320 Abstracts

9535323 Effects of Combustion Chamber Shape on the Collapsing Process of Tumbling Vortices (Investigation by CFD) Shin-ichi Takeuchi (Mitsubishi Motors Corporation), Tomoyuki Wakisaka, Yuzuru Shimamoto (Kyoto University)

Gas flows in the intake ports and cylinders of four-valve spark ignition engines have been numerically analyzed using the GTT method without any turbulence models. It has been shown that the shape of combustion chamber strongly affects the behavior of tumbling vortex during compression stroke. In the cases of flat and concave piston heads, the tumbling vortex is converted to a pair of horizontal vortices near compression TDC. On the other hand, in the cases of convex piston heads, the tumbling vortex is collapsed near compression TDC and many small vortices are generated.

9535332 Calculations of Steady Flow in a Model Intake Port Using Solution Adaptive Grid Yoshihiro Nomura, Youichirou Ohkubo (Toyota Central R&D Labs., Inc.)

A solution based, locally refined adaptive grid technique was devel- oped. Calculations of steady flow in a three dimensional simplified intake port-valve-cylinder model were performed. The calculated discharge co- efficients and the velocity and turbulent distributions for three port curvatures agreed well with experimental results. Reductions of both numerical error and calculation time can be achieved by the solution adaptive grid with a coarse initial grid.

9535341 Oval-Parabola Trajectories (OPT) Model for the Breakup Process of Liquid Droplets Ken Naitoh, Yasuo Takagi (Nissan Re- search Center)

A nonlinear oscillator model, which is called Oval-Parabola Trajecto- ries (OPT) model, is derived in order to describe quantitatively the droplet-air interaction, the breakup process at wall-impingement, and the re-breakup from the edge of wall. The present model can predict the child droplet size and the amount of fuel remaining on wall after wall-inpinge- ment. Then the re-breakup process from wall can be simulated, when the angle of the wall edge becomes larger. The fuel distribution in Sl engine is calculated by using the present model with the numerical air-flow code.

9535350 An Approach to Recognition of the Road Scene in the Fusion of Image Processing and the Laser Radar - Part& The Basic Technology for ASV (Advanced Safety Vehicle) - Kenichi Yamada, Toshio Ito, Kunio Nishioka (Daihatsu Motor Co., Ltd.)

We have been developing the RCAS (Rear-End Collision Avoidance System) which has distance informing function and auto-breaking func- tion. In such a system, recognition of the road scene consisting of the vehicle and the road lane is important technology. To recognize the road scene, the fusion system is more advantageous than the single sensor system. In this paper, we describe the fusion method using a network system. We divided the recognition software into some modules, linked them each other, and decided test function between modules suitable for their characteristics. We tried to correspond the state of the network to the road scene. The experimental results are also reported.

9535369 High Speed Image Processing Hardware for Driving Envi- ronment Recognition M. Ohta, Y. Harata, M. Andoh, A. Watanabe, Y. Ninomiya, T. Kato, H. lto, M. Miyashita (Toyota Central R&D Labs., Inc.), T. Suzuki Y. Nakayama (Toyota Motor Corp.)

We have developed a high speed image processing hardware as a developing tool of image processing algorithm for driving environment recognition. In the hardware, four major functions: string extraction, correlation for template matching, stereo vision and optical flow, are implemented on each original board to realize high speed processing. String extraction board can extract strings on video rate. Within 33 milli-seconds, correlation board is able to process 190 points of template matching, stereo vision board is 128 X 120 points of disparity and optical flow board is 64 X 60 points of flow.

9535378 A Study on Recognition of In-Car Visual Information Hiroyuki Kamiya, Yukinobu Nakamura (Honda R&D Co., Ltd.), Hi- royuki Matsumoto (Japan Traffic Management Technology Association)

This paper deals with a study on in-car visual information provided to drivers. Namba proposes a method to define the amount displayed information by converting the contents of picture into letters and objects. We applied this method to evaluate the information systems, and the results of our study conformed withthe conventional evaluation method which analyzing the display screen visibility by measuring the time to glance at the display. This suggests that the driver selectively chooses information necessary to accomplish his own task rather than recognizing all the information displayed.

9535387 Achievement of Clean Diesel Engines with High Thermal Efficiency Takeyuki Kamimoto (Tokyo Institute of Technology)

Recent technologies such as supercharging, injection rate control and EGR are all aiming at reducing exhaust emissions from Diesel engines without sacrifice of fuel economy. Among them, supercharging pursues lower bulk cylinder gas temperatures as well as the reduced heat loss and pumping work. Injection rate control seems promising for improving the trade-off between perticulates and NOx emissions through ignition delay control and fuel-air mixing enhancement. To achieve cleaner exhaust emissions, development of Diesel fuels with lower sooting tendency and higher cetane numbers is required. Exhaust gas energy recovery systems should also be introduced for better fuel economy.

