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This content will become publicly available on August 18, 2026

Title: Numerical analysis of off-axis wind and passive yaw control of an opposing airfoil paired motionless wind energy system
The energy extraction from urban wind at small-to-medium scale is limited due to lower performance and high capital cost of wind energy systems. This study aims to optimize the passive yaw control mechanism of a motionless wind energy system utilizing opposing S1210 airfoils, focusing on enhancing alignment with variable wind directions. A computational fluid dynamics (CFD) framework evaluates five tail vane designs NACA0012, triangular, trapezoidal, arrow, and rounded to assess their aerodynamic performance in generating lift, minimizing drag, and producing turning moments for self-alignment. Results demonstrate that the NACA0012 airfoilshaped vane achieves superior efficiency, balancing high lift (15 % greater than alternatives) and low drag, enabling robust turbine orientation even at wind speeds of 8 m/s. However, off-axis wind angles exceeding 15◦ degrade performance drastically, reducing the coefficient of performance (COP) by 26 % and 81 % at 20◦ and 25◦, respectively, highlighting the importance of passive yaw control. The findings contribute to optimizing the paired airfoil wind energy system for improved performance in urban wind conditions. The study concludes that integrating streamlined tail vanes, such as the NACA0012, significantly enhances the viability of motionless wind turbines for urban deployment, offering a cost-effective solution to harness low-to-medium wind speeds with minimal maintenance.  more » « less
Award ID(s):
1928591
PAR ID:
10639233
Author(s) / Creator(s):
; ; ; ; ; ;
Corporate Creator(s):
Editor(s):
NA
Publisher / Repository:
Elsevier Ltd.
Date Published:
Journal Name:
Energy conversion and management
Edition / Version:
1
Volume:
27
Issue:
101207
ISSN:
2590-1745
Page Range / eLocation ID:
1-8
Subject(s) / Keyword(s):
Passive yaw system Motionless wind energy Urban wind turbine Airfoil pair
Format(s):
Medium: X Size: 5MB Other: pdf
Size(s):
5MB
Sponsoring Org:
National Science Foundation
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