Effect of Injection Timing, Premixed Equivalence Ratio and EGR on Combustion Characteristics of an HCCI-DI Combustion Engine Using In-Cylinder Dual Injection Strategy

The performance of diesel engine highly depends on atomization, vaporization and mixing of fuel with air. These factors are strongly influenced by various parameters e.g. injection pressure, injection timing, compression ratio, equivalence ratio, cylinder geometry, in cylinder air motion etc. In this study, a diesel engine has been investigated by employing a commercial CFD software (ANSYS Forte, version 18.1) especially developed for internal combustion engines (ICE) modeling; focusing primarily on the effects of equivalence ratio and compression ratio on combustion and emission characteristics. RNG k-ε model was employed as the turbulence model for analyzing the physical phenomena involved in the change of kinetic energy. In order to reduce the computational cost and time, a sector mesh of 45o angle with periodic boundary conditions applied at the periodic faces of the sector, is considered instead of using the whole engine geometry. Simulations are performed for a range of equivalence ratio varying from 0.6 to 1.2 and for three compression ratios namely, 15:1, 18:1 and 21:1. Results show that, improvement in combustion characteristics with higher compression ratio could be achieved for both lean and rich mixtures. Peak in-cylinder pressure and peak heat release nearer to TDC are achieved for compression ratio of 18:1 that could results in more engine torque. For compression ratio beyond 16:1, effects of fuel concentration on ignition delay is more pronounced. At lower compression ratio, in-cylinder temperature is not sufficiently high for atomization, vaporization, mixing of fuel with air, and preflame reactions to occur immediately after the fuel injection. NOx emission in diesel engine increases due to higher pressure and temperature inside the cylinder associated with relatively higher compression ratio. Rich mixture leads to more CO and unburnt hydrocarbon emission compared to lean mixture as result of incomplete combustion. Engine operation with too high compression ratio is detrimental as emission is a major concern.

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Effect of main injection timing for controlling the combustion phasing of a homogeneous charge compression ignition engine using a new dual injection strategy

Energy Conversion and Management ◽

10.1016/j.enconman.2015.02.018 ◽

2015 ◽

Vol 95 ◽

pp. 248-258 ◽

Cited By ~ 16

Author(s):

Pranab Das ◽

P.M.V. Subbarao ◽

J.P. Subrahmanyam

Keyword(s):

Homogeneous Charge Compression Ignition ◽

Injection Timing ◽

Compression Ignition ◽

Compression Ignition Engine ◽

Injection Strategy ◽

Dual Injection ◽

Main Injection ◽

Homogeneous Charge

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Numerical study on the effects of intake charge on oxy-fuel combustion in a dual-injection spark ignition engine at economical oxygen-fuel ratios

International Journal of Engine Research ◽

10.1177/14680874211022292 ◽

2021 ◽

pp. 146808742110222

Author(s):

Xiang Li ◽

Yiqiang Pei ◽

Zhijun Peng ◽

Tahmina Ajmal ◽

Khaqan-Jim Rana ◽

...

Keyword(s):

Combustion Engine ◽

Numerical Study ◽

Carbon Capture And Storage ◽

Spark Ignition ◽

Fuel Combustion ◽

Spark Ignition Engine ◽

Gasoline Direct Injection ◽

Brake Mean Effective Pressure ◽

Dual Injection ◽

Injection Strategies

In order to decrease Carbon Dioxide (CO2) emissions, Oxy-Fuel Combustion (OFC) technology with Carbon Capture and Storage (CCS) is being developed in Internal Combustion Engine (ICE). In this article, a numerical study about the effects of intake charge on OFC was conducted in a dual-injection. Spark Ignition (SI) engine, with Gasoline Direct Injection (GDI), Port Fuel Injection (PFI) and P-G (50% PFI and 50% GDI) three injection strategies. The results show that under OFC with fixed Oxygen Mass Fraction (OMF) and intake temperature, the maximum Brake Mean Effective Pressure (BMEP) is each 5.671, 5.649 and 5.646 bar for GDI, P-G and PFI strategy, which leads to a considerable decrease compared to Conventional Air Combustion (CAC). [Formula: see text], [Formula: see text] and [Formula: see text] of PFI are the lowest among three injection strategies. With intake temperature increases from 298 to 378 K, the reduction of BMEP can be up to 12.68%, 12.92% and 12.75% for GDI, P-G and PFI, respectively. Meantime, there is an increase of about 3% in Brake Specific Fuel Consumption (BSFC) and Brake Specific Oxygen Consumption (BSOC). Increasing OMF can improve the performance of BMEP and BSFC, and the trend is more apparent under GDI strategy. Besides, an increasing tendency can be observed for cylinder pressure and in-cylinder temperature under all injection strategies with the increase of OMF.

