scholarly journals Effects of intake air temperature on homogenous charge compression ignition combustion and emissions with gasoline and n-heptane

2015 ◽  
Vol 19 (6) ◽  
pp. 1897-1906 ◽  
Author(s):  
Jianyong Zhang ◽  
Zhongzhao Li ◽  
Kaiqiang Zhang ◽  
Xingcai Lv ◽  
Zhen Huang
Keyword(s):  
Air Temperature ◽  
Fuel Injection ◽  
Combustion Stability ◽  
Dual Fuel ◽  
Maximum Pressure ◽  
Heat Management ◽  
Hcci Combustion ◽  
Combustion Duration ◽  
Homogenous Charge Compression Ignition ◽  
Compression Ignition Combustion

In a port fuel injection engine, Optimized kinetic process (OKP) technology is implemented to realize HCCI combustion with dual-fuel injection. The effects of intake air temperature on HCCI combustion and emissions are investigated. The results show that dual-fuel control prolongs HCCI combustion duration and improves combustion stability. Dual-fuel HCCI combustion needs lower intake air temperature than gasoline HCCI combustion, which reduces the requirements on heat management system. As intake air temperature decreases, air charge increases and maximum pressure rising rate decreases. When intake air temperature is about 55?C, HCCI combustion becomes worse and misfire happens. In fixed dual fuel content condition, HC and CO emission decreases as intake air temperature increases. The combination of dual-fuel injection and intake air temperature control can expand operation range of HCCI combustion.

scholarly journals Comparative Analysis of Combustion Stability of Diesel/Ethanol Utilization by Blend and Dual Fuel

Processes ◽  
2019 ◽  
Vol 7 (12) ◽  
pp. 946 ◽  
Author(s):  
Wojciech Tutak ◽  
Arkadiusz Jamrozik
Keyword(s):  
Diesel Fuel ◽  
Fuel Injection ◽  
Combustion Process ◽  
Combustion Stability ◽  
Dual Fuel ◽  
Maximum Pressure ◽  
Compression Ignition Engine ◽  
Energy Fraction ◽  
Pure Ethanol ◽  
Advantages And Disadvantages

The aim of the work is a comparison of two combustion systems of fuels with different reactivity. The first is combustion of the fuel mixture and the second is combustion in a dual-fuel engine. Diesel fuel was burned with pure ethanol. Both methods of co-firing fuels have both advantages and disadvantages. Attention was paid to the combustion stability aspect determined by COVIMEP as well as the probability density function of IMEP. It was analyzed also the spread of the maximum pressure value, the angle of the position of maximum pressure. The influence of ethanol on ignition delay time spread and end of combustion process was evaluated. The experimental investigation was conducted on 1-cylinder air cooled compression ignition engine. The test engine operated with constant rpm equal to 1500 rpm and constant angle of start of diesel fuel injection. The engine was operated with ethanol up to 50% of its energy fraction.

scholarly journals An experiment study of homogeneous charge compression ignition combustion and emission in a gasoline engine

2014 ◽  
Vol 18 (1) ◽  
pp. 295-306
Author(s):  
Jianyong Zhang ◽  
Zhongzhao Li ◽  
Kaiqiang Zhang ◽  
Lei Zhu ◽  
Zhen Huang
Keyword(s):  
Air Temperature ◽  
Gasoline Engine ◽  
Fuel Injection ◽  
Air Pressure ◽  
Compression Ignition ◽  
Effective Pressure ◽  
Indicated Mean Effective Pressure ◽  
Hcci Combustion ◽  
Combustion Duration ◽  
Combustion Phase

