An Integrated Framework for High-Order Aeroacoustics of Complex Configurations

复杂结构高阶气动声学的集成框架

• 批准号: 1114816
• 负责人: Antony Jameson
• 金额: $ 42.54万
• 依托单位: Stanford University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-10-01 至 2014-09-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1114816&HistoricalAwards=false
• 关键词: Integrated; Framework; Order; Aeroacoustics; Complex

Direct numerical simulation of noise production and propagation remains prohibitively expensive for engineering problems due to resolution requirements. Consequently, hybrid approaches are adopted, which consist of predicting near-field flow quantities via a suitable computational fluid dynamics simulation, and far-field sound radiation by aero-acoustic integral methods, or acoustic analogy formulations. It is critical that the complex flow physics associated with sound generation in the near field is accurately captured by the computational fluid dynamics simulation. Therefore, it is necessary to use a high-order numerical scheme with very low dispersion/dissipation errors. Also, the most significant airframe noise sources are landing gear and high-lift components, such as slats and flaps. The geometric complexity of these components calls for use of numerical methods that can perform well on unstructured grids. The high-order Vincent-Castonguay-Jameson-Huynh (VCJH) schemes recently developed by the principal investigator and colleagues at Stanford University with National Science Foundation funding satisfy both of the aforementioned requirements. In the present work, a state-of-the-art computational framework will be developed for performing aero-acoustics simulations by integrating advanced sub-grid scale (SGS) models for large-eddy simulations (LES) of turbulent flow, and a new Ffowcs Williams-Hawkings (FWH) acoustic analogy formulation for sound propagation, with a graphical processing unit (GPU) enabled high-order VCJH flow solver for unstructured grids. The resulting software will enable the principal investigator and colleagues to undertake high-fidelity large scale aero-acoustics simulations over complex configurations at an affordable cost. The ability to perform such simulations will greatly facilitate design of new aircraft with reduced noise signatures.The future growth of commercial air transportation (currently predicted to triple by the year 2030) may be severely limited by its adverse environmental impacts (both emissions and noise). Noise regulations have become, and will continue to become, increasingly stringent, and noise reduction is now a major consideration in the design of transport aircraft. Although computer simulations currently play a major role in airplane design, their ability to predict noise, and in particular airframe noise (which is the largest component of noise during landing) remains very limited. The principal investigator and his colleagues aim to combine new mathematical and computational techniques to advance the state-of-the-art in noise prediction, and thereby enable design of new, quieter aircraft, with the ultimate target of restricting their noise footprint to within airport perimeters. A successful outcome is significant to the United States economy because commercial aircraft continue to be the largest single export sector.

由于分辨率要求，噪声产生和传播的直接数值模拟对于工程问题来说仍然过于昂贵。因此，采用了混合方法，其中包括通过适当的计算流体动力学模拟来预测近场流量，并通过气动声学积分方法或声学类比公式来预测远场声辐射。计算流体动力学模拟准确捕获与近场声音生成相关的复杂流动物理现象至关重要。因此，有必要使用色散/耗散误差非常低的高阶数值格式。此外，最重要的机身噪声源是起落架和高升力部件，例如缝翼和襟翼。这些组件的几何复杂性要求使用能够在非结构化网格上表现良好的数值方法。斯坦福大学的首席研究员和同事最近在国家科学基金会的资助下开发了高阶 Vincent-Castonguay-Jameson-Huynh (VCJH) 方案，满足上述两个要求。在目前的工作中，将开发一个最先进的计算框架，通过集成用于湍流大涡模拟（LES）的先进子网格尺度（SGS）模型来执行气动声学模拟，以及一种新的用于声音传播的 Ffowcs Williams-Hawkings (FWH) 声学类比公式，具有图形处理单元 (GPU) 支持的用于非结构化网格的高阶 VCJH 流求解器。由此产生的软件将使主要研究人员和同事能够以可承受的成本对复杂的配置进行高保真大规模气动声学模拟。执行此类模拟的能力将极大地促进噪声特征降低的新型飞机的设计。商业航空运输的未来增长（目前预计到 2030 年将增长两倍）可能会因其不利的环境影响（排放和噪声）而受到严重限制。噪声法规已经并将继续变得越来越严格，降噪现已成为运输机设计的主要考虑因素。尽管计算机模拟目前在飞机设计中发挥着重要作用，但它们预测噪声，特别是机身噪声（着陆期间噪声的最大组成部分）的能力仍然非常有限。首席研究员和他的同事们的目标是结合新的数学和计算技术来推进最先进的噪声预测，从而能够设计出更安静的新型飞机，最终目标是将其噪声足迹限制在机场内周长。成功的结果对美国经济意义重大，因为商用飞机仍然是最大的单一出口部门。