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Many models have been established to study the evolution of the bubble dynamics and chemical kinetics within a single acoustic cavitation bubble during its oscillation. The content of the bubble is a gas medium that generates the evolution of a chemical mechanism governed by the internal bubble conditions. These gases are described by a state equation, linking the pressure to the volume, temperature and species amounts, and influencing simultaneously the dynamical, the thermal and the mass variation in the cavitation bubble. The choice of the state equation to apply has then a non-neglected effect on the obtained results. In this paper, a comparative study was conducted through two numerical models based on the same assumptions and the same scheme of chemical reactions, except that the first one uses the ideal gas equation to describe the state of the species, while the second one uses the Van der Waals equation. It was found that though the dynamic of the bubble is not widely affected, the pressure and temperature range are significantly increased when passing from an ideal gas model to a real one. The amounts of chemical products are consequently raised to approximately the double. This observation was more significant for temperature and pressure at low frequency and high acoustic amplitude, while it is noticed that passing from ideal gas based approach to the Van der Waals one increases the free radicals amount mainly under high frequencies. When taking the results of the second model as reference, the relative difference between both results reaches about 60% for maximum attained temperature and 100% for both pressure and free radicals production. 相似文献
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介绍了一种斯特林回热式制冷效应和主动式磁制冷效应耦合的新型制冷循环。循环采用的回热填料钆既是磁制冷循环的磁热材料又是斯特林制冷的回热材料。通过斯特林回热式制冷循环和磁制冷效应的正面耦合叠加获得更优良的制冷效果。同时介绍了一种磁制冷回热器的数值计算模型,本模型是基于控制容积法计算的一维交变流动模型,并对常规回热器内填料能量控制方程进行了修正,考虑了磁性材料磁热效应的影响,添加内热源项。论文计算分析了系统相位角、压力和频率的变化对制冷性能的影响。文中给出的部分模拟结果对后续实验台的改造有一定的借鉴指导作用。 相似文献