US3934846A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Device to reduce flow induced pressure oscillations in open cavities
Assignee: United States Department of the Air Force
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Filing: 1974-10-08
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Granted: 1976-01-27
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Expires: 1994-10-08
Abstract
Abstract A combined air flow deflector and diffuser assembly including a main flow deflector vane, a deflector base plate mountable adjacent the trailing edge of an open bomb bay or other cavity of a bomber aircraft, aerospace or other vehicle, and a plurality of support pylons interconnected between and supporting the deflector vane in space relation to the base plate immediately behind the bomb bay or other cavity-trailing edge in the path of, and diverting the airstream away from the vehicle body to thereby partially stabilize the turbulent flow at the shield area or airstream flow adjacent the cavity entrance and, simultaneously therewith, induce a substantial decrease of the excessive pressure oscillations that would otherwise occur within the cavity from the air stream flow passing the open cavity. Additional significant reduction primarily in the cavity pressure oscillations results from the formation of a series of divergent, air flow diffusing slots respectively between the base plate and flow deflector vane, and the support pylons and through which a portion of the air stream flows.
Inventors
- 👤 Otto F. Maurer
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 19:07
CPC Classifications
B; B64; B64D; B64D1/00; B64D1/02; B64D1/04
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
370 words
In an aircraft, aerospace or other vehicle having a bomb bay or other cavity for containing weapons or other stores, and door or other enclosure means openable during vehicular operation to expose the open cavity to the relatively fast moving air stream; a combined air flow deflector and diffuser device for reducing excessive pressure oscillations being otherwise induced in and near the open cavity by the inherent unsteady nature of the relatively fast moving air stream flow past the said cavity, as is manifested by the normal considerable inward and outward movement of the said flow relative to the said open cavity when said device is not being utilized; said device comprising; a first, main flow diverter element located in a predetermined spaced relation from the body of said vehicle directly in the path of, and automatically operative to divert a substantial portion of the air stream away from its normal entry into, and thus reducing the intensity of the pressure oscillations both at the entry to, and within the open cavity; second, main flow diverter element-mounting means for attaching said first, flow diverter element in the said predetermined spaced relation from the aircraft fuselage or other vehicular body at a predetermined position in alignment with a location preferably adjacent or substantially adjacent the trailing edge of the open cavity; and third, flow diffuser means comprising divergent slotted means inherently incorporated in said combined air flow diverter and diffuser device between said first, flow diverter element and said mounting means, and further disposed in the path of, and automatically acting to reduce the velocity of the incoming air stream by the diffused flow of a significant, additional portion of the air stream flowing past the open cavity through the said divergent slotted means to thereby further somewhat reduce the inherent turbulence and circulation of air that would otherwise normally occur throughout the interior of the open cavity, and, simultaneously therewith, effecting the substantial elimination of the excessive pressure oscillations resulting at the shield area and within the said open cavity from the inherent and substantial inwardly and outwardly-oriented movements normally tending to occur within, and causing the unsteady flow of the air stream during its movement past the open cavity.
Claim 2
Dependent Claim
370 words
In an aircraft, aerospace or other vehicle having a bomb bay or other cavity for containing weapons or other stores, and door or other enclosure means openable during vehicular operation to expose the open cavity to the relatively fast moving air stream; a combined air flow deflector and diffuser device for reducing excessive pressure oscillations being otherwise induced in and near the open cavity by the inherent unsteady nature of the relatively fast moving air stream flow past the said cavity, as is manifested by the normal considerable inward and outward movement of the said flow relative to the said open cavity when said device is not being utilized; said device comprising; a first, main flow diverter element located in a predetermined spaced relation from the body of said vehicle directly in the path of, and automatically operative to divert a substantial portion of the air stream away from its normal entry into, and thus reducing the intensity of the pressure oscillations both at the entry to, and within the open cavity; second, main flow diverter element-mounting means for attaching said first, flow diverter element in the said predetermined spaced relation from the aircraft fuselage or other vehicular body at a predetermined position in alignment with a location preferably adjacent or substantially adjacent the trailing edge of the open cavity; and third, flow diffuser means comprising divergent slotted means inherently incorporated in said combined air flow diverter and diffuser device between said first, flow diverter element and said mounting means, and further disposed in the path of, and automatically acting to reduce the velocity of the incoming air stream by the diffused flow of a significant, additional portion of the air stream flowing past the open cavity through the said divergent slotted means to thereby further somewhat reduce the inherent turbulence and circulation of air that would otherwise normally occur throughout the interior of the open cavity, and, simultaneously therewith, effecting the substantial elimination of the excessive pressure oscillations resulting at the shield area and within the said open cavity from the inherent and substantial inwardly and outwardly-oriented movements normally tending to occur within, and causing the unsteady flow of the air stream during its movement past the open cavity.
