CN1730950A - Multiple moveable wall surface drag reduction device for fluid - Google Patents
Multiple moveable wall surface drag reduction device for fluid Download PDFInfo
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- CN1730950A CN1730950A CNA2005100361797A CN200510036179A CN1730950A CN 1730950 A CN1730950 A CN 1730950A CN A2005100361797 A CNA2005100361797 A CN A2005100361797A CN 200510036179 A CN200510036179 A CN 200510036179A CN 1730950 A CN1730950 A CN 1730950A
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- fluid
- movable wall
- drag reduction
- wall
- drag
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B63—SHIPS OR OTHER WATERBORNE VESSELS; RELATED EQUIPMENT
- B63B—SHIPS OR OTHER WATERBORNE VESSELS; EQUIPMENT FOR SHIPPING
- B63B1/00—Hydrodynamic or hydrostatic features of hulls or of hydrofoils
- B63B1/32—Other means for varying the inherent hydrodynamic characteristics of hulls
- B63B1/34—Other means for varying the inherent hydrodynamic characteristics of hulls by reducing surface friction
- B63B1/36—Other means for varying the inherent hydrodynamic characteristics of hulls by reducing surface friction using mechanical means
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15D—FLUID DYNAMICS, i.e. METHODS OR MEANS FOR INFLUENCING THE FLOW OF GASES OR LIQUIDS
- F15D1/00—Influencing flow of fluids
- F15D1/10—Influencing flow of fluids around bodies of solid material
- F15D1/12—Influencing flow of fluids around bodies of solid material by influencing the boundary layer
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02T—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
- Y02T70/00—Maritime or waterways transport
- Y02T70/10—Measures concerning design or construction of watercraft hulls
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- Structures Of Non-Positive Displacement Pumps (AREA)
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Abstract
One kind of fluid friction force reducer is arranged between fluid to be resistance reduced and object surface. It consists of turntable, bearing, rack, movable walls and subsidiary parts. The movable walls around the turntable move with the turntable and have their parts contacting fluid moving with the fluid to reduce resistance to the fluid. Each of the movable walls consists of several layers of wall, and the wall layers can slide freely in fixed direction. Between different wall layers, lubricating fluid is filled, and the internal fluid and external fluid are maintained in balanced pressure. There may be subsidiary movable walls inside the device. The present invention may be used in different fluid resistance reducing fields.
Description
Technical field
The present invention relates to a kind of damping device that reduces the fluid friction resistance.
Background technique
People seek when reducing the fluid resistance method for a long time, and attention was only concentrated in the past and was confined to type body aspect, promptly explored the streamlined aspect of object, and the design of air drag reductions such as present bullet train, guided missile, automobile still is parked in this stage.After founding boundary layer theory, through years development, drag reduction method roughly can be divided into four classes by the different approaches that reduces viscous resistance, one class is the local method that changes the boundary vicinity fluid, as Hovercraft technology, air lubrication technology, its drag reduction power potentiality are considerable, but realize that on whole borders the concrete technology and the technological measure of the displacement of the viscous fluid that viscosity and proportion all differ widely still are difficult to solve fully, popularization is had any problem, and is mainly used in traffic and mechanical engineering field at present.Two classes are by the change of boundary layer temperature and control, or by measure such as air-breathing changing the laminar boundary layer velocity flow profile reducing viscous resistance, this is existing in a large amount of monographs inquires in detail, its drag-reduction effect is limited.Three classes are injected attached wall district drag reduction with the macromolecule thin liquid, can be used for crude oil, water or other fluid drag reduction, but high molecular polymer costs an arm and a leg, and easily lost efficacy, and drag-reduction effect are limited.Four classes are to adopt suitable border material (elastic material) to make the border fully submissive, so that it easily produces dynamic response, vibrate with laminar flow boundary layer T-S wave-wave is moving, and this is grown up by bionics Study, but its drag-reduction effect is still limited.These drag reduction methods all have a large amount of argumentations in various drag reduction mechanics textbooks and monograph.
