An Improvement of Part Load Performance of Diesel Engines Operating at Constant Speed Conditions

Author(s):  
A A Abdel-Rahman ◽  
M K Ibrahim ◽  
A A Said

This paper discusses the possibility of improving the part load performance of diesel electric turbocharged engines operating at constant speed conditions. A sequential turbocharged system is proposed, where the compressors are connected In series. The study focused on two turbocharged diesel–electric generating sets existing at Ameria Petroleum Refining Company in Alexandria, Egypt. The results of the prediction showed that, at part load, both the maximum pressure and temperature were increased, and the brake specific fuel consumption was reduced considerably (by about 10 per cent).

Author(s):  
Olisaemeka C. Nwufo ◽  
Modestus Okwu ◽  
Chidiebere F. Nwaiwu ◽  
Johnson O. Igbokwe ◽  
O. Martin I. Nwafor ◽  
...  

The performance analysis of a single cylinder spark ignition engine fuelled with ethanol – petrol blends were carried out successfully at constant load conditions. E0 (Petrol), E10 (10% Ethanol, 90% Petrol), E20 (20% Ethanol, 80% Petrol) and E30 (30% Ethanol, 70% Petrol) were used as fuel. The Engine speed, mass flow rate, combustion efficiency, maximum pressure developed, brake specific fuel consumption and Exhaust gas temperature values were measured during the experiment. Using the experimental data, a Levenberg Marquardt Artificial Neural Network algorithm and Logistic sigmoid activation transfer function with a 4–10–2 model was developed to predict the brake specific fuel consumption, maximum pressure and combustion efficiency of G200 IMEX spark ignition engine using the recorded engine speed, mass flow rate, biofuels ratio and exhaust gas temperature as input variables. The performance of the Artificial Neural Network was validated by comparing the predicted data with the experimental results. The results showed that the training algorithm of Levenberg Marquardt was sufficient enough in predicting the brake specific fuel consumption, combustion pressure and combustion efficiency of the test engine. Correlation coefficient values of 0.974, 0.996 and 0.995 were obtained for brake specific fuel consumption, combustion efficiency and pressure respectively. These correlation coefficient obtained for the output parameters are very close to one (1) showing good correlation between the Artificial Neural Network predicted results and the experimental data while the Mean Square Errors were found to be very low (0.00018825 @ epoch 10 for brake specific fuel consumption, 1.0023 @ epoch 3 for combustion efficiency and 0.0013284@ epoch 5 for in-cylinder pressure). Therefore, Artificial Neural Network toolbox called up from MATLAB proved to be a useful tool for simulation of engine parameters. Artificial Neural Network model provided accurate analysis of these complex problems and has been found to be very useful for predicting the performance of the spark ignition engine. Thus, this has proved that Artificial Neural Network model could be used for predicting performance values in internal combustion engines, in this way it would be possible to conduct time and cost efficient studies instead of long experimental ones.


2016 ◽  
Vol 18 (8) ◽  
pp. 810-823 ◽  
Author(s):  
Fabio Bozza ◽  
Vincenzo De Bellis ◽  
Luigi Teodosio

Referring to spark-ignition engines, the downsizing, coupled to turbocharging and variable valve actuation systems are very common solutions to reduce the brake-specific fuel consumption at low-medium brake mean effective pressure. However, the adoption of such solutions increases the complexity of engine control and management because of the additional degrees of freedom, and hence results in a longer calibration time and higher experimental efforts. In this work, a twin-cylinder turbocharged variable valve actuation spark-ignition engine is numerically investigated by a one-dimensional model (GT-Power™). The considered engine is equipped with a fully flexible variable valve actuation system, realizing both a common full-lift strategy and a more advanced early intake valve closure strategy. Refined sub-models are used to describe turbulence and combustion processes. In the first stage, one-dimensional engine model is validated against the experimental data at full and part load. The validated model is then integrated in a multipurpose commercial optimizer (modeFRONTIER™) with the aim to identify the engine calibration that minimizes brake-specific fuel consumption at part load. In particular, the decision parameters of the optimization process are the early intake valve closure angle, the throttle valve opening, the turbocharger setting and the spark timing. Proper constraints are posed for intake pressure in order to limit the gas-dynamic noise radiated at the intake mouth. The adopted optimization approach shows the capability to reproduce with good accuracy the experimentally identified calibration. The latter corresponds to the numerically derived Pareto frontier in brake mean effective pressure–brake specific fuel consumption plane. The optimization also underlines the advantages of an engine calibration based on a combination of early intake valve closure strategy and intake throttling rather than a purely throttle-based calibration. The developed automatic procedure allows for a ‘virtual’ calibration of the considered engine on completely theoretical basis and proves to be very helpful in reducing the experimental costs and the engine time-to-market.


REAKTOR ◽  
2017 ◽  
Vol 16 (3) ◽  
pp. 116
Author(s):  
S Syaiful ◽  
S Sobri

Diesel engines have been widely used as a mode of public transport and private vehicles because of several advantages compared to gasoline engines including greater power, fuel economy, high reliability and durability of the engine and lower CO emissions. However, diesel engines release more NOx and soot emissions into the atmosphere. This is a serious problem with the strict regulations regarding exhaust emissions. Besides problems of depletion of fossil fuel reserves require various parties to seek alternative fuels derived diesel fuel. Therefore, this work is intended to reduce soot emissions by adding LPM (low purity methanol) or wet methanol and HPM (high purity methanol) into a mixture of jatropha and diesel fuels. From this research, it is also desirable to observe the effect of methanol additive to the specific fuel consumption. Experiment method was conducted to obtain the correlation between the percentage of methanol to a brake specific fuel consumption (BSFC) and soot emissions. Methanol (LPM and HPM) was varied in the range of 5 to 15% by volume. Jatropha is in the range of 10% to 30%. The rate of EGR (exhaust gas recirculation) expressed by OEV (opening EGR valve) was varied at the opening of 0 to 100%. Engine load was varied from 25 to 100% at intervals of 25%. The engine speed was kept constant of 2000 rpm. The results show that the use of fuel mixture increases evenly BSFC of 5.2% and soot emissions of 65%. Keywords: LPM and HPM, BSFC, soot emissions, jatropha, cold EGR and diesel engine  Abstrak Mesin diesel telah banyak digunakan sebagai moda transportasi umum dan kendaraan pribadi oleh karena beberapa kelebihannya dibandingkan dengan mesin bensin diantaranya daya yang lebih besar, hemat bahan bakar, kehandalan dan ketahanan mesin yang tinggi (high realibility and durability), dan emisi CO yang lebih rendah. Akan tetapi mesin diesel melepaskan lebih banyak emisi NOx dan jelaga ke atmosfir. Hal ini menjadi permasalahan serius dengan semakin ketatnya regulasi menyangkut emisi gas buang. Selain itu permasalahan menipisnya cadangan bahan bakar fosil menuntut berbagai pihak untuk mencari bahan bakar alternatif pengganti solar. Oleh karena itu, penelitian ini bermaksud untuk mereduksi emisi jelaga dengan menambahkan LPM (low purity methanol) atau wet methanol dan HPM (high purity methanol)kedalam campuran bahan bakar jatropha dan solar. Dari penelitian ini juga diinginkan untuk mengamati pengaruh aditif metanol terhadap konsumsi bahan bakar spesifik. Metode eksperimen dilakukan untuk mendapatkan keterkaitan antara prosentase metanol terhadap brake specific fuel consumption (BSFC)dan emisi jelaga. Metanol (LPM dan HPM) divariasikan pada rentang 5% sampai 15%. Jatropha adalah pada rentang 10% sampai 30%. Laju EGR (exhaust gas recirculation) yang dinyatakan oleh OEV (opening EGR valve) divariasikan pada bukaan 0% sampai 100%. Beban mesin divariasikan dari 25% sampai 100% dengan interval 25%. Putaran mesin dipertahankan konstan 2000 rpm. Hasil-hasil penelitian menunjukkan bahwa penggunaan bahan bakar campuran rata-rata meningkatkan BSFC 5,2% dan menurunkan emisi jelaga sampai 65%.


Author(s):  
Evan Pelletier ◽  
Sean Brennan

Abstract The goal of this work is to develop easily generalized models of heavy duty truck engine maps that allow for approximate comparisons of engine performance, thus enabling fuel efficient matching of engines to a set of corresponding loads and routes. This is achieved by applying dimensional analysis to create a uniformly applicable, dimensionless Brake Specific Fuel Consumption (BSFC) map that fits the behavior of a wide range of diesel engines. A commonality between maps was found to occur when engine data is scaled by specific dimensional parameters that target data consistency among the primary operating points across engines. This common map highlights observable trends in engine performance based on the influence of these same parameters being scaled across engines. The resulting dimensionless engine map fits the minimum BSFC regions of four diesel engines to within 2.5 percent.


Author(s):  
Teja Gonguntla ◽  
Robert Raine ◽  
Leigh Ramsey ◽  
Thomas Houlihan

The objective of this project was to develop both engine performance and emission profiles for two test fuels — a 6% water-in-diesel oil emulsion (DOE-6) fuel and a neat diesel (D100) fuel. The testing was performed on a single cylinder, direct-injection, water-cooled diesel engine coupled to an eddy current dynamometer. Output parameters of the engine were used to calculate Brake Specific Fuel Consumption (BSFC) and Engine Efficiency (η) for each test fuel. DOE-6 fuels generated a 24% reduction in NOX and a 42% reduction in Carbon Monoxide emissions over the tested operating conditions. DOE-6 fuels presented higher ignition delays — between 1°-4°, yielded 1%–12% lower peak cylinder pressures and produced up to 5.5% lower exhaust temperatures. Brake Specific Fuel consumption increased by 6.6% for the DOE-6 fuels as compared to the D100 fuels. This project is the first research done by a New Zealand academic institution on water-in-diesel emulsion fuels.


