- Email: [email protected]
Comparison of precious metal loading locations in three-way catalysts
436
Abstracts/JSAE Review 17 (1996) 435-458
specific straight intake port improved thermal efficiency. As a result, this power plant achieves excellent drivability, good fuel economy and strong low and mid range torque, which compares favourably with other engines of its type.
was very short and its region was limited to near the front of the engine compartment due to the high pressure and small amount of leak. This trend of the positions of the inflammability limit was very similar to that of experimental results.
9631984 Comparison of Precious Metal Loading Locations in Three-Way Catalysts Marl Yamamoto, Hirohisa Tanaka (Daihatsu Motor Co., Ltd.) We have studied precious metal loading locations in catalysts with the aim of improving conversion efficiency after aging at high temperature in lean atmosphere conditions. In our investigation, we prepared two models of a P t / R h three-way catalyst in which the loading locations of precious metals differed. A model in which Pt and Rh were dispersed throughout the whole of the washcoat showed better durability and more resistance to poisoning by Phosphorous(P) than a model in which Pt and Rh was at the surface of the washcoat. This model maintained finer Pt grain size.
9632037 Improvements and Applications of a Combustion Model of KIVA-II Ishii Yoshinori, Adachi Toshiaki, Zhang Long, Minami Toshitaka, Yokota Katsuhiko (Isuzu Advanced Engineering Center, Ltd.) To achieve a good agreement between calculated and experimental results in engine applications, much work is needed to improve calculation models. This study using KIVA-II is focused on investigating some of the factors which will affect combustion, i.e. the heat release rate. Through this study, it was found that the heat release rate will be changed from one-peak pattern to two-peak pattern by using different combinations of Arrbenius and Magnussen model. Then, as an example of application, the mechanism of combustion using EGR was studied in detail by means of such models.
9631993 Estimation of CCC (Close-Coupled Catalyst) System for Low Emission Vehicles Bynng-Chul Choi (Chonnam National Univ.), Dae-Jung Kim, Geon-Seog Son, Kwi-Young Lee (Institute for Advanced Engineering) A large portion (above 70%) of the engine-out emissions for a typical vehicle occur mainly before the conventional underbody catalytic converter reaches activation temperature. To meet stringent regulations, such as the LEV program and EEC stage 3, the emissions produced during this period must be reduced. One alternative technique is to place a close-coupled catalyst (CCC) near the engine manifold. In this study, the characteristics of CCC were investigated through FTP75 and EEC mode. Test results indicate that Pt/Rh(10/1) catalyst for CCC was much superior in purification of the emissions than the other catalysts. The cold start emissions of the vehicle with CCC system were reduced by more than 75% for HC and by more than 60% for CO in comparison with the base vehicle. 9632000 Analysis of In-Cylinder Flow Field in a Natural Gas Engine - Part 2: Effect of Engine Dimensions - Yukiyoshi Fukano, Haruo Hisaki, Kosuke lsano, Kazuo Tachibana (Osaka Gas Co., Ltd.), Toshikazu Kadota (Osaka Prefecture University) Effect of the engine dimensions on in-cylinder flow field in a natural gas engine was investigated by the laser light sheet method and computer simulation. The following results were obtained: (1) Reverse squish in expansion stroke, which is larger than squish in compression stroke, shifts the direction of swirl. (2) As the piston cavity diameter decreases, squish, swirl and turbulence energy increase. (3) Effect of top clearance on in-cylinder flow is small in our test conditions. 9632019 Numerical Analysis of Pulsatile Flow through Pipe with Different Area Ratios of Nozzle Masaki Endo (Tokyo Metropolitan College of Technology), Junjiro Iwamoto (Tokyo Denki University) A pulsatile flow is experimentally and numerically analyzed through a pipe with a nozzle, the area ratio of the nozzle to the pipe being 1/8, 1/4, 1/3, 1/2 and 3/4. Numerical and experimental results are compared to each other and the boundary conditions are modified for the nozzle given by the extension of the boundary conditions for a three-way junction. The pressure histories are well simulated by a Random-Choice Method with the modified boundary conditions. A good agreement was found between experimental and numerical results far the amplitude of pressure. 9632028 Numerical Simulation on Fuel Fast Leak in Engine Compartment of CNG Vehicles Hano Ryu, Jinji Suzuki (Japan Automobile Research Institute) Three dimensional numerical simulation of fuel fast leak in the engine compartment of CNG vehicles was performed to certify the fire safety for a state of emergency. It was found that the life time of the inflammability limit of CNG fuel
9632046 Computation of the Hollow-Cone Sprays of a High-Pressure Swirl Injector for a Gasoline Direct-Injection Sl Engine Toyosei Yamaucbi (Subaru Research Center Co., Ltd.), Tomoyuki Wakisaka (Kyoto University) The hollow-cone sprays generated by a high-pressure swirl injector were numerically analyzed using the GTT code with spray models. The effects of initial conditions of injection on the spray behavior were investigated by comparing the calculated results with the measured results. On the basis of the PDA measurement data, a way to handle the coarse droplet phenomenon was found. As a result, the structure of a hollow-cone spray was reasonably reproduced by numerical simulation and its change was clarified in terms of fluid dynamics.