Claim 3
Dependent Claim
33 words
In a combined air flow deflector and diffuser device as in claim 1, and fourth, support means interconnected between said second, main flow diverter element-mounting means and said first, main flow diverter element.
Claim 4
Dependent Claim
38 words
In a combined air flow deflector and diffuser device as in claim 2, wherein said fourth, support means comprises a plurality of separate rigid interconnecting members oppositely attached to said main flow diverter element and said mounting means.
Claim 5
Dependent Claim
25 words
In a combined air flow deflector and diffuser device as in claim 3, wherein said first, main flow diverter element comprises a deflector flap means.
Claim 6
Dependent Claim
36 words
In a combined air flow deflector and diffuser device as in claim 4, wherein said second, main flow diverter element-mounting means comprises a deflector base member directly affixed to the aircraft fuselage or other vehicular body.
Claim 7
Dependent Claim
27 words
In a combined air flow deflector and diffuser device as in claim 3, wherein said first, main flow diverter element comprises an aerodynamically shaped deflector flap member.
Claim 8
Dependent Claim
83 words
In a combined air flow deflector and diffuser device as in claim 6, wherein said fourth, support means comprises a plurality of separate support pylons interconnected between said flow diverter flap member and said deflector base member, and defining the said divergent slotted means of said third, flow diffuser means into a series of separate flow diffuser slots or passages disposed in alternate relation relative to said separate support pylons and between said main flow diverter flap member and said deflector base member.
Claim 9
Dependent Claim
28 words
In a combined air flow deflector and diffuser device as in claim 6, wherein said fourth, support means comprises a plurality of separate and aerodynamically shaped, support pylons.
Claim 10
Dependent Claim
141 words
In a combined air flow deflector and diffuser device as in claim 8, wherein said plurality of support pylons includes a first pair of oppositely-disposed support pylons disposed in streamlined relation to the air stream and interconnected between respective opposite ends of said main flow diverter flap member and said deflector base member; and a second pair of spaced and intermediately-disposed support pylons oriented at a predetermined divergent angle relative to each other and facing in the downstream direction to thereby provide for a centrally-located slot or passage disposed directly in the path of the air stream flow and thus ensuring the automatic substantial and outward expansion both of the volume of the said centrally-located, diffusion slot or passage and the progressively increasing diffusion of the incoming air stream as the latter passes therethrough from its upstream to its downstream side.
Claim 11
Dependent Claim
143 words
In a combined air flow deflector and diffuser device as in claim 9, wherein said deflector base member comprises a mounting plate bent upwardly in the middle a predetermined degree to gradually increase the vertical width and thus the volume of the flow diffuser slots or passages outwardly to both left and right-hand sides of the said third, flow diffuser means and thereby further progressively diffuse the incoming air stream flow as it passes through said diffuser slots or passages to thus provide a somewhat added control means to the positive control technique already being inherently and effectively provided in a relatively large measure by the divergent angle setting of the said second pair of support pylons to the degree of diffusion and simultaneous reduction in the intensity of the pressure oscillations normally occurring at and in the open cavity during vehicular operation.
Claim 12
Dependent Claim
62 words
In a combined air flow deflector and diffuser device as in claim 2, wherein said second, main flow diverter element-mounting means comprises a deflector base member; said fourth, support means comprises a plurality of separate support pylons; and said first, main flow diverter element comprises a deflector flap member rigidly attached to said support pylons and continually exposed in the air stream.
Claim 13
Dependent Claim
100 words
In a combined air flow deflector and diffuser device as in claim 11, wherein said first, main flow diverter element comprises a deflector flap member pivotally or hingedly attached to one end of each of the said support pylons for selective movement between a first, flush or substantially flush relation to the surface of the aircraft fuselage or other vehicular body when in its active position and the cavity doors or other enclosure means are closed, and a second, extended and active position in the path of the air stream when the cavity doors or other enclosure means are opened.
Claim 14
Dependent Claim
176 words
In a combined air flow deflector and diffuser device as in claim 2, wherein said second, main flow diverter element-mounting means comprises a deflector base member disposed at the trailing edge of the cavity at a first, relatively great depth below the surface of the aircraft fuselage or other vehicular body; said fourth, support means comprises a plurality of support pylons rigidly affixed at the inner ends thereof to said deflector base member; and said first, main flow diverter element comprises a deflector flap member rigidly affixed to the outer ends of said support pylons and disposed at a second, relatively small depth with its leading and upper edges respectively arranged at the trailing edge of the cavity and in flush relation to a hinged axis of the said cavity doors or other enclosure means for concealment by the said doors or other enclosure means when in their closed condition, and in continuous and automatic exposure to, and action upon the air stream when the said doors or other enclosure means are in their opened condition.
References Cited (Backward Citations)
US2791387A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1979-01-26 | 1979-07-28 | 1980-01-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-01-26 | 1983-07-28 | 1984-01-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-01-26 | 1987-07-28 | 1988-01-27 | $7700.00 | Window Closed / Lapsed |