Homogenous charge compression ignition (HCCI) technology has exhibited high potential to reduce fuel consumption and NOx emissions over normal spark ignition engines significantly. Optimized kinetic process (OKP) technology is implemented to realize HCCI combustion in a port fuel injection gasoline engine. The combustion and emission characteristics are investigated with variation of intake air temperature, exhaust gas recirculation (EGR) rate and intake air pressure. The results show that intake air temperature has great influence on HCCI combustion characteristic. Increased intake air temperature results in advance combustion phase, shorten combustion duration, and lower indicated mean effective pressure (IMEP). Increased EGR rate retards combustion start phase and prolongs combustion duration, while maximum pressure rising rate and NOx emission are reduced with increase of EGR rate. In the condition with constant fuel flow quantity, increased air pressure leads to retarded combustion phase and lower pressure rising rate, which will reduce the engine knocking tendency. In the condition with constant air fuel ratio condition, fuel injection quantity increases as intake air pressure increases, which lead to high heat release rate and high emission level. The optimal intake air temperature varies in different operating area, which can be tuned from ambient temperature to 220? by heat management system. The combination of EGR and air boost technology could expand operating area of HCCI engine, which improve indicated mean effective pressure from maximum 510kPa to 720kPa.

scholarly journals Quantitative analysis of combustion process of marine dual fuel engine under the framework of iconology

2021 ◽  
Vol 9 (4B) ◽  
Author(s):  
Hongliang Yu ◽  
◽  
Weiwei Wang ◽  
Shulin Duan ◽  
Peiting Sun ◽  
...  
Keyword(s):  
Combustion Process ◽  
Image Feature ◽  
Combustion Stability ◽  
Dual Fuel ◽  
Flame Velocity ◽  
Combustion Duration ◽  
Engine Cylinder ◽  
Characteristic Values ◽  
Feature Values ◽  
Logical Mapping

The methane (CH4) burning interruption factor and the characteristic values characterizing the flame combustion state in the engine cylinder were defined. The logical mapping relationship between image feature values and combustion conditions in the framework of iconology was proposed. Results show that there are two periods of combustion instability and combustion stability during the combustion of dual fuel. The high temperature region with a cylinder temperature greater than 1800K is the largest at 17°CA after top dead center (TDC), accounting for 73.25% of the combustion chamber area. During the flame propagation, the radial flame velocity and the axial flame velocity are “unimodal” and “wavy,” respectively. During the combustion process, the CH4 burning interruption factor first increased and then decreased. The combustion duration in dual fuel mode is 21.25°CA, which is 15.5°CA shorter than the combustion duration in pure diesel mode.

scholarly journals Combustion stability of dual fuel engine powered by diesel-ethanol fuels

2019 ◽  
Vol 178 (3) ◽  
pp. 155-161
Author(s):  
Łukasz NOWAK ◽  
Wojciech TUTAK
Keyword(s):  
Diesel Fuel ◽  
Combustion Process ◽  
Combustion Stability ◽  
Dual Fuel ◽  
Probability Density Distribution ◽  
Maximum Pressure ◽  
Operational Parameters ◽  
Compression Ignition Engine ◽  
Energy Fraction ◽  
The Stability

The paper presents result of combustion stability assessment of dual fuel engine. The authors analyzed results of co-combustion of diesel fuel with alcohol in terms of combustion stability. The comparative analysis of both the operational parameters of the engine and the IMEP, as the parameters determining the stability of the combustion process, were carried out. It was analyzed, among others values of the COVIMEP coefficient, the spread of the maximum pressure value, the angle of the position of maximum pressure and the probability density distribution of the IMEP. The experimental investigation was conducted on 1-cylinder air cooled compression ignition engine. The test engine operated with constant rpm equal to 1500 rpm and constant angle of start of diesel fuel injection. The engine was operat-ed with ethanol up to 50% of its energy fraction. The influence of ethanol on ignition delay time spread and end of combustion process was evaluated. It turns out that the share of ethanol does not adversely affect the stability of ignition..

Effects of Fuel Octane Number on Homogeneous Charge Compression Ignition (HCCI) Combustion with Rapid Compression Machine

2012 ◽  
Vol 455-456 ◽  
pp. 339-343
Author(s):  
You Kun Wang ◽  
Peng Cheng ◽  
Yun Kai Wang ◽  
Hua Li ◽  
Ying Nan Guo
Keyword(s):  
Octane Number ◽  
Homogeneous Charge Compression Ignition ◽  
Maximum Pressure ◽  
Compression Ignition ◽  
Rapid Compression Machine ◽  
Hcci Combustion ◽  
Combustion Duration ◽  
Rapid Compression ◽  
Start Of Combustion ◽  
Homogeneous Charge

The effects of fuel octane number (RON) on homogeneous charge compression ignition (HCCI) combustion were studied under different combustion boundary conditions on a rapid compression machine. The results show that the maximum pressure raise rate and maximum combustion temperature decreased as the RON increased while the start of combustion is delayed and the combustion duration is shortened at the same time.

