Optimization of Engine Efficiency for Diesel Engine Equipped With EGR-VGT and Aftertreatment Systems

2019 ◽  
Author(s):  
Kuo Yang ◽  
Pingen Chen
Keyword(s):  
Diesel Engine ◽  
Fuel Consumption ◽  
Diesel Engines ◽  
Intrinsic Property ◽  
Nox Emission ◽  
Nox Emissions ◽  
Minimum Phase ◽  
Engine Efficiency ◽  
Simulation Results ◽  
Aftertreatment Systems

Abstract Engine efficiency improvement is very critical for medium to heavy-duty vehicles to reduce Diesel fuel consumption and enhance U.S. energy security. The tradeoff between engine efficiency and NOx emissions is an intrinsic property that prevents modern Diesel engines, which are generally equipped with exhaust gas recirculation (EGR) and variable geometry turbocharger (VGT), from achieving the optimal engine efficiency while meeting the stringent NOx emission standards. The addition of urea-based selective catalytic reduction (SCR) systems to modern Diesel engine aftertreatment systems alleviate the burden of NOx emission control on Diesel engines, which in return creates extra freedom for optimizing Diesel engine efficiency. This paper proposes two model-based approaches to locate the optimal operating point of EGR and VGT in the air-path loop to maximize the indicated efficiency of turbocharged diesel engine. Simulation results demonstrated that the engine brake specific fuel consumption (BSFC) can be reduced by up to 1.6% through optimization of EGR and VGT, compared to a baseline EGR-VGT control which considers both NOx emissions and engine efficiency on engine side. The overall equivalent BSFCs are 1.8% higher with optimized EGR and VGT control than with the baseline control. In addition, the influence of reducing EGR valve opening on the non-minimum phase behavior of the air path loop is also analyzed. Simulation results showed slightly stronger non-minimum phase behaviors when EGR is fully closed.

Engine Strategies to Meet Phase-2 Greenhouse Gas Emission Legislation for Heavy-Duty Diesel Engines

2017 ◽  
Author(s):  
Satyum Joshi ◽  
Mufaddel Dahodwala ◽  
Erik Koehler ◽  
Michael Franke
Keyword(s):  
Fuel Consumption ◽  
Nox Emission ◽  
Nox Emissions ◽  
Exhaust Gas ◽  
Phase 2 ◽  
Emission Standard ◽  
Cylinder Deactivation ◽  
Engine Efficiency ◽  
Low Nox Emission ◽  
Emission Legislation

In 2027, the fully phased-in EPA/NHTSA Phase-2 greenhouse gas (GHG) emission legislation for heavy-duty (HD) diesel engines will mandate a 5.1% reduction in fuel consumption for MY2017 tractor engines and a 4.2% reduction in fuel consumption for MY2017 vocational engines. Along with improvements in engine efficiency, manufacturers are likely to face a simultaneous challenge to achieve a significant reduction in tailpipe NOx emissions, as the ARB is expected to implement an ultra-low NOx emission standard in the 2024–27 timeframe. With this consideration, technology solutions for Phase-2 GHG will have to be NOx neutral or provide additional reduction in NOx emissions which is typically contrary to a reduction in fuel consumption. In this study, various advanced engine technologies — such as engine downsizing and downspeeding, variable compression ratio, cylinder deactivation and turbocompounding — have been evaluated to improve engine efficiency with a goal to reach Phase-2 GHG engine requirements. Simultaneously, the impact of these technologies on engine-out NOx emission and aftertreatment inlet temperature has also been evaluated. The technologies were evaluated with a GT-Power model of a 7.7 liter medium HD diesel engine applied in vocational vehicles at steady-state operating conditions as well as over transient operating profiles. Significant fuel consumption reductions were observed with engine downsizing and engine downspeeding at the same engine-out NOx emissions as the baseline engine. Cylinder deactivation showed a moderate impact on fuel consumption while variable compression ratio and turbocompounding had a much lower impact on fuel consumption. In general, exhaust gas temperatures decreased with a reduction in fuel consumption, except in the case of cylinder deactivation where significant increase in exhaust gas temperatures was observed. The results of the study show that engine efficiency improvements beyond what has been mandated by the Phase-2 GHG regulations are possible without increasing the engine-out NOx emissions of a Phase-1 GHG compliant engine. However, if an ultra-low NOx emission standard is implemented as expected, some of the efficiency gains demonstrated in this study will need to be offset to achieve higher exhaust gas temperatures and lower engine-out NOx emissions.

