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1

The influence of injection timing on the combustion characteristics for the heterogeneous combustion field using impinging injection

Kawakami T.

Journal of KONES

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2018

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Vol. 25, No. 3

283--288

EN

It is very important to achieve the low particulate and low emissions under high power operation conditions in practical industrial engine and turbine combustion. Several techniques for reducing the emissions have been proposed and a large amount of experimental data has been published. It is well known that the combustion field in practical industrial diesel engine are strongly influenced by the behaviour of injection, distribution of droplets and the premixed ratio of the combustion chamber. As the first step of this study, experiments have been carried out to examine the combustion characteristics of heterogeneous combustion field by using impinging injection and Split injection in a closed chamber. The combustion chamber is equipped with pintle type injection nozzles on each of the opposite walls along the length of the bomb. In this study, we call it “impinging injection” when the injection is performed at same time by two nozzles facing each other and “split injection” when the impinging injection is performed at two different timing. The main conclusions are as follows: 1) the most suitable conditions of injection timing exists for improving the maximum burning pressure and total burning time by using impinging injection; 2) the flame speed can be possible to control by using impinging injection timing from the ignition; 3) the heat release rate for Split injection is larger than that of standard impinging injection.

2

Combustion characteristics by using multicomponent alcohol blended fuels for the small diesel engine

Kawakami T.

Archivum Combustionis

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2017

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Vol. 37 nr 2

155--161

EN

Nowadays, bio fuel has been expected as substitution of petroleum fuels. Being that it is produced by plants, it has become the sustainable and carbon neutral fuel. Of course, the CO2 emission don’t increase after using them as fuels of the automobiles and industry because of the bio fuels are produced by plants. Based on these factors, the demand of bio fuels has been expected to more spread in recent years. The Ethanol and Butanol have been produced as bio fuels, it is well known that the ignitability of both fuels are lower than that of the light oil, furthermore, it is necessary to improve for the emission characteristics and the heat release rate. This experiment has been carried out to examine the combustion characteristics of a small diesel engine by using the ethanol and butanol (1-butanol, 2-butanol and iso-butanol) for bio alcohol fuel. Furthermore, DGM (Diethylene Glycol Dimethyl Ether) and DMC (Dimethyl Carbonate) are also used for a comparison for bio alcohol fuels.

3

A study of combustion improvement for flame propagation in a tube by using combination flow and mixture injection

Kawakami T.

Journal of KONES

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2016

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Vol. 23, No. 1

147--152

EN

Experiments on combustion of lean mixtures in the vicinity of flammability limit have acquired importance from the viewpoint of development of new kinds of combustion system with low fuel consumption and low emissions. It is well known that the combustion characteristics near the lean limit are instability and low heat release rate. Therefore, it is necessary to improve the combustion behaviour by using several techniques. Experiments have been carried out to examine the influence of combination flow and mixture injection on flame behaviour and flame propagation speed for lean premixed propane-air mixtures in a combustion tube. The mail conclusions are as follows: 1) The Average flame speed with the swirl flow is remarkably increased as compared with the case of laminar flow. 2) The Average flame speed by using the combination flow is bigger than that of the swirl flow. 3) By changing the combination flow intensity, it is possible to control the flame speed. 4) The flame speed by using injection of premixed mixture to flame front is higher than that of laminar flame speed without the mixture injection. 5) The most suitable conditions exit for combustion improvement near the flammability limit by using the mixture injection.

4

Experimental study of emission reduction by using alcohol blended fuel for small gasoline engine

Kawakami T.

Journal of KONES

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2015

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Vol. 22, No. 2

115--120

EN

In practical gasoline engines it is necessary to achieve low emissions and low fuel consumptions with high load operation. Several techniques were developed for reducing the emissions and the fuel consumptions from gasoline engines, such as EGR (exhaust gas recirculation) and Ultra lean combustion [1, 2]. Especially, in automotive gasoline engines, low-particulate and low-NOx emissions are very much needed by using alcohol blend fuels and vegetable oil. Nevertheless, there are only few data available for reducing the emissions and fuel consumptions of small gasoline engines by using blended fuels. As the first step in this study, experiments have been carried out to examine the influence of alcohol-blended fuels on combustion characteristics for small gasoline engines. The fuels used in this study are gasoline, methanol, ethanol, propanol and butanol. The addition of alcohol ratio are changed by mixing the volume of alcohol in gasoline and the addition ratios are from 0 to 30 vol% in the fuel. The main conclusions are as follows: 1) The NOx emissions for all the alcohol blend fuels are smaller than that of gasoline. 2) The heat release rate increases with addition of alcohol fuel under higher load conditions for small gasoline engines.

5

A study of emission reduction by using alcohol blend fuel for small diesel engine

Kawakami T.

Journal of KONES

|

2014

|

Vol. 21, No. 1

125--130

EN

In practical diesel engines it is to achieve a low emission and low fuel consumption under from low to high load operation conditions. Several techniques were developed for the low emission and high efficiency, such as Homogeneous Charge Compression-Ignition Engines and the blend fuels. Nevertheless, there are only few data available for reducing the emissions and fuel consumption of small diesel engines by using blend fuels. This experiment has been carried out to examine the influence of alcohol blend fuels on combustion characteristics for small diesel engine. The fuels used in this study are light oil (Standard), ethanol, propanol and butanol. The combustion behaviours, such as the emissions in exhaust gas (NOX, CO, CO2, O2 concentration), fuel consumption rate are observed. The main conclusions are as follows: 1) it is possible to control the combustion behaviour by using alcohol blend fuels for small diesel engine, 2) the fuel consumption of at any alcohol blend fuels is bigger than that of light oil, 3) the net thermal efficiency of some alcohol blend fuels (E5P5, P5B5, E5B5) slightly increases than that of light oil, 4) the NOx emissions for all the alcohol blend fuels are smaller than that of light oil, 5) the CO emissions are remarkably bigger than that of light oil under from low to middle engine load without the ethanol 10% addition.

6

A manufacturing network for generating added value from a geographical distance for the next generation

Yukawa K., Kawakami T.

Journal of Machine Engineering

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2011

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Vol. 11, No. 3

44--57

EN

n this study, we suggested a manufacturing network for generating added value from a geographical distance in terms of value creation from various management resources. Until today, most researchers focused on the Real Concentration of Production Base, which provides certain manufacturing benefits in these domains. However, "the Virtual Concentration of Production Bases" is realized by overcoming large physical distances and time differences between production bases, and creates greater added value for products. We attempted the simulation of the manufacturing network of creating the added value after having shown the new framework of network analysis in the manufacturing system.

7

Combustion characteristics for small diesel engine by using emulsified blend fuels of vegetable oil and light oil

Kawakami T.

Journal of KONES

|

2011

|

Vol. 18, No. 4

185-190

EN

The paper is focusing on combustion characteristics for small diesel engine by using emulsified blend fuels of vegetable oil and light oil. Target is to achieve low emissions and low fuel consumption for internal combustion engines. The fuels used in this study are light oil, blend fuels [light oil + coconut oil, light oil + palm oil], and emulsified fuels [light oil + water, blend fuels + water]. Mean increasing rate of pressure is calculated from the value which subtracted initial pressure from maximum burning pressure divided by total burning time. The mean increasing ratio of pressure is calculated from the value which subtracted initial pressure from maximum burning pressure divided by the total burning time. The emissions in exhaust gas are measured with an analyzer of exhaust gas. The data of 30 tests for each engine revolutions were averaged arithmetically. Experimental approach and results have been presented by details. The main conclusions are as follows: it is possible to control the combustion behaviour by using blend fuels and emulsified blend fuels for small diesel engine; the maximum burning pressure of emulsified blend fuels increases at low engine speed; the CO emission of blend fuels is smaller than that of light oil; the NOX emission of emulsified coconut blend fuel and emulsified palm blend fuel is smaller than that of light oil; the CO emission of emulsified Coconut-Palm blend fuel is equal to that of light oil at low engine speed.

8

A study of combustion characteristics of emulsified vegetablelight oil in small diesel engine for reduction of emissions

Nakashima R., Kawakami T.

Silniki Spalinowe

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2009

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R. 48, SC2

254--257

EN

Internal combustion engines are the major source of air pollution. Especially, compression ignition engines in today’s industrial and automotive general engines contribute the most to NOx, CO, particulate emission and soot, and it is recognized that these emissions have a detrimental effect on human and earth environment. So an improvement of spray combustion for diesel engines is of urgent necessity. From this point, experiments have been carried out to obtain the essential data on spray combustion influenced by blend fuel with emulsion in small diesel engine. The main conclusion are as follows: 1) The maximum burning pressure of blend oil with emulsion is smaller than that of light oil; 2) NOx emission of the blend oil with emulsion is smaller than that of light oil.