Implementation Challenges and Solutions for Homogenous Charge Compression Ignition Combustion in Diesel Engines

2014 ◽  
Author(s):  
Usman Asad ◽  
Ming Zheng ◽  
David Ting ◽  
Jimi Tjong
Keyword(s):  
High Pressure ◽  
Diesel Engines ◽  
Performance Metrics ◽  
Pressure Rise ◽  
Engine Performance ◽  
Injection Pressure ◽  
Combustion Stability ◽  
Compression Ignition ◽  
Hcci Combustion ◽  
Homogenous Charge Compression Ignition

Homogenous charge compression ignition (HCCI) combustion in diesel engines can provide for cleaner operation with ultra-low NOx and soot emissions. While HCCI combustion has generated significant attention in the last decade, however, to date, it has seen very limited application in production diesel engines. HCCI combustion is typically characterized by earlier than top-dead-center (pre-TDC) phasing, very high pressure rise rates, short combustion durations and minimal control over the timing of the combustion event. To offset the high reactivity of the diesel fuel, large amounts of EGR (30 to 60%) are usually applied to postpone the initiation of combustion, shift the combustion towards TDC and alleviate to some extent, the high pressure rise rates and the reduced energy efficiency. In this work, a detailed analysis of HCCI combustion has been carried out on a high-compression ratio, single-cylinder diesel engine. The effects of intake boost, EGR quantity/temperature, engine speed, injection scheduling and injection pressure on the operability limits have been empirically determined and correlated with the combustion stability, emissions and performance metrics. The empirical investigation is extended to assess the suitability of common alternate fuels (n-butanol, gasoline and ethanol) for HCCI combustion. On the basis of the analysis, the significant challenges affecting the real-world application of HCCI are identified, their effects on the engine performance quantified and possible solutions to overcome these challenges explored through both theoretical and empirical investigations. This paper intends to provide a comprehensive summary of the implementation issues affecting HCCI combustion in diesel engines.

Partially Premixed Compression Ignition of Fischer Tropsch Synthetic Paraffinic Kerosene (S8) With PFI of N-Butanol

2017 ◽  
Author(s):  
Valentin Soloiu ◽  
Remi Gaubert ◽  
Jose Moncada ◽  
Spencer Harp ◽  
Kyle Flowers ◽  
...  
Keyword(s):  
Low Temperature ◽  
Fuel Injection ◽  
High Reactivity ◽  
Fuel Combustion ◽  
Dual Fuel ◽  
Compression Ignition ◽  
Ignition Timing ◽  
Fischer Tropsch ◽  
Combustion Duration ◽  
Dual Fuel Combustion

The combustion in an experimental medium duty direct injected engine was investigated in a dual mode process known as partially premixed compression ignition (PPCI). Both a common rail fuel injection system and port fuel injection (PFI) system have been custom designed and developed for the experimental single cylinder engine in order to research the combustion and emissions characteristics of Fischer Tropsch synthetic paraffinic kerosene (S8) with PFI of n-butanol in a low temperature combustion mode (LTC). Baseline results in single fuel (ULSD) combustion were compared to dual fuel strategies coupling both the low and high reactivity fuels. The low reactivity fuel, n-butanol, was port fuel injected in the intake manifold at a constant 30% fuel mass and direct injection of a high reactivity fuel initiated the combustion. The high reactivity fuels are ULSD and a gas to liquid fuel (GTL/S8). Research has been conducted at a constant speed of 1500 RPM at swept experimental engine loads from 3.8 bar to 5.8 bar indicated mean effective pressure (IMEP). Boost pressure and exhaust gas recirculation (EGR) were added at constant levels of 3 psi and 30% respectively. Dual fuel combustion with GTL advanced ignition timing due to the high auto ignition quality and volatility of the fuel. Low temperature heat release (LTHR) was also experienced for each dual-fuel injection strategy prior to the injection of the high reactivity fuel. Peak in-cylinder gas temperatures were similar for each fueling strategy, maintaining peak temperatures below 1400°C. Combustion duration increased slightly in ULSD-PPCI compared to single fuel combustion due to the low reactivity of n-butanol and was further extended with GTL-PPCI from early ignition timing and less premixing. The effect of the combustion duration and ignition delay increased soot levels for dual fuel GTL compared to dual fuel ULSD at 5.8 bar IMEP where the combustion duration is the longest. NOx levels were lowest for GTL-PPCI at each load, with up to a 70% reduction compared to ULSD-PPCI. Combustion efficiencies were also reduced for dual fuel combustion, however the atomization quality of GTL compared to ULSD increased combustion efficiency to reach that of single fuel combustion at 5.8 bar IMEP.

