Study of NOx Emissions Reduction Strategy for a Naturally Aspirated 4-Cylinder Direct Injection Hydrogen ICE

2010 ◽  
Author(s):  
Kaname Naganuma ◽  
Yasuo Takagi ◽  
Atsuhiro Kawamura ◽  
Yoshio Sato
Keyword(s):  
Direct Injection ◽  
Emissions Reduction ◽  
Nox Emissions ◽  
Reduction Strategy

scholarly journals Characterization of a Novel Porous Injector for Multi-Lean Direct Injection (M-LDI) Combustor

2017 ◽  
Author(s):  
Jianing Li ◽  
Umesh Bhayaraju ◽  
San-Mou Jeng
Keyword(s):  
Air Temperature ◽  
Mass Fraction ◽  
Direct Injection ◽  
Flame Temperature ◽  
Gaseous Fuel ◽  
Nox Emissions ◽  
Fuel Injector ◽  
Porous Tube ◽  
Lean Direct Injection ◽  
Air Mixing

A generic novel injector was designed for multi-Lean Direct Injection (M-LDI) combustors. One of the drawbacks of the conventional pressure swirl and prefilming type airblast atomizers is the difficulty of obtaining a uniform symmetric spray under all operating conditions. Micro-channels are needed inside the injector for uniformly distributing the fuel. The problem of non-uniformity is magnified in smaller sized injectors. The non-uniform liquid sheet causes local fuel rich/lean zones leading to higher NOx emissions. To overcome these problems, a novel fuel injector was designed to improve the fuel delivery to the injector by using a porous stainless steel material with 30 μm porosity. The porous tube also acts as a prefilming surface. Liquid and gaseous fuels can be injected through the injector. In the present study, gaseous fuel was injected to investigate injector fuel-air mixing performance. The gaseous fuel was injected through a porous tube between two radial-radial swirling air streams to facilitate fuel-air mixing. The advantage of this injector is that it increases the contact surface area between the fuel-air at the fuel injection point. The increased contact area enhances fuel-air mixing. Fuel-air mixing and combustion studies were carried out for both gaseous and liquid fuel. Flame visualization, and emissions measurements were carried out inside the exit of the combustor. The measurements were carried out at atmospheric conditions under fuel lean conditions. Natural gas was used as a fuel in these experiments. Fuel-air mixing studies were carried out at different equivalence ratios with and without confinement. The mass fraction distributions were measured at different downstream locations from the injector exit. Flame characterization was carried out by chemiluminescence at different equivalence ratios and inlet air temperatures. Symmetry of the flame, flame length and heat release distribution were analyzed from the flame images. The effects of inlet air temperature and combustion flame temperature on emissions was studied. Emissions were corrected to 15% O2 concentration. NOx emissions increase with inlet air temperature and flame temperature. Effect of flame temperature on NOx concentration is more significant than effect of inlet air temperature. Fuel-air mixing profile was used to obtain mass fraction Probability Density Function (pdf). The pdfs were used for simulations in Chemkin Pro. The measured emissions concentrations at the exit of the injector was compared with simulations. In Chemkin model, a network model with several PSRs (perfectly stirred reactor) were utilized, followed by a mixer and a PFR (plug flow reactor). The comparison between the simulations and the experimental results was investigated.

Diesel Emissions Reduction Using a Catalyst and Water Scrubber for Underground Mine Applications

1988 ◽  
Vol 202 (4) ◽  
pp. 233-242
Author(s):  
G E Andrews ◽  
R Everest ◽  
D Jepson ◽  
S W Pang
Keyword(s):  
Diesel Engine ◽  
Direct Injection ◽  
Substantial Reduction ◽  
Diesel Emissions ◽  
Emissions Reduction ◽  
Gaseous Emissions ◽  
Engine Exhaust ◽  
Particulate Removal ◽  
Water Scrubber ◽  
Exhaust Particulate

BS 6680 requires the efficiency of coalmine diesel engine exhaust pollution-reduction devices to be determined. The efficiency of an Englehard PTX catalyst and water scubber for both particulate and gaseous emissions reduction was determined using a 533 cc single-cylinder Petter AVI direct injection diesel engine. The separate and combined influence of the two exhaust devices was determined. The water scrubber acted as aflame trap as well as an exhaust particulate trap. The catalyst gave a substantial reduction in CO and UHC gaseous emissions and particulate SOF emissions for exhaust temperatures above 250°C. However, the high MW particulate SOF, including the PAH, had a 70 per cent reduction for catalyst temperatures as low as 200°C. The water scrubber was the dominant particulate removal device, although the catalyst removal efficiency was significant for temperatures above 250° C. The scrubber also had a significant influence on the reduction in NOx emissions, with a 30 per cent removal at high exhaust temperatures.

