← Back to Patent Explorer
US4753401A Expired / Lapsed US ⏱️ 0.0 years remaining

Surface, exhibiting reduced flow resistance, of a body over which turbulent flow takes place

Assignee: Deutsches Zentrum für Luft- und Raumfahrt eV
•
Filing: 1985-10-31
•
Granted: 1988-06-28
•
Expires: 2005-10-31
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract The surface of the body is provided with grooves (5), which extend in the flow direction and which are separated from one another by ribs (4) which are constructed to have sharp edges. The surface is composed of a multiplicity of individual elements (3), which have the ribs (4) and grooves (5) on their side facing the flow. The individual elements (3) are disposed relative to one another and/or constructed in such a manner that slits are formed on the side facing the flow between the ribs and grooves. The slits (9) are connected with one another by channels (6) disposed below the surface of the individual elements (3) which faces the flow.

Inventors

  • 👤 Dietrich Bechert

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-24 06:08
CPC Classifications
B; B64; B64C; B64C21/00; B64C21/10; B64C21/02; B64C21/025; B64C2230/00; B64C2230/04; B64C2230/06; B64C2230/20; Y; Y02; Y02T; Y02T50/00; Y02T50/10

Claims Analysis

Total Claims: 11
Claim 1
Independent Claim 125 words
Surface, exhibiting reduced flow resistance, of a body over which turbulent flow takes place, with grooves which extend in the direction of flow and which are separated from one another by ribs which are constructed so as to have sharp edges, characterised in that the surface is composed of a multiplicity of individual elements (3) which have the ribs (4) and grooves (5) on their side facing the flow, that the individual elements (3) are disposed relative to one another and/or constructed in such a manner that slits (9) are formed on the side facing the flow, and that the slits (9) are connected with one another by channels (6A) which are disposed below the surface of the individual elements (3) which faces the flow.
Claim 2
Dependent Claim 125 words
Surface, exhibiting reduced flow resistance, of a body over which turbulent flow takes place, with grooves which extend in the direction of flow and which are separated from one another by ribs which are constructed so as to have sharp edges, characterised in that the surface is composed of a multiplicity of individual elements (3) which have the ribs (4) and grooves (5) on their side facing the flow, that the individual elements (3) are disposed relative to one another and/or constructed in such a manner that slits (9) are formed on the side facing the flow, and that the slits (9) are connected with one another by channels (6A) which are disposed below the surface of the individual elements (3) which faces the flow.
Claim 3
Dependent Claim 28 words
Surface according to claim 1, characterised in that the slits (9) are disposed transversely or obliquely to the direction of flow and are connected with the grooves (5).
Claim 4
Dependent Claim 40 words
Surface according to claim 1 characterized in that the channels (6A/6B) are disposed parallel to the direction of flow as well as transversely thereto whereby fluid communication is provided between all of the grooves of all of the individual elements.
Claim 5
Dependent Claim 58 words
Surface according to claim 1, characterised in that the individual elements (3) are constructed to be rounded off at their front opposed to the direction of flow at the transition between the slits (9) and the ribs (4) or grooves (5), and the ribs (4) end in the direction of flow at the slits (9) in sharp edges.
Claim 6
Dependent Claim 31 words
Surface according to claim 1, characterised in that the width of the grooves (5) and that of the slits (9) are dimensioned to correspond to the thickness of the viscous underlayer.
Claim 7
Dependent Claim 25 words
Surface according to claim 1, characterised in that the channels (6A) are formed by notches disposed on the lower side of the individual elements (3).
Claim 8
Dependent Claim 20 words
Surface according to Claim 1, characterised in that an aspirating or blowing pressure source is connected to the channels (6A).
Claim 9
Dependent Claim 30 words
Surface according to claim 1, characterised in that when there is circulation about the surface with water to the channels an arrangement for the introduction of polymer additives is provided.
Claim 10
Dependent Claim 174 words
A fluid flow surface structure over which turbulent flow takes place comprising a plurality of fluid flow elements of substantially similar size and shape mounted on a surface in juxtaposition with one another to form a substantially uniform fluid flow surface, each of said fluid flow elements including a series of longitudinal ribs usually aligned with the direction of fluid flow and facing the fluid flow, grooves formed between said ribs, the ribs and grooves of each fluid flow element being spaced from the ribs and grooves of adjacent fluid flow elements in the direction of fluid flow and forming slits therebetween said slits extending transversely to the direction of fluid flow, fluid flow channels formed in each fluid flow element and in communication with fluid flow channels of adjacent fluid flow elements and forming a network of fluid flow channels, said fluid flow channels being in communication with the slits formed between adjacent ones of said fluid flow elements, whereby there is free fluid communication through the network of channels and the slits.
Claim 11
Dependent Claim 174 words
A fluid flow surface structure over which turbulent flow takes place comprising a plurality of fluid flow elements of substantially similar size and shape mounted on a surface in juxtaposition with one another to form a substantially uniform fluid flow surface, each of said fluid flow elements including a series of longitudinal ribs usually aligned with the direction of fluid flow and facing the fluid flow, grooves formed between said ribs, the ribs and grooves of each fluid flow element being spaced from the ribs and grooves of adjacent fluid flow elements in the direction of fluid flow and forming slits therebetween said slits extending transversely to the direction of fluid flow, fluid flow channels formed in each fluid flow element and in communication with fluid flow channels of adjacent fluid flow elements and forming a network of fluid flow channels, said fluid flow channels being in communication with the slits formed between adjacent ones of said fluid flow elements, whereby there is free fluid communication through the network of channels and the slits.

References Cited (Backward Citations)

US3184185A Cited
US3451645A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1991-06-28 1991-12-28 1992-06-28 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1995-06-28 1995-12-28 1996-06-28 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1999-06-28 1999-12-28 2000-06-28 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag