Curved Stabilizer Wing Planform for Rotorcraft Vortex Interaction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional rotorcraft stabilizer wings face significant unsteady aerodynamic loads due to interactions with the main rotor wake, leading to structural stress and reduced handling quality and performance, especially when positioned high on the fin, where unsteady loads are exacerbated at high speeds.
Innovation Solution
A rotorcraft design featuring a stabilizer wing with a quarter chord line having non-zero curvature, arc-shaped leading and trailing edges, and a planform that spreads out the interaction with rotor vortices over time, reducing unsteady aerodynamic loads and allowing for lighter, more space-efficient structural reinforcements.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If the stabilizer wing is placed high on the fin to improve handling quality and performance, then the handling quality and performance are improved, but the unsteady aerodynamic loads caused by rotor wake interaction are significantly increased
Solution Approach 1:
The stabilizer wing employs a curved planform with a curved quarter-chord line instead of a straight configuration. This curvature is specifically designed to reduce the interaction between rotor wake vortices and the wing, thereby decreasing unsteady aerodynamic loads while maintaining the wing's position high on the fin for improved handling quality
2Object-affected harmful factors
If the stabilizer wing is placed at the tail boom position to reduce unsteady aerodynamic loads, then the unsteady aerodynamic loads are reduced, but the static aerodynamic load is comparatively low and the handling quality is reduced
Solution Approach 1:
The curved planform with a curved quarter-chord line is specifically effective at high flight speeds where the rotor wake trajectory passes above a low-positioned stabilizer wing. This allows the wing to be positioned high on the fin for improved handling while the curvature reduces unsteady load interaction at high speeds where it matters most
3Reliability
If the structural stiffness or mass of the stabilizer wing is increased to avoid resonance with rotor wake, then the resonance risk is reduced, but the weight increases and the center of gravity moves to the rear
Solution Approach 1:
The curved planform with a curved quarter-chord line reduces the amplitude of unsteady aerodynamic loads caused by rotor wake interaction. This load reduction allows for a lighter stabilizer wing structure that still maintains sufficient stiffness to avoid resonance with rotor wake excitation frequencies, thereby reducing weight without compromising reliability
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This design significantly reduces unsteady aerodynamic loads, enabling weight savings and improved handling quality and performance by minimizing structural stress and the need for reinforcements, particularly when mounted on the fin, where unsteady loads are most pronounced.
Implementation Method 1
a stabilizer wing that has a planform that reduces the unsteady aerodynamic loads caused on it by the wake of the at least one main rotor
Implementation Method 2
unsteady aerodynamic loads caused on it by the wake of the at least one main rotor
Data Source
AI summary
A rotorcraft, and, more particularly, to a rotorcraft with a fuselage having a center line, at least one main rotor that generates vortices during operation, and a stabilizer wing, whereby the stabilizer wing has a planform that reduces the unsteady aerodynamic loads caused by the wake of the at least one main rotor. In particular, the stabilizer wing may be provided with a left wing tip, a right wing tip, a quarter chord line with a non-zero curvature, such that an interaction between the vortices generated by the at least one main rotor and the quarter chord line is spread out over time, a leading edge that is arc-shaped, and a trailing edge that is arc-shaped.