2021 ◽  
Vol 55 (4) ◽  
Author(s):  
Murugan Kuppusamy ◽  
Thirumalai Ramanathan ◽  
Udhayakumar Krishnavel ◽  
Seenivasan Murugesan

The effect of thermal-barrier coatings (TBCs) reduces fuel consumption, effectively improving the engine efficiency. This research focused on a TBC with a thickness of 300 µm insulating the combustion chamber of a direct ignition (DI) engine. The piston crown, inlet and exhaust-valve head were coated using air-plasma-spray coating. Ceramic powder materials such as molybdenum (Mo) and aluminum oxide titanium dioxide (Al2O3-TiO2) were used. A performance test of the engine with the coated combustion chamber was carried out to investigate the brake power, brake thermal efficiency, volumetric efficiency, brake specific fuel consumption and air-fuel ratio. Also, an emission-characteristic test was carried out to investigate the emissions of unburned hydrocarbon (HC), carbon monoxide (CO), nitrogen oxides (NO, NO2, NO3) and smoke opacity (SO). The results reveal that the brake thermal efficiency and brake specific fuel consumption show significant increases because of these coating materials. The effect of the Al2O3-TiO2 coating significantly reduces the HC and CO engine emissions.


2014 ◽  
Vol 490-491 ◽  
pp. 987-991
Author(s):  
Mustafa Kaan Baltacioğlu ◽  
Kadi̇r Aydin ◽  
Ergül Yaşar ◽  
Hüseyi̇n Turan Arat ◽  
Çağlar Conker ◽  
...  

In this study, effect of anisole additive into the diesel fuel on performance and emission parameters of diesel engines was investigated. Instead of structural changes which are more difficult and expensive, development of fuel technologies is preferred to provide reduction on exhaust gas emissions which are harmful to environment and human health. Therefore, in this experimental study, anisole was used as additive into diesel fuel with the volumetric ratio of 1,5%, 3% and 5%. The performance characteristics and exhaust emissions of a four cylinder, four stroke, naturally aspirated, water cooled, direct injection compression ignition engine fueled with modified fuels were analyzed. Engine was subjected constant speed, full load conditions during tests. Engine power, torque, specific fuel consumption, carbon monoxide, nitrogen oxide and carbon dioxide emissions were measured and results were evaluated. Changes in performance parameters were negligible for all ratios of modified fuels except specific fuel consumption. Finally, while carbon monoxide gas emissions were increased with anisole additive, carbon dioxide and nitrogen oxide gas emissions were decreased.


2015 ◽  
Vol 730 ◽  
pp. 283-286
Author(s):  
Rong Fu Zhu ◽  
Yun Long Wang ◽  
Hui Wang ◽  
Yuan Tao Sun

The performance of engine fueled with diesel/biodiesel blends was tested. It was indicated from the experimental results that the brake power, torque out and brake specific fuel consumption of engine fueled with diesel/biodiesel caused slight variations, while NOx emission increased significantly compared with engine fueled with diesel. In order to reduce NOx emission of engine fueled with pure biodiesel, retarding fuel delivery advance angle was used, and the NOx emission tests revealed that the NOx emission decreased significantly at different engine speeds.


2017 ◽  
Vol 21 (1 Part B) ◽  
pp. 555-566 ◽  
Author(s):  
Feyyaz Candan ◽  
Murat Ciniviz ◽  
Ilker Ors

In this study, methanol in ratios of 5-10-15% were incorporated into diesel fuel with the aim of reducing harmful exhaust gasses of Diesel engine, di-tertbutyl peroxide as cetane improver in a ratio of 1% was added into mixture fuels in order to reduce negative effects of methanol on engine performance parameters, and isobutanol of a ratio of 1% was used as additive for preventing phase separation of all mixtures. As results of experiments conducted on a single cylinder and direct injection Diesel engine, methanol caused the increase of NOx emission while reducing CO, HC, CO2, and smoke opacity emissions. It also reduced torque and power values, and increased brake specific fuel consumption values. Cetane improver increased torque and power values slightly compared to methanol-mixed fuels, and reduced brake specific fuel consumption values. It also affected exhaust emission values positively, excluding smoke opacity. Increase of injector injection pressure affected performances of methanol-mixed fuels positively. It also increased injection pressure and NOx emissions, while reducing other exhaust emissions.


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