scholarly journals Effects of Oxygenated Additives with Diesel on the Performance of D I Diesel Engine

2019 ◽  
pp. 1-9 ◽  
Author(s):  
P. Venkateswara Rao ◽  
S. Ramesh ◽  
S. Anil Kumar
Keyword(s):  
Diesel Engine ◽  
Diesel Fuel ◽  
Direct Injection ◽  
Primary Objective ◽  
Nox Emissions ◽  
Oxides Of Nitrogen ◽  
Smoke Emission ◽  
Oxygenated Additives ◽  
Blend Fuel ◽  
Fuel Formulation

The primary objective of this work is to reduce the particulate matter (PM) or smoke emission and oxides of nitrogen (NOx emissions) the two important harmful emissions and to increase the performance of diesel engine by using oxygenated additives with diesel as blend fuel. Formulation of available diesel fuel with additives is an advantage than considering of engine modification for improvement of higher output. From the available additives, three oxygenates are selected for experimentation by considering many aspects like cost, content of oxygen, flashpoint, solubility, seal etc. The selected oxygenates are Ethyl Aceto Acetate (EAA), Diethyl Carbonate (DEC), Diethylene Glycol (DEG). These oxygenates are blended with diesel fuel in proportions of 2.5%, 5% and 7.5% by volume and experiments were conducted on a single cylinder naturally aspirated direct injection diesel engine. From the results the conclusion are higher brake power and lower BSFC obtained for DEC blends at 7.5% of additive as compared to EAA, DEG and diesel at full load. In case of DEC blends the smoke emission is lower, whereas NOx emissions are very low in case of EAA additive blend fuels. The DEC can be considered is the best oxygenating additive to be blend with diesel in a proportion of 7.5% by volume.

Sector Tests of a Low NOx, Lean-Direct-Injection, Multipoint Integrated Module Combustor Concept

2002 ◽  
Author(s):  
Robert Tacina ◽  
Changlie Wey ◽  
Peter Laing ◽  
Adel Mansour
Keyword(s):  
Direct Injection ◽  
Pressure Ratio ◽  
Inlet Pressure ◽  
Inlet Temperature ◽  
Single Element ◽  
Nox Emissions ◽  
Fuel Injectors ◽  
Lean Direct Injection ◽  
Test Conditions ◽  
Engine Cycle

Results of a low-NOx combustor test with a 15° sector are presented. A multipoint, lean-direct injection concept is used. The configuration tested has 36 fuel injectors and fuel-air mixers in place of a dual annular arrangement of two conventional fuel injectors. An integrated-module approach is used for the construction where chemically etched laminates that are diffusion bonded, combine the fuel injectors, air swirlers and fuel manifold into a single element. Test conditions include inlet temperatures up to 866K, and inlet pressures up to 4825 kPa. The fuel used was Jet A. A correlation is developed relating the NOx emissions to the inlet temperature, inlet pressure, and fuel-air ratio. Using a hypothetical 55:1 pressure-ratio engine, cycle NOx emissions are estimated to be less than 40% of the 1996 ICAO standard.

US Fishing Vessel Powering and NOx Emissions

2007 ◽  
Vol 44 (03) ◽  
pp. 175-179
Author(s):  
Robert G. Latorre ◽  
Joseph P. Cardella V
Keyword(s):  
Diesel Engine ◽  
Emissions Reduction ◽  
Nox Emissions ◽  
Fishing Vessel ◽  
Fishing Fleet ◽  
The Us ◽  
Small Craft ◽  
Index Ratio

This paper presents the results of SNAME Small Craft Panel SC-3 Fishing Systems investigation of trends in US fishing vessel (Fig. 1) (L> 22.9 m) powering and NOx emissions (1900–2000). The study estimates the 1, 299 vessels in the US fishing fleet produce 306 tons/day of NOx. The largest powers are found in the decades of 1960–1980. The actual power kW is compared to a reference power kWo using the Powering Index Ratio PIR = kW/kWo. It was found that 50 to 80% of the power in seiners, trawlers, and crabber/ trapper/clam vessels have PIR > 2.5. The reduction of fishing vessel diesel engine NOx can be best achieved by adopting acceptable levels of vessel power/length for the basis of revenue and tax rather than using the vessel age as emissions reduction criteria.

