The Combustion Characteristics of n-Heptane Fueled HCCI Engine Operation With Gaseous Fuels Admission

2006 ◽  
Author(s):  
C. Liu ◽  
G. A. Karim ◽  
A. Sohrabi ◽  
F. Xiao
Keyword(s):  
Carbon Monoxide ◽  
High Temperature ◽  
Combustion Process ◽  
Cylinder Pressure ◽  
Engine Operation ◽  
Hcci Engine ◽  
Gaseous Fuels ◽  
High Temperature Reaction ◽  
Temperature Combustion ◽  
Combustion Region

The effects of the introduction of the gaseous fuels, methane, hydrogen and carbon monoxide into the intake of a variable compression ratio n-heptane fuelled HCCI, CFR engine were investigated. The variations in some of the key combustion and operational parameters were determined experimentally. These included cylinder pressure and its rise rate temporal developments, autoignition timing, combustion durations for both the low and high temperature reaction regions, COV values for IMEP and maximum cylinder pressure, and the incidence of knock and its intensity. In parallel with the experimental investigation, results of a numerical simulation of the processes involved obtained by employing a KIVA based approach while incorporating sufficiently detailed chemical kinetics are presented. It was found that supplementing n-heptane HCCI with gaseous fuels could inhibit the low temperature combustion region and delay to varying extents the high temperature combustion region. Methane admission produced lengthening of the delay to autoignition and extended the combustion durations. It is suggested that supplementing the liquid fuel with methane may be a means for controlling the combustion process of a liquid fuelled HCCI engine while obtaining higher power and acceptable levels of emissions without producing unacceptably heavy knock. However, the addition of hydrogen or carbon monoxide could not reduce the intensity of knock while improving power output.

Study of high-pressure air jet controlled compression ignition with compound thermodynamic cycle for combustion and emission formation process

2020 ◽  
pp. 146808742096933
Author(s):  
Xiangyu Meng ◽  
Sicheng Liu ◽  
Jingchen Cui ◽  
Jiangping Tian ◽  
Wuqiang Long ◽  
...  
Keyword(s):  
High Pressure ◽  
High Temperature ◽  
Low Temperature ◽  
Formation Process ◽  
Combustion Process ◽  
Thermodynamic Cycle ◽  
Compression Ignition ◽  
Temperature Reaction ◽  
Air Jet ◽  
High Temperature Reaction

A novel method called high-pressure air (HPA) jet controlled compression ignition (JCCI) based on the compound thermodynamic cycle was investigated in this work. The combustion process of premixed mixture can be controlled flexibly by the high-pressure air jet compression, and it characterizes the intensified low-temperature reaction and two-stage high-temperature reaction. The three-dimensional (3D) computational fluid dynamics (CFD) numerical simulation was employed to study the emission formation process and mechanism, and the effects of high-pressure air jet temperature and duration on emissions were also investigated. The simulation results showed that the NOx formation is mainly affected by the first-stage high-temperature reaction due to the higher reaction temperature. Overall, this combustion mode can obtain ultra-low NOx emission. The second-stage high-temperature reaction plays an important role in the CO and THC formation caused by the mixing effect of the high-pressure air and original in-cylinder mixture. The increasing air jet temperature leads to a larger high-temperature in-cylinder region and more fuel in the first-stage reaction, and therefore resulting in higher NOx emission. However, the increasing air jet temperature can significantly reduce the CO and THC emissions. For the air jet duration comparisons, both too short and too long air jet durations could induce higher NOx emission. A higher air jet duration would result in higher CO emission due to the more high-pressure air jet with relatively low temperature.

scholarly journals LASER SYSTEM FOR STUDYING THE DYNAMICS OF HIGH TEMPERATURE COMBUSTION

2019 ◽  
Vol 4 (2) ◽  
pp. 154-162
Author(s):  
Lin Li ◽  
Fedor Gubarev ◽  
Andrei Mostovshchikov ◽  
Alexander Ilyin
Keyword(s):  
High Temperature ◽  
Narrow Band ◽  
Laser System ◽  
Combustion Process ◽  
Visual Observation ◽  
Copper Bromide ◽  
Temperature Combustion ◽  
Temporal And Spatial ◽  
Combustion Processes ◽  
High Temperature Combustion

The paper is devoted to development of methods for studying the dynamics of high-temperature combustion of aluminum nanopowder.The difficulty in studying the combustion of nanopowders is the high temperature and intensity of light emissionduring the combustion process, which makes the visual observation virtually impossible.The paper discusses various schemes using laser radiation to study the combustion processes of metal nanopowders.Particular mentions the use of the laser monitor based on an active medium on copper bromide vapor to study the combustion process of various powders and mixtures.The laser monitor combines the functions of the narrow-band laser illuminator and the brightness amplifier, thereby achieving the visualization at a narrow gain wavelength. Therefore, the laser monitor can be used to observe the changes in the surface of a burning sample with high temporal and spatial resolution.

