Collaborative Research: Development of Unmanned Aircraft System for Research in a Severe Storm Environment and Deployment within the VORTEX 2

合作研究：开发用于在严重风暴环境中进行研究的无人机系统并在 VORTEX 2 内进行部署

• 批准号: 0823663
• 负责人: Jerry Straka
• 金额: $ 4.4万
• 依托单位: University of Oklahoma Norman Campus
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-02-01 至 2011-01-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0823663&HistoricalAwards=false
• 关键词: Collaborative; Research; Development; Unmanned; Aircraft

The purpose of this project is to develop and utilize unmanned aircraft systems (UAS) to obtain critical meteorological observations aloft in the rear flank region of supercell thunderstorms. This is a pilot project with the initial emphasis being on the system development and obtaining experience in utilizing such systems in severe storm environments. If the pilot development project is successful, the Principal Investigators intend to participate in the second Verification of the Origins of Rotation in Tornadoes Experiment (VORTEX 2). The investigators will utilize the expertise in unmanned aircraft operations of the University of Colorado to develop a system that is sufficiently safe to obtain a Certificate of Authorization for operation from the Federal Aviation Administration. Observations will be used to evaluate specific hypotheses related to the baroclinic generation of vorticity at the rear of the supercell updraft, and subsequent reorientation of that vorticity into the observed counter-rotating low-level vortices. The cyclonic member of this pair appears often to be the antecedent tornadic vortex. Intellectual Merit Supercell tornadogenesis is the result of a complex series of processes. Evidence suggests that the vorticity in a tornado originates as horizontal vorticity between the supercell updraft and a trailing rear flank downdraft (RFD). The RFD, in turn, appears to be partially the result of small-scale precipitation structures unique to supercells: the hook echo and/or a narrow descending reflectivity core. In some supercells, the vorticity generated between the major vertical drafts is drawn upward in the updraft, leading to arched vortex lines and associated counter-rotating vortices in the rear flank gust front convergence zone. Under certain conditions, that appear to be governed by the degree of negative buoyancy in the RFD, tornadogenesis can occur in the vicinity of the cyclonic member of the counter-rotating pair. Broader Impacts An important goal of this work is that it will contribute to the development of a rapidly-deployable mesoscale and stormscale UAS sensing system. The system will be suitably designed to greatly reduce regulatory hurdles to its future deployment. Important knowledge will be gained on technical and regulatory issues that will allow future deployments of UAS for weather research. Collected observations will improve understanding of RFD buoyancy and tornado cyclone genesis. This information may lead to improvements in the tornado warning process via the diagnosis of rear-flank precipitation morphology and hydrometeor structure using Doppler radars with dual-polarization diversity capability. Further, it is anticipated that RFD buoyancy can be estimated through knowledge of the low-level thermodynamic stratification. Eventually, it is likely that operational meteorologists can make much better discriminations between potentially tornadic and non-tornadic supercells.

该项目的目的是开发和利用无人驾驶飞机系统（UAS），在超级单体雷暴的后翼地区获得关键的高空气象观测。这是一个试点项目，最初的重点是系统开发和获得在严重风暴环境中使用这种系统的经验。如果试点开发项目取得成功，主要研究人员打算参加第二次验证龙卷风实验中旋转的起源（漩涡2）。调查人员将利用科罗拉多大学在无人驾驶飞机操作方面的专业知识，开发一种足够安全的系统，以获得联邦航空管理局的操作授权证书。观测结果将用于评估与超级单体上升气流后部涡度斜压生成相关的具体假设，以及随后将该涡度重新定向为观测到的反向旋转低层涡。这对气旋的成员似乎往往是先行龙卷风涡旋。智力优点超级细胞龙卷风的形成是一系列复杂过程的结果。有证据表明，龙卷风中的涡量起源于超级单体上升气流和后缘下沉气流（RFD）之间的水平涡量。RFD，反过来，似乎是部分的结果，小规模的降水结构独特的超级单体：钩回波和/或一个狭窄的下降反射率的核心。在某些超级单体中，主要垂直气流之间产生的涡量在上升气流中被向上拉，导致在后翼阵风锋会聚区中形成拱形涡线和相关的反向旋转涡。在某些条件下，这似乎是由在RFD的负浮力的程度，龙卷风发生可能发生在附近的反旋转对气旋成员。这项工作的一个重要目标是，它将有助于开发一个可快速部署的中尺度和风暴尺度无人机系统传感系统。该系统将经过适当的设计，以大大减少其未来部署的监管障碍。将获得有关技术和监管问题的重要知识，这些问题将允许未来部署UAS进行天气研究。收集的观测数据将有助于加深对RFD浮力和龙卷风气旋成因的理解。这一信息可能会导致改进龙卷风警报过程中，通过诊断后翼降水形态和水凝物结构，使用多普勒雷达与双极化分集能力。此外，预计RFD浮力可以通过低层热力学分层的知识来估计。最终，业务气象学家可能会更好地区分潜在的龙卷风和非龙卷风超级单体。