Summary: | 碩士 === 雲林科技大學 === 機械工程系碩士班 === 99 === In this paper, a single bubble in a square vertical tube boiling heat transfer factors and detachment of motor behavior research. Square vertical tube were simulated at different heating area, viscosity, boundary conditions, size of the physical phenomena of bubble formation, while the square vertical tube boundary settings are the same. Different heating areas of the nucleation of the bubble and out of time, the bubble formation diameter changes over time, comparing internal overpressure bubble, bubble formation free energy compared to the bubble generation frequency, bubble deformation, thermal and thermal flux relationship, and found that the larger heating surface area of the smaller heat flux, the smaller the bubble departure diameter, from the greater frequency of such phenomena.
The viscosity of each of the different liquids and the size of the container border to observe the bubble from the heating surface after the offset of the central axis, the stability of the flow field, made a considerable viscosity of the liquid Reynolds number, the greater the smaller the bubble, the central axis offset the smaller, the smaller the bubble deformation, the flow chart can be observed that the two sides of the vortex bubble presents a symmetrical phenomenon; when the container the larger the bubble from the boundary after the central axis of the heating surface of the smaller offset by the flow chart can be observed that the two sides of the vortex bubble presents a symmetrical phenomenon.
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