摩尔-格雷特泽PDE模型的霍夫分叉与添加噪声的模型
Yiming Meng1, N Sri Namachchivaya1, Nicolas Perkowski2
1Department of Applied Mathematics, Waterloo University, Waterloo, ON Canada.
概括
本研究分析了喷气式发动机压缩机的不稳定性,使用随机局部微分方程 (PDEs). 它开发了减少订单模型,以近似噪音下不稳定边缘,帮助设计更高效的发动机.
科学领域:
- 流体动力学 流体动力学
- 航空航天工程是航空航天工程.
- 非线性动力学是一种非线性动力学.
背景情况:
- 摩尔-格雷特泽部分微分方程 (PDE) 模拟了喷气发动机中的流量和压力.
- 在决定性的PDEs中,Hopf的分叉 (激增,停机) 限制了发动机的运行范围.
- 在随机PDEs中的Hopf分叉并未被很好地理解.
研究的目的:
- 开发近似低维的随机PDEs附近的失败分叉.
- 分析添加噪声对不稳定的影响.
- 允许在不确定性条件下对不稳定性边际进行近似计算.
主要方法:
- 多尺度分析方法. 多尺度分析方法.
- 专注于在快速模式上起作用的添加噪声.
- 缩小维度随机微分方程 (SDEs) 的导数.
主要成果:
- 成功开发了随机 PDE 的低维近似 (SDE).
- 证明了减少的近似含有乘法噪声.
- 提供了一种方法,以在存在不确定性时近似估计不稳定性边际.
结论:
- 开发的SDEs提供了对随机系统中Hopf分叉的见解.
- 接近不稳定边缘可以导致改进的喷气发动机设计.
- 这项工作有助于理解和减轻航空航天应用中的不稳定性.
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