CN1846060A - System and method for thermal management using distributed synthetic jet actuators - Google Patents

Abstract

One embodiment of the device comprises a device for thermal management. More particularly, one embodiment comprises a synthetic jet actuator (60) and a tube (61). The synthetic jet actuator (60), though not required, typically comprises a housing (47) defining an internal chamber (45) and having an orifice (46) in a wall (44) of the housing (47). The synthetic jet actuator (60) typically also comprises a flexible diaphragm (42) forming a portion of the housing (47). The tube (61) of this exemplary embodiment typically comprises a proximal end (64) and a distal end (65), the proximal end (64) being positioned adjacent to the synthetic jet actuator (60). In this embodiment, operation of the synthetic jet actuator (60) causes a synthetic jet stream (52) to form at the distal end (65) of the tube (61).

Description

Utilize distributed synthetic jet actuators to carry out the system and method for heat management

Technical field

The present invention relates generally to thermal management technology, relate in particular to and utilize distributed jet actuators to cool off the system and method for heater or element.

Background technique

The cooling heater is the problem of being paid close attention in many different technologies field.Especially in microprocessor, caused demand for the new cooling way that surmounts traditional hot management technology with the rising of the heat radiation grade of contraction heat budget (thermal budget).In addition, for being used in small hand held devices, such as portable digital-assistant (PDA ' s), mobile phone, portable CD Player and similarly the demand of the available heat management strategy in the consumer products increase widely.Really, heat management is to reach the design of intergrated circuit of recent technological advances level and the main challenge of encapsulation technology in single-chip and the multi-chip module at present.

Traditionally, the demand of cooling large-sized microelectronic device is by using the forced convection air-cooled technology to be met.Can both carry out forced convection being with or without under the situation of radiator.And adopt fan that comprehensive cooling or local cooling are provided traditionally.

Fan can provide abundant volume flow rate, but the use of fan has several significant disadvantages.For with given volume flow rate heat extraction, the efficient of fan is lower.In addition, use the comprehensive or local heat of cooling environment of fan usually can cause producing electromagnetic interference and noise based on the fan motor of magnetic.Use fan also to need a large amount of relatively motion parts, so that can cool off hot body or microelectronic element.Thus or because other reasons, fan has limitation aspect long-term reliability.

Movable electrical appliances has been introduced this extra complicated factor of spatial constraints, and this may be difficult to utilize fan to realize Expected Results, and thermal management requirements increase simultaneously causes using the bigger higher flow velocity of fans drive.Because the power dissipation demand causes and must directly place fan on the radiator in some cases, so the caused coherent noise grade of fluidal texture interaction effect has become extra focus.

In some cases, as in handheld devices such as similar portable digital-assistant (" PDAs "), cell phone, the heat of generation is met by the strategy that heat spreader is distributed to the handheld device shell by employing for the demand of heat management.Therefore, the heat that is generated has been scattered and disappeared through natural convection by the shell or the surface of equipment.

Although these methods are very general, they have some defective, and these defectives will be aggravated along with the exploitation of the new product that produces more heats.Adopt the difficulty of hot interspersion strategy to be that just it often can not effectively remove enough heats.In addition, institute's dispersed heat can cause the handheld device case temperature to raise, and this uses the viewpoint of ergonomics from the Consumer is unfavorable.

Making great efforts to improve in the process of some restrictions that have cooling technology now, in heat management, using synthetic after deliberation or " zero clean mass flow rate (zero-net-mass-flux) " jet actuators.For example, U.S. Patent No. 6123145 has been discussed the use synthetic jet actuators and has been cooled off.Therefore, U.S. Patent No. 6123145 is all merged to come in as a reference, just as stating at this fully.Different with conventional jets, synthetic jet actuators does not need to increase quality to system, therefore provides a kind of effective direct airflow to cross the compact way of hot surface.Because jet flow produces from ambient fluid fully, so they can form integral body expediently and not need complicated pipe fitting.

As another example of the thermal management technology exploitation of using synthetic jet actuators, Glezer and Mahalingam have developed the apparatus and method that are used for the path cooling.These apparatus and method have illustrated in U.S. Patent No. 6588497, therefore it are all merged to come in as a reference, just as stating at this fully.

