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The behavior of spray injections to turbulent duct flows from a slit injector for direct-injection gasoline engines was investigated using a combination of large eddy simulation (LES) and Lagrangian discrete droplet model (DDM). As a result, diffusion of droplets in stronger turbulent flows was observed at a later stage of the injection. Moreover, we compared calculation and experimental results by generating a pseudo-particle image from the calculation result.

Large eddy simulation based on high-performance computing technique was conducted to investigate the unsteady aerodynamic forces acting on a full-scale heavy duty truck subjected to sudden crosswind. The CFD results were applied to evaluate the effect of the unsteady external forces on a vehicle motion, as a first step toward a more reliable vehicle motion analysis. As the first report, the numerical method was validated on the DNW wind-tunnel data by comparing the time-averaged drag and lateral forces at various yawing angles up to 10 degrees. Then the method was applied to the case when the vehicle goes through the crosswind region. The time series of the aerodynamic forces were acquired and discussed through the visualization of instantaneous flow structures around the vehicle. It was observed that drastic undershooting and overshooting of the yawing moment acts on the vehicle during the rushing in and out process.

In this study, it is purpose to make clear the effect of cavitation phenomenon on the spray atomization. In this report, the cavitation phenomenon inside the nozzle hole was visualized and the pressure measurements along the wall of the nozzle hole were carried out by use of 25-times enlarged acrylic nozzle. For the representatives of regular gasoline, single and two-component fuels were used as a test fuel. In addition, various cavitating flow patterns same as experimental conditions were simulated by use of Barotropic model incorporated in commercial code of Star-CD scheme, and compared with experimental results.

A new method to measure in-cylinder flame propagation and mixture distribution has been developed. The distribution is derived from analyzing the temporal history of flame spectra of CH* and C2*, which are detected by a spark plug type sensor with multi-optical fibers. The validity of this method was confirmed by verifying that the measurement results corresponded with the results of high speed flame visualization and laser induced fluorescence (LIF) measurement. This method was also applied to analysis of cyclic combustion fluctuation on start-up in a direct injection spark ignition (DISI) engine, and its applicability was confirmed.

Roadway departure mitigation systems for helping to avoid and/or mitigate roadway departure collisions have been introduced by several vehicle manufactures in recent years. To support the development and performance evaluation of the roadway departure mitigation systems, a set of commonly seen roadside surrogate objects need to be developed. These objects include grass, curbs, metal guardrail, concrete divider, and traffic barrel/cones. This paper describes how to determine the representative color of these roadside surrogates. 24,762 locations with Google street view images were selected for the color determination of roadside objects. To mitigate the effect of the brightness to the color determination, the images not in good weather, not in bright daylight and under shade were manually eliminated. Then, the RGB values of the roadside objects in the remaining images were extracted.

Low NOx and soot free premixed diesel combustion can be realized by increasing ignition delays in low oxygen atmospheres, as well as the combustion here also depends on fuel ignitability. In this report single intermittent spray combustion with primary reference fuels and a normal heptane-toluene blend fuel under several oxygen concentrations in a constant volume combustion vessel was analyzed with high-speed color video and pressure data. Temperature and KL factor distributions are displayed with a 2-D two-color method. The results show that premixing is promoted with a decrease in oxygen concentration, and the local high temperature regions, above 2200 K, as well as the duration of their appearance decreases with the oxygen concentration. With normal heptane, mild premixed diesel combustion can be realized at 15 vol% oxygen and there is little luminous flame.

The development of a high tech image analog cluster providing good readability is required by today's customer. To satisfy this trend, we have developed a highly unique analog cluster, which features very sharp white lit pointers with evenly illuminated white dials on a black acrylic face. These features are primarily achieved through two new lighting sources: 1. Pointers made from thin, lightweight Cold Cathode Discharge Tubes. This pointer creates very high brightness, regardless of temperature, by enclosing xenon gas in the tube, and was designed into a single side electrode structure. 2. Circular shape Cold Cathode Tube Installed Behind Each Dial Applique. This application creates very bright high quality illumination. In this session, we would like to introduce the construction and system of two new lighting sources for lexus, LS400. This technology provide improved readability.

Besides automobile instrument clusters requiring the high precision and legibility, they must also appeal to the user's fashionable sense. We have been proud of introducing such the cluster, named New Electronic Analogue Meter for the LEXUS LS 400 high quality luxury sedan. This paper describes design features of it as the followings; (1) The acrylic lens with black out effect. (2) Utilizing the cold cathode discharge tubes for pointer and back light of dial applique. (3) The virtual image warning indicators producted on the dial applique of the speedometer or tachometer.

