Patent ID: 6065688
Filing Date: 2000-05-23
Classification: F16K,F23C,F23D

Abstract:
An active control device comprising:an outlet conduit having a first end and a second end, which is capable of fluid flow therethrough between the first and second ends of said outlet conduit with a pressurized fluid entering said outlet conduit through the second end of said outlet conduit and exiting through the first end of said outlet conduit, said pressurized fluid being pressurized within a range which is from about 50 psi to about 100 psi;a piezoelectric wafer having a first side and a second side, with the first side of said piezoelectric wafer abutting the second end of said outlet conduit when said piezoelectric wafer is placed in an equilibrium state, and preventing fluid passage into said outlet conduit;a fluid receptacle forming a chamber, said chamber containing said piezoelectric wafer and the second end of the outlet conduit, said chamber having an inlet opening through which said pressurized fluid can be brought into said chamber; and,means for applying an electric field at a selected frequency to said piezoelectric wafer, wherein the application of said electric field to said piezoelectric wafer distorts said piezoelectric wafer creating a gap between the first side of said piezoelectric wafer and the second end of said outlet conduit allowing said pressurized fluid to pass through said gap to the first end of said outlet conduit to form a plurality of coherent vortices containing said pressurized fluid, said plurality of coherent vortices being formed by said active control device at said selected frequency;the selected frequency of said electric field having a frequency range from about 400 Hertz to about 2000 Hertz;a housing having said chamber contained therein;an upper support ring and a lower support ring suspended inside said chamber by a plurality of support rods that are attached to said housing; andsaid piezoelectric wafer being sandwiched between said upper support ring and said lower support ring around the circumference of said piezoelectric wafer, said piezoelectric wafer being supported by said upper support ring and said lower support ring at a predetermined position relative to said outlet conduit.