Go to the main menu
Skip to content
Go to bottom
REFERENCE LINKING PLATFORM OF KOREA S&T JOURNALS
> Journal Vol & Issue
Transactions of the Korean Society of Automotive Engineers
Journal Basic Information
Journal DOI :
The Korean Society of Automotive Engineers
Editor in Chief :
Volume & Issues
Volume 15, Issue 6 - Nov 2007
Volume 15, Issue 5 - Sep 2007
Volume 15, Issue 4 - Jul 2007
Volume 15, Issue 3 - May 2007
Volume 15, Issue 2 - Mar 2007
Volume 15, Issue 1 - Jan 2007
Selecting the target year
Developments of a Path Planning Algorithm and Simulator for Unmanned Ground Vehicle
Kim, Sang-Gyum ; Kim, Sung-Gyun ; Lee, Yong-Woo ;
Transactions of the Korean Society of Automotive Engineers, volume 15, issue 3, 2007, Pages 1~9
A major concern for Autonomous Military Robot in the rough terrain is the problem of moving robot from an initial configuration to goal configuration. In this paper, We generate a local path to looking for the best route to move an goal configuration while avoiding known obstacle from world model, not violating the mobility constraints of robot. Trough a Simulator for Unmanned Autonomous Vehicle, We can simulate a traversability of unmanned autonomous vehicle based on steering, acceleration, braking command obtained from local path planning.
Design of a Heat Exchanger to Reduce the Exhaust Temperature in a Spark-Ignition Engine
Lee, Seok-Hwan ; Park, Jung-Seo ; Bae, Choong-Sik ;
Transactions of the Korean Society of Automotive Engineers, volume 15, issue 3, 2007, Pages 10~17
Design of experiments (DOE) technique has been used to design an exhaust heat exchanger to reduce the exhaust gas temperature under high load conditions in a spark-ignition engine. The DOE evaluates the influence and the interaction of a selected eight design parameters of the heat exchanger affecting the cooling performance of the exhaust gas through a limited number of experiments. The heat exchanger was installed between the exhaust manifold and the inlet of the close-coupled catalytic converter (CCC) to reduce thermal aging. To maximize the heat transfer between exhaust gas and coolant, fins were implemented at the inner surface of the heat exchanger. The design parameters consist of the fin geometry (length, thickness, arrangement, and number of fin), coolant direction, heat exchanger wall thickness, and the length of the heat exchanger. The acceptable range of each design parameter is discussed by analyzing the DOE results.
Combustion Characteristics and Durability of Diesel Engines Burning BDF 20
Ryu, Kyung-Hyun ; Oh, Young-Taig ;
Transactions of the Korean Society of Automotive Engineers, volume 15, issue 3, 2007, Pages 18~28
Three diesel engines were fueled with BDF 20, a blend of 80% diesel fuel and 20% biodiesel fuel by volume, and run in excess of 200 h to evaluate their combustion characteristics and durability. The engines used for this study were a 4-cylinder 2476-cc displacement IDI diesel engine(Engine 1), a 4-cylinder l732-cc displacement IDI diesel engine(Engine 2), and a single cylinder 673-cc displacement DI diesel engine(Engine 3). Engine dynamometer testing was performed on each engine at regularly scheduled intervals to monitor the performance and exhaust emissions, which were sampled at 1h intervals for analysis, The peak combustion pressure with BDF 20 increased in Engines 1 and 3 over that measured when burning pure diesel fuel, but that in Engine 2 remained constant. Combustion parameters, such as the maximum combustion pressure and corresponding crank angle, did not change over the long-term dynamometer testing. The BSFC with BDF 20 in Engine 1 was less than that measured with pure diesel fuel. The amount of smoke produced with BDF 20 was less for all engines ; the greatest reduction was observed for Engine 3. The NOx emissions were lower in the IDI engines than the DI engine. The traditional trade-off between smoke and NOx emissions was maintained for BDF 20 fuel for Engines 1 and 3. There was not a big difference in the
emissions for BDF 20, as compared to pure diesel fuel, but more
was exhausted by Engine 1 than by Engines 2 or 3 and less
was exhausted by Engine 1 than by Engines 2 or 3. The engine parts remained clean, except for some carbon attached to the area surrounding the nozzle hole of the DI diesel engine.