9

Influence of Blend Fuels on Combustion Characteristics for Small Diesel Engine

Sugiyama H., Kawakami T., Teodorczyk A.

Archivum Combustionis

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2008

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Vol. 28 nr 3-4

206-214

EN

As a possible solution for the run out of fossil fuel resources and the climate warming caused by the CO2 emission, the fuel with the content of vegetable oil has been used in our studies as an alternative fuel for light oil. However, operating the diesel engine with vegetable oils, results in increased NOx emissions as compared with the case of light oil. So, this study has been carried out to examine the influence of composition of blend of fuels on combustion characteristics and exhaust emissions in small diesel engine. The blends of light diesel oil and coconut oil with water were used. The range of blend ratio of coconut oil in light diesel oil was 0 to 20 vol %. The content of water in fuel was 0 to 20 by mass %. The maximum burning pressure and total burning time were observed by measuring the pressure with piezoelectric Kistler pressure transducer. The main conclusions are as follows: 1) The maximum burning pressure for water emulsion oil is smaller than that of light oil. 2) NOx emission of light fuel with coconut oil is higher than that of light oil.3) It is possible to improve the combustion behavior by using blend fuels for small diesel engines.

10

Effects of Water Vapor and CO2 Addition on Combustion Characteristics for Lean Hydrocarbon-Air Mixtures under Normal and Microgravity Conditions

Shibata Y., Kawakami T., Teodorczyk A.

Archivum Combustionis

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2008

|

Vol. 28 nr 3-4

197-205

EN

Experiments on combustion of extremely lean mixtures in the vicinity of flammability limits have acquired importance from the viewpoint of development of new kinds of combustion systems having low fuel consumption and low emissions. Furthermore, the determination of combustion characteristics for vapor addition under normal gravity and microgravity is very important for control of safety engineering in the space. In this work, experiments have been carried out with extremely lean, quiescent hydrocarbon-air mixtures to examine the effects of water vapor and CO2 addition on combustion characteristics under normal gravity and microgravity conditions. The microgravity technique achieved in a freely falling chamber is employed because the realizations of symmetrical flame propagations in a tube are impossible. Experimental condition for the initial mixtures corresponds to room temperature and 0.1MPa and the fuels used are methane and propane of 99.9% purity, respectively. The experimental results in this study are as follows. : 1) The water vapor addition for low oxygen concentration of propane-air mixtures effectively increases the flame speed; 2) Effects of water vapor addition on flame speed depend on a fuel property; 3) It is possible to control the combustion behavior by water vapor addition in the mixtures under low oxygen concentration.

11

Influence of oxygen concentration on combustion characteristics of hydrocarbon-air mixtures under high temperature and pressure

Kanno A., Kawakami T., Sutkowski M., Teodorczyk A.

Journal of KONES

|

2006

|

Vol. 13, No. 2

197-203

EN

The emission of NOx, SOx, HC and CO2 from internal combustion engines is still a major issue in the development of modern engines. Especially for new concepts, like EGR (Exhaust gas recirculation), developed, detailed information about the pollutant formation is required. However, the experiments of actual standard engines are generally very complicated processes including the residual gas from the last cycle and the flow in an engine cylinder. Thus, experimental data measured using actual engines become unreliable. To obtain the essential data on combustion of hydrocarbon-CO2-N2-O2 mixtures, the experiments have been performed under conditions of high temperature and pressure, which are achieved by a spark ignited opposed rapid compression machine. The main conclusions are as follows: (1) The maximum burning pressure decreases with decreasing oxygen concentration at same EGR ratio. (2) The total burning time decreases with decreasing the concentration of O2 in methane-COx-N2-O2 and propane-CO2-N2-O2 mixtures. (3) The reduction ratio of flame speed is relatively larger on the fuel rich side than that on the lean side. Numerical modeling was focused on the influence of EGR ratio on exhaust emission. Methane fuel was used in the modeling

12

Experimental study of combustion improvement for small gasoline engine

Tajima M., Kawakami T.

Journal of KONES

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2006

|

Vol. 13, No. 2

421-426

EN

In practical gasoline engines it is necessary to achieve a low emissions and low fuel consumption with high load operation. Several techniques were developed for reducing the emissions and fuel consumption from gasoline engines, such as EGR (exhaust gas recirculation) and Ultra lean combustion. Nevertheless, there are only very few data available for reducing the fuel consumption in small gasoline engines (50-125cc). As the first step of this study, experiments have been carried out to examine the influence of oxygen concentration in intake air and fuel concentration on flame speed in small gasoline engine by using carburetor and EFI system. The flame front travel time was measured using ionization probes located at different point of cylinder head. The main conclusions are as follows: 1) the flame speed monotonically increases with increasing the engine rotation at any concentration in intake air; 2) Mean increasing rate of pressure is not affected by oxygen concentration in intake air and fuel concentration without load; 3) It is possible to improve the combustion behavior by using EFI system for small gasoline engine.