Summary of the invention
Present various drag reduction methods mostly have limitation and deficiency separately, if any the process engineering complexity, the price that has is expensive, and mostly drag-reduction effect is limited, can only be applied to some field etc., the present invention is then according to proposing a kind of new drag reduction method with the diverse drag principle of present all kinds of drag reduction methods, and provide this method of realization required device in view of the above, this device has that simple structure, fitting operation are convenient, effect significantly, cost economic, and can be applicable to characteristics such as nearly all field fluid drag-reduction.
Generally our the fluid motion state that run in actual engineering application mostly is a turbulent flow, by fluid mechanics knowledge as can be known, when fluid (air, water, crude oil, chemical solution etc.) when a fixed boundary flows through, no matter it is stream or outflow or other forms of motion and the more complicated motion of border form in belonging to, the frictional force formula on itself and border all can finally be expressed as R
f=C
f* 1/2 ρ V
2The form of S, speed is the relative velocity of fluid and interface herein, formula as seen thus, as reduce the relative velocity of fluid and interface, just can make the fluid friction resistance become geometrical progression to successively decrease, but interface is exactly a body surface usually, reduces the relative velocity of fluid and interface, just mean and reduce object or fluid motion speed, this and usage requirement are not inconsistent.If we separate interface with body surface, make its can with the fluid associated movement, a movable wall device is installed between body surface and fluid in other words conj.or perhaps, device can be along with the motion of fluid motion direction with the movable wall of fluid contacting side, after arriving end points, turn to and enter backhaul, from installing interior return to origin, finish a circulation, owing to born the role of interface at this moment with the movable wall of fluid contacting side, laminar boundary layer and laminar flow boundary layer produce at this, it is along with fluid motion direction motion has just reduced relative velocity between it and the fluid, thereby reduced the current gradient value that laminar boundary layer and laminar flow boundary layer are pressed close to boundary, the minimizing of the energy value that causes the minimizing of fluid opposite side interface shear stress and directly disperse by viscosity, just surface friction drag reduces, because install with object in the force analysis and can regard an integral body as this moment, fluid is exactly that fluid resistance to object reduces to the minimizing of movable wall resistance, object convection cell resistance reduces in other words, and the relative movement state of object and fluid and uninfluenced, the drag reduction process is just accused and is finished.
Realize that this method goes to implement with device; shown in Figure 1 is exactly a simple movable wall damping device; form by rotating cylinder (containing the rotating cylinder bearing) (1), rotating cylinder support (2), movable wall (3), seal arrangement (4), protecting sheathing (5); rotating cylinder and bearing are positioned on the support; be fixed on the shell with support; movable wall can be a mantle; or form by the conveyor belt transformation of the way; movable wall twines and is overlying on the rotating cylinder; can move with rotating cylinder, the chamber 1 (8) that is surrounded, and chamber 2 (9), can carry out motive sealing design and charge into the lubricity fluid.Below we verify the drag reduction working principle of movable wall system in conjunction with this device.
Suppose area be A certain under water fixed wall need carry out drag reduction, water velocity is V, then this moment, wall suffered current frictional force size was C
f* 1/2 ρ V
2A, power loss is C
f* 1/2 ρ V
3A.
Now device shown in Figure 1 is positioned on fixed wall surface under water, for ignore resistance that rotating cylinder bearing resistance, movable wall twine etc. for simplicity temporarily on rotating cylinder, filling fluid in the device also is water, and then movable wall will move under the current frictional force drives, and its movement velocity is V when establishing state of equilibrium
1, then to its carry out force analysis as can be known top current driving force equate i.e. C with three the suffered current frictional force of face sums of movable wall at chamber 1 and chamber 2
f* 1/2 ρ (V-V
1)
2A=3C
f* 1/2 ρ V
1 2A can solve V
1≈ 0.366V, then can get the suffered resistance of top current is C
f* 1/2 ρ V
2* 0.634
2=0.402C
f* 1/2 ρ V
2, power loss is 0.402C
f* 1/2 ρ V
3A, the value before the drag reduction, visible removable wall mask drag reduction effect.