We have developed a new navigation system which utilizes voice synthesis function, and mounted it on the new model. This paper reports the details of the navigation system. The navigation system was developed with the aim of providing a system which is capable of reducing the load on the driver and helping reach the destination smoothly and more safely than the conventional system.

We have developed a new measurement apparatus designed to take orange-peel quality-assessment measurements of paint-finished surfaces on a non-contact basis. This apparatus was developed to determine the relationship between in-line spray-coating conditions and the resulting orange peel surface, and to optimally control/manage the conditions of our existing facilities to ensure the best possible coating results based on the obtained data. The apparatus has been implemented by adopting image analysis, which combines an optical system design based on human inspectors’ visual-checking conditions and a set of straightforward algorithms.

Mixture formation processes of intermittent gas jets were visualized and quantified with high accuracy by a uniquely developed LIF technique (LIFA). Mixture strength inside gas jets was quantified by the fluorescence of iodine in the ambient gas excited by the sheet light of a Nd:YAG laser Two dimensional images of intermittent gas jets of various velocities were continuously recorded with VTR and quantified with high accuracy. The optimum conditions for measurements and accuracy with the LIFA technique were investigated. At the optimum setting of the initial iodine concentration in the ambient gas, accuracies better than 95% were obtained for the ambient gas entrainment ratio or jet concentration. The experimental results show that considerable amounts of ambient gas entrain just under the umbrella-like profile at the top of the jet. The mean jet concentration decreased with decreased nozzle diameter (D), and time elapsed after injection (Δt).

High visibility electronic analog instruments with the blackface lens, lighting up pointers, and back lit dials are used in increasing number for automotive instrumentation. Now, we have developed a new instrument called Optical Space-Vision Instrumentation incorporating the above electronic analog instrument with virtual image by double reflection mechanism. The purpose of this development is to reduce reading time through far-focus and to improve visibility through high contrast. As part of this instrumentation, we also developed a new pointer that uses fluorescent material without a light-emitting element. This paper describes the construction and the engineering technology associated with this instrumentation. According to our test results, this instrument has realized a shorter reading time and higher contrast.

The characteristic of In-Cylinder gas motion of a multivalve engine is compared with a single intake valve engine, which have been predicted by a three-dimensional numerical simulation and flow visualization. The measured intake valve outlet velocity from helical and straight port was adopted as the boundary conditions. The computer graphics technique has been utilized to express the predicted numerical results as moving picture like visualized flow. This flow pattern was compared with the actual flow pattern visualized with metaldehyde as the tracer using the bottom viewed engine, which showed good agreement. The prediction for the multivalve engine showed that the swirl velocity is rapidly reduced by interaction between the flows from the two port, but the turbulence kinetic energy is similar to that in the engines with a single intake valve with helical port.

One-box type vehicles are especially liable to a loss of stability when entering a region of cross-wind. The reasons for this instability were investigated using scale models and by means of a mathematical simulation. Results indicated that yawing moment attains a peak at a precise position of the vehicle relative to the cross-wind. Visualization of the air flow and measurement of the pressure distributions established the cause of the phenomenon. Furthermore a study was conducted into the effects of body shape on stability and the efficacy of various modifications was assessed.

The driving simulator (DS) developed by Toyota Motor Corporation simulates acceleration using translational (XY direction) and tilting motions. However, the driver of the DS may perceive a feeling of rotation generated by the tilting motion, which is not generated in an actual vehicle. If the driver perceives rotation, a vestibulo-ocular reflex (VOR) is generated that results in an unnecessary correction in the driver's gaze. This generates a conflict between the vestibular and visual sensations of the driver and causes motion sickness. Although such motion sickness can be alleviated by reducing the tilting motion of the DS, this has the effect of increasing the amount of XY motion, which has a limited range. Therefore, it is desirable to limit the reduction in the tilting motion of the DS to the specific timing and amount required to alleviate motion sickness. However, the timing and extent of the VOR has yet to be accurately identified.

In recent years Road Departure Mitigation Systems (RDMS) is introduced to the market for avoiding roadway departure collisions. To support the performance testing of the RDMS, the most commonly seen road edge, grass, is studied in this paper for the development of standard surrogate grass. This paper proposes a method for defining the resembling grass color and height features due to significant variations of grass appearances in different seasons, temperatures and environments. Randomly selected Google Street View images with grass road edges are gathered and analyzed. Image processing techniques are deployed to obtain the grass color distributions. The height of the grass is determined by referencing the gathered images with measured grass heights. The representative colors and heights of grass are derived as the specifications of surrogate grass for the standard evaluation of RDMS.