Dynamic characteristics and active control of turbomachinery using dynamic mode decomposition and proper fluctuation excitement

2022 Fiscal Year Final Research Report

• Project/Area Number: 19K04188
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 19010:Fluid engineering-related
• Research Institution: Saitama University
• Principal Investigator: Kang Donghyuk 埼玉大学, 理工学研究科, 准教授 (40610366)
• Project Period (FY): 2019-04-01 – 2023-03-31
• Keywords: 非定常流量 / 動的モード分解 / 特異値分解 / 流れ場の推定 / デジタルツウィン

Outline of Final Research Achievements

We proposed a Venturi-type unsteady flowmeter. The proposal was supported by theoretical analysis, numerical simulations, and experimental verification. This achievement enabled the investigation of the dynamic characteristics of turbo machinery through experiments. Additionally, we measured the dynamic characteristics of a turbofan experimentally and numerically, revealing that the slope of the performance curve during unsteady operation is larger than that during quasi-steady operation.
We also developed a real-time estimation technique for the internal flow field of turbo machinery under quasi-steady conditions. By focusing on the mode decomposition and reconstruction technique of images using singular value decomposition, we devised a mode decomposition and reconstruction technique for flow fields. It was found that the predicted flow field based solely on measurement data closely matched the results obtained from computational fluid dynamics (CFD) simulations.

Free Research Field

流体工学

Academic Significance and Societal Importance of the Research Achievements

非定常ベルヌーイ式を用いて、変動流量装置の開発した。本開発によって変動時の流れの様子を明らかにすることができる。さらに、特異値分解、動的モード分解という手法や時空間FFT・IFFTを用いることによって、ある特定な流れ場の成分を抽出することができた。これによって、複雑流動現象を明らかにすることができた。特に、特異値分解を用いて、ターボ機械のデジタルツウィンができることを示した。