Numerical Modeling for Cumulative Impact of Automotive Bumper
Kim, Heon-Young ; Choi, Jong-Gil ; Kim, Jung-Min ; Lee, Kang-Wook ; Yeo, Tae-Jung ;
Transactions of the Korean Society of Automotive Engineers, volume 15, issue 3, 2007, Pages 29~34
Numerical analyses are carried out to evaluate the cumulative impact damage of an automotive front end bumper under the low speed crash events(CMVSS215) by using explicit code. Results of first impact simulation, which are deformed shape, thickness, stress tensors and strain tensors, are used as the initial conditions for a next impact simulation. Between the events, the residual vibration is damped out by using nodal damping, and then recovery after each event is evaluated by several methods, one of which is a springback analysis with implicite finite element analysis code. The coupled analysis scheme for the evaluation of cumulative impact damage is verified through the comparison with test results.
An Experimental Study on Simultaneous Reduction of Smoke and NOx with Biodiesel Fuel in a CRDI Type Diesel Engine
Choi, Seung-Hun ; Oh, Young-Taig ;
Transactions of the Korean Society of Automotive Engineers, volume 15, issue 3, 2007, Pages 35~40
Our environment is faced with serious problems related to the air pollution from automobiles in these days. In particular, the exhaust emissions of diesel engine are recognized main cause which influenced environment strong, In this study, the potential possibility of biodiesel fuel was investigated as an alternative fuel for a naturally aspirated common rail diesel engine. The smoke emission of biodiesel fuel 5vol-%(min. content) was reduced in comparison with diesel fuel, that is, it was reduced approximately 60% at 4000rpm, full load. But, power, torque and brake specific energy consumption didn't have no large differences. But, NOx emission of biodiesel fuel was increased compared with a commercial diesel fuel. Also, the effects of exhaust gas recirculation(EGR) on the characteristics of NOx emission has been investigated. It was found that simultaneous reduction of smoke and NOx was achieved with biodiesel fuel(5vol-%) and cooled EGR method(
) in a common rail diesel engine.
Development of the Lightweight Multi-layered Board with High Stiffness for Automotive Interior Trims
Lee, Kyu-Se ; Lee, Kyung-Sick ;
Transactions of the Korean Society of Automotive Engineers, volume 15, issue 3, 2007, Pages 41~46
Lightweight multi-layered boards with high stiffness for the automotive interior trims were developed, which were composed of a single material. The boards were constructed in the form of substrate/core/substrate with newly developed materials. The materials which have high tensile strength and elongation were selected for the substrate materials, and those which have high compressive strength and low density were selected for the core materials. 25 types of multi-layered boards were fabricated using the selected substrate and core materials. The compatibility with the skin materials, the formability and the tensile strength and flexural strength of the specimens were evaluated. The results show that three types of multi-layered boards(Kenboard/EPP foam/Kenboard, Twintex/PP honeycomb/Twintex, Curv sheet/EPP foam/Curv sheet) are appropriate for the automotive interior trims. Considering the ease of materials supply and the economical aspect, Kenboard/EPP foam/Kenboard is thought to be the most realistic alternative.
A Fundamental Study on Suppressing the Bubbling in the Injector of LPDi Engine by High Pressurization of Fuel
Noh, Ki-Chol ; Lee, Jong-Tai ;
Transactions of the Korean Society of Automotive Engineers, volume 15, issue 3, 2007, Pages 47~53
To suppress the bubble generated in the liquid LPG direct injector is the most important to develop the LPDi engine. It was found in the previous study that bubbling phenomenon in the injector of the LPDi engine is decisively influenced by pressure of fuel and temperature around the injector. Therefore, in this study, the effect on suppressing the bubbling in the LPDi injector by high pressurization of fuel is analyzed and the spray characteristics are also studied. As a result, it is found that the bubbling in the LPDi injector is radically suppressed when the pressure of fuel is over 50MPa. The bubbling is suppressed when the pressure of fuel is over 3MPa if the inserted position of the injector is considered. Also, it is confirmed that the higher the pressure of fuel is the longer spray tip penetration and is the larger spray angle. As the ambient pressure increases, spray tip penetration decreases and spray angle increases due to the increase of drag force.