scholarly journals Investigation of Effect on Environmental Performance of Using LNG as Fuel for Engines in Seaport Tugboats

2021 ◽  
Vol 9 (2) ◽  
pp. 123
Author(s):  
Sergejus Lebedevas ◽  
Lukas Norkevičius ◽  
Peilin Zhou
Keyword(s):  
Diesel Engine ◽  
Natural Gas ◽  
Baltic Sea ◽  
Impact Assessment ◽  
Fuel Consumption ◽  
Dual Fuel ◽  
Nox Emissions ◽  
The Baltic Sea ◽  
Emission Analysis ◽  
The Baltic

Decarbonization of ship power plants and reduction of harmful emissions has become a priority in the technological development of maritime transport, including ships operating in seaports. Engines fueled by diesel without using secondary emission reduction technologies cannot meet MARPOL 73/78 Tier III regulations. The MEPC.203 (62) EEDI directive of the IMO also stipulates a standard for CO2 emissions. This study presents the results of research on ecological parameters when a CAT 3516C diesel engine is replaced by a dual-fuel (diesel-liquefied natural gas) powered Wartsila 9L20DF engine on an existing seaport tugboat. CO2, SO2 and NOx emission reductions were estimated using data from the actual engine load cycle, the fuel consumption of the KLASCO-3 tugboat, and engine-prototype experimental data. Emission analysis was performed to verify the efficiency of the dual-fuel engine in reducing CO2, SO2 and NOx emissions of seaport tugboats. The study found that replacing a diesel engine with a dual-fuel-powered engine led to a reduction in annual emissions of 10% for CO2, 91% for SO2, and 65% for NOx. Based on today’s fuel price market data an economic impact assessment was conducted based on the estimated annual fuel consumption of the existing KLASCO-3 seaport tugboat when a diesel-powered engine is replaced by a dual-fuel (diesel-natural gas)-powered engine. The study showed that a 33% fuel costs savings can be achieved each year. Based on the approved methodology, an ecological impact assessment was conducted for the entire fleet of tugboats operating in the Baltic Sea ports if the fuel type was changed from diesel to natural gas. The results of the assessment showed that replacing diesel fuel with natural gas achieved 78% environmental impact in terms of NOx emissions according to MARPOL 73/78 Tier III regulations. The research concludes that new-generation engines on the market powered by environmentally friendly fuels such as LNG can modernise a large number of existing seaport tugboats, significantly reducing their emissions in ECA regions such as the Baltic Sea.

Two-Stroke Marine Diesel Engine Variable Injection Timing System Performance Evaluation and Optimum Setting for Minimum Fuel Consumption at Acceptable NOx Levels

2014 ◽  
Author(s):  
Dimitrios T. Hountalas ◽  
Spiridon Raptotasios ◽  
Antonis Antonopoulos ◽  
Stavros Daniolos ◽  
Iosif Dolaptzis ◽  
...  
Keyword(s):  
Diesel Engine ◽  
Fuel Consumption ◽  
Engine Performance ◽  
Operating Conditions ◽  
Specific Fuel Consumption ◽  
Injection Timing ◽  
Nox Emissions ◽  
Pressure Measurements ◽  
Cylinder Pressure ◽  
Start Of Injection

