In this paper are presented the results of an experimental study on the chimney effect on natural convection induced airflow for cooling electronic equipment. In order to enhance the natural convective air-cooling capability, the chimney effect increases with inclining the casing. Experiments have been carried out using a ventilated thin electronic equipment-casing model with a plate heater and PCB heater inside. It has inlet and outlet vents on the front and back walls of the casing. This paper presents experimental results of temperature rise inside an electronic casing for various inclinations with different heaters and casing size. The result is the temperature rises of inside casing are gently diminished by the effect of inclination. Otherwise it proposes a good arrangement using Rayleigh and Nusselt number.

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The paper presents a new annealing method and related model experiment for coiled steel plates not only to save energy but to reduce the processing times. The basic idea is to produce the permeable gas flow of high temperature and high pressure in the extremely narrow gaps inherent to the coiled configuration. The experimental results show the time evolution of temperature distribution in coiled steel plate for the parameters of flow rates and inlet temperatures. These results are compared with the numerical analyses to discuss the validities of the basic idea.

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The paper presents an analysis on annealing processes for coiled steel plates not only to save energy but also to reduce the processing times. The basic idea is to produce the permeable gas flow of high temperature and high pressure in the extremely narrow gaps inherent to the coiled configuration. The analytical results show the time evolution of temperature distribution and drastic improvements compared with the conventional heating in muffled type furnace both in energy consumption rates as well as in periods for processes.

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One of the important technologies to design the turbocharger is to reduce the resonance stress of the turbine blade. The resonance stress is greatly influenced by the fluctuating total pressure. In this study, we have tried to examine the relation between fluctuating total pressure and resonance stress and measured the total pressure distribution for circumference angle in a mixed-flow type turbine casing. From measurement data, we calculated the excitation force component of fluctuating total pressure by Fourier analysis. And also we carried out resonance stress measurements for the turbine blade. Through the experiments, it was found that the resonance stress was higher as the fluctuating total pressure was higher.

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