Although the technology described in the aforesaid U.S. Patent has solved some restrictions in the industry, but still exists for improving aforementioned techniques, ever-increasing demand.For example, need more effective, more abundant or compacter synthetic jet actuators.It is desirable to, obtain compacter cooling unit.On the other hand, also need to make cool stream to be distributed to the distant place part of thermal environment.

Therefore, there is demand still unsatisfied up to now, that wish to solve aforementioned deficiency in the industry.

Summary of the invention

Embodiments of the invention provide a kind of device that carries out heat management in various environment.Or rather, present embodiment comprises by using synthetic jet actuators to come the device of cooled region or equipment in distributed cooling unit.

In brief, except other aspects, an embodiment's of this device structure can realize that this device comprises synthetic jet actuators and path by a kind of device that is used for heat management.The path of present embodiment generally includes proximal end and distal end portion, the contiguous synthetic jet actuators of proximal end.The work of synthetic jet actuators preferably makes at the distal end portion formation synthesizing jet of path.Certainly, also can form synthesizing jet at the proximal end place of path.

Although optional, present embodiment or other embodiments' synthetic jet actuators can comprise shell, and this shell defines inner room and has at least one aperture that is formed in the casing wall.The synthetic jet actuators of present embodiment also preferably includes the device that is used to change the inner room volume, wherein preferably adjacent housings setting of volume modifier.In certain embodiments, in fact the device that is used to change volume can form the part of synthetic jet actuators shell.For example, some embodiments' volume modifier comprises the flexible partition of a part that has formed the synthetic jet actuators shell.

In certain embodiments, path is made of one or more pipelines of the outer surface that is connected to the synthetic jet actuators casing wall.In these embodiments, pipeline surrounds at least a portion in synthetic jet actuators aperture usually.

Based on the following drawings and detailed description, for those of ordinary skills, other system of the present invention, method, feature and advantage will become apparent.All these additional system, method, feature and advantage all are included in this specification, do not exceed scope of the present invention, and are protected by subsidiary claim.

Description of drawings

Many aspects that the present invention may be better understood with reference to the following drawings.Constituent element in the accompanying drawing and nonessential drafting according to a certain percentage clearly illustrate principle of the present invention but should focus on.In addition, in the accompanying drawings, identical reference character is represented corresponding part all the time in a plurality of accompanying drawings.

Figure 1A is zero first embodiment's of mass flow rate (zero net mass flux) synthetic jet actuators the cross-sectional schematic side view only with control system.

Figure 1B is the cross-sectional schematic side view of synthetic jet actuators shown in Figure 1A, shows the jet flow that causes barrier film to form when the aperture moves inward when control system.

Fig. 1 C is the cross-sectional schematic side view of synthetic jet actuators shown in Figure 1A, shows when control system causes barrier film and leaves the outside jet flow that forms when mobile in aperture.

Fig. 2 is second embodiment's of synthetic jet actuators a cross-sectional side view.

Fig. 3 is second embodiment's of a synthetic jet actuators shown in Figure 2 bottom view.

Fig. 4 A is the cross-sectional side view of distributed cooling unit.

Fig. 4 B is the cross-sectional, top view of distributed cooling unit that is used for fluid stream is guided into the zones of different of thermal environment.

Fig. 5 A is the pipeline that is used for distributed cooling unit shown in Fig. 4 A at the cross-sectional side view when taking out fluid on every side.

Fig. 5 B is the cross-sectional side view of pipeline when pipe outlet produces synthesizing jet that is used for distributed cooling unit shown in Fig. 4 A.

Fig. 6 is the 3-D view of the distributed cooling unit of multi-actuator type.

Fig. 7 is the cross-sectional side view of the distributed cooling unit of multi-actuator type shown in Figure 6, concentrates on one " between supercharging " of the distributed cooling unit of multi-actuator type.

Fig. 8 is the cross-sectional side view of the distributed cooling unit of multi-actuator type shown in Figure 6, concentrates on one " between supercharging " of device, and wherein actuator is installed in " between supercharging ".

Fig. 9 is the three-dimensional cut-away view of the distributed cooling unit of multi-actuator type shown in Figure 6.

Figure 10 is the incision schematic rear view of the distributed cooling unit of multi-actuator type shown in Figure 6.

Figure 11 A is the side view that is implemented into the distributed cooling unit of multi-actuator type shown in Figure 6 in the cooling system.

Figure 11 B is the front elevation that is implemented into the distributed cooling unit of multi-actuator type shown in Figure 6 in the cooling system.

Figure 12 A is the side view of the cooling system of prior art.

Figure 12 B is the side view of cooling system shown in Figure 12 A, and the distributed cooling unit of multi-actuator type wherein shown in Figure 6 has been installed in this cooling system.

Embodiment

I. synthetic jet actuators

A. the basic design of typical synthetic jet actuators

Figure 1A represents an example of synthetic jet actuators 10, comprises the shell 11 of determining and having surrounded inner room 14.Shell 11 and inner room 14 can be taked any geometrical configuration in fact, but for the ease of discussing and understanding, be illustrated in shell 11 among Figure 1A with cross-sectional form and have hard sidewall 12, hard antetheca 13 and metacneme 18, this metacneme can be deformed to a certain degree to allow diaphragm 18 with respect to inner room 14 inwardly and outwards motion.It can be the aperture 16 of Any shape that antetheca 13 has.The aperture is fully relative with metacneme 18, and makes inner room 14 be connected to the external environment condition with ambient fluid 39.

Can control flexible partition 18 motions by any suitable control system 24.For example, barrier film 18 can be provided with metal layer, but the metal film adjacent metal layers but be arranged with the metal layer branch so that barrier film 18 can be driven to produce and moves by being applied to electrical bias between electrode and the metal layer.In addition, can be by the generation of any proper device control electrical bias, such as but not limited to computer, logic processor or signal generator.Control system 24 can make barrier film 18 periodically move or be adjusted to the time harmonic motion, and force fluid to flow into and outflow aperture 16.

Work referring now to the synthetic jet actuators 10 of Figure 1B and 1C illustrated example.Figure 1B represents when the controlled synthetic jet actuators 10 during as shown in arrow 26ly to chamber 14 internal motions of barrier film 18.The volume of chamber 14 reduces and fluid ejects by aperture 16.When fluid passed through aperture 16 delivery chamber 14, fluid stream separated at sharp keen orifice edge 30 places and forms backset bed 32, and this backset bed is rolled into whirlpool 34 and begins and move apart orifice edge 30 on by arrow 36 indicated directions.

Fig. 1 C represent when barrier film 18 controlled as shown in arrow 38ly with respect to the outside synthetic jet actuators 10 during motion in chamber 14.The volume of chamber 14 increases and ambient fluid 39 pours in the chamber 14, shown in arrow group 40.Barrier film 18 is by control system 24 controls, thereby when barrier film 18 left chamber 14, whirlpool 34 had left orifice edge 30, thereby can not be subjected to introducing the influence of the ambient fluid 39 in the chamber 14.Meanwhile, whirlpool 34 entrainments consumingly from being away from the ambient fluid that aperture 16 parts attract, thereby has synthesized the jet flow of ambient fluid 39.

B. has the synthetic jet actuators that mixes piezoelectric actuator

As mentioned above, the barrier film 18 of first embodiment's synthetic jet actuators 10 comprises electric actuator, and described electric actuator is made up of metal film and metal layer with the particular excitation frequency drives.This electric excitation makes the barrier film 18 of synthetic jet actuators 10 vibrate, thereby changes the internal capacity of the chamber 14 of synthetic jet actuators 10.

Alternatively, as shown in Figure 2, synthetic jet actuators 40 can comprise the shell 47 of having determined chamber 45.The volume of this chamber can be changed by flexible partition 42 is moved with the time harmonic motion mode, and this motion is caused by piezoelectric actuator 41 excitation barrier films 42.Fig. 2 is the cut-away side view with synthetic jet actuators 40 of shell 47, and this shell is determined by firmer domed wall 43, firmer cylinder side wall 44 and the flexible partition 42 that formed the diapire of actuator 40.As shown in the figure, sidewall makes roof 43 be connected to barrier film 42.Preferably, sidewall 44 and roof 43 are made by the single-piece hard material, such as plastics etc.Certainly, also can have suitable hard material and construct wall 43,44 by metallic material or other.In addition, the material of formation synthetic jet actuators 40 needs not to be rigidity.Material can have some flexibilities.Those of ordinary skills will be easy to find out the appropriate material that is suitable for synthetic jet actuators 40 based on specific mode of execution.

As mentioned above, roof 43, flexible partition 42 and sidewall 44 have formed the shell 47 of synthetic jet actuators 40 and have determined to have the chamber 45 of volume.The shell 47 of present embodiment 40 has cylindrical shape.This kind configuration is optional, and selected specified configuration is in order to make the people understand this point: promptly synthetic jet actuators 40 can be taked almost any global shape.

In the present embodiment of synthetic jet actuators 40, aperture 46 is formed in the part of sidewall 44.But aperture 46 jet ground junction chamber 45 and ambient fluids 48.The concrete size and the shape in aperture 46 are unimportant for present embodiment 40.As an example, aperture 46 can be level or the vertical groove in circular open or the sidewall 44.

Fig. 3 is second embodiment's of synthetic jet actuators 40 a planimetric map, has more properly represented piezoelectric actuator 41 and flexible partition 42.In other words, Fig. 3 can be imagined as from " bottom " of downside or actuator 40 and see synthetic jet actuators 40.As can be seen from Figure, barrier film 42 is connected on the sidewall 44.Preferably, barrier film 42 is connected on the sidewall 44 by the tackiness agent that is suitable for being used for constructing the material of barrier film 42 and sidewall 44.Alternatively, barrier film 42 can be connected on the sidewall 44 by other bindiny mechanisms or equipment.Connecting means is inessential for present embodiment 40.But, preferably selected connecting means can make sealing between sidewall 44 and the barrier film 42.

Barrier film 42 preferably is made of elastomer or polymer material.Elastomer or membrane for polymer 42 are optional in the present embodiment; But, the barrier film that is made of these materials is preferred.Traditionally, piezoelectric actuator is made of the metal diaphragm that is connected with piezo-electric sheet.But, in some embodiments advantageously, utilize polymerization (similar plastics) or elasticity (rubber like) material to constitute the barrier film of piezoelectric actuator.Alternatively, polymerization or elastic diaphragm can combine use with metal diaphragm and mix barrier film to form.

Elastomer or polymer can be made of many certain materials, such as polyisoprene, polyisobutylene, polybutadiene and/or polyurethane.For present embodiment 40, because elastomer or polymer material have the ability that still can bounce back into its original shape after being stretched and permanent deformation does not take place, so select it to construct barrier film 42.

The actuator structure of this modification has two advantages at least.The first, use elastomer or membrane for polymer generally can reduce the natural resonant frequency of actuator, make it more preferably (for example,＜200Hz) use with low frequency.This makes that the operational sound of actuator is smaller.The second, and trend towards at piezoelectric material and be commonly used to piezoelectric material is attached to the metal diaphragm that produces bigger stress in the tackiness agent on the metal comparing, this structure generally has good reliability.

As mentioned above, piezoelectric actuator 41 is connected on elastomer or the membrane for polymer 42.Piezoelectric actuator 41 preferably is installed on the barrier film 42 by suitable bonding.Piezoelectric actuator 41 provides electric energy by electric lead 49.Electric lead 49 not only provides electric energy to piezoelectric actuator 41, also controls the work of actuator 41.Exactly, lead 49 couples together piezoelectric actuator and power supply and control system 50, and this control system is preferably separated with the shell 47 of synthetic jet actuators 40.Certainly, in certain embodiments, power supply and control system 50 can be installed on the shell 47 of synthetic jet actuators 40, perhaps even can be installed in the shell 47.

Power supply and control system make piezoelectric actuator 41 vibrations.The vibration of piezoelectric actuator 41 makes barrier film 42 vibrate with the form of time harmonic motion.Piezoelectric actuator 41 preferably vibrates with the resonant frequency of barrier film 42.Certainly, can control the Oscillation Amplitude and the frequency of barrier film with different frequency work by making piezoelectric actuator.Those of ordinary skills will be easy to adjust the vibration of piezoelectric actuator 41, so that produce the vibration frequency and the amplitude of desirable barrier film 42.

