define optimal engine and hybrid system operating strategies followed by physical testing to further optimise these running points. Vehicle-level validation was completed through field testing, specific European bus test cycles, as well as under exceptional scenarios encountered in real world use. This exercise was designed to find and solve interface and OBD issues. Integration challenges in the areas of engine speed-torque control, diesel particulate filter management and HVAC control were addressed. The outcome is the release of a bespoke Euro VI diesel engine package, which enabled the hybrid bus system to exceed customer expectations. This integrated system operates on a set of optimised parameters delivering efficient sub system behaviour including aftertreatment management, engine protection and operating state control. It handles the full range of real-world vehicle operation with improved fuel economy, frequent start/stop operation and enhanced driveability.

Effects of B20 on Emissions and the Performance of a Diesel Particulate Filter in a Light-Duty Diesel Engine

2010 ◽  
Vol 132 (11) ◽  
Author(s):  
Amy M. Peterson ◽  
Po-I Lee ◽  
Ming-Chia Lai ◽  
Ming-Cheng Wu ◽  
Craig L. DiMaggio ◽  
...  
Keyword(s):  
Diesel Engine ◽  
Diesel Particulate Filter ◽  
Oxidation Catalyst ◽  
Engine Oil ◽  
Particulate Filter ◽  
Oil Viscosity ◽  
Regeneration Rate ◽  
Diesel Particulate ◽  
Light Duty ◽  
Active Regeneration

This paper compares 20% biodiesel (B20-choice white grease) fuel with baseline ultra low sulfur diesel (ULSD) fuel on the emissions and performance of a diesel oxidation catalyst (DOC) and diesel particulate filter (DPF) coupled to a light duty four-cylinder 2.8-l common-rail DI diesel engine. The present paper focuses on the comparison of the fuel effects on loading and active regeneration of the DPF between B20 and ULSD. B20, in general, produces less soot and has lower regeneration temperature, compared with soot loaded with ULSD. NO2 concentrations before the DPF were found to be 6% higher with B20, indicating more availability of NO2 to oxidize the soot. Exhaust speciation of the NO2 availability indicates that the slight increase in NOx from B20 is not the dominant cause for the lower temperature regeneration and faster regeneration rate, but the reactivity of the soot that is in the DPF. Formaldehyde concentrations are found to be higher with B20 during regeneration, due to increased oxygen concentrations in the exhaust stream. Finally, the oil dilution effect due to post injection to actively regenerate the DPF is also investigated using a prototype oil sensor and Fourier transform infrared (FTIR) instrumentation. Utilizing an active regeneration strategy accentuates the possibility of fuel oil dilution of the engine oil. The onboard viscosity oil sensor used was in good agreement with the viscosity bench test and FTIR analysis, and provided oil viscosity measurement over the course of the project. The operation with B20 shows significant fuel dilution and needs to be monitored to prevent engine deterioration.

Sign in / Sign up

Export Citation Format

Share Document