scholarly journals Study of Using Oxygen-Enriched Combustion Air for Locomotive Diesel Engines

2000 ◽  
Vol 123 (1) ◽  
pp. 157-166 ◽  
Author(s):  
D. N. Assanis ◽  
R. B. Poola ◽  
R. Sekar ◽  
G. R. Cataldi
Keyword(s):  
Oxygen Content ◽  
Diesel Engines ◽  
Oxygen Enrichment ◽  
Air Separation ◽  
Injection Timing ◽  
Full Potential ◽  
Cylinder Pressure ◽  
Peak Cylinder Pressure ◽  
Locomotive Diesel ◽  
No Emissions

A thermodynamic simulation is used to study the effects of oxygen-enriched intake air on the performance and nitrogen oxide (NO) emissions of a locomotive diesel engine. The parasitic power of the air separation membrane required to supply the oxygen-enriched air is also estimated. For a given constraint on peak cylinder pressure, the gross and net power output of an engine operating under different levels of oxygen enrichment are compared with those obtained when a high-boost turbocharged engine is used. A 4 percent increase in peak cylinder pressure can result in an increase in net engine power of approximately 10 percent when intake air with an oxygen content of 28 percent by volume is used and fuel injection timing is retarded by 4 degrees. When the engine is turbocharged to a higher inlet boost, the same increase in peak cylinder pressure can improve power by only 4 percent. If part of the significantly higher exhaust enthalpies available as a result of oxygen enrichment is recovered, the power requirements of the air separator membrane can be met, resulting in substantial net power improvements. Oxygen enrichment with its attendant higher combustion temperatures, reduces emissions of particulates and visible smoke but increases NO emissions (by up to three times at 26 percent oxygen content). Therefore, exhaust gas after-treatment and heat recovery would be required if the full potential of oxygen enrichment for improving the performance of locomotive diesel engines is to be realized.

A Signal Processing of In-Cylinder Pressure for the Resonant Frequency Prediction of Combustion Process in Diesel Engines

2018 ◽  
Author(s):  
Ximing Chen ◽  
Long Liu ◽  
Jiguang Zhang ◽  
Jingtao Du
Keyword(s):  
Signal Processing ◽  
Fourier Transform ◽  
Wavelet Transform ◽  
Resonant Frequency ◽  
Diesel Engines ◽  
Combustion Process ◽  
Combustion Noise ◽  
Injection Timing ◽  
Cylinder Pressure ◽  
Empirical Wavelet Transform

The combustion resonance is a focal point of the analysis of combustion and thermodynamic processes in diesel engines, such as detecting ‘knock’ and predicting combustion noise. Combustion resonant frequency is also significant for the estimation of in-cylinder bulk gas temperature and trapped mass. Normally, the resonant frequency information is contained in in-cylinder pressure signals. Therefore, the in-cylinder pressure signal processing is used for resonant frequency calculation. Conventional spectral analyses, such as FFT (Fast Fourier transform), are unsuitable for processing in-cylinder pressure signals because of its non-stationary characteristic. Other approaches to deal with non-stationary signals are Short-Time Fourier Transform (STFT) and Continue Wavelet Transform (CWT). However, the choice of size and shape of window for STFT and the selection of wavelet basis for CWT are totally empirical, which is the limit for precisely calculating the resonant frequency. In this study, an approach based on Empirical Wavelet Transform (EWT) and Hilbert Transform (HT) is proposed to process in-cylinder pressure signals and extract resonant frequencies. In order to decompose in-cylinder pressure spectrum precisely, the EWT are applied for separating the frequency band corresponding combustion resonance mode from other irrelevant modes adaptively. The signals containing combustion resonant mode is processed by HT, so that the instantaneous resonant frequency and amplitude can be extracted. Validation is performed by four in-cylinder pressure signals with different injection timing. And the effects of injection timing on resonant frequency are discussed.

scholarly journals Locomotive Diesel Engine Excess Air Ratio Control Device

2019 ◽  
Vol 8 (4) ◽  
pp. 7716-7719
Keyword(s):  
Diesel Engine ◽  
Control Systems ◽  
Oxygen Content ◽  
Diesel Engines ◽  
Continuous Monitoring ◽  
Wide Band ◽  
Control Device ◽  
Exhaust Gases ◽  
Excess Air ◽  
Locomotive Diesel

The wide-band exhaust gases oxygen content sensor can be used for continuous monitoring of the air excess coefficient in the locomotive diesel engine cylinders. This type sensors are widely used in automotive diesel engines control systems. It means for indirect estimation of the engine cylinders mixture quality by the exhaust gases oxygen content

