Three-Dimensional Numerical Investigation on the Dynamic Stall Behavior of the Helicopter Rotor Blade at Forward Flight Speeds.
Saved in:
| Title: | Three-Dimensional Numerical Investigation on the Dynamic Stall Behavior of the Helicopter Rotor Blade at Forward Flight Speeds. |
|---|---|
| Authors: | Esfahani, Farid Hosseinzadeh1 (AUTHOR) f.hosseinzadeh@aut.ac.ir, Karimian, S. M. Hossein1 (AUTHOR) hkarim@aut.ac.ir |
| Source: | Arabian Journal for Science & Engineering (Springer Science & Business Media B.V. ). Sep2025, Vol. 50 Issue 17, p14095-14115. 21p. |
| Subjects: | Three-dimensional flow, Aerodynamic load, Turbulence, Helicopters, High-speed aeronautics, Rotors, Vortex methods |
| Abstract: | This study aims to investigate the effect of forward speeds on the flow structure and dynamic stall events of a single rotating blade with pitching motion. Two flight speeds are examined: moderate (µ = 0.3) and high (µ = 0.35) forward flight speeds. To study the three-dimensional flow field, unsteady Reynolds averaged Navier–Stokes (URANS) equations are solved using finite volume discretization and kω-SST turbulence modeling. The present simulations are carefully validated and verified by comparing their results with the experimental data of Caradonna–Tung rotor blade at transonic hover flight and the AH1-G helicopter blade at its maximum forward flight speed. First, the changes in aerodynamic loads and the evolution of various vortex structures on the r/R = 0.778 radial section during the dynamic stall cycle are investigated. Our findings indicate that the stall occurred on the advancing side of both flight speeds due to a shock-induced separation. Development of the stall on the retreating side began with the formation of turbulent separation vortices (TSVs) at the trailing edge region, which then evolved into dynamic stall vortices (DSVs), resulting in the occurrence of multiple dynamic stalls at moderate forward speed. At high forward speed, however, one major stall occurs eventually. Next, the complex three-dimensional flow pattern that emerges on the blade's surface is investigated. This examination illustrates the accumulation of DSVs and the formation of a spanwise vortical structure during pitch-up motion. Also, streamwise vortices (DS-like) are formed on the blade in the pitch-down motion. These phenomena appear at both forward flight speeds. Moreover, simulation findings reveal the dominance of radial flow during the post-stall stage, particularly during pitch-down motion at both flight speeds, significantly affecting vortex evolution at the radial locations of the blade. [ABSTRACT FROM AUTHOR] |
| Copyright of Arabian Journal for Science & Engineering (Springer Science & Business Media B.V. ) is the property of Springer Nature and its content may not be copied or emailed to multiple sites without the copyright holder's express written permission. Additionally, content may not be used with any artificial intelligence tools or machine learning technologies. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.) | |
| Database: | Engineering Source |
|
Full text is not displayed to guests.
Login for full access.
|
|
| Abstract: | This study aims to investigate the effect of forward speeds on the flow structure and dynamic stall events of a single rotating blade with pitching motion. Two flight speeds are examined: moderate (µ = 0.3) and high (µ = 0.35) forward flight speeds. To study the three-dimensional flow field, unsteady Reynolds averaged Navier–Stokes (URANS) equations are solved using finite volume discretization and kω-SST turbulence modeling. The present simulations are carefully validated and verified by comparing their results with the experimental data of Caradonna–Tung rotor blade at transonic hover flight and the AH1-G helicopter blade at its maximum forward flight speed. First, the changes in aerodynamic loads and the evolution of various vortex structures on the r/R = 0.778 radial section during the dynamic stall cycle are investigated. Our findings indicate that the stall occurred on the advancing side of both flight speeds due to a shock-induced separation. Development of the stall on the retreating side began with the formation of turbulent separation vortices (TSVs) at the trailing edge region, which then evolved into dynamic stall vortices (DSVs), resulting in the occurrence of multiple dynamic stalls at moderate forward speed. At high forward speed, however, one major stall occurs eventually. Next, the complex three-dimensional flow pattern that emerges on the blade's surface is investigated. This examination illustrates the accumulation of DSVs and the formation of a spanwise vortical structure during pitch-up motion. Also, streamwise vortices (DS-like) are formed on the blade in the pitch-down motion. These phenomena appear at both forward flight speeds. Moreover, simulation findings reveal the dominance of radial flow during the post-stall stage, particularly during pitch-down motion at both flight speeds, significantly affecting vortex evolution at the radial locations of the blade. [ABSTRACT FROM AUTHOR] |
|---|---|
| ISSN: | 2193567X |
| DOI: | 10.1007/s13369-024-09606-1 |
