在木星内部,区域风的灭
Ulrich R Christensen1, Paula N Wulff1
1Max Planck Institute for Solar System Research, 37077 Göttingen, Germany.
概括
木星强大的区域风受到电导率和行星深处稳定的层次的限制. 一个新的模型揭示了MAC数控制这种灭风的过程,与朱诺任务数据保持一致.
科学领域:
- 行星科学 行星科学
- 流体动力学 流体动力学
- 地质物理学 地质物理学
背景情况:
- 朱诺任务的数据显示,木星强烈的区域风延伸数千公里进入它的内部.
- 这些风在具有显著电导率的深度上被灭,这表明电磁和分层效应.
研究的目的:
- 扩展一个解释木星区域喷气的制动的线性模型.
- 调查稳定分层和电磁效应对风力动力学的作用.
主要方法:
- 利用一个简单的线性化模型,扩展到包括电磁和稳定的分层效应.
- 介绍了MAC数 (磁性,阿基米德数,科里奥利斯数) 作为控制内在流动的关键参数.
- 进行了考虑到密度和电导率变化的计算,在木星的前5600公里内.
主要成果:
- 实际上,MAC号有效地控制了区域风在内密极限的制动.
- 风力下降的模型预测与3D对流模型的相关性很好.
- 稳定层和喷气火区域被限制在接近2000公里的深度.
- 散射向极点增加,解释了更快的赤道喷气.
结论:
- 该研究成功地模拟了木星区域风的灭,使用了分层和电磁力量的组合.
- 稳定层的深度和风灭区域是关键因素,估计约为2,000公里.
- 消散向极点的增加有助于解释喷气速度的度变化.
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