Effect of Low-Sulfur Fuel on Auxiliary Engine Combustion and Performance

2021 ◽  
Author(s):  
Theofanis Chountalas ◽  
Maria Founti
Keyword(s):  
Combustion Rate ◽  
Diesel Engines ◽  
Engine Performance ◽  
Operating Conditions ◽  
Injection System ◽  
Combustion Mechanism ◽  
Injection Timing ◽  
Cylinder Pressure ◽  
Marine Diesel ◽  
And Performance

According to the current legislation, since 01/01/2020 it is necessary to operate marine diesel engines in a wide range of areas using MGO (Marine Gas Oil). Currently, most marine diesel engines operate on HSFO (High Sulfur Fuel Oil). In the present work the effect of MGO and HSFO on the combustion mechanism and performance of Marine Diesel Auxiliary Engines is investigated. This can be accomplished via comparative evaluation of operational parameters and net combustion rate at various engine operating conditions. In this work, performance evaluation is based on the processing of measured engine cylinder pressure data acquired at sea using both fuel types. The measured cylinder pressure traces are analyzed to determine the net combustion rate, ignition delay, dynamic start of fuel injection timing, injection-combustion quality and combustion duration. Final analysis confirmed that there is considerable impact of the fuel type on engine performance and the combustion mechanism. Due to the high rotational speed of auxiliary engines, alterations in engine operation and especially the different dynamic response of the injection system between the two fuel types, led to measurably deviating engine performance, akin to different engine tuning. Severity of fuel effect was found dependent on engine type and especially condition.

Abrasive Wear of Piston Grooves of Highly Loaded Diesel Engines

Volume 1 ◽  
2004 ◽  
Author(s):  
Nagaraj Nayak ◽  
P. A. Lakshminarayanan ◽  
M. K. Gajendra Babu ◽  
A. D. Dani
Keyword(s):  
Abrasive Wear ◽  
Diesel Engines ◽  
Cylinder Pressure ◽  
Oil Consumption ◽  
Depth Of Penetration ◽  
Groove Surface ◽  
Air Filter ◽  
Abrasive Particles ◽  
Hard Particles ◽  
Peak Cylinder Pressure

The rate of wear of piston grooves on the piston is mainly a function of the peak cylinder pressure, hardness, surface roughness, depth of penetration and the number of hard particles produced by combustion or entering past the air filter. The problem of wear becomes severe as the blowby past the rings and oil consumption of the engine increases in diesel engines. In this paper, an attempt is made to estimate the wear of piston grooves quantitatively. The wear rate is correlated with the product of gaseous load, amount of hard particles past the piston lands, radius of abrasive particles, and inversely with hardness of the groove surface. Under abnormal conditions, the shear strain due to friction exceeds the plasticity limit of the material and superficial delamination occurs at the groove surface. The model was validated on a large bore engine running on heavy fuel at 22-bar bmep and the abrasive wear predicted by other earlier models are discussed [7].

scholarly journals Evaluation of a Semiempirical, Zero-Dimensional, Multizone Model to Predict Nitric Oxide Emissions in DI Diesel Engines’ Combustion Chamber

2016 ◽  
Vol 2016 ◽  
pp. 1-14 ◽  
Author(s):  
Nicholas S. Savva ◽  
Dimitrios T. Hountalas
Keyword(s):  
Nitric Oxide ◽  
Diesel Engines ◽  
Fuel Injection ◽  
Operating Conditions ◽  
Injection Timing ◽  
Boost Pressure ◽  
Cylinder Pressure ◽  
No Formation ◽  
Calculation Step ◽  
Multizone Model

In the present study, a semiempirical, zero-dimensional multizone model, developed by the authors, is implemented on two automotive diesel engines, a heavy-duty truck engine and a light-duty passenger car engine with pilot fuel injection, for various operating conditions including variation of power/speed, EGR rate, fuel injection timing, fuel injection pressure, and boost pressure, to verify its capability for Nitric Oxide (NO) emission prediction. The model utilizes cylinder’s basic geometry and engine operating data and measured cylinder pressure to estimate the apparent combustion rate which is then discretized into burning zones according to the calculation step used. The requisite unburnt charge for the combustion in the zones is calculated using the zone equivalence ratio provided from a new empirical formula involving parameters derived from the processing of the measured cylinder pressure and typical engine operating parameters. For the calculation of NO formation, the extended Zeldovich mechanism is used. From this approach, the model is able to provide the evolution of NO formation inside each burned zone and, cumulatively, the cylinder’s NO formation history. As proven from the investigation conducted herein, the proposed model adequately predicts NO emissions and NO trends when the engine settings vary, with low computational cost. These encourage its use for engine control optimization regarding NOxabatement and real-time/model-based NOxcontrol applications.