Knock Characteristic Analysis of Gasoline and LPG Homogeneous Charge Compression Ignition Engine
Yeom, Ki-Tae ; Bae, Choong-Sik ;
Transactions of the Korean Society of Automotive Engineers, volume 15, issue 3, 2007, Pages 54~62
The knock characteristics in an engine were investigated under homogeneous charge compression ignition (HCCI) operation. Liquefied petroleum gas (LPG)and gasoline were used as fuels and injected at the intake port using port fuel injection equipment. Di-methyl ether (DME) was used as an ignition promoter and was injected directly into the cylinder near compression top dead center (TDC). A commercial variable valve timing device was used to control the volumetric efficiency and the amount of internal residual gas. Different intake valve timingsand fuel injection amounts were tested to verify the knock characteristics of the HCCI engine. The ringing intensity (RI) was used to define the intensity of knock according to the operating conditions. The RI of the LPG HCCI engine was lower than that of the gasoline HCCI engine at every experimental condition. The indicated mean effective pressure (IMEP) dropped when the RI was over 0.5 MW/m2and the maximum combustion pressure was over 6.5MPa. There was no significant relationship between RI and fuel type. The RI can be predicted by the crank angle degree (CAD) at 50 CA. Carbon monoxide (CO) and hydrocarbon (HC) emissions were minimized at high RI conditions. The shortest burn duration under low RI was effective in achieving low HC and CO emissions.
System Structure and Reliability Optimization of VVVF Urban Transit Brake System Through Cost Function Construction
Kim, Se-Hoon ; Kim, Hyun-Jung ; Bae, Chul-Ho ; Lee, Jung-Hwan ; Lee, Ho-Yong ; Suh, Myung-Won ;
Transactions of the Korean Society of Automotive Engineers, volume 15, issue 3, 2007, Pages 63~71
During the design phase of a product, reliability and design engineers are called upon to evaluate the reliability of the system, The question of how to meet target reliability for the system arises when estimated reliability or cost is inadequate. This then becomes a problem of reliability allocation and system structure design. This study proposes the optimization methodology to achieve target reliability with minimum cost through construction of the cost function of system. In cost function, total cost means the sum of initial cost, repair cost and maintenance cost. This study constructs optimization problem about system structure design and reliability allocation using cost function. This problem constructed is solved by Multi-island Genetic Algorithm(MIGA), and applies to urban transit brake system. Current brake system of the urban transit is series system. Series system is the simplest and perhaps one of the most common system, but it demands high reliability and maintenance cost because all components must be operating to ensure system operation. Thus this study makes a comparative study by applying k-out-of-n system to brake system. This methodology presented can be a great tool for aiding reliability and design engineers in their decision-makings.
An Experimental Study on Effects of Soot Loading and Mass Flow Rate on Pressure Drop and Heat Transfer in Catalyzed Diesel Particulate Filter
Cho, Yong-Seok ; Noh, Young-Chang ; Park, Young-Joon ; Kim, Duk-Sang ;
Transactions of the Korean Society of Automotive Engineers, volume 15, issue 3, 2007, Pages 72~78
A diesel particulate filter causes progressive increase in back pressure of an exhaust system due to the loading of soot particles. To maintain the pressure drop caused by DPF under proper level, a regeneration process is mandatory when excessive loading of soot is detected in the filter. It is a major reason why the relation between the amount of soot and the pressure drop in a DPF becomes crucial. On the other hand, pressure drop varies with not only the soot loading but also conditions of exhaust gas such as mass flow rate. Therefore, the relation among them becomes complicated. Furthermore, the characteristics of heat transfer in a DPF is another crucial parameter in order for the filter to avoid thermal crack during regeneration period. This study presents characteristics of pressure drop under various conditions of soot loading and mass flow rate in catalyzed diesel particulate filter. This study also shows characteristics of heat transfer in DPF when high temperature gas flows into the filter. Experiments reveal that the soot loading and mass flow rate affect characteristics pressure drop independently. Experiments also indicate that the amount of coating material has little influence on pressure drop with changes in soot loading and mass flow rate. However, increased catalyst coating may lead to the improved heat transfer which is efficiency to reduce thermal stress of the filter.