9535396 A Process of Mixture Formation of Impinging Spray on the Wall in a Hole Type Nozzle Toshitsugu Wakamatsu (Kitami Institute of Technology Graduate School), Hideyuki Tsunemoto, Hiromi lshitani (Kitami Institute of Technology)

To improve the combustion in a direct injection diesel engine, it is important to improve the mixture formation on the combustion chamber wall. In this study, we took sectional photographs of fuel spray on the various impinging walls and measured the volume and the surface area. As a result, it was found that the important factor of mixture formation on the combustion chamber wall is a impinging angle to the wall and the corner radius of impinging wall.

9535404 Numerical analysis of DI Diesel Spray - Spray Shape Analysis of Slit-type Nozzel Hole by KIVA2 - Keiichi Nakagome, Hiroshi Yamamoto, Keiichi Niimura (New ACE Institute Co., Ltd)

Spray formation of slit shaped nozzle hole was analysed by the simulation with KlVA2 code. To simulate the injection of particle from slit shaped nozzle, calculation conditions were changed that fuel particle were spouted from random point within the slit shaped hole area and the maximum spray angles were set individually in the direction of x, y axis of the slit shape. In the case of high density atmosphere, the cross section of spray became circular instead that spray angle was much larger in the direction of perpendicular to the longitudinal axis of slit at very low density atmosphere.

9535413 The Study of the Effects of Chamber Geometry on Flame Behavior in a DI Diesel Engine Zhang Long, Takahiro Ueda, Toshiaki Takatsuki, Katsuhiko Yokota (lsuzu Advanced Engineering Center, Ltd.)

The effects of the combustion chamber Geometry on flame behavior have been investigated in an optically accessible Dl diesel engine. The flame behaviors in three different chamber geometries included the production type were visualized from under the transparent piston crown and from a pseudo-endoscope system. By comparing the velocity distrihu- tion of the flames, which were measured through image processing and analyzing the spreading of the flames over the clearance area for each chamber, the results showed that, (1) the chamber geometry has signifi- cant effect on the flame velocity, the reentrant chamber has shown large flame velocity than the dish chamber, (2) the flame distribution inside and

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outside the chamber has considerably affected by the chamber geometry, the reentrant chamber has prevented the flame from spreading over the clearance, (3) only through achieving larger flame motion and desirable fuel(flame) distribution in the chamber simultaneously can the lower smoke emission be obtained.

9535422 2-D Soot Distribution in D.I. Diesel Engine with Transpar- ent Piston Go Asai, Hirohisa Iida, (Doshisha University Graduate School), Jiro Senda, Hajime Fujimoto (Doshisha University)

2-D distribution of soot in a visualized piston cavity of a D.I. Diesel engine was detected by means of Mie scattering with a thin sheet of Nd:YAG laser. And the distribution of its standard deviation was calcu- lated by statistical image processing, using eight 2-D image taken. As a consequence, following conclusions are drawn: (1) Soots are existing more near on the wall of piston cavity and near the outlet of nozzle than in the other region. (2) Reproducibility of existence of soot is small at the beginning of combustion period and on the contrary, that is high at the last half of combustion duration.

9535431 Voltage Regulator IC Operates in High Temperature Au- tomotive Environment Hitoshi Ishikawa, Hiroyuki Matsumori &sin Seiki Co., Ltd)

More complex electronics in the automobile has caused both the number of Electronic Control Units (ECUs) and the wiring harness between ECUs and mechanical actuators to increase. Attaching the ECU to actuators under the hood solves these two problems: ECU space shortage and increased wiring harness. We developed a voltage regulator IC., complete with power transistors, fabricated with dielectric isolation in order for the IC to operate at the high temperature in the automotive engine compartment.

9535440 Processing of Signals from Sensors for Automobiles by SCF-One Method to Reduce Sampling Noises of SCF Michiru Taka- hashi, Tetsuo Hirano (Nippondenso Co., Ltd)

Switched-capacitor filter (SCF), that has the merits of high precision, high generality, is one of the most efficient circuit in developing filter IC. However, it is the problem that SCF has noises caused by clocks. This paper describes one method to reduce noises caused by sampling (sam- pling noises). The method is as follows: Switches are divided and are driven one by one. Thus on-resistances of switches are controlled by this time lag, 40 percent of sampling noises are reduced by this method.