Effect of Fuel Injection Timing and Injection Pressure on Combustion and Odorous Emissions in DI Diesel Engines

2009 ◽  
Vol 131 (3) ◽  
Author(s):  
Murari Mohon Roy
Keyword(s):  
Ignition Delay ◽  
Fuel Injection ◽  
Direct Injection ◽  
Injection Pressure ◽  
Injection Timing ◽  
Cylinder Pressure ◽  
Warm Up ◽  
Fuel Injection Timing ◽  
Peak Cylinder Pressure ◽  
Injection Pressures

This study investigated the effect of fuel injection timing and injection pressure on combustion and odorous emissions in a direct injection diesel engine. Injection timings from 15 deg before top dead center (BTDC) to top dead center (TDC) and injection pressures from 20 MPa to 120 MPa were tested. In emissions, exhaust odor, irritation, aldehydes, total hydrocarbon, and hydrocarbon components are compared in different injection timings and injection pressures condition. Injection timings where main combustion takes place very close to TDC are found to show minimum odorous emissions. Moderate injection pressures (60–80 MPa) showed lower emissions including odor and irritation due to proper mixture formation. Below the injection pressure of 40 MPa, and over 80 MPa, emissions become worse. Combustion analysis is performed by taking cylinder pressures after engine warm-up for different injection timings and injection pressures and analyzing cylinder temperatures and heat release rates. Cylinder pressures and temperatures are gradually decreased when injection timings are retarded. Ignition delay becomes shortest at 5–10 deg BTDC injection timings. The peak cylinder pressure and temperature are increased with higher injection pressures. The shortest ignition delay and minimum emissions is found at around 60 MPa of injection pressure.

Experimental Study on Combustion and Performance of a Natural Gas-Diesel Dual-Fuel Engine at Different Pilot Diesel Injection Timing

2020 ◽  
Vol 12 (5) ◽  
Author(s):  
Jiantong Song ◽  
Zhixin Feng ◽  
Jiangyi Lv ◽  
Hualei Zhang
Keyword(s):  
Natural Gas ◽  
Pressure Rise ◽  
Mean Value ◽  
Dual Fuel ◽  
Injection Timing ◽  
Cylinder Pressure ◽  
Diesel Injection ◽  
Peak Cylinder Pressure ◽  
Crank Angle ◽  
And Performance

Abstract The pilot diesel injection timing (θ) significantly affects the combustion and performance of dual-fuel (DF) engines. In order to optimize the θ of a natural gas-diesel DF engine, the influence of θ on combustion, cyclic variation, and performance of a diesel engine fueled with natural gas piloted by diesel under full load at 1200 rpm was investigated. The results indicate that, with the advance in θ, the cylinder pressure, rate of pressure rise (ROPR), and heat release rate (HRR) increase first and then decrease. The mean value of peak cylinder pressure (pmax) rises and the standard deviation increases first and then decreases. The distribution of the crank angle of peak cylinder pressure (φ(pmax)) scatters and approaches the top dead center. The coefficient of variation (COV) in pmax decreases first and then increases while the COV in φ(pmax) obviously increases. The brake power increases first and then decreases while the brake specific fuel consumption (b.s.f.c.) reduces first and then rises. The CO2 and NOx emissions rise first and then reduce while smoke emission decreases first and then increases, but the CO and HC rise.

Experimental Study on the Influence of Injection Timing on Combustion and Emission of Biodiesel Engine Based on Mechanical Mechanics

2014 ◽  
Vol 908 ◽  
pp. 301-309
Author(s):  
Di Ming Lou ◽  
Yang Wu ◽  
Zhi Yuan Hu ◽  
Pi Qiang Tan ◽  
Jian Jun Lin
Keyword(s):  
Experimental Study ◽  
Maximum Rate ◽  
Peak Pressure ◽  
Injection Timing ◽  
Emission Characteristics ◽  
Cylinder Pressure ◽  
Full Load ◽  
Combustion Duration ◽  
Peak Cylinder Pressure ◽  
Load Peak

This article investigates the effect of different injection timings on the combustion and emission characteristics of a Chinese V high pressure common rail diesel engine fuelled with blends of biodiesel and diesel (the volume ration of biodiesel is 20%). The Results show that, retarded injection timing resulted in decrease of ignition delay and combustion duration at all loads, except for 25 percent of full load. Peak cylinder pressure and maximum rate of peak pressure significantly reduced at retarded injection timing. The cycle-by-cycle variation of peak cylinder pressure first increased and then decreased, and the highest was obtained at -4°CA of injection timing. BSFC increased by 0.3% to 4.2% with retarded injection timing. Postponing injection timing effectively reduced NOx emission. NOx and PM emissions simultaneously decreased at full load when postponing injection. At 25% load HC and CO emissions were significantly higher than other loads and the effect of injection timing was most obvious.