Experimental Research of HCCI Combustion Based on Late Exhaust Duct EGR Strategy

2015 ◽  
Vol 713-715 ◽  
pp. 327-330
Author(s):  
Yin Han Gao ◽  
Yu Chao Jiang ◽  
Peng Cheng ◽  
Jun Cheng Chi ◽  
You Kun Wang
Keyword(s):  
Pressure Rise ◽  
Valve Train ◽  
Maximum Pressure ◽  
Hcci Combustion ◽  
Combustion Duration ◽  
Rise Rate ◽  
Exhaust Duct ◽  
Variable Valve Train ◽  
Test Engine ◽  
Variable Valve

Late exhaust duct EGR strategy is one of internal EGR strategies to realize HCCI combustion. Based on a single-cylinder test engine system equipped with an electronic controlled hydraulic variable valve train system, the effects of valve phases in this strategy were studied. The results show that at engine speed 1000r/min, equivalent air-fuel ratio λ= 1, when the IVO phase is put off, EGR ratio increases gradually, CA10 and CA50 are postponed and combustion duration becomes longer. At the same time, peak pressure and maximum pressure rise rate have a tendency to descend. When the SEVO phase is postponed, the parameters of the test engine will also be affected. However, when the phase is postponed above the critical point, the parameters have a backward trend. The property of HCCI combustion is not sensitive to SEVO phase.

Experimental Investigation of Direct Fuel Injection into Low-Oxygen Recompression Interval in a Homogenous Charge Compression Ignition Engine

2021 ◽  
pp. 1-25
Author(s):  
Ratnak Sok ◽  
Jin Kusaka
Keyword(s):  
Thermal Efficiency ◽  
Fuel Injection ◽  
Pressure Rise ◽  
Operating Conditions ◽  
Combustion Noise ◽  
Maximum Pressure ◽  
Compression Ignition ◽  
Compression Ignition Engine ◽  
Single Digit ◽  
Homogenous Charge Compression Ignition

Abstract This work analyzed measured data from a single-cylinder engine operated under gasoline direction injection homogenous charge compression ignition (GDI-HCCI) mode. The experiments were conducted at a 0.95 equivalence ratio (φ) under 0.5 MPa indicated mean effective pressure and 1500RPM. A side-mounted injector delivered primary reference fuel (octane number 90) into the combustion chamber during negative valve overlap (NVO). Advanced combustion phase CA50 were observed as a function of the start of injection (SOI) timings. Under φ=0.95, peak NVO in-cylinder pressures were lower than motoring for single and split injections, emphasizing that NVO reactions were endothermic. Zero-dimensional kinetics calculations showed classical reformate species (C3H6, C2H4, CH4) from the NVO rich mixture increased almost linearly due to SOI timings, while H2 and CO were typically low. These kinetically reformed species shortened predicted ignition delays. This work also analyzed the effects of intake pressure and single versus double pulses injections on CA50, burn duration, peak cylinder pressure, combustion noise, thermal efficiency, and emissions. Advanced SOI (single-injection) generated excessive combustion noise metrics over constraint limits, but the double-pulse injection could significantly reduce the metrics (Ringing Intensity ≤ 5 MW/m2, Maximum Pressure Rise Rate = 0.6 MPa/CA) and NOx emission. The engine's net indicated thermal efficiency reached 41% under GDI-HCCI mode against 36% under SI mode for the same operating conditions. Under GDI-HCCI mode and without spark-ignition, late fuel injection in the intake stroke could reduce NOx to a single digit.

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