9535459 Wheel Speed Sensor Applying the Eddy-current Effect Through the High-frequency Modulated Magnetic Field Katsuhiro Teramae (Matsushita Electric Works, Ltd.), Shinobu Nagata (Aisin Seiki Co., Ltd.)

This active-drive wheel speed sensor, developed by the high-frequency magnetic system, enables detection of very slow wheel speeds - hitherto impossible to accomplish with any conventional type of Magnetic Pickup - by applying the eddy-current effect through the high-frequency mag- netic field. The following report presents an analysis of the magnetic circuit which integrates the magnetic-field generating coil with the detec- tion rotor, and the unique circuit system which ensures strength against eccentricity of the wheel rotor and air gap variations, etc.

9535468 Development of Field Navigation System Shigeki Ibara, Masato Minode, Kunio Nishioka (Daihatsu Motor Co., Ltd)

We have developed Field Navigation System which is operated a particular private site such as golf links, an amusement park, and an industrial park. The feature of this system is installation of a control center into a field which communicates with each vehicles. It is able to detect the accurate position of the vehicles and improve user services such as user guidances. This paper describes the configuration of this system, the method of detecting a vehicle position, and the form of communication data and map data for this system.

9535477 On-Board Driving Data Acquisition System, Development and Application - Fundamental Data Acquisition System to incorpo- rate Japanese Driving Conditions within Vehicle Development - Yukihiko Tomita, Ken Yamane, Tobru Koizumi (BMW Japan Corp.)

Accompanying the growing Japanese market for BMW, the demand is increasing to reflect Japanese driving conditions already at the early stage of vehicle development BMW-Japan developed an On-Board Driving Data Acquisition System to describe the driving conditions as quantitative data, so that these conditions can be converted into technical data lo be utilized for the subsequent vehicle development. This report documents the system outline and as an example of the application uses ATM shift program matching to the Japanese market.

9535486 Automatic Functional Test System for ECUs Ryuta Terashima, Noriyoshi Sano, Shigeharu Teshima, Yoshihisa Harata (Toyota Central R&D Labs., Inc.), Mamoru Ban (Aisin Seiki Co., Ltd.)

We have developed an automatic functional test systems for ECUs. In this paper, we propose a new graphical form of specifications of ECUs on the system. In the graphical form, an event which means signal changing is represented by a node, a causality between events is represented by edges, and temporal relations are defined between events without a causality. Our method describing specifications is useful for conventional users because it is possible to describe them incrementally and separately like the conventional specific documents.

9535495 Blue Electroluminescent Displays Masayuki Katayama, Kazuhiko Sugiura, Nobuei Ito, Tadashi Hattori (Nippondenso Co., Ltd.)

Electroluminescence (EL) flat-panel displays provide high display qualities, but have disadvantage that the display colors are limited; so far, only monocromatic, orange-yellow emitting EL displays have been put to practical use. This study suggests that the energy transfer between Ce ions causes the blue component reduction in the luminescence from SrS:Ce EL devices, which usually emits blue-green light. A method is proposed which enhances the blue component, thereby enabling SrS:Ce devices to provide blue light without a filter and to attain high blue luminance.

9535503 Recent Topics on Aerodynamic Noise Masaharu Nishimura (Mitsubishi Heavy Industries Ltd.)

Recent topics on aerodynamic noise are reviewed in this paper. Especially the aerodynamic noise radiated from high speed vehicles is given attention recently. Experimental approach using quiet wind tunnels and computer simulation are both effective for us to understand physical phenomena. But some new ideas are necessary to achieve drastic noise reduction.

9535512 Application of Neural Network to Fluctuating Aerody- namic Noise - Relation between Body Shape and Sensory Test on Driving Condition - Kazunori Oda, Kazuhiko Gotoh, Keiji Sumitani, Syuhma Kitahara, Shigeru Urabe (Toyota Motor Corporation)

Because of improved quietness in automobiles, fluctuating aerody- namic noise has been discerned. Although evaluating and reducing the noise in the early stage of automobile development (planning or pre-pro- totype stage) is expected strongly, it has lots of difficulties in reducing the noise by use of computational fluid dynamics or experimental scheme. So we adopted alternative approach, neural network and succeeded in evalu- ating and reducing the noise. And then we verified the effect of neural network by experiment of flow visualization. As a result we proposed quite a new technique in evaluating and designing automobiles by use of neural network.

9535521 Development of a Numerical Analysis System for Car Aerodynamic Noise Tatsuya Fukushima, Kenji Ono, Hiroyuki Sh- iozawa, Sanae Sato, Ryutaro Himeno (Nissan Motor Co., Ltd.)

The aerodynamic noise caused by an outside door mirror of a car was calculated using Computational Fluid Dynamics. Flows around the car