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The convective heat transfer of a diesel flame impinging on a flat wall has been studied with a rapid compression machine. Heat flux at the wall as well as the temperature and movement of the flame was measured with varying the impinging distance and angle. The result shows that the local flame temperature increases in the radial direction from the stagnation point due to the progress of combustion, while the heat transfer coefficient decreases in the radial direction, and as a result the distribution of the heat flux on the impinging surface becomes almost uniform.

A new type of bake-hardenable high strength hot-rolled sheet steel was developed, which shows a remarkable increase in tensile strength as well as yield strength after strain age hardening without addition of special elements. The new sheet possesses excellent crashworthiness and high fatigue strength, and also shows good formability, equal to that of conventional high strength sheets. This unique combination of properties makes it possible to reduce the weight of the car body by using thinner gauge material when the new sheet is applied to crash-resistant parts and underbody parts.

Effects of thermal cycle and irradiation on mechanical proreties of Carbon Fiber Reinforced Plastic (CFRP) and adhesives were experimentally investigated. The IM-6/6376, toughened epoxy composite and T800/PMR-15, heat-resistant polyimide composite, and typical nine types of epoxy adhesives were selected as candidate sturctural materials for the future space applications. These materials were subjected to up to 10 MGy irradiation and/or 3000 thermal cycle (-100 °C to 100 °C) which simulates the space environment. After these conditionings, specimens were mechanicaly tested over the temperature range of -100 °C to 100 °C. The results were that the IM-6/6376 was not affected by irradiation and/or thermal cycle. this material showed essentially good overall durability performance in space environments. T-800/PMR-15 was not affected by irradiation this material showed good durability against radiation. The other hands, the adhesives was greatly affected by irradiation and/or thermal cycle.

The formation and oxidation processes of soot particulates in a D. I. diesel engine were investigated under various operating conditions through the measurements of KL factor and flame temperature via the two-color method, whose reliability had been substantiated by a comparative measurement with the direct sampling method. The measured time histories of KL factor and flame temperature show that under all conditions studied soot is promptly formed just after the start of diffusion combustion phase and peaks at around the end of injection, then is oxidized rapidly, followed by the termination of oxidation when the flame temperature drops to 1800 K.

A new technique for measuring velocity in diesel flames has been developed: One of the fluctuating components in a flame is detected at infinitesimally separated two points placed along the flow direction, and the time averaged phase difference between two signals is determined from the cross correlation function calculated over a thousand of cycles. Two kinds of correlation method; one focusing on the radiative intensity fluctuation and the other the temperature fluctuation., have been investigated with a D. I. diesel engine at various flow field, and the characteristics of each method have been made clear.

A model for predicting the spray behavior in an air swirl was developed. High speed Schlieren photographs of a non-evaporating spray in an air swirl were taken with a constant volume vessel which can generate various swirl intensities. A close observation of the photographs revealed that the spread of the spray in the direction perpendicular to the swirl flow is hardly affected by the swirl flow and that the spray is roughly divided into two regions; the main jet region which possesses a major part of momentum and the peripheral region which is torn off the main jet region by the swirl and flows with the same velocity as the local swirl velocity. Basing on this observation a 2-D model proposed by Sinnamon et al. was modified, so that the model was able to predict the spread, trajectory and penetration of a spray in a satisfactory manner.