Applying frequency-domain unsteady lifting-line theory to time-domain problems

Bird, H. J.A. and Ramesh, K. (2022) Applying frequency-domain unsteady lifting-line theory to time-domain problems. AIAA Journal, 60(4), pp. 2287-2296. (doi: 10.2514/1.j060898)

Abstract

Frequency-domain unsteady lifting-line theory is better developed than its time-domain counterpart. To take advantage of this, this paper proposes a method to transform time-domain kinematics to the frequency domain, perform a convolution, and then return the results back to the time domain. This paper demonstrates how well-developed frequency-domain methods can be easily applied to time-domain problems, enabling prediction of forces and moments on finite wings undergoing arbitrary kinematics. Results are presented for rectangular wings of various aspect ratios, undergoing pitch and heave kinematics. Computational fluid dynamics is used to test the effectiveness of the method in the Euler and low-Reynolds-number (Re=10,000) regimes. Overall, the proposed method provides fast and reasonably accurate predictions of lift and moment coefficients, particularly in comparison to strip theory, which is commonly used for problems involving arbitrary kinematics.

• Item Type: Articles
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Ramesh, Dr Kiran and Bird, Hugh
• Authors: Bird, H. J.A., and Ramesh, K.
• College/School: College of Science and Engineering > School of Engineering > Autonomous Systems and Connectivity
• Journal Name: AIAA Journal
• Publisher: American Institute of Aeronautics and Astronautics, Inc.
• ISSN: 0001-1452
• ISSN (Online): 1533-385X
• Published Online: 13 December 2021
• Copyright Holders: Copyright © 2021 The Authors
• First Published: First published in AIAA Journal 60(4): 2287-2296
• Publisher Policy: Reproduced in accordance with the publisher copyright policy

Project Code	Award No	Project Name	Principal Investigator	Funder's Name	Funder Ref	Lead Dept
301531		UNSflow: A low-order, open-source solver for problems that involve unsteady and nonlinear fluid dynamics	Kiran Ramesh	Engineering and Physical Sciences Research Council (EPSRC)	EP/R008035/1	ENG - Autonomous Systems & Connectivity