scholarly journals Effect of Injection Timing and Injection Duration of Manifold Injected Fuels in Reactivity Controlled Compression Ignition Engine Operated with Renewable Fuels

Energies ◽  
2021 ◽  
Vol 14 (15) ◽  
pp. 4621
Author(s):  
P. A. Harari ◽  
N. R. Banapurmath ◽  
V. S. Yaliwal ◽  
T. M. Yunus Khan ◽  
Irfan Anjum Badruddin ◽  
...  
Keyword(s):  
Nitric Oxide ◽  
Injection Timing ◽  
Compression Ignition ◽  
Cylinder Pressure ◽  
Compression Ignition Engine ◽  
Compressed Natural Gas ◽  
Reactivity Controlled Compression Ignition ◽  
Brake Thermal Efficiency ◽  
Injection Duration ◽  
Fuel Mixtures

In the current work, an effort is made to study the influence of injection timing (IT) and injection duration (ID) of manifold injected fuels (MIF) in the reactivity controlled compression ignition (RCCI) engine. Compressed natural gas (CNG) and compressed biogas (CBG) are used as the MIF along with diesel and blends of Thevetia Peruviana methyl ester (TPME) are used as the direct injected fuels (DIF). The ITs of the MIF that were studied includes 45°ATDC, 50°ATDC, and 55°ATDC. Also, present study includes impact of various IDs of the MIF such as 3, 6, and 9 ms on RCCI mode of combustion. The complete experimental work is conducted at 75% of rated power. The results show that among the different ITs studied, the D+CNG mixture exhibits higher brake thermal efficiency (BTE), about 29.32% is observed at 50° ATDC IT, which is about 1.77, 3.58, 5.56, 7.51, and 8.54% higher than D+CBG, B20+CNG, B20+CBG, B100+CNG, and B100+CBG fuel combinations. The highest BTE, about 30.25%, is found for the D+CNG fuel combination at 6 ms ID, which is about 1.69, 3.48, 5.32%, 7.24, and 9.16% higher as compared with the D+CBG, B20+CNG, B20+CBG, B100+CNG, and B100+CBG fuel combinations. At all ITs and IDs, higher emissions of nitric oxide (NOx) along with lower emissions of smoke, carbon monoxide (CO), and hydrocarbon (HC) are found for D+CNG mixture as related to other fuel mixtures. At all ITs and IDs, D+CNG gives higher In-cylinder pressure (ICP) and heat release rate (HRR) as compared with other fuel combinations.

scholarly journals A Numerical Study on the Combustion Process and Emission Characteristics of a Natural Gas-Diesel Dual-Fuel Marine Engine at Full Load

Energies ◽  
2021 ◽  
Vol 14 (5) ◽  
pp. 1342
Author(s):  
Van Chien Pham ◽  
Jae-Hyuk Choi ◽  
Beom-Seok Rho ◽  
Jun-Soo Kim ◽  
Kyunam Park ◽  
...  
Keyword(s):  
Natural Gas ◽  
Combustion Process ◽  
Simulation Software ◽  
Dual Fuel ◽  
Injection Timing ◽  
Emission Characteristics ◽  
Cylinder Pressure ◽  
Marine Engine ◽  
Full Load ◽  
Simulation Results

This paper presents research on the combustion and emission characteristics of a four-stroke Natural gas–Diesel dual-fuel marine engine at full load. The AVL FIRE R2018a (AVL List GmbH, Graz, Austria) simulation software was used to conduct three-dimensional simulations of the combustion process and emission formations inside the engine cylinder in both diesel and dual-fuel mode to analyze the in-cylinder pressure, temperature, and emission characteristics. The simulation results were then compared and showed a good agreement with the measured values reported in the engine’s shop test technical data. The simulation results showed reductions in the in-cylinder pressure and temperature peaks by 1.7% and 6.75%, while NO, soot, CO, and CO2 emissions were reduced up to 96%, 96%, 86%, and 15.9%, respectively, in the dual-fuel mode in comparison with the diesel mode. The results also show better and more uniform combustion at the late stage of the combustions inside the cylinder when operating the engine in the dual-fuel mode. Analyzing the emission characteristics and the engine performance when the injection timing varies shows that, operating the engine in the dual-fuel mode with an injection timing of 12 crank angle degrees before the top dead center is the best solution to reduce emissions while keeping the optimal engine power.

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