Plasma Actuator Active Flow Control for Rotorcraft
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Boundary layer separation on aircraft surfaces, such as airfoil and helicopter blades, leads to reduced performance and efficiency due to friction and pressure rise, resulting in momentum and energy loss, which is exacerbated by turbulence and heat conversion.
Innovation Solution
An active flow control system utilizing plasma actuators is integrated into the aircraft, generating plasma near the main rotor apparatus and fuselage to induce local flow speed perturbations and prevent boundary layer separation by converting momentum and energy into thrust.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If boundary layer separation is allowed to occur naturally, then the system structure remains simple, but performance is reduced due to momentum and energy loss
Solution Approach 1:
The patent replaces traditional mechanical flow control devices (such as flaps, vanes, or suction systems) with plasma actuators that use electrohydrodynamic effects. The plasma actuators generate body forces directly in the fluid through ionization and electrostatic forces, eliminating complex mechanical mechanisms while improving boundary layer control and performance.
Solution Approach 2:
The patent changes the physical state of the control system from mechanical to electromagnetic/plasma state. By applying high-voltage electric fields to ionize air and create plasma, the system fundamentally alters the control mechanism from mechanical movement to electromagnetic body forces, achieving better flow control with simpler structure.
2Productivity
If plasma actuators are added to control boundary layer separation, then performance is improved, but device complexity increases
Solution Approach 1:
The patent extracts only the essential functional element (plasma actuator) needed for flow control, eliminating the need for complex mechanical linkages, actuators, and control systems. By taking out just the plasma generation capability, the system achieves effective boundary layer control with minimal added complexity.
Solution Approach 2:
The plasma actuators are designed to be self-regulating to some extent, where the plasma discharge automatically adapts to flow conditions. The electrohydrodynamic body forces are generated directly in the fluid without requiring external mechanical adjustment, allowing the system to self-adjust to varying operating conditions.
3Loss of energy
If plasma actuators are used to prevent boundary layer separation, then energy loss is reduced, but energy consumption increases
Solution Approach 1:
The patent changes the energy input method from mechanical work (moving parts) to electromagnetic energy (plasma discharge). By applying electrical energy to create plasma, the system generates body forces that directly counteract adverse pressure gradients, reducing momentum loss and turbulent energy dissipation, which can be more efficient overall despite the electrical energy input.
Solution Approach 2:
The patent substitutes mechanical energy transfer (through moving flaps or vanes) with electrohydrodynamic body forces. The plasma actuators create distributed body forces throughout the boundary layer, which is more efficient than mechanical systems that rely on surface pressure changes, reducing overall energy loss in the flow.
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
The active flow control system enhances lift-to-drag ratios and reduces drag, thereby improving the overall performance and efficiency of high-speed coaxial rotorcraft by maintaining flow attachment and preventing turbulence.
Implementation Method 1
plasma actuators configured to generate plasma at one or more of the main portion proximate to the hub pylon, the hub pylon, the sail fairing and the aft fuselage section
Data Source
AI summary
An aircraft is provided and includes a fuselage including a top and a tail, a main rotor apparatus disposed at the top of the fuselage, which rotates one or more rotors to generate lift, and an active flow control (AFC) system. The AFC system includes plasma actuators configured to generate plasma at a location adjacent to the main rotor apparatus and/or at the tail of the fuselage.