scholarly journals Influence of Ethanol-Gasoline Fuel Fractions on Variable Compression Ratio Engine

2019 ◽  
Vol 8 (3) ◽  
pp. 2929-2936
Keyword(s):  
Compression Ratio ◽  
Gasoline Engine ◽  
Engine Performance ◽  
Calorific Value ◽  
Mechanical Efficiency ◽  
Spark Ignition Engine ◽  
Brake Thermal Efficiency ◽  
Variable Compression Ratio Engine ◽  
Power Outputs ◽  
Fuel Fraction

Increase in demand of ethanol as blending fuel with gasoline is increasing. For noting the performance of the engine, experimentations are required to be done on engine, fuelled with various percentages of ethanol in gasoline. In this study, fuel fractions of ethanol and gasoline were taken for observing the performance of spark ignition engine. One-cylinder gasoline engine was used for conducting the experiments and to analyse the effects of ethanol-gasoline fuel fraction on performance of the engine. The engine was tested at Full Open Throttle condition. The load on the engine was changed by changing the load on Eddy Current Dynamometer to vary the engine speed from 1300 to 1700 rpm in the interval of 100 rpm. Gasoline is blended with ethanol to make five fuel fractions from 0 % ethanol (E0) to 40 % ethanol (E40) in gasoline at the interval of 10% by volume. Engine performance was observed at various Compression Ratio (CR) of the engine as 7,8,9 and 10. Calorific Value (CV) of the fuel fractions observed decreasing from E0 to E40 as CV of ethanol is less than base gasoline. Increase in Brake Specific Fuel Consumption was not very significant with rise in ethanol percentage. Power outputs in terms of Brake Power (BP) was increasing with increase in speed of the engine and observed decreasing with increase in ethanol percentage at constant CR. However various engine output parameters like BP, Mechanical Efficiency found decreasing with increase in fuel fractions ratio. Brake Thermal Efficiency (BTE) was observed decreasing with increase in fuel fractions. However, BTE was observed increasing with increase in CR.

Application of Over-Expansion Cycle to a Larger Gasoline Engine With Late-Closing of Intake Valves

2002 ◽  
Author(s):  
Seiichi Shiga ◽  
Kenji Nishida ◽  
Shizuo Yagi ◽  
Youichi Miyashita ◽  
Yoshiharu Yuzawa ◽  
...  
Keyword(s):  
Compression Ratio ◽  
Thermal Efficiency ◽  
Gasoline Engine ◽  
Engine Performance ◽  
Mechanical Efficiency ◽  
Expansion Ratio ◽  
Brake Thermal Efficiency ◽  
Gasoline Engines ◽  
Cylinder Test ◽  
Test Engine

This paper presents further investigation into the effect of over-expansion cycle with late-closing of intake valves on the engine performance in gasoline engines. A larger single-cylinder test engine with the stroke volume of 650 cc was used with four kinds of expansion ratio (geometrical compression ratio) from 10 to 25 and four sets of intake valve closure (I.V.C.) timings from 0 to 110 deg C.A. ABDC. Late-closing has an effect of decreasing the pumping work due to the reduction of intake vacuum, althogh higher expansion ratio increases the friction work due to the average cylinder pressure level. Combining the higher expansion ratio with the late-closing determines the mechanical efficiency on the basis of these two contrastive effects. The indicated thermal efficiency is mostly determined by the expansion ratio and little affected by the nominal compression ratio. The value of the indicated thermal efficiency reaches to 48% at most which is almost comparable with the value of diesel engines. The improvement of both indicated and brake thermal efficiency reaches to 16% which is much higher than ever reported by the authors. A simple thermodynamic calculation could successfully explain the behavior of the indicated thermal efficiency. The brake thermal efficiency could also be improved due to the increase in both mechanical and indicated efficiencies.

Effect of Spark Timing on Performance of a Hydrogen Gasoline Engine

2015 ◽  
Vol 713-715 ◽  
pp. 239-242 ◽  
Author(s):  
Wei Bo Shi ◽  
Xiu Min Yu ◽  
Ping Sun
Keyword(s):  
Gasoline Engine ◽  
Direct Injection ◽  
Engine Performance ◽  
Spark Ignition Engine ◽  
Gasoline Direct Injection ◽  
Hydrogen Energy ◽  
Energy Fraction ◽  
Direct Injection Engine ◽  
Excess Air ◽  
Spark Timing