13

Experimental investigation of combustion characteristics for spray combustion by impinging injection in a closed vessel

Morioka K., Kawakami T., Teodorczyk A.

Journal of KONES

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2006

|

Vol. 13, No. 2

335-339

EN

Internal combustion engines are the major source of air pollution. Especially, compression ignition engines in today’s automobiles contribute the most to particulate emission and soot, and it is recognized that these emissions have a detrimental effect on human and earth environment. So, an improvement of spray combustion for diesel engines is of urgent necessity. Experiments have been conducted to obtain essential data on spray combustion influenced by impinging injection in a closed vessel. The effect of the impinging injection on maximum burning pressure, total burning time and flame speed is investigated at the condition of 300 K of initial temperature and 0.1 MPa of initial pressure. The travel time of flame front is measured by ionization probes located at two different positions from the center of combustion chamber. The experimental investigations pointed out that the maximum burning pressure for impinging injection is larger than that of the single injection at the same overall equivalence ratio, the total burning time increases with increasing the overall equivalence ratio (after injection) at same equivalence ratio (before injection), the combustion of impinging injection is very effective for increasing the flame speed.

14

Combustion characteristics of lean propane-air mixture by using high ignition energy

Kawakami T., Okajima S., Teodorczyk A.

Journal of KONES

|

2004

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Vol. 11, No. 1-2

308-313

EN

Experiments have been carried out to examine the combustion characteristics of propane-air mixtures under normal gravity and microgravity conditions by using high ignition energy in a combustion tubę. The microgravity technique achieved in a freely falling chamber is employed because the realizations of symmetrical flame propagations in a tubę are possible. Experimental condition for the initial mixtures corresponds to room temperature and 0.1 MPa and the fuel used is propane of 99.9% purity. The main conclusions are as follows: (J) The flame speed monotonically decreases with decreasin the equivalence ratio under normal gravity and microgravity. (2) The probability of the irregular flame propagation for both fuels under microgravity are larger than that under normal gravity at same equivalenence ratio. (3)The range of distance of flame propagation under normal and microgravity conditions by using high ignition energy can possible to distinguish.

15

Injection of lean mixtures into hot burned gas for maintaining lownox emissions over an extended range of fuel-air ratios in prevaporized combustion

Kawakami T., Aida N., Nishijima T., Yamada H., Hayashi S.

Journal of KONES

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2003

|

Vol. 10, No. 3-4

137-148

EN

“Flameless combustion” of lean to ultra lean mixtures, supported by hightemperature burned gas, can resolve the dilemma between complete combustion versus ultralow NOx emissions in gas turbine combustors. The characteristic of NOx emissions and combustion in “leanlean” twostage combustion was investigated for premixedprevaporized keroseneair mixtures using a coaxial flow configuration. A circular jet of secondary keroseneair mixtures of lean to ultralean compositions were injected into the primary hot burned gas prepared by combustion of lean mixtures on an annular perforated flame holder The progress of reaction and NOx formation in the combustion tube were measured for nonswirled and swirled secondary jets. The conditions required for complete combustion of the secondary mixtures were defined for various ratios of secondary to primary air flow rates.

16

A study of flame propagation limit of very lean propane-air mixture in a combustion tube

Kawakami T., Okajima S., Teodorczyk A.

Journal of KONES

|

2003

|

Vol. 10, No. 3-4

149-153

EN

Experiments have been carried out with extremely lean, quiescent propaneair mixtures to examine the influence of flame propagation direction under normal gravity and microgravity conditions on propagation limit and distance of flame propagation in a tube. The microgravity technique achieved in a freely falling chamber is employed because the realizations of symmetrical flame propagations in a tube are possible. Experimental condition for the initial mixtures corresponds to room temperature and 0.1 MPa and the fuel used is propane of 99.9% purity. The experimental results show that the range of distance of flame propagation under normal and microgravity conditions can possible to distinguish under follows: i)Range : the flame propagation was observed under normal and microgravity conditions (Flammability limit), ii)Range : the flame propagation was influence by gravity condition (Unsteady Range), iii)Range �f: under microgravity the flame propagation was observed (Microgravity Range) and iv)Range‡V : the flame propagation was not observed under normal and microgravity conditions (Without flammability limit under normal and microgravity conditions).