As above relevant first embodiment 10 is described, and the vibration of the barrier film 42 among second embodiment 40 causes forming at 46 places, aperture of actuator 40 synthesizing jet 52 of fluid.When barrier film 42 with respect to chamber 45 inwardly during motion, the volume of chamber 45 reduces and fluid penetrates by aperture 46.When fluid penetrated in chamber 45 by aperture 46, at orifice edge punishment stream and formation backset bed, backset bed was rolled into whirlpool and leaves aperture 46.These vortices entrain ambient fluids 48 also utilize this fluid to form synthesizing jet 52.

Be similar to the work of the synthetic jet actuators 10 of first example, when barrier film 42 outwards moved with respect to chamber 45, the volume of chamber 45 increased.The increase of volume causes the 46 places formation pressure gradient in the aperture, thereby ambient fluid 48 pours in the chamber 45.Then, in the time of in barrier film 42 shakes go back to chamber 45, the fluid in the chamber 45 is discharged from, and forms aforesaid synthesizing jet 52.

III. distributed cooling unit

A. first example: single actuator devices

Aforesaid synthetic jet actuators 10,40 can be used among many different embodiments.But, a special modification of synthetic jet actuators 10,40 is preferred for the distributed cooling application of being known as.It is to require single synthetic jet actuators that the situation of cooling synthesizing jet is provided to a plurality of positions that distributed cooling is used.Alternatively, distributed cooling use can require synthetic jet actuators to from the actuator position slightly some single position far away chilled fluid flow is provided.Although be not restrictive example, these two examples are that common distributed cooling is used.

Fig. 4 A represents an embodiment of distributed cooling synthetic jet actuators 60.For convenience of explanation, the embodiment of distributed cooling synthetic jet actuators 60 has been designed to second embodiment's 40 improved form.Like this, distributed cooling synthetic jet actuators 60 comprises the shell 47 of having determined inner room 45.Any geometrical configuration can be adopted in shell 47 and chamber 45, but for the ease of discussing and understanding, be illustrated in shell 47 among Fig. 4 A with cross-sectional form and have hard sidewall 44, hard roof 43 and barrier film 42, this barrier film can be deformed to a certain degree to allow barrier film 42 with respect to chamber 45 inwardly and outwards motion.The part of sidewall 44 has formed aperture 46.As mentioned above, aperture 46 can have any geometrical shape.

As above embodiment 40, distributed cooling synthetic jet actuators 60 also comprises power supply and the control system 50 that is connected to the piezoelectric actuator 47 on the barrier film 42 by electric lead 39.As mentioned above, power supply and control system 50 can be away from actuators 60, perhaps for example can be connected on the shell 47 or place in the shell 47.

Exemplary distributed cooling unit 60 also comprises path or pipeline 61.The shape of cross section of pipeline 61 can be similar to the shape of cross section in aperture 46.But, the shape of cross section of pipeline 61 also can be different from the shape in aperture 46 fully.For example, use the varying cross-section shape can more effectively guide any fluid that penetrates from pipeline 61.Pipeline 61 is preferably formed by the duricrust 62 that surrounds inner region 63.Pipeline 61 also comprises proximal end or connecting end 64 and distal end portion or opening end 65.Can be harder but still very light thereby pipeline 61 preferably constitutes pipeline 61 by plastics.Alternatively, pipeline 61 can be by forming a kind of shape and keeping the flexible material of this shape to constitute.In Fig. 4 A, pipeline 61 forms and is snakelike substantially.The shape of pipeline 61 is unimportant for principle of the present invention, and represented given shape is only selected for the principle of graphical illustration present embodiment 60.

As shown in the figure, pipeline 61 preferably is connected on the sidewall 44 of synthetic jet actuators 60, thereby but the mode that the actuator aperture is communicated with fluid is connected to the inner region 63 of pipeline 61.In preferred structure, the internal diameter of pipeline 61 is equal to or greater than the diameter in aperture 46.Like this, aperture 46 can directly not communicate with peripheral environment 48, and perhaps in other words, pipeline 61 covers aperture 46 fully.Although pipeline 61 preferably ' attach ' on the sidewall 44, should understand, shell 47 and pipeline 61 can be made by from one piece.