scholarly journals An Investigation of the Influence of Gas Injection Rate Shape on High-Pressure Direct-Injection Natural Gas Marine Engines

Energies ◽  
2019 ◽  
Vol 12 (13) ◽  
pp. 2571 ◽  
Author(s):  
Jingrui Li ◽  
Jietuo Wang ◽  
Teng Liu ◽  
Jingjin Dong ◽  
Bo Liu ◽  
...  
Keyword(s):  
High Pressure ◽  
Natural Gas ◽  
Fuel Consumption ◽  
Direct Injection ◽  
Gas Injection ◽  
Injection Rate ◽  
Emission Characteristics ◽  
Nox Emissions ◽  
Indicated Mean Effective Pressure ◽  
Marine Engines

High-pressure direct-injection (HPDI) natural gas marine engines are widely used because of their higher thermal efficiency and lower emissions. The effects of different injection rate shapes on the combustion and emission characteristics were studied to explore the appropriate gas injection rate shapes for a low-speed HPDI natural gas marine engine. A single-cylinder model was established and the CFD model was validated against experimental data from the literature; then, the combustion and emission characteristics of five different injection rate shapes were analyzed. The results showed that the peak values of in-cylinder pressure and heat release rate profiles of the triangle shape were highest due to the highest maximum injection rate, which occurred in a phase close to the top dead center. The shorter combustion duration of the triangle shape led to higher indicated mean effective pressure (IMEP) and NOx emissions compared with other shapes. The higher initial injection rates of the rectangle and slope shapes had a negative effect on the ignition delay periods of pilot fuel, which resulted in lower in-cylinder temperature and NOx emissions. However, due to the lower in-cylinder temperature, the engine power output was also lower. Otherwise, soot, unburned hydrocarbon (UHC), and CO emissions and indicated specific fuel consumption (ISFC) increased for both rectangle and slope shapes. The trapezoid and wedge shapes achieved a good balance between fuel consumption and emissions.

NOx Emissions Reduction in an Innovative Industrial Gas Turbine Combustor (GE10 Machine): A Numerical Study of the Benefits of a New Pilot-System on Flame Structure and Emissions

2005 ◽  
Author(s):  
Antonio Andreini ◽  
Bruno Facchini ◽  
Luca Mangani ◽  
Antonio Asti ◽  
Gianni Ceccherini ◽  
...  
Keyword(s):  
Gas Turbine ◽  
Gas Turbines ◽  
Numerical Study ◽  
Flame Structure ◽  
Combustion Model ◽  
Emissions Reduction ◽  
Minimal Amount ◽  
Nox Emissions ◽  
Ambient Temperatures ◽  
Wide Range

One of the driving requirements in gas turbine design is emissions reduction. In the mature markets (especially the North America), permits to install new gas turbines are granted provided emissions meet more and more restrictive requirements, in a wide range of ambient temperatures and loads. To meet such requirements, design techniques have to take advantage also of the most recent CFD tools. As a successful example of this, this paper reports the results of a reactive 3D numerical study of a single-can combustor for the GE10 machine, recently updated by GE-Energy. This work aims to evaluate the benefits on the flame shape and on NOx emissions of a new pilot-system located on the upper part of the liner. The former GE10 combustor is equipped with fuel-injecting-holes realizing purely diffusive pilot-flames. To reduce NOx emissions from the current 25 ppmvd@15%O2 to less than 15 ppmvd@15%O2 (in the ambient temperature range from −28.9°C to +37.8°C and in the load range from 50% and 100%), the new version of the combustor is equipped with 4 swirler-burners realizing lean-premixed pilot flames; these flames in turn are stabilized by a minimal amount of lean-diffusive sub-pilot-fuel. The overall goal of this new configuration is the reduction of the fraction of fuel burnt in diffusive flames, lowering peak temperatures and therefore NOx emissions. To analyse the new flame structure and to check the emissions reduction, a reactive RANS study was performed using STAR-CD™ package. A user-defined combustion model was used, while to estimate NOx emissions a specific scheme was also developed. Three different ambient temperatures (ISO, −28.9°C and 37.8°C) were simulated. Results were then compared with experimental measurements (taken both from the engine and from the rig), resulting in reasonable agreement. Finally, an additional simulation with an advanced combustion model, based on the laminar flamelet approach, was performed. The model is based on the G-Equation scheme but was modified to study partially premixed flames. A geometric procedure to solve G-Equation was implemented as add-on in STAR-CD™.

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