17

Some new experimental observations of combustion characteristics near lean limit in a tube under microgravity

Kawakami T., Okajima S., Teodorczyk A.

Journal of KONES

|

2002

|

Vol. 9, No. 1-2

110-116

EN

Experiments have been carried out with extremely lean, quiescent propane-air mixtures to examine the behavior of irregular flame propagation and to examine the lean limits of flame propagation in a tube under microgravity. The microgravity technique achieved in a freely falling chamber is employed because the realizations of symmetrical flame propagations in a tube are possible. Experimental conditions for the initial mixtures correspond to room temperature and 0.1 MPa and the fuel used is propane of 99.9% purity. The experimental results show that (1) though the lean limit of the flame propagation in a tube decreases with increasing diameter, it holds constant when the tube diameter is more than 50 mm, (2) with a large combustion tube, the lower flammability limit shifts to as low as . = 0.15 of equivalence ratio under microgravity, (3) the irregular flame fronts of cellular nature are observed in a narrow range of 0.35 < . < 0.55 under microgravity, (4) the lowest measured value of flame speed is of the order of 11.5 cm/s under microgravity which is less than half of that observed under normal gravity, and (5) the influence of radiation from the wall in a tube on flame speed appears negligible.

18

Influence of exhaust gas recirculation on combustion characteristics under high temperature and pressure using opposed rapid compression machine

Kawakami T., Okajima S., Teodorczyk A.

Journal of KONES

|

2002

|

Vol. 9, No. 1-2

104-109

EN

The release of NOx, SOx, HC and CO2 from internal combustion engines is still a major issue in the development of modern engines. Especially when new concepts like EGR (Exhaust gas recirculation) are developed, detailed information about the pollutant formation is required. However, the experiments of actual standard engines are generally very complicated processes including the residual gas of last cycle and the flow in an engine cylinder. Thus, experimental data measured using actual engines become unreliable. To obtain the essential data on combustion of hydrocarbon-CO2-N2-O2 mixtures, the experiments have been performed under conditions of high temperature and pressure, which are achieved by a spark ignited opposed rapid compression machine. The main conclusions are follows: (1) Flame speed decreases with increasing the concentration of carbon dioxide. (2) The reduction rate of the flame speed decreases with increasing the compression ratio.(3) The ratio of decrease of flame speed increases with increasing carbon dioxide concentration.

19

Preliminary experimental study of autoignition of hydrogen-oxygenmixture by using combustion driven rapid compression machine

Dąbkowski A., Kawakami T., Teodorczyk A.

Journal of KONES

|

2001

|

Vol. 8, No. 1-2

45-51

EN

The rapid compression machine designed and constructed at Warsaw University of Technology creates high pressure and temperature at the end of compression stroke, leading to mixture autoignition with the possibility of the process visualization. The unique feature of the machine is the possibility ofstudyingignitionand combustion processessimilar to those existing in the engines with gas fuel injecteddirectlyto combustion chamber. The adequate characteristics of piston movement is achieved by conventional crank mechanism, however the required acceleration is introduced by the combustion of fuel-oxygen mixture under the piston. Calculationsand preliminary tests have shownthat the method is capable to achieve piston accelerations equivalentto engine rotational speedof 5000 rpm. The test chamber is equipped with pressure transducer that together with electronic piston movement transducer enables for registration of pressure profile with respect to crack angle. The light signal from the flame in the chamber is transmitted by the light pipe to phototransistor. All signals are collected by computerdata acquisition system. The preliminary study of autoignition of hydrogen-oxygen mixture was performed with the use ofthis apparatus and the results are discussed.

20

A study of combustion characteristics of hydrocarbon-air mixtures at high temperature and pressure by using rapid compression machine

Kawakami T., Okajima S., Teodorczyk A.

Journal of KONES

|

2001

|

Vol. 8, No. 1-2

52-57

EN

Experiments have been carried out with quiescent hydrocarbon-air mixtures for determining their combustion characteristics, under high temperature and pressure using a single and an opposed rapid compression machine with spark ignition. The absolute value of pressure exponent for methane-air and propane-air mixtures increases with increasing initial temperature and the temperature exponent is estimated to be about 2.6 even at high temperature and pressure conditions.