Study on Wear Mechanism of an AlSi–Hexagonal Boron Nitride Abradable Seal Coating

2015 ◽  
Vol 1095 ◽  
pp. 655-661 ◽  
Author(s):  
Tong Liu ◽  
Yue Guang Yu ◽  
Jie Shen ◽  
Jian Ming Liu ◽  
Qiu Yuan Lu
Keyword(s):  
High Temperature ◽  
Wear Mechanism ◽  
Hexagonal Boron Nitride ◽  
Xrd Analysis ◽  
Test Rig ◽  
Speed Test ◽  
Turbine Performance ◽  
Temperature Combustion ◽  
Combustion Region ◽  
High Temperature Combustion

To improve gas turbine performance, it is essential to decrease back flow gases in the high-temperature combustion region of turbo machine by reducing the shroud/rotor gap. An abradable seal coating will function effectively. Therefore, it is significant to identify and characterize the main wear mechanisms occurring on turbo machinery seals. A high temperature and speed test rig has been developed by BGRIMM for testing the AlSi–hBN abradable seal coating and Ti-6Al-4V dummy blade. Impact velocities between 150 and 300m·s-1 and incursion rates between 5.0 and 480 μm·s-1 have been applied. It was found that incursion rate has a greater impact on the wear mechanism of the AlSi–hBN coating, with tests at low incursion rate showing a obvious grooving and little micro-rupture, whereas tests at high incursion rate showing significant cutting and adhesion. The present work also shown that tests at low incursion rate related to a higher IDR, which means that blade suffered a serious wear. The investigation together with SEM and XRD analysis on the coating revealed both wear and adhesion occurred at the end of the test.

scholarly journals The Distribution of Gases within the Combustion Coal of a Cigarette

1973 ◽  
Vol 7 (2) ◽  
Author(s):  
R.R. Baker ◽  
K.D. Kilburn
Keyword(s):  
Molecular Weight ◽  
Carbon Monoxide ◽  
High Temperature ◽  
Low Temperature ◽  
Temperature Region ◽  
Low Molecular Weight ◽  
Mainstream Smoke ◽  
Carbon Oxides ◽  
Sampling Probe ◽  
Combustion Region

AbstractMeasurements have been made of the distribution of temperature and low molecular weight gases within a burning cigarette, using a sampling probe coupled directly to a mass spectrometer (or Bosch carbon monoxide meter). The interior of the combustion coal is effectively an oxygen-deficient pyrolytic region. The oxides of carbon are produced in two distinct regions: a high-temperature (about 400-800°C) combustion region and a low- temperature (about 150-400°C) pyrolysis region. In the high-temperature coal the carbonised tobacco acts very much as a classical oxidizing solid fuel bed of carbon to give the two carbon oxides (and water). In the low-temperature region behind the coaI tobacco decomposes to give a substantiaI proportion of the carbon oxides and a major proportion of the hydrocarbons found in mainstream smoke.

scholarly journals II. Ignition phenomena in mixtures of carbon monoxide and oxygen sensitized by hydrogen

1938 ◽  
Vol 167 (930) ◽  
pp. 292-318 ◽  
Keyword(s):  
Carbon Monoxide ◽  
Chemical Reaction ◽  
Special Interest ◽  
Combustion Process ◽  
Proper Understanding ◽  
Factors Affecting ◽  
Chain Reactions ◽  
Gaseous Fuels ◽  
Combustion Processes ◽  
Combustion Of Hydrogen

Not the least important factors affecting the utilization of gaseous fuels are the remarkable effects of small quantities of catalytic substances, the presence of which may initiate or entirely change the nature of a combustion process. A proper understanding of these factors is therefore of great importance in the control of processes which are fundamental to many parts of applied chemistry. Such processes, however, are also intrinsically interesting for the insight they give into the ultimate mechanism of chemical reaction, and as a result of their study in the light of the theory of chain reactions, many empirical facts relating to combustion processes which previously were obscure now acquire a new significance. Of all these reactions the combustion of hydrogen and carbon monoxide stand in a unique position, for these substances more than any others occur as intermediaries in the burning of gaseous fuels; it is therefore of special interest to realize that the presence of traces of hydrogen may have a profound effect on the combustion of carbon monoxide, not only in lowering the temperature of ignition, but also in influencing the rate of propagation of the flame. This becomes of particular importance when it is remembered that carbon monoxide as used industrially nearly always contains traces of hydrogen.

Progress on Facilities and Methodology to Evaluate Abradable Seal Coatings

2013 ◽  
Vol 690-693 ◽  
pp. 1992-1998
Author(s):  
Qiu Yuan Lu ◽  
Jie Shen ◽  
Yue Guang Yu ◽  
Xian Jing Ren ◽  
Hai Jun Xuan ◽  
...  
Keyword(s):  
High Temperature ◽  
Gas Turbine ◽  
Working Conditions ◽  
Analytical Methods ◽  
Turbine Performance ◽  
Detection Technology ◽  
Experimental Parameters ◽  
Temperature Combustion ◽  
Combustion Region ◽  
High Temperature Combustion

To improve gas turbine performance, it is essential to decrease back flow gases in the high-temperature combustion region of the turbo machine by reducing the shroud/rotor gap. An abradable seal coating will function effectively. The present work described an advanced detection technology and test rigs to study abradability of the seal coatings. Several early used analytical methods were also reviewed in the work as comparison,like NASAPWA and Sulzer Innotec, have developed abradable test rigs and specified different experimental parameters by simulating the determined working conditions. Thence, suggestions to further develop evaluation methods for seal coatings were proposed and discussed.

