Rotorcraft Tail AVC Layout for Main Rotor Wake Vibration
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current vibration suppression systems for rotorcraft fail to effectively address vibrations induced by the main rotor wake on tail surfaces, as they are not designed to counteract aerodynamic effects remotely from the rotor system, leading to incomplete vibration mitigation.
Innovation Solution
The implementation of active vibration control actuators mounted within a specific vibration-affected zone on the extending tail, combined with a hub-mounted vibration suppressor and sensors for feedback, to reduce in-plane loads and vibrations across multiple degrees of freedom.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Object-affected harmful factors
If vibration control actuators are placed remotely from the rotor system to address wake effects, then tail surface vibrations are reduced, but the complexity of the control system increases
Solution Approach 1:
The distributed actuator system serves multiple functions simultaneously: actuators near the main gear box address vibrations from the rotor system and transmission, while actuators on the tail surfaces address wake-induced vibrations. This multi-functional approach allows a single control architecture to handle various vibration sources without requiring separate specialized systems for each location.
Solution Approach 2:
Each distributed actuator unit operates with a degree of independence, sensing and controlling vibrations in its local zone. The feedback from accelerometers at each location is processed to control the corresponding actuators, allowing the system to self-regulate at multiple points without requiring complex centralized coordination for every vibration event.
2Object-affected harmful factors
If multiple distributed actuators are mounted on the tail surfaces, then vibration mitigation is improved, but the weight of the aircraft increases
Solution Approach 1:
Instead of uniformly distributing vibration control throughout the entire aircraft or using a single heavy control system, the solution applies vibration control locally at specific zones where vibrations are most problematic. Actuators are strategically placed on tail surfaces where wake-induced vibrations occur, providing targeted mitigation without adding weight to the entire aircraft structure.
Solution Approach 2:
The system uses multiple lightweight actuator units rather than a single heavy-duty actuator system. Each individual actuator is relatively small and light, designed to handle local vibration control tasks. The cumulative weight of multiple small actuators is less than that of a centralized heavy control system that would need to address all vibration sources from a single location.
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 configuration significantly reduces tail vibrations, achieving levels below baseline systems across various airspeeds, effectively addressing the limitations of existing systems by targeting vibrations induced by the rotor wake.
Implementation Method 1
active vibration control actuators mounted within a specific vibration-affected zone on the extending tail
Implementation Method 2
sensors for feedback
Data Source
Figure 1
Figure 2
Figure 3
AI summary
A vibration suppression system for a rotorcraft having an airframe, a main gear box, a rotor, a hub, a rotor head, and an extending tail including a vertical stabilizer and a stabilator, the vibration suppression system includes one or more active vibration control actuators (AVC) mounted in the extending tail within a vibration affected zone. The vibration affected zone being between about 0% to about 20% of a length of the extending tail measured from a trailing edge of the vertical stabilizer.