Vehicle Fuel Economy Improvement by Studies on the Engine Cooling and Ancilliaries System of the Heavy Duty Engine
Lyu, Myung-Seok ;
Transactions of the Korean Society of Automotive Engineers, volume 15, issue 3, 2007, Pages 79~84
Recently it is strongly required to develop the better fuel economy as well as basic power performance based on strict emission legislation. This paper focuses on studies of the engine cooling and ancillaries system among fuel economy factors in the developing stage. Firstly through the analysis of the current specifications, it is assessed whether each components may be designed properly, not overdesigned. Secondly, it is predicted how the fuel economy of each components can be improved. Finally the results are confirmed by vehicle field test equppted with the updatedcomponents. This study found good agreementbetween the prediction and the field test on the vehicle fuel economy improvements of the heavy duty engine vehicle with updated components such as engine cooling and ancilliaries.
Evaluation System for Forward Vehicle Collision Warning System
Yong, Boo-Joong ; Park, Yo-Han ; Yoon, Kyong-Han ; Hwang, Duk-Soo ;
Transactions of the Korean Society of Automotive Engineers, volume 15, issue 3, 2007, Pages 85~90
The main function of the Forward Vehicle Collision Warning System (FVCWS) is to warn a driver when he or she experiences dangerous situations caused by a forward vehicle. Warning distance algorithms under same dangerous circumstances are often various depending on automobile manufacturers and component suppliers. Human factors also should be considered to warn the driver at an adequate warning distance. Therefore, it is necessary to develop a system for evaluating the pertinent warning timing in an identically dangerous situation. The system consists of sensors for measuring speed and acceleration of subject vehicle and target vehicle, controllers to follow the velocity profile properly, and wireless telecommunication equipments for receiving or transmitting the measured data in a real-time. According to actual field tests, it is shown that the developed system is suitable to evaluate warning distance of FVCWS.
A Study on the Evaluation Method of the Operation Stability of a Torque Converter Mounted on Industrial Vehicle
Kim, Beom-Soo ; Lim, Won-Sik ; Cha, Suk-Won ;
Transactions of the Korean Society of Automotive Engineers, volume 15, issue 3, 2007, Pages 91~98
This paper presents the induced mathematical modeling equations for evaluating the operation stability with automatic transmission of heavy duty vehicle. This theoretical approach indicates that linearized governing equations of system can be converted into eigen-value problems. if the eigen-value has positive number, we can predict the engine operating point locates an unstable operating region. To be a stable state, the unstable operating point diverges toward a stable point which is able to maintain uniform velocity. Based on the previous theoretical analysis, we carry out dynamic simulation to show the behavior of engine operating point and torque converter in transient state. As a result of the dynamic simulation, the suggested theoretical method is found to be reasonable for evaluating the operation stability of a torque converter. In addition, the numerical results explain the engine stops and fluctuating phenomenon in reality.
The Study of Flow Rate Performance and Engine Application with LPG Composition Rate for LPi Fuel Supplying System Consisted of Turbine Type Pump
Lim, Mu-Chang ; Myung, Cha-Lee ; Park, Sim-Soo ; Park, Jeong-Nam ; Kim, Sung-Kun ;
Transactions of the Korean Society of Automotive Engineers, volume 15, issue 3, 2007, Pages 99~105
Currently, BLDC fuel pump was applied on LPi vehicle using 3rd fuel supply system as liquified phase LPG injection method had already shown better performance than others. Its cost, however, is rather expensive because of drawbacks such as complicated structure, a fault of localization of system. In this work, demonstration system for a developed turbine type fuel pump to replace BLDC system was setup and investigated. This study results that fuel mass flow rate of turbine type pump and injection performance of injector were better compared to BLDC type. Comparing flow rate of summer LPG with that of winter LPG, the flow rate decreased about 25% using winter LPG. Performance applying turbine type LPi fuel pump to engine is confirmed.
