Direct and Large-Eddy Simulation XI
Direct and Large-Eddy Simulation XI
复制标题
直接和大涡模拟 XI
DOI：
10.1007/978-3-030-04915-7_49
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发表时间：
2019
期刊：
影响因子：
--
通讯作者：
Shahab M
中科院分区：
文献类型：
--
作者：
Shahab M
最近制造和控制技术的进步导致了一类新的微型甚至纳米尺寸的飞行器(Micro/Nano UAV)的引入，其飞行条件的特点是中低雷诺数和背景流动不稳定，可能导致严重的空气动力学条件，如大规模分离、动态失速和空气动力学滞后。虽然低雷诺数区域的影响及其对边界层分离和流动非定常的影响已经是许多前人研究的主题，但完全失速条件在过去并没有得到太多的关注。本文采用直接数值模拟的方法，研究了深失速条件下弧形翼型绕流的时空特性。对流动结构和在不同位置采样的速度时间信号的联合分析可以突出存在一些支配流场整体行为的非定常特征。
Recent improvements in manufacturing and control technology have led to the introduction of a new class of micro and even nano sized air vehicles (Micro/Nano UAVs) operating in flight conditions characterized by a medium-to-low Reynolds number and by background flow unsteadiness that may lead to critical aerodynamic conditions such as massive separation, dynamic stall and aerodynamic hysteresis. Although the effect of low Reynolds number regimes and its impact on boundary layer separation and flow unsteadiness have been the subject of many previous studies, fully stalled conditions did not receive much attention in the past. Using Direct Numerical Simulation, the present contribution addresses the spatio-temporal characterisation of the flow around a cambered aerofoil in deeply stalled conditions. A joint analysis of the flow structure and of the velocity time signal sampled in different locations allows to highlight the presence of a number of unsteady features that govern the overall behaviour of the flow field.