AI 中文总结
该研究用二维数值模拟，借助Rothmann-Keller多相格子玻尔兹曼方法，探究完全熔融岩浆海洋中撞击体铁芯碰撞后演化。确定不同尺寸形状撞击体夹带系数，预计千米级撞击体铁-硅酸盐混合不完全，强调岩浆海洋中下部是铁碎片破碎和物质转移关键区。
AI 中文摘要
在本研究中，我们使用一种新颖的Rothmann-Keller多相格子玻尔兹曼方法进行二维数值模拟，研究了完全熔融的岩浆海洋中撞击体铁芯的碰撞后演化。撞击体核心直径从152公里到552公里不等，纵横比从0.75到5。在高达10^4的雷诺数下，模型显示撞击体发生显著变形并逐渐破碎成铁云，直至方法允许的最小尺度（几公里），然后通过湍流分散到岩浆海洋中。我们确定了一系列不同形状的中等撞击体尺寸的夹带系数，发现较大撞击体的夹带系数始终较高。通过外推混合数据，我们预计在真实岩浆海洋中千米级撞击体的铁-硅酸盐混合不完全，这与之前部分平衡的预测定性一致。此外，我们的模型强调岩浆海洋的中下部深度是岩浆海洋中铁碎片进一步破碎和物质转移的关键区域。
英文摘要
In this study, we investigate the post-collisional evolution of an impactor's iron core within a fully molten magma ocean using 2D numerical simulations with a novel Rothmann-Keller multiphase Lattice Boltzmann Method. The impactor's core diameter ranges from $152\;\text{km}$ to $552\;\text{km}$, with aspect ratios from $0.75$ to $5$. At Reynolds numbers up to $10^4$, our models reveal significant deformation and progressive fragmentation of the impactor into an iron cloud down to the smallest scale (several kilometers) that our method allows, which is then dispersed throughout the magma ocean by turbulent flow. We determined entrainment coefficients for a range of intermediate impactor sizes with various shapes, finding that larger impactors consistently exhibit higher entrainment coefficients. By extrapolating our mixing data, we anticipate incomplete iron-silicate mixing for kilometer-scale impactors in a real magma ocean, qualitatively consistent with previous predictions of partial equilibration. Additionally, our models highlight the mid- to lower magma ocean depths as critical zones for further iron fragment breakups and material transfer in the magma ocean.
