• Journal of the Korean Society of Combustion
• /
• v.11 no.2
• /
• pp.28-36
• /
• 2006

A constant volume combustion chamber was used to investigate the combustion characteristics. of homogeneous charge of methane-air mixture under various initial pressure, equivalence ratio and ignition times. The constant volume combustion chamber(CVCC) mostly has been studied by the experiments of visualization until now. So it is needed the numerical analysis of fluid and combustion characteristics in chamber by the more detail simulation. In this paper, the numerical analysis is tried to approach basically the homogeneous charge combustion phenomena under the various conditions, and the combustion phenomena in chamber is numerically analyzed by the commercial FIRE code. As a results, the combustion phenomena which were mean temperature, OH radical and reaction rate in chamber were investigated and it showed that the smallest flame growth occurs for the lean state and the increase of initial charged pressure condition due to the reduced OH radical.

• Journal of the Korean Society of Industry Convergence
• /
• v.6 no.3
• /
• pp.193-200
• /
• 2003

In the production of internal combustion engines, there has been a move towards the development of high performance engines with improved fuel efficiency, lighter weight and smaller sizes. These trends help to answer problems in engines related to thermal load and abnormal combustion. In order to investigate these problems, a thin film-type probe for instantaneously measuring temperatures has been suggested. A method for manufacturing such a probe was established in this study. The instantaneous surface temperature of a constant volume combustion chamber was measured by this probe and the heat flux was obtained through Fourier analysis. In order to thoroughly understand the characteristics of combustion, the authors measured the wall temperature of the combustion chamber and computed heat flux through a cylinder wall while varying the protrusion height of the probe. For achieving the above goals, a instantaneous temperature probe was developed, thereby making possible the analysis of the instantaneous temperature of wall surface and the detection of unsteady heat flux in the constant volume combustion chamber.

• Transactions of the Korean Society of Automotive Engineers
• /
• v.12 no.2
• /
• pp.45-53
• /
• 2004

An experimental study was carried out to obtain the fundamental data about the effects of radicals induced injection on premixture combustion. A constant volume combustor divided to the sub-chamber and the main chamber was used. The volume of the sub-chamber is set up to occupy less than 1.5％ of that of whole combustion chamber. Radial twelve narrow passage holes are arranged between the main chamber and the sub-chamber. The products including radicals generated by spark ignition in the sub-chamber will derive the simultaneous multi-point ignition in the main chamber. While the equivalence ratio of pre-mixture in the main chamber and the sub-chamber is uniform. We have examined the effects of the sub-chamber volume, the diameter of passage hole, and the equivalence ratio on the combustion characteristics by means of burning pressure measurement and flame visualization. In the case of radical ignition method(RI), the overall turning time including the ignition delay became very short and the maximum burning pressure was slightly increased in comparison with those of the conventional spark ignition method(SI), that is, single chamber combustion without the sub-chamber. The combustible lean limit by RI method is extended to more ER=0.25 than that by SI method. Therefore the decrease of every emission including NOx and the improvement of fuel consumption is anticipated due to lean burn.

• Transactions of the Korean Society of Automotive Engineers
• /
• v.1 no.1
• /
• pp.66-79
• /
• 1993

To construct the design back data for a lean-burn gas engine, we have designed a constant volume combustion chamber with sub-chamber. With constant volume ratio of main-sub combustion chamber and constant equivalence ratio of methane-air mixture, the influence of geometric configurations(diameter, injection angle, number, length) of passagehole upon combustion characteristics were studied. It was found that combustion characteristics in the main combustion chamber were greatly influenced by the injection angle and length of passagehole.

• 한국연소학회:학술대회논문집
• /
• 2002.11a
• /
• pp.223-229
• /
• 2002

Spark plug ionization signal could be useful in an internal combustion engine as a feedback signal for combustion diagnostics such as misfire detection, knocking detection and lambda control, but the signal has high level of cyclic fluctuation in an internal combustion engine due to residual gas, pressure, temperature, mixture composition in the spark gap. Because of this reason it is very difficult to apply ion signal to commercial engine control. In this Study, a correlation between A/F and spark plug ionization signal was studied in a constant volume chamber. Constant volume chamber with gas phase fuel(Propane) has homogeneous fuel composition , no mixture flow, same pressure and temperature on each test. The results show that mean chemi-ion signal has the highest correlation with A/F and intial pressure change has on effect on the thermal-ion signal and not on chemi-ion signal.

