The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Apr. 09, 2002
Filed:
Jul. 28, 2000
Brant H. Maines, Arlington, TX (US);
Lockheed Martin Corporation, Bethesda, MD (US);
Abstract
A controlled passive porosity system includes a lifting device for operation in a multi-phase liquid, the lifting device having a low pressure surface with a plurality of holes and a high pressure surface with a plurality of holes. A common plenum is disposed within the lifting device and allows fluid communication between liquid adjacent the high pressure surface and liquid adjacent the low pressure surface. When cavitation occurs adjacent to the low pressure surface, a series of valves associated with the holes allows selective and localized fluid communication between the surfaces. The fluid communication has the effect of raising the pressure of the liquid in the area of cavitation, thereby eliminating the cavitation. In an alternate embodiment, the lifting device includes a first plenum, a second plenum, and an intermediate fluid passage, the fluid passage fluidly connecting the first plenum and the second plenum. A valve disposed in the fluid passage selectively blocks or allows fluid communication between the high pressure surface and the low pressure surface to eliminate cavitation.