Effect of oxidative torrefaction on high temperature combustion process of wood sphere

Fuel ◽  
2021 ◽  
Vol 286 ◽  
pp. 119379
Author(s):  
Xin Li ◽  
Zhimin Lu ◽  
Jinzheng Chen ◽  
Xiaoxuan Chen ◽  
Yuan Jiang ◽  
...  
Keyword(s):  
High Temperature ◽  
Combustion Process ◽  
Temperature Combustion ◽  
High Temperature Combustion

The Effect of the Residence Time in the High Temperature Field on the Fullerene and PAH Formation Mechanism

2011 ◽  
Author(s):  
Tatsuya Saika ◽  
Youhei Sakita ◽  
Masahiko Shibahara
Keyword(s):  
High Temperature ◽  
Residence Time ◽  
Formation Mechanism ◽  
Flue Gas ◽  
Combustion Process ◽  
Hydrocarbon Fuel ◽  
Experimental Conditions ◽  
Reduced Pressure ◽  
Reaction Field ◽  
High Temperature Reaction

Fullerenes were generated and observed in the combustion processes of hydrocarbon fuel under reduced pressure conditions however the fullerene formation mechanism from PAHs in fuel rich hydrocarbon flames under reduced pressure conditions has not been clarified yet. In the present study, the effects of the residence time in the high temperature reaction field were investigated experimentally and the effects of the residence time on the contents of fullerenes and PAHs were discussed. The experimental results showed that the contents of fullerenes as well as PAHs in the total soot collected from the flue gas decreased with the increase of the residence time in the range from 800 to 1500 degree Celsius. On the other hand, the contents of fullerenes in the total soot decreased with the increase of the residence time over 1500 degree Celsius because the total PAHs contents in the flue gas increased under the present experimental conditions. It is essential for the fullerene generation to realize the optimal residence time from 800 to 1500 degree Celsius as well as that over 1500 degree Celsius with an appropriate PAH partial pressure in the combustion process.

Kinetics of the high temperature reaction of carbon monoxide with nitrous oxide

1987 ◽  
Vol 91 (8) ◽  
pp. 2144-2148 ◽  
Author(s):  
Nobuyuki. Fujii ◽  
Tomohisa. Kakuda ◽  
Nobuhiro. Takeishi ◽  
Hajime. Miyama
Keyword(s):  
Carbon Monoxide ◽  
Nitrous Oxide ◽  
High Temperature ◽  
Temperature Reaction ◽  
High Temperature Reaction ◽  
Kinetics Of

scholarly journals THE RESEARCH OF IGNITION AND COMBUSTION OF ALUMINUM AND MAGNESIUM ALLOYS IN THE PRODUCTS OF DECOMPOSITION OF SOLID PYROTECHNICAL FUELS

2020 ◽  
Vol 1 (2) ◽  
pp. 81-85
Author(s):  
R Motrichuk ◽  
O Kyrychenko ◽  
O Dibrova ◽  
V Vashchenko ◽  
S Kolinko
Keyword(s):  
High Temperature ◽  
Magnesium Alloys ◽  
Fire Hazard ◽  
Combustion Process ◽  
Combustion Products ◽  
Temperature Combustion ◽  
Pyrotechnic Mixtures ◽  
Aluminum Magnesium Alloys ◽  
Ignition And Combustion ◽  
Aluminum And Magnesium Alloys

The results of experimental research of processes of ignition and combustion of particles of aluminum and magnesium alloys in gaseous purges of high-temperature decomposition of solid pyrotechnic fuels leading to their fire explosive hazardous development are presented. The relevance of these research is due to the wide scope of application of pyrotechnic products based on pyrotechnic mixtures of powders of aluminum-magnesium alloys with additives of organic substances, in particular applications in military technology and use in various industries related to the rotation of solid pyrotechnic equipment. Accordingly, in case of fire at facilities where pyrotechnic products are kept or during their transportation there exists the risk of ignition of pyrotechnic mixtures with different acceleration of their subsequent combustion process and destruction of the pyrotechnic products. As a result, high-temperature combustion products are formed, which are fire hazardous to the surrounding environment. Based on the foregoing, it is necessary to obtain data on the regularities of ignition and combustion particles of aluminum-magnesium alloys, which determines the ability to predict the properties of fire hazard pyrotechnic mixtures.  As a result of conducted research, data on the ignition and combustion of particles of aluminum-magnesium alloys was obtained, in particular, the dependence of the delay time of the particles of aluminum-magnesium alloys on their chemical composition was obtained, the data on the process of combustion of particles of aluminum-magnesium alloys was obtained, the data on the effect of additives to aluminum-magnesium alloys was obtained.

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