Atmospheric and Spray Icings: Formation and Structural Loadings

在建筑物的大气结冰和喷雾结冰领域将开展的工作主要包括在平行分析研究框架内进行的实验研究。主要目标是开发与结冰相关的负荷(结冰重量、空气动力阻力和升力)的改进预报器，以及收集效率和冻结分数的公式，N.将利用爱荷华州水力研究所(IIHR)结冰风洞进行两组实验。第一组将包括对结冰速率、结冰形式和主要结冰类型(釉面、硬质和软质)造成的结构载荷的测量。第二组实验将重点关注：液滴在结冰过程中通过结构元件周围局部流场的轨迹和沉积的动力学；以及与结冰吸积相关的热传递过程。这些测量和对获得的数据的分析将有助于提高对E和n的理解和表述。在进行这项工作时将使用最先进的力传感器和测量以及流动可视化仪器。激光薄片和全息图像处理方法的开创性使用将是对液滴轨迹和沉积测量的重要贡献。私家侦探非常有资格进行这项研究，他可以使用的设施是世界上最好的之一。建议给予为期两年的奖励，但条件是，只有在提交令人满意的调查结果报告和更新的工作计划后，才能给予第三年的支助。

The work to be undertaken in the area of atmospheric and spray icing of structures consists primarily of experimental studies conducted within the framework of parallel analytical studies. The main objective is to develop improved predictors of loading (icing weight, aerodynamic drag and lift) associated with icings, and formulation of collection efficiency, and freezing fractions, n. Two sets of experiments will be conducted using the Iowa Institute of Hydraulic Research (IIHR) Icing Wind Tunnel. The first set will consist of measurements of icing accretion rates, icing forms, and structural loadings due to major icing types (glaze, and hard and soft rime). The second set of experiments will focus attention on: the dynamics of droplet trajectory through, and deposition from the local flow field around a structural element undergoing icing; and the heat transfer processes associated with icing accretion. These measurements and the analysis of the obtained data will help in improving the understanding and formulation E and n. State-of-the-art force transducers and measurement, and flow- visualization instrumentation will he used in carrying out this work. The pioneering use of laser-sheet and holographic methods for image- processing will be an important contribution to droplet trajectories and deposition measurements. The P.I. is highly qualified to perform this research and the facilities at his disposal are among the best in the world. An award for two years is recommended with the proviso that a third year of support can be granted only upon the presentation of a satisfactory report on findings together with an updated workplan.