Hydrogen-gasoline blends is an effective way to improving the performance of spark ignition engine at stoichiometric and lean conditions. Spark timing is one of the important parameters affect the engine performance. This paper investigated the effect of spark timing on performance of a hydrogen-gasoline engine. A four cylinder, gasoline direct injection engine was modified to be a gasoline port injection, hydrogen direct injection engine. The hydrogen energy fraction was set as 0% and 30%. For a specified hydrogen addition, the engine was operated at four excess air ratios of 0.8, 1.0, 1.2 and 1.5. Under the specified excess air ratio condition, the spark timing was varied from 4 to 19°CA before top dead center (BTDC) with an interval of 3°CA. The test result showed that the indicated mean effective pressure (IMEP) climb up and then decline with the increase of spark advance. For hydrogen-gasoline engine, the optimum spark timing for the max IMEP was retarded at a specified excess air ratio. The max thermal efficiency appeared at the optimum spark timing.

Some aspects concerning the combination of downsizing with turbocharging, variable compression ratio, and variable intake valve lift

2007 ◽  
Vol 221 (10) ◽  
pp. 1287-1294 ◽  
Author(s):  
A C Clenci ◽  
G Descombes ◽  
P Podevin ◽  
V Hara
Keyword(s):  
Compression Ratio ◽  
Gasoline Engine ◽  
Control Method ◽  
Operation Time ◽  
Spark Ignition Engine ◽  
Valve Lift ◽  
Boost Pressure ◽  
Intake Valve ◽  
Variable Compression Ratio ◽  
Variable Compression

The inefficient running of the spark ignition engine at part loads due to the load control method but, mostly, their major weighting in the vehicle's operation time justifies the interest in the technical solutions, which act in this particular operating range. These drawbacks encountered at low part loads are even more amplified when considering larger engines. For instance, it is well known that, at the same engine load, a larger engine is more throttled than a smaller engine; therefore the concerns are the higher pumping work, the lower real compression ratio, and the overall mechanical efficiency, which is also lower. One solution is a reduction in the displacement without affecting the power output. This is what is now commonly known as the downsizing technique. The combination of downsizing and uploading an engine has been known for a long time. However, the conversion, in an acceptable way, of this potential to actual practice is very challenging. On the one hand, the degree of the downsizing is related to the boost pressure. In order to cope with the knocking phenomenon, the downsized high-pressure turbocharged gasoline engine requires a lower volumetric compression ratio that limits the efficiency on part loads. Therefore, the degree of the downsizing has been limited and, thus, the possible fuel consumption reduction has not yet been fully achieved. On the other hand, other problems are encountered when considering a downsized turbocharged gasoline engine: insufficient low-end torque, poor starting performance, and turbo lag. In order to solve these problems an effective combination of the downsized turbocharged gasoline engine with additional technologies is needed. Thus, the paper will present a so-called adaptive thermal engine, which has at the same time a variable compression ratio and a variable intake valve lift. It will then be demonstrated that it is highly suitable for turbocharging, thus resulting in a high downsizing factor.

scholarly journals Experimental Investigation of Performance Characteristics of Compression Ignition Engine Fuelled with Punnai Oil Methyl Ester Blended Diesel

2017 ◽  
Vol 60 (1) ◽  
pp. 23-28
Author(s):  
Mathan Raj Vijayaragavan ◽  
Ganapathy Subramanian ◽  
Lalgudi Ramachandran ◽  
Manikandaraja Gurusamy ◽  
Rahul Kumar Tiwari ◽  
...  
Keyword(s):  
Cetane Number ◽  
Load Condition ◽  
Calorific Value ◽  
Mechanical Efficiency ◽  
Performance Characteristics ◽  
Brake Specific Fuel Consumption ◽  
Compression Ignition ◽  
Compression Ignition Engine ◽  
Brake Thermal Efficiency ◽  
Full Load

Biodiesel is a renewable substitute to conventional diesel and offers cleaner performance. Thispaper deals with performance characteristics of four stroke, water cooled Compression Ignition (CI) enginefuelled with four different oils: diesel, diesel-punnai oil biodiesel 10% (B10), diesel-punnai oil biodiesel20% (B20) and diesel-punnai oil biodiesel 30% (B30). The present research, experiments were conductedto study the effect of viscosity, cetane number, flash point, calorific value and density on performancecharacteristics of diesel, Punnai oil biodiesel and its different blends (B10, B20, B30). The experimentalresults of this study showed that the diesel has 2.6% and 4.6% higher brake specific fuel consumption(BSFC) as compared to B10 and B20, respectively at full load, whereas BSFC of diesel was same as B30at higher load. Volumetric efficiency and mechanical efficiency of B10 was 1.2% and 7.5% higher ascompared to diesel at full load condition. Brake Thermal Efficiency (BTE) and indicated thermal efficiencyof B20 was 8.12% and 7% higher as compared to diesel at full load. From this study, it is concluded thatPunnai oil biodiesel could be used as a viable alternative fuel in a single cylinder, four stroke, water cooleddirect injection diesel engine.