We see in above-mentioned proof procedure, fill the surface friction drag of fluid in the chamber 2 that chamber 1 that the inner moving running resistance of movable wall device mainly surrounds from the movable wall inboard and movable wall outside backhaul part and device inwall surround, though in theory can be with chamber 1, chamber 2 is evacuated, thereby eliminate internal drag such as contactless forces such as magnetic suspension force opposing hydrodynamic pressure with other, but obviously be unpractical at present in actual engineering application, to charge into coefficient of viscosity little so the practice of reality is still, the lubricated fluid of using that density is light, fluid can arrange that in chamber 2 movable wall gives drag reduction to the movable wall resistance in the chamber 2, promptly arrange dependent activity wall system (11), this system and the main movable wall system (10) of service for it form basically identical, if still can not meet the demands, then in chamber 2 positions of dependent activity wall system (11), arrange sub-dependent activity wall system (12) again, principle is till reaching requirement according to this, (main movable wall system is meant movable wall and has been contacted the interface effect by drag reducing fluid and carried out that part of system of main anti-drag function that its movable wall also claims the active movement wall) as schematically shown in Figure 3.Equally, fluid can be arranged dependent activity wall system (11) to the resistance of movable wall inboard in chamber 1, still can not meet the demands and then arrange sub-subordinate wall activity system (12) again, and its drag reduction mechanism is similar, as schematically shown in Figure 4.
For understanding the drag-reduction effect of multiple movable wall, existing is that example is verified with the flywheel drag reduction.
As shown in Figure 2, cylindric flywheel (6) at full speed rotates, its periphery is with n the concentric firm matter cylinder of thin-walled as multiple movable wall device, suppose that we put aside the influence of flywheel and each thin walled cylinder end, also ignore the influence of cylinder thickness and spacing and establish flywheel and the long-pending S that is of each layer cylinder inner and outer surface, then obviously each layer cylinder can generate the velocity gradient of successively decreasing successively from inside to outside, and the relative velocity when establishing state of equilibrium between every layer is respectively Δ V
1, Δ V
2, Δ V
3Δ V
n, specific gravity is ρ between each cylinder.
Get m layer cylinder and make force analysis, be subjected to two power effects, a driving force that is interior side liquid to it, size is C
f* 1/2 ρ Δ V
m 2S is the resistance of outer side liquid to it on another, and size is C
f* 1/2 ρ Δ V
M+1 2S, two power equal and opposite in directions, direction is opposite, can derive Δ V
m=V
M+1, all can derive such conclusion to each cylinder equally, also just can draw each layer relative velocity and be V/n, the suffered fluid friction power of flywheel is C so as can be known
f* 1/2 ρ S * (V/n)
2=1/n
2* C
f* 1/2 ρ V
2S, power loss is 1/n
2C
f* 1/2 ρ V
3S that is to say that the suffered surface friction drag of drag reduction rear flywheel and power loss are original 1/n in theory
2, such drag-reduction effect is that other any drag reduction method is too far behind to catch up at present.As seen multilayer wall combination is V with a speed the motion of a plurality of speed much smaller than V resolved in motion, though latter's speed sum still equals V, but resistance and energy sum are much smaller than the former, this is the main cause that movable wall adopts multilayer build-up, also be understood to every superimposed one deck individual layer wall just more than many straton dependent activity wall systems, and omitted members such as rotating cylinder and support.Each individual layer movable wall is difficult for fixedly relative position and produces contact friction in flexible movable wall, the technical measures that the present invention takes are the positioning convex strips that cover self lubricating material outside each individual layer movable wall is pasted by elastic material making also, connect along its length, be provided with one every certain width by certain way, distance between two walls that approximate design of raised line height, guaranteed the relative space position of each wall, do not make it produce contact friction, and the raised line between last lower wall surface produces mechanical snap mutually, prevent each individual layer movable wall sideslip, for the movable wall that contacts with rotating cylinder, surface of contact cover the big material of friction factor outward and on rotating cylinder preset-groove skid preventing, sideslip is except that in addition each layer movable wall covers self lubricating material to reduce running resistance all.Charge into the fluid of lubricated usefulness between each wall, to guarantee pressure balance and to carry out the transmission of power that as the signal of Fig. 5, the superimposed tuple of individual layer movable wall then can be decided as required.
