System and method for distributed active fluidic bleed control

Patent metadata

Field	Value
Publication number	US-10928839-B2
Application number	US-201414173772-A
Country	US
Kind code	B2
Filing date	Feb 5, 2014
Priority date	Feb 6, 2013
Publication date	Feb 23, 2021
Grant date	Feb 23, 2021

Abstract

A system and method for regulating and actuating bleed over a structure exposed in a fluid motion are disclosed. The bleed inlet and outlet are formed on the surface of the structure establishing fluidic communication across surfaces. The disclosed system and method contemplates active control and regulation of the bleed to modify crossflow properties such as, aerodynamic forces, hydrodynamic forces, vorticity, and moments.

First claim

What is claimed is:

1. A distributed active fluid bleed system for regulating a bleed flow to modify parameters of crossflow over surfaces of an airfoil subject to a pressure distribution, the surfaces of the airfoil including an upper surface and a lower surface, the upper and lower surfaces meeting at a leading edge of the airfoil and a trailing edge of the airfoil, the surfaces defining a contiguous internal volume of the airfoil, the distributed active fluid bleed system comprising:
perforations distributed over a majority of the surfaces of the airfoil and in fluidic communication with the contiguous internal volume; and
a perforation mechanism controlling the availability of the perforations to fluidic communication between the contiguous internal volume and outside the airfoil;
wherein the contiguous internal volume is common to all perforations and capable of providing nondeterministic fluidic communication between any configuration of perforations depending on:
an availability of the perforations to fluidic communication via the perforation mechanism; and
the pressure distribution about the airfoil;

wherein each perforation is reconfigurable, and if available to fluidic communication, capable of performing as both an inlet perforation and an outlet perforation at different times;
wherein a perforation performs as an inlet perforation when the perforation is available for fluidic communication and the pressure distribution about the airfoil is such that the perforation is subject to a surface pressure enabling fluidic flow from outside the airfoil into the contiguous internal volume;
wherein a perforation performs as an outlet perforation when the perforation is available for fluidic communication and the pressure distribution about the airfoil is such that the perforation is subject to a surface pressure enabling fluidic flow from the contiguous internal volume to outside the airfoil;
wherein at least a portion of the crossflow enters the contiguous internal volume through at least a portion of the inlet perforations, and exits the contiguous internal volume through at least a portion of the outlet perforations, forming the bleed flow; and
wherein the perforation mechanism comprises:
a non-cyclic sealing system; and
a cyclic sealing system;
wherein at least a portion of the perforations are entirely unavailable to fluidic communication between the contiguous internal volume and outside the airfoil at locations of the non-cyclic sealing system; and
wherein the cyclic sealing system is operable between an open cycle and a closed cycle, wherein at least a portion of the perforations are entirely unavailable to fluidic communication between the contiguous internal volume and outside the airfoil at locations of the cyclic sealing system only when the cyclic sealing system is in the closed cycle.

2. The distributed active fluid bleed system of claim 1 , wherein the airfoil is made of elastic material.

3. The distributed active fluid bleed system of claim 1 , wherein the bleed flow is regulated to modify at least one of a virtual shape and a shape of the airfoil.

4. The distributed active fluid bleed system of claim 1 , wherein the airfoil has a maximum thickness measured perpendicular to a mean camber line of the airfoil; and
wherein perforations are distributed over the entirety of the surfaces of the airfoil from the leading edge to points of maximum thickness located on the upper and lower surfaces of the airfoil.

5. The distributed active fluid bleed system of claim 1 , wherein perforations are distributed over the entirety of the upper surface of the airfoil.

6. The distributed active fluid bleed system of claim 1 , wherein perforations are distributed over the entirety of the leading edge of the airfoil.

7. The distributed active fluid bleed system of claim 1 , wherein perforations are configurable to modify one or more of pressure distribution, aerodynamic forces, hydrodynamic forces, voracity, or moments, of the crossflow about the airfoil when the bleed flow interacts with the crossflow.

8. The distributed active fluid bleed system of claim 1 , wherein the cyclic sealing system comprises a louver hingedly affixed to the lower surface of the airfoil.

9. The distributed active fluid bleed system of claim 1 , wherein the non-cyclic sealing system comprises sealing tape.

10. The distributed active fluid bleed system of claim 1 further comprising:
an actuator operatively coupled to the perforation mechanism; and
a controller for regulating the actuator;
wherein the actuator is configured to move the perforation mechanism between the open cycle, the closed cycle, and positions therebetween.

11. The distributed active fluid bleed system of claim 10 , wherein the controller regulates the actuator time-harmonically.

12. The distributed active fluid bleed system of claim 10 , wherein the actuator is selected from the group consisting of a mechanical actuator, electromechanical actuator, electromagnetic actuator, thermal actuator, and chemical actuator.

13. The distributed active fluid bleed system of claim 10 , wherein the controller regulates the actuator in a time-dependent manner selected from the group consisting of time-periodically, time-harmonically, and using an arbitrary time-dependence.

14. A distributed active fluid bleed system for regulating a bleed flow to modify parameters of crossflow over surfaces of an airfoil subject to a pressure distribution, the surfaces of the airfoil including an upper surface and a lower surface, the upper and lower surfaces meeting at a leading edge of the airfoil and a trailing edge of the airfoil, the surfaces defining a contiguous internal volume of the airfoil, the distributed active fluid bleed system comprising:
perforations distributed over the airfoil and in fluidic communication with the contiguous internal volume;
a perforation mechanism controlling an availability of the perforations to fluidic communication between the contiguous internal volume and outside the airfoil;
an actuator operatively coupled to the perforation mechanism; and
a controller for regulating the actuator;
wherein the contiguous internal volume is common to all perforations and capable of providing nondeterministic fluidic communication between any configuration of perforations depending on:
the availability of the perforations to fluidic communication via the perforation mechanism; and
the pressure distribution about the airfoil;

wherein a perforation is reconfigurable, and if available to fluidic communication, capable of performing as both an inlet perforation and an outlet perforation at different times;
wherein a perforation performs as an inlet perforation when the perforation is available for fluidic communication and the pressure distribution about the airfoil is such that the perforation is subject to a surface pressure enabling fluidic flow from outside the airfoil into the contiguous internal volume;
wherein a perforation performs as an outlet perforation when the perforation is available for fluidic communication and the pressure distribution about the airfoil is such that the perforation is subject to a surface pressure enabling fluidic flow from the contiguous internal volume to outside the airfoil;
wherein at least a portion of the crossflow enters the contiguous internal volume through at least a portion of the inlet perforations, and exits the contiguous internal volume through at least a portion of the outlet perforations, forming the bleed flow;
wherein the perforation mechanism comprises a cyclic sealing system operable between an open cycle and a closed cyc

Assignees

• Georgia Tech Res Inst

Inventors

• Glezer Ari
• Kearney John M

Classifications

• B64C2230/06

  by explicitly adjusting fluid flow, e.g. by using valves, variable aperture or slot areas, variable pump action or variable fluid pressure · CPC title

• Y02T50/10

  Drag reduction · CPC title

• B64C21/025 Primary

  for simultaneous blowing and sucking · CPC title

• G05D7/01 Primary

  without auxiliary power · CPC title

• B64C21/08

  adjustable · CPC title