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2025 Vol.30, Issue 4 Preview Page

Original Article

DESIGN OF A POD-LSTM MODEL FOR CLOSED-LOOP CONTROL OF SYNTHETIC JET FLOW

합성제트 유동의 폐루프 제어를 위한 POD-LSTM 모델 설계

Y. Son1
,
M.G. Chae1
,
S.H. Park1†
손 예슬1
,
채 민기1
,
박 수형1†
1Department of Aerospace and Mobility Engineering, Konkuk University
1건국대학교 항공우주모빌리티공학과
*Corresponding Author
31 December 2025. pp. 131-151
PDF XML Citation
Abstract

An active flow control framework was designed to suppress flow separation and improve aerodynamic performance at high angles of attack. To enable real-time control of nonlinear unsteady flows, a POD-based reduced-order model was combined with a NARX-LSTM flow estimator. The model predicts dominant flow features from limited pressure-sensor data and reconstructs low-dimensional dynamics efficiently. Sensor optimization was performed through cross-validation to ensure stable and accurate flow reconstruction for the feedback control. Two-dimensional CFD simulations of a NACA0015 airfoil were conducted near stall conditions over a wide range of synthetic jet actuation frequencies. Closed-loop control simulations using a PID controller were performed, and an appropriate range of PID gains was presented to ensure stable and effective actuation response. The results demonstrated that the proposed framework effectively reduced flow separation and thus improved aerodynamic efficiency. This study verifies the capability of data-driven ROM-based surrogate modeling for efficient and accurate active flow control design applicable to future air vehicle systems.

Keywords
Active flow control
Synthetic jet
Reduced order model
Proper orthogonal decomposition
Recurrent neural network
PID controller
키워드
능동 유동 제어
합성 제트
차원 축소 모델
적합 직교 분해
순환 신경망
PID제어기
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Information
  • Publisher :Korean Society for Computational Fluids Engineering
  • Publisher(Ko) :한국전산유체공학회
  • Journal Title :Journal of Computational Fluids Engineering
  • Journal Title(Ko) :한국전산유체공학회지
  • Volume : 30
  • No :4
  • Pages :131-151
  • Received Date : 2025-11-04
  • Revised Date : 2025-12-19
  • Accepted Date : 2025-12-19
  • DOI :https://doi.org/10.6112/kscfe.2025.30.4.131
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