Similar because of the conveyor belt on movable wall system motion form and the conveyor, so improving a little, the many parts on the delivery system device promptly can be used for the movable wall damping device.For example movable wall can be made by the flexible material of the certain tensile strength of tool, in most cases improve a little and can meet the demands with conveyor belt, can select core band type number after the good required tensile strength of calculated in advance for use, cover the big rubber-like surface layer of friction factor outward with the rotating cylinder contacting side, all the other surface layers all cover teflon class self lubricating material, after gluing positioning convex strip, its operation that is installed on the rotating cylinder is also similar with the conveyor belt installation procedure, but installation precision requires high, especially multiple movable wall, there is deviation will cause the space of adjacent wall excessive slightly, positioning convex strip is ineffective, system can not run well, or produces contact friction with contiguous movable wall and influence its slide relative, makes finished product and dispatches from the factory so the movable wall that multiple mantle is formed by stacking is preferably in special producer.If installation precision is difficult to control, the form of guide rail and guide-track groove and so on that also positioning convex strip can be designed to is to retrain the relative tertiary location of each double wall face.
Various rotating cylinders on the also available conveyor of rotating cylinder on the movable wall device improve a little to be made, but bearing will be noted the applicable elements and the support problem of high-speed bearing when selecting.Also can adorn drive motor in case of necessity in the rotating cylinder and become the driving rotating cylinder to drive the movable wall motion.
Select for use about seal arrangement, seal arrangement is mainly arranged along shell edge and main movable wall intersection, if what fill in the device is not allow leakage hydrogen gas and so on hazmat, then obturator is strict, even can consider magnet fluid sealing etc., if allow the fluid of part leakage rate, then adopt general Seal Design also can, interior in many cases outer fluid is identical, and then sealing can be cancelled.
In fill the lubricated fluid of using, generally select the fluid that coefficient of viscosity is little, density is little, if by drag reducing fluid is gas, gases such as then first-selected hydrogen, helium, but if then seal arrangement is strict for the dangerous hydrogen of choosing, if is liquid, then select the fluid that coefficient of viscosity is little, lubrication is arranged, as macromolecule polymer solution etc. by drag reducing fluid.As select for use gas then should note keeping the balance of air pressure and hydraulic pressure, especially vertical surperficial position should add special arrangement or through the special design balance that just can keep-up pressure.Wouldn't discuss at this.
Support and shell and shell and can be as required determined flexibly by the means of fixation of drag reduction body surface sometimes can be cancelled the part shell and replace its function by body surface.
Some now full-fledged conveyor technology such as safe operation monitoring technology etc. also can directly or slightly be used for this device after the improvement.
Difference along with use occasion, the member of this damping device is formed, form and installation compound mode all can be different, but basic comprising and compound mode are roughly constant, promptly by the master, (son) dependent activity wall system, shell, seal arrangement and institute fill lubricating fluid and form, main movable wall system forms member to be had: rotating cylinder and bearing thereof the member of rotating cylinder effect (or play), rotating cylinder support (band tightens up stretching device sometimes), movable wall (individual layer or multiple) etc., movable wall twines and is overlying on the rotating cylinder, can rotate with rotating cylinder and move, rotating cylinder is fixed on the shell with support, also can be directly fixed on by the drag reduction body surface sometimes.Seal arrangement can make to enclose to fill in the space to lubricate and escape with fluid is unlikely, (son) dependent activity wall system is by rotating cylinder and bearing, support, movable wall is formed, its function and structural relation are identical with main movable wall system, one or more main movable wall system can determine compound mode as required flexibly with a plurality of dependent activity wall systems, installation form etc., the movable wall of fluid drives master movable wall system during work, by the internal flow friction, drive each dependent activity wall system and subtense angle successively, the motion of dependent activity wall system and sub-subordinate wall activity system has reduced the running resistance of main movable wall system conversely, main movable wall is speeded up, with constantly reduced by the drag reducing fluid relative velocity until equilibrium state, thereby finish the drag reduction process jointly.
Enforcement the invention has the beneficial effects as follows: broken through the limitation of present various drag reduction methods, device construction is simple, economical, and fitting operation is convenient, and drag-reduction effect is obvious, and application area and application prospect are extremely widely arranged.
