A Study on Reducing the NOx Emission of the L21/31 Medium-Speed Marine Diesel Engine for IMO Tier Emission Legislation

2013 ◽  
Vol 291-294 ◽  
pp. 1920-1924
Author(s):  
Min Xiao ◽  
Hui Chen
Keyword(s):  
Numerical Simulation ◽  
Diesel Engine ◽  
Fuel Injection ◽  
Nox Emission ◽  
Injection Timing ◽  
Marine Diesel Engine ◽  
Nox Emissions ◽  
Variable Parameters ◽  
Medium Speed ◽  
Marine Diesel

The KIVA-3V program was used to make numerical simulation for L21/31 type of medium-speed marine diesel engine about the NOx emissions and the affection of NOx changing process on different variable parameters under the Tier Ⅱstandard. On this basis, a discussion towards the NOx emission of the model fueling with dimethyl ether (DME) to meet the Tier Ⅲ standard is offered. The results show that reducing the intake temperature, load and speed, postponing the fuel injection timing and intake lag angle properly can decrease the NOx emissions within the limits of NOx in TierⅡ standard. Comparing the results of the numerical simulation of DME and diesel fuel, the NOx emission of the former one is 60.85% of the latter one, and the NOx emission of changing variable parameters on DME engine is 35.56% of the original type of diesel engine, very close to the Tier Ⅲ.

Study on Reducing NOx Emission from a Marine Diesel Engine

2013 ◽  
Vol 850-851 ◽  
pp. 1313-1319
Author(s):  
Song Zhou ◽  
Yan Liu ◽  
Cai Ling Li
Keyword(s):  
Diesel Engine ◽  
Fuel Injection ◽  
Nox Emission ◽  
Injection Timing ◽  
Marine Diesel Engine ◽  
Engine Test ◽  
Improved Method ◽  
Fuel Injection Timing ◽  
Marine Diesel ◽  
Simulation Results

This paper aimed on the effects of several technologies on engine NOx emission via simulation, an improved method to reduce engine NOx emission was obtained according the simulation results and was verified by engine test. The study uncovered that a retarded fuel injection timing would reduce engine NOx emission and make it below IMO limitation, while the penalty of fuel consumption is under tolerance of engine operator. The method adopted in this research can bring engine NOx emission under current IMO requirement, and this has been verified by engine test.

Comparison of Alternative EGR Systems for a Medium Speed Diesel Engine

2014 ◽  
Author(s):  
Sebastian Freund ◽  
Thomas M. Lavertu ◽  
Robert Mischler ◽  
Roy J. Primus
Keyword(s):  
Diesel Engine ◽  
Fuel Injection ◽  
High Rate ◽  
Intake Manifold ◽  
Injection Timing ◽  
Nox Emissions ◽  
Exhaust Gas ◽  
Power Requirement ◽  
Medium Speed ◽  
Compressor Power

Meeting future regulations for diesel engine NOx emissions with in-cylinder solutions will require a high rate of exhaust gas recirculation (EGR). For medium speed diesel engines, the exhaust manifold pressure is typically lower than that of the intake manifold, necessitating a rise in the exhaust gas pressure for exhaust flow to be introduced into the intake manifold. In this study, four high-pressure EGR engine concepts are investigated as a means to meet EPA Tier 4 NOx emissions. These concepts include a system with an EGR pump, one with a power turbine downstream of the turbocharger (i.e., turbocompounding), one with dedicated donor EGR cylinders and the use of a backpressure valve. For each system, an optimum set of parameters that included intake valve timing, intake manifold pressure, and fuel injection timing were found that satisfy the emissions requirements while staying within the mechanical limits of the system. From an efficiency perspective, the turbocompound system is generally superior, followed by the donor cylinder concept. The EGR pumping system typically has lower overall efficiency due to the compressor power requirement and the use of a backpressure valve, representing the baseline for comparison, produced the lowest system efficiency.

scholarly journals Combustion and Emissions Investigation on Low-Speed Two-Stroke Marine Diesel Engine with Low Sulfur Diesel Fuel

2019 ◽  
Vol 26 (1) ◽  
pp. 153-161 ◽  
Author(s):  
Zhiyuan Yang ◽  
Qinming Tan ◽  
Peng Geng
Keyword(s):  
Diesel Engine ◽  
Fuel Consumption ◽  
Working Conditions ◽  
Diesel Fuel ◽  
Fuel Injection ◽  
Nox Emission ◽  
Marine Diesel Engine ◽  
Marine Diesel ◽  
Test Engine ◽  
Low Sulfur