9632055 Numerical Simulation of the Generation and Propagation of Shock Wave in the Fuel Injection Pump for Diesel Engine (3rd Report) Masahito Shimada, Takashi Kobayashi (Zexel R&D Center), Yoichiro Matumoto (The University of Tokyo) Generation and propagation of shock waves in the fuel injection pump were investigated numerically. To calculate the generation of shock wave at the end of injection, the movement of plunger and compressibility of liquid were considered in computational code. In the present investigation, the calculation result by analysis code for shock wave generation was used as the inlet shock wave. Furthermore, the effect of bubble size with shock wave propagation on pressure fluctuation was examined. Large size bubbles caused higher peak pressure compared with small size bubbles. 9632064 Study of a Sensor for Fuel Injection Quantity Masanori Amemori, Oliver Berberig, Jun Mizuno, Takashi Kobayashi (Zexel R&D Center) With recent requirements to further improve the emissions and performance of diesel engines, there is a growing need to better control fuel injection quantity and timing, as well as spray properties. In a conventional fuel injection system, we need to measure both control rack position and engine revolution rates to calculate injection quantity. This instrumentation method does not easily monitor the actual injection quantity. To improve measurement accuracy of injection quantity, direct monitoring of fuel flow must be applied. This report describes the performance of a sensor using a micro turbine for measurement of fuel flow under the unsteady flow condition which represents the actual injection property. 9632073 Development of a Single-Shot Injection System for a Fuel Injection System Shoichi Kido, Fumitsugu Yoshizu, Takashi Kobayashi, Toshiyuki Hasegawa (Zexel Corporation) A single-shot injection system for Fuel injection was developed to investigate basic aspects of the spray combustion phenomenon. In this system, a new solenoid three-way valve is used to achieve a constant rail
Abstracts/JSAE Review 17 (1996) 435-458
specific straight intake port improved thermal efficiency. As a result, this power plant achieves excellent drivability, good fuel economy and strong low and mid range torque, which compares favourably with other engines of its type.
was very short and its region was limited to near the front of the engine compartment due to the high pressure and small amount of leak. This trend of the positions of the inflammability limit was very similar to that of experimental results.
9631984 Comparison of Precious Metal Loading Locations in Three-Way Catalysts Marl Yamamoto, Hirohisa Tanaka (Daihatsu Motor Co., Ltd.) We have studied precious metal loading locations in catalysts with the aim of improving conversion efficiency after aging at high temperature in lean atmosphere conditions. In our investigation, we prepared two models of a P t / R h three-way catalyst in which the loading locations of precious metals differed. A model in which Pt and Rh were dispersed throughout the whole of the washcoat showed better durability and more resistance to poisoning by Phosphorous(P) than a model in which Pt and Rh was at the surface of the washcoat. This model maintained finer Pt grain size.
9632037 Improvements and Applications of a Combustion Model of KIVA-II Ishii Yoshinori, Adachi Toshiaki, Zhang Long, Minami Toshitaka, Yokota Katsuhiko (Isuzu Advanced Engineering Center, Ltd.) To achieve a good agreement between calculated and experimental results in engine applications, much work is needed to improve calculation models. This study using KIVA-II is focused on investigating some of the factors which will affect combustion, i.e. the heat release rate. Through this study, it was found that the heat release rate will be changed from one-peak pattern to two-peak pattern by using different combinations of Arrbenius and Magnussen model. Then, as an example of application, the mechanism of combustion using EGR was studied in detail by means of such models.