Description of drawings:
The invention will be further described for existing accompanying drawings and embodiment
Fig. 1 is a simple movable wall damping device schematic representation
Fig. 2 is a flywheel drag reduction schematic representation
Fig. 3 is a schematic representation of arranging dependent activity wall system in chamber 2
Fig. 4 arranges dependent activity wall system schematic in chamber 1
Fig. 5 is that multiple movable wall positioning convex strip is installed and each stacked mode schematic representation that closes
Fig. 6 is multiple first embodiment's of movable wall damping device a generalized section
Fig. 7 is the generalized section of second enforcement of multiple movable wall damping device
1. rotating cylinders and bearing among the figure, 2. rotating cylinder support, 3. substance or multiple movable wall, 4. obturator, 5. crust of the device, 6. flywheel, 7. the firm matter cylinder of thin-walled, 8. chamber 1, and 9. chamber 2,10. main movable wall system, 11. dependent activity wall system, 12. sub-dependent activity wall systems, 13. positioning convex strips, 14. each individual layer movable wall, 15. by the drag reduction object.
Embodiment:
Embodiment one: shown in Figure 6 is a schematic representation that typically is mainly used in the multiple moveable wall surface drag reduction device for fluid of interior stream drag reduction, wherein main movable wall system chamber 1 position is with a dependent activity wall system, chamber 1 position of this slave system is with a sub-dependent activity wall system again, its support all connects mutually and is fixed on the shell, main movable wall system chamber 2 location arrangements a dependent activity wall system, the chamber 1 of this slave system and chamber 2 positions are respectively equipped with a sub-dependent activity wall system again, each movable wall system is by movable wall, rotating cylinder and support are formed, each space in the whole device is full of the lubricated fluid of using, movable wall is superimposed and layer by multiple individual layer movable wall, and concrete tuple is decided as required.Institute fills fluid and also can decide according to purposes, as be applied to optional water-fillings such as canal for water conveyance or Crude Oil Transportation road or high molecular polymer aqueous solution etc., as be applied to natural-gas transfer pipeline and then can fill hydrogen, helium, air etc., also can cancel seal arrangement and charge into by drag reducing fluid homogeneity homomorphism fluid.Device length is very long during practical application, generally all cancel shell and be directly installed on various channels surface, by saveall is taken up space, often adopt a plurality of rotating cylinder power transmissions that movable wall is turned to, thereby the movable wall upper and lower surface distance of each movable wall system is dwindled, promptly reduce the height of chamber 1 and chamber 2, arrange the position of rotating cylinder except that the end like this and need account for certain installing space, all the other positions take up space very little, have also reduced the consumption of lubricating fluid.
Embodiment two: shown in Figure 7 then is a scheme of installation that typically is mainly used in the multiple moveable wall surface drag reduction device for fluid of outflow drag reduction, compound mode is that two main movable wall systems are arranged side by side, four rotating cylinders of one of them main movable wall system are installed in by on four summits of drag reduction object with support, main movable wall will be surrounded by the drag reduction object, and another main movable wall system is being positioned on a side, the movable wall backhaul side of two main movable wall systems is adjacent as we can see from the figure, because of their moving direction unanimity, speed about equally, so can save all dependent activity wall systems that two main movable wall systems are positioned at chamber 2 positions.The drag reduction of slender type object that the present embodiment mounting type is particularly useful for moving in the fluid such as bullet train, guided missile, submarine, torpedo.Present embodiment two end housings are that the link by the end is fixed in by on the drag reduction object, main movable wall during through the object two ends moving direction vertical with the fluid motion direction, its resistance is bigger, so two ends arrange that all dependent activity wall system gives drag reduction.Movable wall in the present embodiment is multiple superimposed, and concrete tuple can be decided as required.Can increase each the dependent activity wall system's number of chamber 1 part and multiple movable wall tuple during practical application increasing drag-reduction effect, to fill selecting for use with embodiment one of lubricating fluid identical, do not repeat them here.
Claims (3)
1. damping device that reduces the fluid friction resistance, can be installed between the body surface and fluid that needs drag reduction, it is characterized in that: device is that interface is movable (being movable wall) with the surface that is contacted by drag reducing fluid, can do not change fluid with by the situation of drag reduction relative motion of object state under with the fluid motion campaign, thereby reduce relative velocity between interface and the fluid.