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Simulation of HCCI Combustion Characteristics for Low RON Gasoline Surrogate Fuels

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.694.54 ◽

2014 ◽

Vol 694 ◽

pp. 54-58

Author(s):

Ling Zhe Zhang ◽

Ya Kun Sun ◽

Su Li ◽

Qing Ping Zheng

Keyword(s):

Equivalence Ratio ◽

Chemical Kinetic ◽

Combustion Characteristics ◽

Material Strength ◽

Inlet Temperature ◽

Compression Ignition Engine ◽

Chemical Kinetic Model ◽

Hcci Engine ◽

Surrogate Fuels ◽

Inlet Conditions

A reduced chemical kinetic model (103species and 468 reactions) for new low-RON(research octane number) gasoline surrogate fuels has been proposed. Simulations explored for ignition delay time have been compared with experimental data in shock tubes at pressure of 10atm-55 atm and temperatue of 600-1400 K (fuel/air equivalence ratio=0.5,1.0,2.0 and EGR rate=0, 20%). The simulation data presented 15% enlargement compared with experiments showed applicability of the new kinetic mode in this work. A combustion simulation model has been build for HCCI(homogeneous charge compression ignition) engine with Chemkin-pro. The effects of different air inlet temperature, inlet pressure, engine speed and the fuel air equivalence ratio on the combustion characteristics of the fuel were researched. The results indicated the combustion in an HCCI engine worked sufficiently with lean mixtures and low speed. Meanwhile the material strength could be influenced when the inlet conditions changed. This helps to promote the low-RON gasoline surrogate fuel application in the HCCI engine.

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Effect of Injection Timing on Combustion Characteristics of a DI Diesel Engine Fuelled with Pistacia chinensis Bunge Seed Biodiesel

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.614-615.337 ◽

2012 ◽

Vol 614-615 ◽

pp. 337-342

Author(s):

Li Luo ◽

Bin Xu ◽

Zhi Hao Ma ◽

Jian Wu ◽

Ming Li

Keyword(s):

Combustion Temperature ◽

Fuel Injection ◽

Direct Injection ◽

Combustion Characteristics ◽

Injection Timing ◽

Brake Specific Fuel Consumption ◽

Cylinder Pressure ◽

Combustion Duration ◽

Di Diesel Engine ◽

Maximum Combustion Temperature

In this study, the effect of injection timing on combustion characteristics of a direct injection, electronically controlled, high pressure, common rail, turbocharged and intercooled engine fuelled with different pistacia chinensis bunge seed biodiesel/diesel blends has been experimentally investigated. The results indicated that brake specific fuel consumption reduces with the increasing of fuel injection advance angle and enhances with the increasing of biodiesel content in the blends. The peak of cylinder pressure and maximum combustion temperature increase evidently with the increment of fuel injection advance angle. However, the combustion of biodiesel blends starts earlier than diesel at the same fuel injection advance angle. At both conditions, the combustion duration and the peak of heat release rate are insensitive to the changing of injection timing.

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Engine Performance of a Gardener Compression Ignition Engine using Rapeseed Methyl Esther

FUOYE Journal of Engineering and Technology ◽

10.46792/fuoyejet.v4i2.325 ◽

2019 ◽

Vol 4 (2) ◽

Author(s):

Hamisu A Dandajeh ◽

Talib O Ahmadu

Keyword(s):

Mass Flow Rate ◽

Mass Flow ◽

Flow Rate ◽

Equivalence Ratio ◽

Engine Speed ◽

Engine Performance ◽

Combustion Characteristics ◽

Compression Ignition ◽

Compression Ignition Engine ◽

Air Mass

This paper presents an experimental investigation on the influence of engine speed on the combustion characteristics of a Gardener compression ignition engine fueled with rapeseed methyl esther (RME). The engine has a maximum power of 14.4 kW and maximum speed of 1500 rpm. The experiment was carried out at speeds of 750 and 1250 rpm under loads of 4, 8, 12, 16 and 18 kg. Variations of cylinder pressure with crank angle degrees and cylinder volume have been examined. It was found that RME demonstrated short ignition delay primarily due to its high cetane number and leaner fuel properties (equivalence ratio (φ) = 0.22 at 4kg). An increase in thermal efficiency but decrease in volumetric efficiency was recorded due to increased brake loads. Variations in fuel mass flow rate, air mass flow rate, exhaust gas temperatures and equivalence ratio with respect to brake mean effective pressure at engine speeds of 750 and 1250 rpm were also demonstrated in this paper. Higher engine speed of 1250 rpm resulted in higher fuel and air mass flow rates, exhaust temperature, brake power and equivalent ratio but lower volumetric efficiency. Keywords— combustion characteristics, engine performance, engine speed, rapeseed methyl Esther