9631993 Estimation of CCC (Close-Coupled Catalyst) System for Low Emission Vehicles Bynng-Chul Choi (Chonnam National Univ.), Dae-Jung Kim, Geon-Seog Son, Kwi-Young Lee (Institute for Advanced Engineering) A large portion (above 70%) of the engine-out emissions for a typical vehicle occur mainly before the conventional underbody catalytic converter reaches activation temperature. To meet stringent regulations, such as the LEV program and EEC stage 3, the emissions produced during this period must be reduced. One alternative technique is to place a close-coupled catalyst (CCC) near the engine manifold. In this study, the characteristics of CCC were investigated through FTP75 and EEC mode. Test results indicate that Pt/Rh(10/1) catalyst for CCC was much superior in purification of the emissions than the other catalysts. The cold start emissions of the vehicle with CCC system were reduced by more than 75% for HC and by more than 60% for CO in comparison with the base vehicle. 9632000 Analysis of In-Cylinder Flow Field in a Natural Gas Engine - Part 2: Effect of Engine Dimensions - Yukiyoshi Fukano, Haruo Hisaki, Kosuke lsano, Kazuo Tachibana (Osaka Gas Co., Ltd.), Toshikazu Kadota (Osaka Prefecture University) Effect of the engine dimensions on in-cylinder flow field in a natural gas engine was investigated by the laser light sheet method and computer simulation. The following results were obtained: (1) Reverse squish in expansion stroke, which is larger than squish in compression stroke, shifts the direction of swirl. (2) As the piston cavity diameter decreases, squish, swirl and turbulence energy increase. (3) Effect of top clearance on in-cylinder flow is small in our test conditions. 9632019 Numerical Analysis of Pulsatile Flow through Pipe with Different Area Ratios of Nozzle Masaki Endo (Tokyo Metropolitan College of Technology), Junjiro Iwamoto (Tokyo Denki University) A pulsatile flow is experimentally and numerically analyzed through a pipe with a nozzle, the area ratio of the nozzle to the pipe being 1/8, 1/4, 1/3, 1/2 and 3/4. Numerical and experimental results are compared to each other and the boundary conditions are modified for the nozzle given by the extension of the boundary conditions for a three-way junction. The pressure histories are well simulated by a Random-Choice Method with the modified boundary conditions. A good agreement was found between experimental and numerical results far the amplitude of pressure. 9632028 Numerical Simulation on Fuel Fast Leak in Engine Compartment of CNG Vehicles Hano Ryu, Jinji Suzuki (Japan Automobile Research Institute) Three dimensional numerical simulation of fuel fast leak in the engine compartment of CNG vehicles was performed to certify the fire safety for a state of emergency. It was found that the life time of the inflammability limit of CNG fuel
9632046 Computation of the Hollow-Cone Sprays of a High-Pressure Swirl Injector for a Gasoline Direct-Injection Sl Engine Toyosei Yamaucbi (Subaru Research Center Co., Ltd.), Tomoyuki Wakisaka (Kyoto University) The hollow-cone sprays generated by a high-pressure swirl injector were numerically analyzed using the GTT code with spray models. The effects of initial conditions of injection on the spray behavior were investigated by comparing the calculated results with the measured results. On the basis of the PDA measurement data, a way to handle the coarse droplet phenomenon was found. As a result, the structure of a hollow-cone spray was reasonably reproduced by numerical simulation and its change was clarified in terms of fluid dynamics.
9632055 Numerical Simulation of the Generation and Propagation of Shock Wave in the Fuel Injection Pump for Diesel Engine (3rd Report) Masahito Shimada, Takashi Kobayashi (Zexel R&D Center), Yoichiro Matumoto (The University of Tokyo) Generation and propagation of shock waves in the fuel injection pump were investigated numerically. To calculate the generation of shock wave at the end of injection, the movement of plunger and compressibility of liquid were considered in computational code. In the present investigation, the calculation result by analysis code for shock wave generation was used as the inlet shock wave. Furthermore, the effect of bubble size with shock wave propagation on pressure fluctuation was examined. Large size bubbles caused higher peak pressure compared with small size bubbles. 9632064 Study of a Sensor for Fuel Injection Quantity Masanori Amemori, Oliver Berberig, Jun Mizuno, Takashi Kobayashi (Zexel R&D Center) With recent requirements to further improve the emissions and performance of diesel engines, there is a growing need to better control fuel injection quantity and timing, as well as spray properties. In a conventional fuel injection system, we need to measure both control rack position and engine revolution rates to calculate injection quantity. This instrumentation method does not easily monitor the actual injection quantity. To improve measurement accuracy of injection quantity, direct monitoring of fuel flow must be applied. This report describes the performance of a sensor using a micro turbine for measurement of fuel flow under the unsteady flow condition which represents the actual injection property. 9632073 Development of a Single-Shot Injection System for a Fuel Injection System Shoichi Kido, Fumitsugu Yoshizu, Takashi Kobayashi, Toshiyuki Hasegawa (Zexel Corporation) A single-shot injection system for Fuel injection was developed to investigate basic aspects of the spray combustion phenomenon. In this system, a new solenoid three-way valve is used to achieve a constant rail