2. damping device according to claim 1, it is characterized in that: movable wall can be formed by stacking by multiple movable wall, can be free to slide in a certain direction between each double wall face, various walls surround the space that forms can charge into the lubricated fluid of using, generate certain velocity gradient successively between each double wall face during work, bear certain relative velocity respectively, finish the drag reduction action jointly.
3. damping device according to claim 1, it is characterized in that: the surface friction drag that movable wall when operation internal lubrication fluid produces can arrange that one deck gives drag reduction to multilayer dependent activity wall system, sub-dependent activity wall system, main movable wall system and dependent activity wall system can be as required in many ways flexible combination finish drag reduction jointly and move.
Priority Applications (3)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNA2005100361797A CN1730950A (en) | 2005-07-29 | 2005-07-29 | Multiple moveable wall surface drag reduction device for fluid |
| PCT/CN2006/001825 WO2007012267A1 (en) | 2005-07-29 | 2006-07-24 | Methods for reducing fluid resistance and an apparatus for the same |
| CNB2006101067324A CN100489318C (en) | 2005-07-29 | 2006-07-24 | Multi-layer movable wall fluid resistance-reduction and propulsion device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNA2005100361797A CN1730950A (en) | 2005-07-29 | 2005-07-29 | Multiple moveable wall surface drag reduction device for fluid |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN1730950A true CN1730950A (en) | 2006-02-08 |
Family
ID=35963359
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CNA2005100361797A Pending CN1730950A (en) | 2005-07-29 | 2005-07-29 | Multiple moveable wall surface drag reduction device for fluid |
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| CN (1) | CN1730950A (en) |
| WO (1) | WO2007012267A1 (en) |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102777450A (en) * | 2012-07-26 | 2012-11-14 | 上海交通大学 | Novel resistance-reducing structure of high-speed surface |
| CN103270321A (en) * | 2010-11-22 | 2013-08-28 | 马克思-普朗克科学促进协会 | Eliminating turbulence in wall bounded flows |
| CN109505829A (en) * | 2018-11-28 | 2019-03-22 | 中国核电工程有限公司 | A kind of passive modular fluid resistance element |
| CN110636685A (en) * | 2019-09-10 | 2019-12-31 | 空气动力学国家重点实验室 | Wall drag reduction mechanism based on plasma generator |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101737382A (en) * | 2009-11-13 | 2010-06-16 | 邹立松 | Fluid resistance reducing method and resistance-reduction propulsion unit |
Family Cites Families (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5619945A (en) * | 1996-01-16 | 1997-04-15 | The United States Of America As Represented By The Secretary Of The Navy | Drag reduction polymer ejection system for underwater vehicle |
| CN1492155A (en) * | 2002-01-31 | 2004-04-28 | 金荣国 | Method for reducing motion resistance |
| US7070850B2 (en) * | 2002-12-31 | 2006-07-04 | 3M Innovative Properties Company | Drag reduction article and method of use |
-
2005
- 2005-07-29 CN CNA2005100361797A patent/CN1730950A/en active Pending
-
2006
- 2006-07-24 WO PCT/CN2006/001825 patent/WO2007012267A1/en active Application Filing
Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103270321A (en) * | 2010-11-22 | 2013-08-28 | 马克思-普朗克科学促进协会 | Eliminating turbulence in wall bounded flows |
| CN103270321B (en) * | 2010-11-22 | 2015-06-03 | 马克思-普朗克科学促进协会 | Method for eliminating turbulence in wall bounded flows |
| CN102777450A (en) * | 2012-07-26 | 2012-11-14 | 上海交通大学 | Novel resistance-reducing structure of high-speed surface |
| CN103527575A (en) * | 2012-07-26 | 2014-01-22 | 上海交通大学 | Novel high-speed surface resistance reduction device |
| CN109505829A (en) * | 2018-11-28 | 2019-03-22 | 中国核电工程有限公司 | A kind of passive modular fluid resistance element |
| CN110636685A (en) * | 2019-09-10 | 2019-12-31 | 空气动力学国家重点实验室 | Wall drag reduction mechanism based on plasma generator |
| CN110636685B (en) * | 2019-09-10 | 2021-09-28 | 空气动力学国家重点实验室 | Wall drag reduction mechanism based on plasma generator |
Also Published As
| Publication number | Publication date |
|---|---|
| WO2007012267A1 (en) | 2007-02-01 |
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