EGR and Intake Charge Temperature Effects on Dual-Fuel HCCI Combustion and Emissions Characteristics

In the present study a chamfered piston crown design was used in order to reduce unburned hydrocarbon (UHC) emissions from the ring-pack crevice. Compared to the conventional piston design, the chamfered piston showed 17%∼41% reduction in the crevice-borne UHC emissions in homogeneous charge compression ignition (HCCI) combustion. Through parametric sweeps 6 mm was identified to be a suitable chamfer size and the mechanism of the UHC reduction was revealed. Based on the findings in this study, the chamfered piston design was also tested in dual-fuel reactivity controlled compression ignition (RCCI) combustion. In the tested RCCI case using the chamfered piston the UHC and CO emissions were reduced by 79% and 36%, respectively, achieving 99.5% combustion efficiency. This also improved gross indicated thermal efficiency from 51.1% to 51.8% in a 9 bar IMEP RCCI combustion case.

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

Thermal Science ◽

10.2298/tsci140524174z ◽

2015 ◽

Vol 19 (6) ◽

pp. 1897-1906 ◽

Cited By ~ 2

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.

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G0710105 Dual fuel HCCI combustion using two fuels with different oxidation characteristics : Ignition behavior of iso-Octane as a main fuel

The Proceedings of Mechanical Engineering Congress Japan ◽

10.1299/jsmemecj.2014._g0710105- ◽

2014 ◽

Vol 2014 (0) ◽

pp. _G0710105--_G0710105-

Author(s):

Kunitoshi KANNO ◽

Eri OKAWA ◽

Toru MAEZIMA ◽

Kotaro TANAKA ◽

Mitsuru KONNO

Keyword(s):

Dual Fuel ◽

Hcci Combustion ◽

Oxidation Characteristics

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Investigation of Running HCCI With Dual-Fuel in a Small Scale Engine

ASME 2010 Internal Combustion Engine Division Fall Technical Conference ◽

10.1115/icef2010-35062 ◽

2010 ◽

Author(s):

Yuh-Yih Wu ◽

Hsien-Chi Tsai ◽

Ta-Chuan Liu

Keyword(s):

Pressure Rise ◽

Small Scale ◽

Dual Fuel ◽

Gas Temperature ◽

Si Engine ◽

Average Percentage ◽

Indicated Mean Effective Pressure ◽

Hcci Combustion ◽

Gasoline Additive ◽

Engine Power

Homogeneous charge compression ignition (HCCI) is a well-known technology that reduces the fuel consumption and exhaust emissions. This work implemented HCCI on a 150cc spark-ignition (SI) engine. The compression ratio of target engine was changed from 10.5 to 12.4 to enhance the compression temperature. In addition, a commercialized low-pressure injector was installed near the intake port for supplying fuel for HCCI operation. After the analysis of in-cylinder gas temperature, the dual fuel, with gasoline for the additive fuel and kerosene as the main fuel, was investigated in the small scale target engine. Experiments were executed through various excess air ratios, different gasoline additive ratios and then extension of engine load. Two-stage heat release, which provides energy to heat up the mixture during the compression stroke, was observed from HCCI combustion with kerosene fuel. The maximum rate of pressure rise (MRPR) could be reduced by increasing gasoline additive ratio of dual fuel without deteriorating the engine power output. By using the dual fuel method, the engine indicated mean effective pressure could be improved by a maximum percentage 23.9% and an average percentage 17.6% from just using kerosene fuel under the knocking limitation of MRPR equals to 4 bar/deg.

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Design and Calibration Strategies for Improving HCCI Combustion in Dual-Fuel Diesel–Methane Engines

Energy, Environment, and Sustainability - Natural Gas Engines ◽

10.1007/978-981-13-3307-1_10 ◽

2018 ◽

pp. 267-296

Author(s):

A. P. Carlucci ◽

A. Ficarella ◽

D. Laforgia ◽

L. Strafella

Keyword(s):

Dual Fuel ◽

Hcci Combustion

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Investigation of Auto-Ignition of Heptane-CNG Mixture in HCCI Engine

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.695.468 ◽

2014 ◽

Vol 695 ◽

pp. 468-472

Author(s):

Firmansyah ◽

A. Rashid A. Aziz

Keyword(s):

Combustion Process ◽

Dual Fuel ◽

Fuel Composition ◽

Compression Ignition ◽

Combustion System ◽

Compressed Natural Gas ◽

Hcci Combustion ◽

Auto Ignition ◽

Constant Volume Chamber ◽

Ignition And Combustion

Homogeneous Charge Compression Ignition (HCCI) operating principals have been widely investigated yet the uncontrollable combustion of HCCI is the major obstacle in its development. This paper is trying to increase the understanding on the auto-ignition and combustion process of several fuels to be applied in HCCI combustion system. This paper investigates variation of fuel composition between heptane and compressed natural gas (CNG) with the composition ranges from 10-100% heptane/CNG. The investigation was done in a constant volume chamber with elevated temperature (800°C). Three lambdas were tested for each fuel, namely 0.8, 1, 1.2 and 2. From the results, it is found that the mixture composition highly affects the output of the combustion of dual fuel where CNG is able to suppress heptane combustion at CNG percentage more than 40%. Furthermore, homogeneity level highly determines the types of combustion produced by the mixture, distributed or propagation flame.

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