scholarly journals Influence of Compression Ratio on Flywheel Dimension for a Naturally Aspirated Spark Ignition Engine: A Numerical Study

2020 ◽  
Vol 3 (2) ◽  
Author(s):  
Aan Yudianto ◽  
Peixuan Li
Keyword(s):  
Compression Ratio ◽  
Numerical Study ◽  
Engine Performance ◽  
Spark Ignition ◽  
Spark Ignition Engine ◽  
Effective Pressure ◽  
Si Engine ◽  
Compression Stroke ◽  
Indicated Mean Effective Pressure ◽  
Proper Design

The proper design of the flywheel undeniably determines in tuning the engine to confirm the better output engine performance. The aim of this study is to mathematically investigate the effect of various values of the compression ratio on some essential parameters to determine the appropriate value for the flywheel dimension. A numerical calculation approach was proposed to eventually determine the dimension of the engine flywheel on a five-cylinder four-stroke Spark Ignition (SI) engine. The various compression ratios of 8.5, 9, 9.5, 10, 10.5, and 11 were selected to perform the calculations. The effects of compression ratio on effective pressure, indicated mean effective pressure (IMEP), dynamic irregularity value of the crankshaft, and the diameter of the flywheel was clearly investigated. The study found that 2.5 increment value of the compression ratio significantly increases the effective pressure of about 41.53% on the starting of the expansion stroke. While at the end of the compression stroke, the rise of effective pressure is about 76.67%, and the changes in dynamic irregularity merely increase by about 1.79%. The same trend applies to the flywheel diameter and width, which increases 2.08% for both.

scholarly journals One-Dimensional Simulation Using Port Water Injection for a Spark Ignition Engine

2018 ◽  
Vol 15 (4) ◽  
pp. 5803-5814 ◽  
Author(s):  
C. H. Ling ◽  
M. A. Abas
Keyword(s):  
Fuel Consumption ◽  
Gasoline Engine ◽  
Nox Reduction ◽  
Water Injection ◽  
Engine Performance ◽  
Simulation Software ◽  
Spark Ignition Engine ◽  
Baseline Model ◽  
One Dimensional ◽  
Model Water

Water injection is a promising solution to reduce fuel consumption while improving the performance of a turbocharged gasoline engine. One-dimensional (1D) engine simulation software, AVL BOOST is rarely used to model water injection. Therefore, this study is aimed to demonstrate the detailed port water injection modelling via AVL BOOST. A four-cylinder turbocharged gasoline engine was developed in AVL BOOST based on the specification of the engine test rig and verified to be used as the baseline model. The port water injection modelling was then added to the baseline model. Water to fuel mass ratios of 0.05, 0.10, 0.15, 0.2 and 0.25 were chosen as the variables to investigate the effect of water injection on the engine performance. The results showed that maximum engine torque and IMEP increased by 10.80% and 8.65%, respectively at 3000 rpm. The water injection also reduced the in-cylinder pressure at the end of the compression stroke, reducing the compression work and improving efficiency. The reduction of combustion temperature also indicates potential for NOx reduction. The lower exhaust temperature can reduce the use of fuel enrichment which consequently reduces the fuel consumption. Conclusively, the water injection model can predict the engine performance parameters accurately.

Investigations of DI CI engine using algal particles contained coconut biodiesel

2019 ◽  
pp. 52-61
Author(s):  
Katam Ganesh Babu ◽  
A. Veeresh Babu ◽  
K. Madhu Murthy
Keyword(s):  
Engine Performance ◽  
Calorific Value ◽  
Emission Characteristics ◽  
Nox Emissions ◽  
Third Generation ◽  
Brake Thermal Efficiency ◽  
Performance And Emission ◽  
Greenhouse Emissions ◽  
Engine Combustion ◽  
Ci Engine

Day to day increasing vehicles usage for human activities is caused to accumulate greenhouse emissions into the environment. The biodiesel is a best alternative fuel to run diesel engines. But its lower Calorific value and higher NOx emissions makes the consumer should compromise with engine performance and emission characteristics. As we know, that the use of additives to improve engine Combustion and emissions are caused to increase the fuel cost due to the higher cost of additives. The biodiesel conversion process of third generation biodiesel is costlier and required technological advancements for qualitative fuel. In the present work, the author used mixed culture micro algal particles in Coconut biodiesel (CCNME+AP) to improve engine characteristics. The Brake Thermal Efficiency (BTE) was enhanced, and the NOx emissions were less due to the absorption of heat in the Combustion chamber, it led to cool combustion phenomena with the Algal particles contained Coconut Biodiesel (CCNME+AP).

