风沙流的综合数值模式
A comprehensive numerical model of wind-blown sand
摘要：
风吹沙，或称“跃变”，将浮尘悬浮到大气中，形成沙丘，并侵蚀地质特征。我们提出了一个全面的稳态跃移的数值模型，在大多数以前的研究相比，可以模拟混合土壤跃移。我们的模型模拟跳跃粒子由于重力，流体阻力，粒子自旋，流体剪切和湍流的运动。此外，该模型明确考虑了由于跃移颗粒的阻力而引起的风的延迟。我们还开发了一个物理为基础的参数化的喷射表面粒子的碰撞跳跃粒子，这与实验结果相匹配。我们的数值模型是第一个再现在撞击阈值（即，跳跃可能的最低剪切速度）和跳跃中的空气动力学粗糙度长度。它还正确地预测了广泛的其他跃移过程，包括风速和粒子质量通量，总高度积分质量通量，和跃移粒子的尺寸分布的配置文件。事实上，我们的模型是第一个重现如此广泛的实验数据的模型。由于我们使用最少数量的经验关系，我们的模型可以很容易地适应于研究各种物理条件下的跳跃，如其他行星上的跳跃，水下的跳跃和跳跃雪。我们的目标是使用我们的模型来开发一个基于物理的参数化粉尘排放用于气候模型。
英文摘要：
Wind-blown sand, or "saltation", ejects dust aerosols into the atmosphere, creates sand dunes, and erodes geological features. We present a comprehensive numerical model of steady-state saltation that, in contrast to most previous studies, can simulate saltation over mixed soils. Our model simulates the motion of saltating particles due to gravity, fluid drag, particle spin, fluid shear, and turbulence. Moreover, the model explicitly accounts for the retardation of the wind due to drag from saltating particles. We also developed a physically-based parameterization of the ejection of surface particles by impacting saltating particles which matches experimental results. Our numerical model is the first to reproduce measurements of the wind shear velocity at the impact threshold (i.e., the lowest shear velocity for which saltation is possible) and of the aerodynamic roughness length in saltation. It also correctly predicts a wide range of other saltation processes, including profiles of the wind speed and particle mass flux, the total height-integrated mass flux, and the size distribution of saltating particles. Indeed, our model is the first to reproduce such a wide range of experimental data. Since we use a minimum number of empirical relations, our model can be easily adapted to study saltation under a variety of physical conditions, such as saltation on other planets, saltation under water, and saltating snow. We aim to use our model to develop a physically-based parameterization of dust emission for use in climate models.
机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。