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Spray and Combustion Characteristics of Biodiesel∕Diesel Blended Fuel in a Direct Injection Common-Rail Diesel Engine

Journal of Engineering for Gas Turbines and Power ◽

10.1115/1.2835354 ◽

2008 ◽

Vol 130 (3) ◽

Cited By ~ 51

Author(s):

Hyun Kyu Suh ◽

Hyun Gu Roh ◽

Chang Sik Lee

Keyword(s):

Diesel Engine ◽

Diesel Fuel ◽

Direct Injection ◽

Injection Rate ◽

Combustion Characteristics ◽

Biodiesel Fuel ◽

Injection Timing ◽

Pilot Injection ◽

Blended Fuel ◽

Conventional Diesel Fuel

The aim of this work is to investigate the effect of the blending ratio and pilot injection on the spray and combustion characteristics of biodiesel fuel and compare these factors with those of diesel fuel in a direct injection common-rail diesel engine. In order to study the factors influencing the spray and combustion characteristics of biodiesel fuel, experiments involving exhaust emissions and engine performance were conducted at various biodiesel blending ratios and injection conditions for engine operating conditions. The macroscopic and microscopic spray characteristics of biodiesel fuel, such as injection rate, split injection effect, spray tip penetration, droplet diameter, and axial velocity distribution, were compared with the results from conventional diesel fuel. For biodiesel blended fuel, it was revealed that a higher injection pressure is needed to achieve the same injection rate at a higher blending ratio. The spray tip penetration of biodiesel fuel was similar to that of diesel. The atomization characteristics of biodiesel show that it has higher Sauter mean diameter and lower spray velocity than conventional diesel fuel due to high viscosity and surface tension. The peak combustion pressures of diesel and blending fuel increased with advanced injection timing and the combustion pressure of biodiesel fuel is higher than that of diesel fuel. As the pilot injection timing is retarded to 15deg of BTDC that is closed by the top dead center, the dissimilarities of diesel and blending fuels combustion pressure are reduced. It was found that the pilot injection enhanced the deteriorated spray and combustion characteristics of biodiesel fuel caused by different physical properties of the fuel.

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Analysis of Biodiesel Spray Combustion in Internal-Combustion Engine using Multidimensional Models

International Journal of Vehicle Structures and Systems ◽

10.4273/ijvss.13.4.07 ◽

2021 ◽

Vol 13 (4) ◽

Author(s):

Qiuyu Zheng ◽

Xu Wang ◽

Yi Liu ◽

Feng Jiang ◽

Tianqi Liu

Keyword(s):

Internal Combustion Engine ◽

Combustion Engine ◽

Internal Combustion ◽

Phase Control ◽

Combustion Characteristics ◽

Liquid Fuels ◽

Spray Combustion ◽

Dimensional Model ◽

Fuel Temperature ◽

Ic Engine

With the rapid scale expansion of the first generation of bio-liquid fuels, its impact on the prices of agricultural products, food security and the environment has begun to emerge and attracted extensive attention from governments and academia. A new multi-dimensional model of biodiesel spray combustion in an internal combustion (IC) engine is designed. Firstly, the BP neural network mining model is used to extract the spray combustion data of the IC engine. Then, based on the combustion data of biodiesel load in an internal combustion engine, burning rate and heat release, the principle of spray combustion of biodiesel is analyzed. Finally, from the two aspects of gas-phase control and liquid phase control, a multi-dimensional model of biodiesel spray combustion in IC engine is established and the spray combustion characteristics of biodiesel in IC engine are analyzed. The research results show that the model can effectively analyze the effect of load and fuel temperature on the spray combustion characteristics of biodiesel and the results of the model are almost the same as the actual data and the calculation accuracy is high. It is an effective method for studying the spray combustion characteristics of biodiesel.

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