Effect of Chemical Composition on Tensile Property in TRIP-assisted Multiphase Steel for Automobile Structure
Lee, Ki-Yeol ; Bang, Il-Hwan ; Ma, Ah-Ram ; Kim, Young-Sun ;
Transactions of the Korean Society of Automotive Engineers, volume 15, issue 3, 2007, Pages 106~113
The effect of chemical composition on the microstructural change and tensile property in TRIP-assisted steels with different chemical composition was investigated by using SEM, TEM, XRD and UTM. As a result of microscopic observation, the morphology of retained austenite could be identified as two types : a granular type in a steel containing higher sillicon and a film type in a steel having higher carbon. For the case of higher carbon-containing steel with a tensile strength of 860 MPa and a total elongation of 38%, film-typed retained austenite could be observed between lath bainitic ferrite. Actually, metastable retained austenite was a requisite for the good formability, which means that chemical composition plays a significant role in the microstructure and tensile property of TRIP-assisted steels. With respect to tensile property, the steels containing suitable silicon and manganese, respectively, showed a typical TRIP effect in stress-strain curve, while a steel containing higher manganese content exhibited the assimilar behavior shown in dual phase steel.
Strength Design of Driveshafts for Passenger Cars
Jeong, Chang-Hyun ; Jung, Do-Hyun ; Bae, Won-Rak ; Kim, Jin-Yong ; Im, Jong-Soon ;
Transactions of the Korean Society of Automotive Engineers, volume 15, issue 3, 2007, Pages 114~123
We are going to propose equations for stable static and endurance strength design of driveshafts. It is very important to decide the contact normal stress of internal components of CV joints. We can estimate the strength, torque capacity, endurance life of CV joints from contact normal stress by presented equation in this paper. Besides it can be shown the equation for shaft design.
A Study on Electronically Controlled R-134a Heat Pump System for a Fuel Cell Electric Vehicle (FCEV)
Lee, Jun-Kyoung ; Lee, Dong-Hyuk ; Won, Jong-Phil ;
Transactions of the Korean Society of Automotive Engineers, volume 15, issue 3, 2007, Pages 124~132
The main objective of this work is to investigate the characteristics of a heat pump system for fuel cell electric vehicle (FCEV). The present heat pump system adopts an electrically driven compressor running with R134a and uses the heat from the fuel cell stack as the heat source for the exterior heat exchanger. The experimental work has been done with various operating conditions such as different compressor speeds, fuel cell stack coolant temperatures and flow rates. The heating capacity was measured to be from 4 to 10 kW at
ambient temperature, and the outlet temperature of interior heat exchanger was up to
. After 30 seconds from start-up, the system reached a steady state and the heating capacity of 6.8 kW was acquired, and after 90 seconds, the air outlet temperature of interior heat exchanger became
Experimental Study on Firing Test of LPI Engine Using Gasoline Fuel for Improving the Production Process at End of line
Hwang, In-Goo ; Choi, Seong-Won ; Myung, Cha-Lee ; Park, Sim-Soo ; Lee, Jong-Soo ;
Transactions of the Korean Society of Automotive Engineers, volume 15, issue 3, 2007, Pages 133~140
The purpose of this study was to evaluate the effects of gasoline fuel to the LPI engine. Firing test bench was used in order to assess the effect on gasoline-injected LPI engine. Gasoline fuel was supplied into the reverse direction(3-4-2-1 cylinder) at 3.0 bar with commercial gasoline fuel pump. Engine test was performed using the firing test mode at end of line. The deviations of excess air ratio of each cylinder and maximum combustion pressure using gasoline fuel were within 0.1 and
. Engine start time was measured with changing coolant temperature at
, respectively. Residual gasoline volume in the fuel line was measured about 32 cc after firing test and it was less than 2 cc within 10 seconds purging. To simulate the end of line, the residual gasoline in the fuel line was purged during 5 and 10 seconds. Start time of LPI engine with LPG fuel were 0.61 and 0.58 seconds. This work showed that severe problems such as misfiring and liner scuffing were not occurred applying gasoline fuel to LPI engine.
