Investigation of the Rain Process Using Mathematical Models and Observational Data

Trinity College：利用数学模型和观测数据研究降雨过程本项目将提高我们对雨滴生长和相互作用产生大范围雨滴大小的方式的理解。 液滴之间的一些碰撞导致简单的聚结和形成较大的液滴;其他碰撞可能导致碰撞液滴的分裂和较小的卫星液滴的产生。这个问题的数学公式需要的知识的下降速度和不同大小的液滴的碰撞截面，破碎的概率，和卫星液滴的大小分布。 该项目的第一阶段将提供分析近似稀疏现有的实验室数据液滴破碎。 这是必要的概括的方程，描述的碰撞聚结过程中的液滴尺寸分布的演变，包括液滴破碎的影响。 第二阶段将把模式预测与多普勒雷达在自然云层中测量的水滴大小分布进行比较。 如果预报结果与观测结果一致，则可支持在不同环境条件下降水发展的理论计算中使用该模式。

AbstractATM-9812085Brown, Philip S.Trinity CollegeTitle: Investigation of the Rain Process Using Mathematical Models and Observational DataThis project will improve our understanding of the way raindrops grow and interact with each other to produce a broad range of drop sizes. Some collisions between drops lead to simple coalescence and the formation of a larger drop; others may cause breakup of the colliding drops and the production of smaller, satellite droplets. A mathematical formulation of this problem requires knowledge of the fall speeds and collision cross sections of drops of different sizes, the probability of breakup, and the size distribution of the satellite droplets. The first phase of the project will provide analytical approximations to the sparse existing laboratory data on drop breakup. This is essential for generalizing the equations that describe the evolution of the drop-size distribution by the collision-coalescence process to include the effects of drop breakup. The second phase will compare model predictions with the drop-size distributions measured by Doppler radar in natural clouds. If the predictions agree with observations it will support the use of the model in theoretical calculations of rain development under different environmental conditions.