scholarly journals Engine Manifold Wave Action under Variable Stroke Length

2017 ◽  
Vol 11 (8) ◽  
pp. 79
Author(s):  
Jehad Ahmad Yamin
Keyword(s):  
Diesel Engine ◽  
Pressure Wave ◽  
Direct Injection ◽  
Engine Performance ◽  
Wave Action ◽  
Pressure Waves ◽  
Valve Timing ◽  
Stroke Length ◽  
Piston Bowl ◽  
Wide Range

A theoretical investigation on the pressure wave action of the manifolds of a four-stroke, direct injection (hereinafter referred to as DI), water-cooled, 4-stroke, diesel engine with variable stroke length was carried out.  The study was conducted over wide range of speeds (1000 - 3000 RPM at an increment of 500 RPM) and stroke lengths (130 mm to 210 mm at an increment of 20mm). The compression ratio was kept constant by adjusting the piston bowl volume. The study showed that shorter stroke lengths created favorable pressure waves in both inlet and exhaust manifolds at lower speeds, which resulted in improved engine volumetric and thermal efficiencies. At higher speeds, the larger strokes were favorable, however, due to less time available for the suction and exhaust strokes to be executed, the efficiencies were low. Advancing valve timing was one factor that improved the engine performance with larger stroke lengths.

scholarly journals Response Surface Modelling of Diesel Engine Emissions under Variable Stroke Length and Constant Compression Ratio

2018 ◽  
Vol 12 (10) ◽  
pp. 36
Author(s):  
Jehad A. A. Yamin
Keyword(s):  
Diesel Engine ◽  
Compression Ratio ◽  
Direct Injection ◽  
Statistical Technique ◽  
Stroke Length ◽  
Piston Bowl ◽  
Wide Range ◽  
Injection Water ◽  
Response Surface Modelling ◽  
Relative Change

A theoretical investigation using RSM statistical technique on the relative change of emissions of a four-stroke, direct injection, water-cooled, 4-stroke, diesel engine with variable stroke length was carried out.  The performance parameters were studied over wide range of speeds (1000 - 3000 RPM at an increment of 500 RPM) and stroke lengths (130 mm to 210mm at an increment of 20mm). The compression ratio was kept constant by adjusting the piston bowl volume. It was found within the range of stroke length studied, that larger stroke lengths are favorable for lower NOx and specific CO2 emissions. This is due to the lower availability of Oxygen. As for specific PM and BSN, the shorter the stroke length the lower the levels. This is attributed to improved engine charging efficiency, hence, better availability of oxygen.

scholarly journals Influence of narrow fuel spray angle and split injection strategies on combustion efficiency and engine performance in a common rail direct injection diesel engine

2016 ◽  
Vol 9 (1) ◽  
pp. 71-81 ◽  
Author(s):  
Raouf Mobasheri
Keyword(s):  
Diesel Engine ◽  
Direct Injection ◽  
Engine Performance ◽  
Spray Angle ◽  
Fuel Spray ◽  
Multiple Injection ◽  
Split Injection ◽  
Direct Injection Diesel Engine ◽  
Piston Bowl ◽  
Injection Strategies

Direct injection diesel engines have been widely used in transportation and stationary power systems because of their inherent high thermal efficiency. On the other hand, emission regulations such as NOx and particulates have become more stringent from the standpoint of preserving the environment in recent years. In this study, previous results of multiple injection strategies have been further investigated to analyze the effects of narrow fuel spray angle on optimum multiple injection schemes in a heavy duty common rail direct injection diesel engine. An advanced computational fluid dynamics simulation has been carried out on a Caterpillar 3401 diesel engine for a conventional part load condition in 1600 r/min at two exhaust gas recirculation rates. A good agreement of calculated and measured in-cylinder pressure, heat release rate and pollutant formation trends was obtained under various operating points. Three different included spray angles have been studied in comparison with the traditional spray injection angle. The results show that spray targeting is very effective for controlling the in-cylinder mixture distributions especially when it accompanied with various injection strategies. It was found that the optimum engine performance for simultaneous reduction of soot and NOx emissions was achieved with 105° included spray angle along with an optimized split injection strategy. The results show, in this case, the fuel spray impinges at the edge of the piston bowl and a counterclockwise flow motion is generated that pushes mixture toward the center of the piston bowl.

scholarly journals THE EFFECT OF DIESEL-BIODIESEL BLENDS ON THE PERFORMANCE AND EXHAUST EMISSIONS OF A DIRECT INJECTION OFF-ROAD DIESEL ENGINE