Currently the most promising solution for marine propulsion is the two-stroke low-speed diesel engine. Start of Injection (SOI) is of significant importance for these engines due to its effect on firing pressure and specific fuel consumption. Therefore these engines are usually equipped with Variable Injection Timing (VIT) systems for variation of SOI with load. Proper operation of these systems is essential for both safe engine operation and performance since they are also used to control peak firing pressure. However, it is rather difficult to evaluate the operation of VIT system and determine the required rack settings for a specific SOI angle without using experimental techniques, which are extremely expensive and time consuming. For this reason in the present work it is examined the use of on-board monitoring and diagnosis techniques to overcome this difficulty. The application is conducted on a commercial vessel equipped with a two-stroke engine from which cylinder pressure measurements were acquired. From the processing of measurements acquired at various operating conditions it is determined the relation between VIT rack position and start of injection angle. This is used to evaluate the VIT system condition and determine the required settings to achieve the desired SOI angle. After VIT system tuning, new measurements were acquired from the processing of which results were derived for various operating parameters, i.e. brake power, specific fuel consumption, heat release rate, start of combustion etc. From the comparative evaluation of results before and after VIT adjustment it is revealed an improvement of specific fuel consumption while firing pressure remains within limits. It is thus revealed that the proposed method has the potential to overcome the disadvantages of purely experimental trial and error methods and that its use can result to fuel saving with minimum effort and time. To evaluate the corresponding effect on NOx emissions, as required by Marpol Annex-VI regulation a theoretical investigation is conducted using a multi-zone combustion model. Shop-test and NOx-file data are used to evaluate its ability to predict engine performance and NOx emissions before conducting the investigation. Moreover, the results derived from the on-board cylinder pressure measurements, after VIT system tuning, are used to evaluate the model’s ability to predict the effect of SOI variation on engine performance. Then the simulation model is applied to estimate the impact of SOI advance on NOx emissions. As revealed NOx emissions remain within limits despite the SOI variation (increase).

Experimental Study on the Combustion Process and Performance of Diesel Engines Fueled by Emulsion Diesel With Novel Organic Additives

2013 ◽  
Author(s):  
Wenming Yang ◽  
Hui An ◽  
Jing Li ◽  
Amin Maghbouli ◽  
Kian Jon Chua
Keyword(s):  
Diesel Engine ◽  
Diesel Engines ◽  
Thermal Efficiency ◽  
Gasoline Engine ◽  
Combustion Process ◽  
Nox Emissions ◽  
Organic Additives ◽  
Oil Droplets ◽  
And Performance ◽  
One Year

Transportation is one of the major contributors to the world’s energy consumption and greenhouse gases emissions. The need for increased efficiency has placed diesel engine in the spotlight due to its superior thermal efficiency and fuel economy over gasoline engine. However, diesel engines also face the major disadvantage of increased NOx emissions. To address this issue, three types of emulsion fuels with different water concentrations (5%, 10% and 15% mass water) are produced and tested. Novel organic materials (glycerin and ployethoxy-ester) are added in the fuel to provide extra oxygen for improving combustion. NP-15 is added as surfactant which can help to reduce the oil and water surface tension, activates their surface, and maximizes their superficial contact areas, thereby forming a continuous and finely dispersed droplets phase. The stability of the emulsion fuels is tested under various environmental temperature for one year, and no significant separation is observed. It is better than normal emulsion fuel which can only maintain the state for up to three months. The combustion process and performance of the emulsion fuels are tested in a four-stroke, four cylinder diesel engine. The results indicate that the water droplets enclosed in the emulsion fuel explode at high temperature environment and help to break up the big oil droplets into smaller ones, thereby significantly increase the surface area of the oil droplets and enhance the heat transfer from hot gas to the fuel. As a result, the fuel evaporation is improved and the combustion process is accelerated, leading to an improved brake thermal efficiency (up to 14.2%). Meanwhile, the presence of the water causes the peak temperature of the flame to drop, thereby significantly bringing down the NOx emissions by more than 30%.