An experimental study on fuel energy saving in gasoline engines using GNP as a lubricant additive

2021 ◽  
pp. 146808742110396
Author(s):  
Gurtej Singh ◽  
Mohammad Farooq Wani ◽  
Mohammad Marouf Wani
Keyword(s):  
Piston Ring ◽  
Energy Savings ◽  
Gasoline Engine ◽  
Engine Performance ◽  
Mechanical Efficiency ◽  
Lubricant Additive ◽  
Lubricating Oil ◽  
Engine Torque ◽  
Gasoline Engines ◽  
Improved Performance

This study concentrates on enhancing the performance of the gasoline engine through nano-lubrication. The effect of Graphene nano-platelets (GNP) as lubricant additives in SAE 15W40 oil on the fuel energy consumption and piston ring wear is investigated. GNP-filled lubricating oil boosted the brake strength, engine torque, and mechanical efficiency, whereas the gasoline engine’s brake specific fuel consumption (BSFC) decreased by 5.3%–6.5% due to a 1.7%–3.46% improvement in engine mechanical efficiency. Further, emission results showed that the GNP-filled lubricating oil reduced the emissions of the engine by approximately 3%–6% as compared to the virgin lubricating oil. Furthermore, the piston ring wear was found to reduce by using GNP-filled nano-lubricant. The characterization of the worn piston ring surfaces showed that the tribo-film formed on wear tracks resulted in the improved performance of the engine thereby reducing abrasive wear and surface roughness. From these studies, an attempt has been made to co-relate engine performance characteristics with tribological perception to contribute in the direction of energy savings and fuel economy.

scholarly journals The Operating Features of a Stoichiometric, Ammonia and Gasoline Dual Fueled Spark Ignition Engine

2006 ◽  
Author(s):  
Shawn M. Grannell ◽  
Dennis N. Assanis ◽  
Stanislav V. Bohac ◽  
Donald E. Gillespie
Keyword(s):  
Compression Ratio ◽  
Thermal Efficiency ◽  
Maximum Load ◽  
Spark Ignition ◽  
Spark Ignition Engine ◽  
Gaseous Ammonia ◽  
Spark Ignition Engines ◽  
Stoichiometric Mixture ◽  
Brake Thermal Efficiency ◽  
Practical Operation

An overall stoichiometric mixture of air, gaseous ammonia and gasoline was metered into a single cylinder, variable compression ratio, supercharged CFR engine at varying ratios of gasoline to ammonia. The engine was operated such that the combustion was knock-free with minimal roughness for all loads ranging from idle up to a maximum load in the supercharge regime. For a given load, speed, and compression ratio there was a range of ratios of gasoline to ammonia for which knock-free, smooth firing was obtained. This range was investigated at its roughness limit and also at its knock limit. If too much ammonia was used, then the engine fired with an excessive roughness. If too much gasoline was used, then knock-free combustion could not be obtained while the maximum brake torque spark advance was maintained. Stoichiometric operation on gasoline alone was also investigated, for comparison. It was found that a significant fraction of the gasoline used in spark ignition engines could be replaced with ammonia. Operation on mostly gasoline was required near idle. However, mostly ammonia could be used at high load. Operation on ammonia alone was possible at some of the supercharged load points. Generally, the use of ammonia or ammonia with gasoline allowed knock-free operation at higher compression ratios and higher loads than could be obtained with the use of gasoline alone. The use of ammonia/gasoline allowed practical operation at a compression ratio of 12:1 whereas the limit for gasoline alone was 9:1. When running on ammonia/gasoline the engine could be operated at brake mean effective pressures that were more than 50% higher than those achieved with the use of gasoline alone. The maximum brake thermal efficiency achieved with the use of ammonia/gasoline was 32.0% at 10:1 compression ratio and BMEP = 1025 kPa. The maximum brake thermal efficiency possible for gasoline was 24.6% at 9:1 and BMEP = 570 kPa.

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