Transport ◽  
2014 ◽  
Vol 29 (4) ◽  
pp. 440-448 ◽  
Author(s):  
Tomas Mickevičius ◽  
Stasys Slavinskas ◽  
Slawomir Wierzbicki ◽  
Kamil Duda
Keyword(s):  
Diesel Engine ◽  
Diesel Fuel ◽  
Direct Injection ◽  
Engine Performance ◽  
Exhaust Emissions ◽  
Bench Test ◽  
Maximum Pressure ◽  
Cylinder Pressure ◽  
Biodiesel Blends ◽  
Performance And Emission

This paper presents a comparative analysis of the diesel engine performance and emission characteristics, when operating on diesel fuel and various diesel-biodiesel (B10, B20, B40, B60) blends, at various loads and engine speeds. The experimental tests were performed on a four-stroke, four-cylinder, direct injection, naturally aspirated, 60 kW diesel engine D-243. The in-cylinder pressure data was analysed to determine the ignition delay, the Heat Release Rate (HRR), maximum in-cylinder pressure and maximum pressure gradients. The influence of diesel-biodiesel blends on the Brake Specific Fuel Consumption (bsfc) and exhaust emissions was also investigated. The bench test results showed that when the engine running on blends B60 at full engine load and rated speed, the autoignition delay was 13.5% longer, in comparison with mineral diesel. Maximum cylinder pressure decreased about 1–2% when the amount of Rapeseed Methyl Ester (RME) expanded in the diesel fuel when operating at full load and 1400 min–1 speed. At rated mode, the minimum bsfc increased, when operating on biofuel blends compared to mineral diesel. The maximum brake thermal efficiency sustained at the levels from 0.3% to 6.5% lower in comparison with mineral diesel operating at full (100%) load. When the engine was running at maximum torque mode using diesel – RME fuel blends B10, B20, B40 and B60 the total emissions of nitrogen oxides decreased. At full and moderate load, the emission of carbon monoxide significantly raised as the amount of RME in fuel increased.

Experimental Investigations of Performance and Emission Characteristics of Moringa Oil Methyl Ester and Its Diesel Blends in a Single Cylinder Direct Injection Diesel Engine

2009 ◽  
Author(s):  
Shyamsundar Rajaraman ◽  
G. K. Yashwanth ◽  
T. Rajan ◽  
R. Siva Kumaran ◽  
P. Raghu
Keyword(s):  
Diesel Engine ◽  
Alternative Fuels ◽  
Methyl Esters ◽  
Direct Injection ◽  
Engine Performance ◽  
Experimental Investigations ◽  
Emission Analysis ◽  
Performance And Emission ◽  
Direct Injection Diesel Engine ◽  
Moringa Oil

World at present is confronted with the twin crisis of fossil fuel depletion and environmental pollution. Rapid escalation in prices and hydrocarbon resources depletion has led us to look for alternative fuels, which can satisfy ever increasing demands of energy as well as protect the environment from noxious pollutants. In this direction an attempt has been made to study a biodiesel, namely Moringa Oil Methyl Esters [MOME]. All the experiments were carried out on a 4.4 kW naturally aspirated stationary direct injection diesel engine coupled with a dynamometer to determine the engine performance and emission analysis for MOME. It was observed that there was a reduction in HC, CO and PM emissions along with a substantial increase in NOx. MOME and its blends had slightly lower thermal efficiency than diesel oil.

Analysis of Throttle Opening Variation Impact on a Diesel Engine Performance Using Second Law of Thermodynamics

2009 ◽  
Author(s):  
B. B. Sahoo ◽  
U. K. Saha ◽  
N. Sahoo ◽  
P. Prusty
Keyword(s):  
Diesel Engine ◽  
Direct Injection ◽  
Fuel Efficiency ◽  
Engine Performance ◽  
Second Law Of Thermodynamics ◽  
Operating Conditions ◽  
Second Law ◽  
Engine Fuel ◽  
Availability Analysis ◽  
Second Law Analysis

The fuel efficiency of a modern diesel engine has decreased due to the recent revisions to emission standards. For an engine fuel economy, the engine speed is to be optimum for an exact throttle opening (TO) position. This work presents an analysis of throttle opening variation impact on a multi-cylinder, direct injection diesel engine with the aid of Second Law of thermodynamics. For this purpose, the engine is run for different throttle openings with several load and speed variations. At a steady engine loading condition, variation in the throttle openings has resulted in different engine speeds. The Second Law analysis, also called ‘Exergy’ analysis, is performed for these different engine speeds at their throttle positions. The Second Law analysis includes brake work, coolant heat transfer, exhaust losses, exergy efficiency, and airfuel ratio. The availability analysis is performed for 70%, 80%, and 90% loads of engine maximum power condition with 50%, 75%, and 100% TO variations. The data are recorded using a computerized engine test unit. Results indicate that the optimum engine operating conditions for 70%, 80% and 90% engine loads are 2000 rpm at 50% TO, 2300 rpm at 75% TO and 3250 rpm at 100% TO respectively.