Abstract With the implementation and expansion of international sulfur emission control areas, effectively promoted the marine low sulfur diesel fuel (MLSDF) used in marine diesel engines. In this study, a large low-speed, two-stroke, cross-head, common rail, electronic fuel injection marine diesel engine (B&W 6S35ME-B9) was used for the study. According to diesel engine’s propulsion characteristics, experiments were launched respectively at 25%, 50%, 75%, 100% load working conditions with marine low sulfur diesel fuel to analyze the fuel consumption, combustion characteristics and emissions (NOx, CO2, CO, HC) characteristics. The results showed that: Marine diesel engine usually took fuel injection after top dead center to ensure their safety control NOx emission. From 25% to 75% load working condition, engine’s combustion timing gradually moved forward and the inflection points of pressure curve after top dead center also followed forward. While it is necessary to control pressure and reduce NOx emission by delaying fuel injection timing at 100% load. Engine’s in-cylinder pressure, temperature, and cumulative heat release were increased with load increasing. Engine’s CO2 and HC emissions were significantly reduced from 25% to 75% load, while they were increased slightly at 100% load. Moreover, the fuel consumption rate had a similar variation and the lowest was only 178 g/kW·h at 75% load of the test engine with MLSDF. HC or CO emissions at four tests’ working conditions were below 1.23 g/kW·h and the maximum difference was 0.2 or 0.4 g/kW·h respectively, which meant that combustion efficiency of the test engine with MLSDF is good. Although the proportion of NOx in exhaust gas increased with engine’s load increasing, but NOx emissions were always between 12.5 and 13.0 g/kW·h, which was less than 14.4 g/kW·h. Thus, the test engine had good emissions performance with MLSDF, which could meet current emission requirements of the International Maritime Organization.

scholarly journals The influence of fuel injection pump malfunctions of a marine 4-stroke Diesel engine on composition of exhaust gases

2016 ◽  
Vol 167 (4) ◽  
pp. 53-57
Author(s):  
Joanna LEWIŃSKA
Keyword(s):  
Diesel Engine ◽  
Fuel Consumption ◽  
Thermodynamic Parameters ◽  
Laboratory Study ◽  
Fuel Injection ◽  
Marine Diesel Engine ◽  
Fuel Pump ◽  
Engine Cylinder ◽  
Marine Diesel ◽  
Fuel Leakage

The article presents results of a laboratory study on exhaust gas emission level from a marine diesel engine. The object of the laboratory study was a four-stroke marine diesel engine type Al 25/30 Sulzer, operated at a constant speed. The examination on the engine was carried out according to regulations of the Annex VI to MARPOL 73/78 Convention. The laboratory study consisted of 3 observations: the engine assumed to be operating without malfunctions, delay of the fuel injection by 5° of crankshaft angle in the second engine cylinder, and the leakage of the fuel pump on the second engine cylinder. Additionally, parameters of fuel consumption and thermodynamic parameters of the marine engine were measured during the research. Simulated malfunctions caused changes in total weighed NOx, CO, and CO2 emissions for all considered engine loads. All simulated malfunctions caused a small change in measured thermodynamic parameters of the engine. The engine operation with the delayed fuel injection and the fuel leakage in the fuel pump in one cylinder caused a decrease of NOx and CO emission level. Fuel leakage in the fuel pump causes the CO2 emission to decrease only at low engine load. Calculations of the weighed specific fuel consumption present a 1-2% change in the engine efficiency.

Discrete Speed Controller Design of a Marine Diesel Engine Including Sampling Effects due to Fuel Injection

2002 ◽  
Vol 8 (5) ◽  
pp. 659-671 ◽  
Author(s):  
Mosaad Mosleh ◽  
Amier Al-Ali
Keyword(s):  
Diesel Engine ◽  
Fuel Injection ◽  
Controller Design ◽  
Linear Time ◽  
Marine Diesel Engine ◽  
Linear Time Invariant ◽  
Speed Controller ◽  
Injection Process ◽  
Loop Transfer Function ◽  
Marine Diesel

A linear time invariant (LTI) model of a marine diesel engine is presented. The effect of the discontinuity of the fuel injection into the cylinders and the injection period is considered. The proposed discrete model consists of a sampler and zero-order-hold mechanism, representing the fuel injection process. The design of the discrete controller is based on the pole assignment of the characteristic polynomial of the closed-loop transfer function with the goal of achieving zero steady-state error, and satisfying other design specifications. A numerical example illustrating the characteristic performance of a two stroke marine diesel engine is presented.

Progress on the Investigation of Coal-Water Slurry Fuel Combustion in a Medium-Speed Diesel Engine: Part 5—Combustion Studies

1992 ◽  
Vol 114 (3) ◽  
pp. 515-521 ◽  
Author(s):  
B. D. Hsu ◽  
G. L. Confer ◽  
Z. J. Shen
Keyword(s):  
Diesel Engine ◽  
Fuel Injection ◽  
Injection Pressure ◽  
Combustion Efficiency ◽  
Fuel Combustion ◽  
Injection Timing ◽  
Water Slurry ◽  
Medium Speed ◽  
Engine Part ◽  
Coal Water Slurry

In the GE 7FDL single-cylinder research diesel engine, coal-water slurry (CWS) fuel combustion optimization studies were conducted using electronically controlled CWS and pilot accumulator injectors. The most important performance parameters of peak firing pressure, combustion efficiency (coal burnout), and specific fuel comsumption were evaluated in relationship to CWS and pilot injection timing, CWS injector hole size, shape, and number, CWS fuel injection spray angles and injection pressure. Heat release diagrams, as well as exhaust samples (gaseous and particulate), were analyzed for each case. Interesting effects of fuel spray impingement and CWS fuel “Delayed Ignition” were observed. With the engine operating at 2.0 MPa IMEP and 1050 rpm, it was able to obtain over 99.5 percent combustion efficiency while holding the cylinder firing pressure below 17 MPa and thermal efficiency equivalent to diesel fuel operation.

Sign in / Sign up

Export Citation Format

Share Document