Collaborative Research: CEDAR: High-Resolution Imaging of Instability Dynamics and Breakdown

合作研究：CEDAR：不稳定动力学和击穿的高分辨率成像

• 批准号: 1445783
• 负责人: David Fritts
• 金额: $ 24万
• 依托单位: GLOBAL ATMOSPHERIC TECHNOLOGIES AND SCIENCES, INC.
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-07-15 至 2019-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1445783&HistoricalAwards=false
• 关键词: Collaborative; Research; CEDAR; Resolution; Imaging

This is a 3-year collaborative investigation between The Aerospace Corporation and GATS Inc. to place a new airglow camera at the Andes Lidar Observatory (ALO) in Chile and use those data to study turbulent processes near the mesopause. Turbulent viscosity is a critical unknown parameter in numerical models of the 80 to 100 km altitude region. It is notoriously very difficult to measure. This project will provide a method of measuring this parameter in this important atmospheric region where turbulent viscosity may vary by 3 orders of magnitude. The results of this study will also contribute to a more general understanding of fluid dynamics accompanying flow instabilities. Specifically, this project will utilize the Aerospace Corporation?s new high-resolution infrared camera (AIC2) that uses fast optics and a 2048 x 2048 IR detector to image the OH airglow at 30 m pixel size with a 2 s image cadence. The ALO site also includes a Na wind-temperature lidar and a meteor radar. Data from the AIC2 and the other ALO instruments will be used to investigate the breakdown into turbulence of Kelvin-Helmholtz instabilities (KHIs) and to measure the turbulent viscosity. This new technique will allow characterization of the turbulent viscosity for a variety of background conditions and over daily and seasonal timescales. The measurements will be combined with high-resolution direct numerical simulations to produce the most complete picture to date of KHI breakdown and its evolution into turbulence.

这是航空航天公司和GATS Inc.之间进行的为期3年的合作调查，以在智利安第斯山脉雷达天文台（ALO）放置一个新的气球相机，并使用这些数据来研究中间附近的湍流过程。湍流粘度是80至100 km高度区域的数值模型中的关键未知参数。众所周知，它很难衡量。该项目将提供一种在这个重要的大气区域中测量该参数的方法，在这个重要的大气区域，湍流粘度可能会因3个数量级而变化。这项研究的结果还将有助于对伴随流动不稳定的流体动态有更一般的了解。 具体而言，该项目将利用航空航天公司的新高分辨率红外摄像头（AIC2），该摄像头（AIC2）使用快速光学元件和2048 x 2048 IR探测器以30 m像素大小为OH AIRGLOW图像具有2 s图像的节奏。 ALO部位还包括NA风温激光痛和流星雷达。来自AIC2和其他ALO仪器的数据将用于研究开尔文 - 赫尔莫尔兹稳定性（KHIS）的湍流的分解并测量湍流粘度。这种新技术将允许对各种背景条件以及日常和季节性时间表的湍流粘度进行表征。测量结果将与高分辨率直接数值模拟结合使用，以产生迄今为止KHI崩溃的最完整图像及其演变成湍流。