A Study on Development Process of Evaporating Diesel Spray
Yeom, Jeong-Kuk ; Park, Jong-Sang ; Chung, Sung-Sik ; Ha, Jong-Yul ; Kim, Si-Pom ;
Transactions of the Korean Society of Automotive Engineers, volume 15, issue 3, 2007, Pages 141~146
In this study, the effects of change in ambient gas viscosity on spray structure have been investigated in the high temperature and pressure field. To analyze the structure of evaporative diesel spray is important in speculation of mixture formation process. Emissions of diesel engines can be reduced by the control of the mixture formation process. Therefore, this study examines the evaporating spray structure in the constant volume chamber. The viscosity of ambient gas was selected as the experimental parameter, is changed from 21.7 mPa s to 32.1 mPa s by changing in ambient gas temperature. In order to obtain images of the liquid and vapor-phase of injected spray, exciplex fluorescence method was used in this study. The liquid and vapor-phase images were taken with 35mm still camera and CCD camera, respectively. Consequentially, it could be confirmed that the distribution of vapor concentration is more uniform in the case of the ambient gas with high viscosity than in that of the ambient gas with low viscosity.
Aging Characteristics of NOx Storage and Reduction Catalyst for Lean-bum Natural Gas Vehicles
Choi, Byung-Chul ; Lee, Choon-Hee ;
Transactions of the Korean Society of Automotive Engineers, volume 15, issue 3, 2007, Pages 147~152
This study investigates the aging characteristics of NOx storage and reduction(NSR) catalyst on the emission conditions of lean burn natural gas vehicles. We designed various NSR catalysts using by the double-layer washcoat technology to increase of a surface area and a thermal durability performance of the catalysts. The experiments were conducted with 3 kinds of the NSR catalysts, which were manufactured using by a honeycomb cordierite substrate. It was found that Ba is weak in the thermal aging because it has lower melting temperature than that of precious metals (PMs). The suitable loading amount of Ba in this study should be about 42 g/L from the results of the NOx adsorption and the NOx reduction efficiency. The major reason in deactivation of the NSR catalyst is the decrease of the adsorption site owing to the agglomeration and sintering of Ba rather than PM aging by hydrothermal aging. It was confirmed by results of BET, SEM and TEM.
Effect of DPF Regeneration on the Nano Particle Emission of Diesel Passenger Vehicle
Kwon, Sang-Il ; Park, Yong-Hee ; Kim, Jong-Choon ; Lee, Chang-Sik ;
Transactions of the Korean Society of Automotive Engineers, volume 15, issue 3, 2007, Pages 153~159
Nano-Particles are influenced on the environmental protection and human health. The relationships between transient vehicle operation and nano-particle emissions are not well-known, especially for diesel passenger vehicles with DPF. In this study, a diesel passenger vehicle was measured on condition of DPF regeneration and no regeneration on a chassis dynamometer test bench. The particulate matter (PM) emission from this vehicle was measured by its number, size and mass measurement. The mass of the total PM was evaluated with the standard gravimetric measurement method while the total number and size concentrations were measured on a NEDC driving cycle using Condensation Particle Counter (CPC) and EEPS. Total number concentration by CPC was
, which was 20% of result by EEPS. This means about 80% of total particle emission is consist of volatile and small-sized particles(<22nm). During regeneration, particle emission was
, was emitted 400 times compared with the emission before regeneration. As for the particle size of
was emitted mainly, showing peak value of near 40nm in size. This means regeneration decreased the mean size of particles. Regarding regeneration, PM showed no change while the particle number showed about 6 times difference between before and after regeneration. It seems that the regeneration influences on particle number emissions are related to DPF-fill state and filtration efficiency.