• Transactions of the Korean Society of Automotive Engineers
• /
• v.8 no.4
• /
• pp.10-17
• /
• 2000

This work presents an investigation of aerodynamic characteristics of fuel spray injected from a high pressure hollow cone swirl injector into a constant volume chamber. Laser tomography visualization was used to interrogate the fuel and air mixing characteristics and the effect of chamber pressure and temperature increase was analyzed, Preliminary results on spray development showed that mixing effect tends to increase with the increase of injection pressure and chamber gas pressure yielding a decrease of spray penetration and an attenuation of well-defined vortex structure. Topological analysis of the spray structure has been performed to initiate the understanding of mixing and vaporization process. For the present experimental conditions fuel injection pressure and chamber gas pressure appear as the dominant factors which govern the transient mixing characteristics. Moreover spray atmixation characteristics are improved by increasing chamber gas temperature.

• Journal of Power System Engineering
• /
• v.21 no.3
• /
• pp.12-18
• /
• 2017

Diesel and gasoline engines will be used as main power system of automobiles. Recently, engine downsizing is widely applied to both gasoline and diesel engines in order to improve fuel economy and exhaust emissions. Engine downsizing means small engine combustion chamber with higher combustion pressure. Therefore, spray and combustion process should be investigated under these high pressure and temperature conditions. In this study, constant volume combustion chamber which enables easy optical access from six directions was developed. Combustion chamber was designed to resist maximum pressure of 15 MPa and maximum temperature of 2,000 K. Combustible pre-mixed mixture was introduced into combustion chamber and ignited by spark plugs. High pressure and temperature were implemented by combustion of pre-mixed mixture. Three initial conditions of different pressure and density were tested. High repeatability of combustion process was implemented which was proven by low standard deviation of combustion pressure.

• Journal of Advanced Marine Engineering and Technology
• /
• v.21 no.3
• /
• pp.302-310
• /
• 1997

In this paper, we find a method to improve ignitability using methanol which is prospective as an alternative fuel. The constant volume combuster is divided into main chamber and sub-cham¬ber. These two chambers are linked by an adapter which is shaped like a cup. We also compare CDI to HIS that is revised in our laboratory for making a scrutiny into the effects of ignition char¬acteristics. Besides, we analyze a flame propagation process in the main and sub-chamber through taking pictures 10, 000 frames per second by high speed camera at the state being fabricated quartz glass aside main and sub-chamber.

• Journal of Advanced Marine Engineering and Technology
• /
• v.28 no.7
• /
• pp.1055-1062
• /
• 2004

As for the Production of internal combustion engines there has been further movement toward development of high Performance engines with improved fuel efficiency as well as a lightweight and a small size. These tendencies help to solve the problems in engines for example, such as thermal load. abnormal combustion and so on. In order to investigate these Problems, a thin film-type probe for measuring instantaneous temperature has been suggested. A method for manufacturing such a probe was established in this study The instantaneous surface temperature of a constant volume combustion chamber was measured by using this probe and the heat flux was obtained through Fourier analysis In order to thoroughly understand the characteristics of combustion. authors measured wall temperature of combustion chamber and calculated heat flux through a cylinder wall while varying the protrusion height of probe. For these Purposes, the instantaneous surface temperature probe was developed. thereby making possible the analysis of instantaneous temperature of wall surface and the detection of unsteady heat flux in the constant volume combustion chamber.

• Journal of Mechanical Science and Technology
• /
• v.18 no.9
• /
• pp.1623-1629
• /
• 2004

The objective of this study is the rapid bulk combustion of mixture in a constant volume chamber with a tiny sub-chamber. Some narrow passage holes were arranged to induce simultaneous multi-point ignition in the main chamber by jet of burned and unburned gases including radicals from the sub-chamber, and the equivalence ratios of pre-mixture in the main chamber and the sub-chamber were the same. The principal factors of the Radical Induced Auto-Ignition (RIAI) method are the diameter of the passage holes and the volume of sub-chamber. The relationship between the sub-chamber and diameter of passage hole was represented by the ratios of sub-chamber volume to passage hole volume. The ratios are non-dimensional coefficients for sub-chamber characteristics. As a result, the RIAI method reduced the combustion period, which expanded the lean limit in comparison with SI method.