scholarly journals Development of a control-oriented model to optimise fuel consumption and NOX emissions in a DI Diesel engine

2014 ◽  
Vol 119 ◽  
pp. 405-416 ◽  
Author(s):  
S. Molina ◽  
C. Guardiola ◽  
J. Martín ◽  
D. García-Sarmiento
Keyword(s):  
Diesel Engine ◽  
Fuel Consumption ◽  
Nox Emissions ◽  
Di Diesel Engine ◽  
Optimise Fuel Consumption

scholarly journals INFLUENCE OF THE BIODIESEL FUELS WITH MULTIFUNCTIONAL ADDITIVES ON THE DIESEL ENGINE EFFICIENCY

2015 ◽  
Author(s):  
Renaldas BARANAUSKAS ◽  
Risto ILVES ◽  
Arne KÜÜT ◽  
Jüri OLT
Keyword(s):  
Diesel Engine ◽  
Fuel Consumption ◽  
Engine Speed ◽  
Repeated Loading ◽  
Exhaust Gas ◽  
Maximum Torque ◽  
Engine Efficiency ◽  
Multifunctional Additives ◽  
Biodiesel Fuels

The article presents the tests of the engine Valmet 320 DS installed in the teststand "Schenck Dynas3 LI 250". For these tests biodiesel produced by JSC Rapsoila was used. The test was carried out causing the engine speed to 2600 rpm and loading gradually to maximum. Torque (Te), engine speed (ne), fuel consumption (Bf), the pressure in the cylinder (Pe) and exhaust gas CO, CO2, O2, HC, NOx were measured. Initially, measurements were carried out using biodiesel (RME). After that, biodiesel was added with the additive Valvoline VPS HD Diesel System Complete keeping a ratio of 100:1. In order to evaluate the effects of additives the engine was working two hours using biodiesel and additive mixture. After two hours the measurements were repeated loading the engine in the same mode. The work presents the results of tests carried out.

scholarly journals EFEK LOKASI INJEKTOR TERHADAP INDEKS PENCAMPURAN AMMONIA UNTUK SCR DENGAN MIXER DINAMIK

ROTASI ◽  
2014 ◽  
Vol 16 (4) ◽  
pp. 48
Author(s):  
Syaiful Syaiful ◽  
Iseu Andriani
Keyword(s):  
Diesel Engine ◽  
Diesel Engines ◽  
High Efficiency ◽  
Gasoline Engine ◽  
Catalytic Reduction ◽  
Threshold Level ◽  
Nox Emissions ◽  
Mixing Index ◽  
Engine Exhaust ◽  
Gasoline Engines

Diesel engines many are used as transportation mode in the land and sea compared with gasoline engines due to their high efficiency and durability. However, diesel engine releases much more NOx and soot emissions than that of gasoline engine. NOx is formed from a reaction of Nitrogen and Oxygen at high temperature. If these emissions are breathed into human body resulting respiratory disorders such as emphysema and bronchitis as well as lungs tissue damage. Therefore, NOx emissions controll is required to reduce them reaching under a threshold level. An effective method for controlling NOx emissions produced by the diesel engines is by injecting ammonia obtained from urea into selective catalytic reduction (SCR method) system. Ammonia by means of catalyst reacts with NOx forming Nitrogen (N2) and Water (H2O). Therefore, a chance of each ammonia particle to react with each NOx particle is required to consider. A reaction quality between ammmonia and NOx particles can be increased by improving a mixing index. One of the methods to increase the mixing index is by using a dynamic mixer.There are several factors which influence the increase of mixing index. One of these factors is a location of ammonia injector. Since this work is focused on investigating the effect of ammonia injector location on the mixing index of ammonia to diesel engine exhaust gases which content of NOx emissions

Sign in / Sign up

Export Citation Format

Share Document