Leakage Analysis of the Exhaust Gas for the Engine Exhaust Manifold
Choi, Bok-Lok ;
Transactions of the Korean Society of Automotive Engineers, volume 15, issue 3, 2007, Pages 160~165
Exhaust manifold is generally subjected to thermal cycle loadings ; at hot condition, large compressive plastic deformations are generated, and at cold condition, tensile stresses are remained in highly deformed critical zones. These phenomena originate from that thermal expansions of the runners are restricted by inlet flange connected to the cylinder head, because the former is less stiff than the latter and, the temperature of the inlet flange is lower than that of the runners. Therefore, due to the repetitions of thermal deformation, leakage problems could be occur between inlet flange and cylinder head. In this study, we obtained pressure distributions along gasket bead lines from the finite element analysis and compared to the test results. It shows a good agreement between numerical and experimental results.
An Effects of
Addition on Flame Structure in a Non-premixed Counterflow Flame
Lee, Kee-Man ;
Transactions of the Korean Society of Automotive Engineers, volume 15, issue 3, 2007, Pages 166~173
A numerical study was conducted to have the effect of
addition to fuel on the chemical reaction mechanism with the change of the initial concentration of
and the axial velocity gradient. From this study, it was found that there were two serious effects of
addition on a non-premixed flame ; a diluent effect by the reactive species reduction and chemical effect of the breakdown of
by the third-body collision and thermal dissociation. Especially, the chemical effect was serious at the lower velocity gradient of the axial flow. It was certain that the mole fraction profile of
was deflected and CO was increased with the initial concentration of
. It was also ascertained that the breakdown of
would cause the increasing of CO mole fraction at the reaction region. It was also found that the addition of
did not alter the basic skeleton of
reaction mechanism, but contributed to the formation and destruction of hydrocarbon products such as HCO. The conversion of CO was also suppressed and
played a role of a dilution in the reaction zone at the higher axial velocity gradient.
An Experimental Study on Reductions of Idle Emissions with the Syngas Assist in an SI Engine
Kim, Chang-Gi ; Kang, Kern-Young ; Song, Chun-Sub ; Cho, Young-Seok ;
Transactions of the Korean Society of Automotive Engineers, volume 15, issue 3, 2007, Pages 174~182
Fuel reforming technology for the fuel cell vehicles could be applied to internal combustion engine for the reduction of engine out emissions. Since syngas which is reformed from fossil fuel has hydrogen as a major component, it has abilities to enhance the combustion characteristics with wide flammability and high speed flame propagation. In this study, syngas was added to a gasoline engine to improve combustion stability and exhaust emissions of idle state. Syngas fraction is varied to 0%, 50%, 100% with various ignition timing and excess air ratio. Combustion stability, exhaust emissions, fuel consumption and exhaust gas temperature were measured to investigate the effects of syngas addition on idle performance. Results showed that syngas has ability to widely extend lean operation limit and ignition retard range with dramatical reduction of engine out emissions.
A Study on Heat Exchange Efficiency of EGR Cooler for Diesel Engine to Meet Euro-5 Emission Regulation
Lee, Joon ; Han, Chang-Suk ;
Transactions of the Korean Society of Automotive Engineers, volume 15, issue 3, 2007, Pages 183~188
Recently, diesel engine has been frequently applied to RV, SUV and light duty truck due to the good fuel economy and high thermal efficiency.
and PM, environmental pollution materials are basically produced in diesel combustion process. The most important target in diesel engine research is the development of system to reduce the emissions of
and PM. Cooled EGR system is an effective method for the reduction of
emission and PM emission from a diesel engine and EGR cooler is the key component of the system. This study investigates the EGR cooler of oval gas tubes compared with the EGR cooler of shell & tubes to verify the heat exchange efficiency of cooler by means of engine dynamometer tests, rig performance tests and numerical analyses.