scholarly journals Modification of a Direct Injection Diesel Engine in Improving the Ignitability and Emissions of Diesel–Ethanol–Palm Oil Methyl Ester Blends

Energies ◽  
2019 ◽  
Vol 12 (14) ◽  
pp. 2644 ◽  
Author(s):  
Norhidayah Mat Taib ◽  
Mohd Radzi Abu Mansor ◽  
Wan Mohd Faizal Wan Mahmood
Keyword(s):  
Diesel Engine ◽  
Methyl Ester ◽  
Ambient Temperature ◽  
Palm Oil ◽  
Compression Ratio ◽  
Direct Injection ◽  
Cetane Number ◽  
Engine Performance ◽  
Injection Timing ◽  
Injection Strategies

Blending diesel with biofuels, such as ethanol and palm oil methyl ester (PME), enhances the fuel properties and produces improved engine performance and low emissions. However, the presence of ethanol, which has a small cetane number and low heating value, reduces the fuel ignitability. This work aimed to study the effect of injection strategies, compression ratio (CR), and air intake temperature (Ti) modification on blend ignitability, combustion characteristics, and emissions. Moreover, the best composition of diesel–ethanol–PME blends and engine modification was selected. A simulation was also conducted using Converge CFD software based on a single-cylinder direct injection compression ignition Yanmar TF90 engine parameter. Diesel–ethanol–PME blends that consist of 10% ethanol with 40% PME (D50E10B40), D50E25B25, and D50E40B10 were selected and conducted on different injection strategies, compression ratios, and intake temperatures. The results show that shortening the injection duration and increasing the injected mass has no significant effect on ignition. Meanwhile, advancing the injection timing improves the ignitability but with weak ignition energy. Therefore, increasing the compression ratio and ambient temperature helps ignite the non-combustible blends due to the high temperature and pressure. This modification allowed the mixture to ignite with a minimum CR of 20 and Ti of 350 K. Thus, blending high ethanol contents in a diesel engine can be applied by advancing the injection, increasing the CR, and increasing the ambient temperature. From the emission comparison, the most suitable mixtures that can be operated in the engine without modification is D50E25B25, and the most appropriate modification on the engine is by increasing the ambient temperature at 350 K.

scholarly journals Performance Analysis of Direct Injection Diesel Engine Fueled with Diesel-Tomato Seed Oil Biodiesel Blending by ANOVA and ANN

Energies ◽  
2019 ◽  
Vol 12 (23) ◽  
pp. 4421 ◽  
Author(s):  
Karami ◽  
Rasul ◽  
Khan ◽  
Anwar
Keyword(s):  
Diesel Engine ◽  
Performance Analysis ◽  
Direct Injection ◽  
Engine Performance ◽  
Gas Temperature ◽  
Ann Model ◽  
Tomato Seed ◽  
Significance Level ◽  
Di Diesel Engine ◽  
Biodiesel Fuels

Biodiesel is an alternative fuel for diesel engine. Considering the differences between diesel and biodiesel fuels, the engine condition should be modified based on the fuel or fuel blends to achieve optimum performance. This study presented a performance analysis of a direct-injected (DI) diesel engine with a dynamometer fueled with diesel-tomato seed biodiesel (TSOB) blends employing ANOVA and universal nonlinear model based on ANN. The experiments were carried out under conditions of some independent variables including different engine loads (0, 50, 100%) and speed (1800, 2150, and 2500 rpm) for four diesel-biodiesel combinations (B0, B5, B10, and B20). In this research, the effect of these factors on dependent variables including power, torque, SFC, FC, and Exhaust Gas Temperature (EGT) are investigated. Duncan′s multi-domain test at a significance level of R < 0.01 shows that the highest and lowest of the torque and power are produced from B5 and B20, respectively. These results show that the lowest EGT of 613 K is related to B20 and the highest EGT is related to B5 and B10. The regression models showed that the torque decreases with increasing the engine speed and biodiesel percentage. These results also show that the highest and the lowest SFC is related to B0 and B20, respectively. The ANN model shows high capability of predicting the engine performance parameters and emissions, without running costly and time-consuming experiments with the histogram error of 0.004 and R = 0.96. It also proved that ANN is a non-linear model of choice to deal with these data, instead of multivariate linear regression employed for preliminary analysis.

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