As following elaboration in more detail, in operating process, eddy current is formed on the edge of pipe outlet 65.These eddy current roll and leave the outlet 65 of pipeline 61.These eddy current are inhaled the volume ambient fluid and are formed jet 52 at outlet 65 places of pipeline 61.In fact, use pipeline 61 that jet 52 is shot out from pipeline 61, leave actuator itself.Basically, if there is no pipeline 61, so originally will be from the synthetic jet actuators aperture synthetic jet of 46 fluids that penetrate will change into from the outlet end 65 of pipeline 61 and penetrate.This feature of present embodiment 60 makes Cooling System Design person to be positioned at any position easily to synthetic jet actuators 40, and still can be by simply pipeline 61 being pointed to the position of wanting and fluid stream 52 is guided to distant position.

For example, actuator 40 can be positioned on the position that has with a certain distance from the zone that will be cooled, such as in position placed in the middle.Pipeline 61 can be shaped as the heat-dissipating fin directing fluid stream by radiator.Near the synthetic jet actuators not fact radiator generally can make the fluid stream of the heat-dissipating fin by radiator increase.In fact, if actuator position in the ingress of heat-dissipating fin path, the existence that fails to be convened for lack of a quorum owing to actuator housings through the fluid of heat-dissipating fin path is prevented from so.This does not just become problem to utilize distributed cooling.

As mentioned above, pipeline 61 can be preformed or flexible.If flexible, the artificer can make pipeline 61 be configured as desired shapes by apparatus for placing 40 then so.This is very helpful for retrofit application.But, in most of common embodiments, pipeline 61 can be harder, thereby can adjust whole Cooling System Design subtly before installing.

As mentioned above, the shape of pipeline 61 or size are unimportant for present embodiment 60.But, the length of pipeline 61 and/or shape can influence the performance of distributed cooling synthetic jet actuators 60.For this point is described better, should be by means of the operation of distributed cooling unit 60.

The class of operation of the synthetic jet actuators 40 in the distributed cooling unit 60 is similar to the operation of synthetic jet actuators among above-mentioned second embodiment.Specifically, piezoelectric actuator 41 preferably vibrates with the resonant frequency of barrier film 42 with suitable frequency.This vibration causes barrier film 42 to vibrate in the mode of time harmonic motion.When barrier film 42 inwardly moved with respect to inner room 45, the volume of chamber 45 reduced, and the pressure in the chamber 45 increases, and 46 places form pressure gradient in the aperture, and fluid penetrates from the aperture 46 of synthetic jet actuators 40.Because 46 places do not have ambient fluid to introduce in the aperture, the fluid that therefore in fact flows out aperture 46 is pulsed usually, generally reflects the frequency of the barrier film 42 that is driven by piezoelectric actuator 41.This fluid pulse enters in the inner region 63 of the pipeline 61 that is connected aperture 46.When barrier film 42 outwards moved with respect to chamber 45, fluid was introduced the synthetic jet actuators chambers 45 from pipe interior 63.Then, when barrier film 42 continued its time harmonic vibration and gets back in the chamber 45, fluid was injected the pipe interior 63 from chamber 45 once more.

Fig. 5 A and 5B represent the fluid interaction in inside 63 scopes of pipeline 61 in the operating process of synthetic jet actuators 40 of distributed cooling unit 60.When fluid when synthetic jet actuators chamber 45 enters the inside 63 of pipeline 61, the fluid that enters serves as " virtual piston " 66.Enter the fluid in the pulse compression pipe interior 63 of fluid 66 of pipeline 61 inside 63, thereby cause fluid 67 to be discharged from the outlet end 65 of pipeline 61.When barrier film 42 from the synthetic jet actuators chamber 45 outwards during motion, " virtual piston " 66 outwards moves from the inside 63 of pipeline 61, from pipe interior 63 in the fluid suction chamber 45, thereby reduced pressure in the pipeline 61.This low pressure in the pipeline 61 has formed pressure gradient at pipe outlet 65 places, thereby from every side 48 fluid intake line 61.The fluid at pipeline connecting end 64 places serves as " virtual piston " 66 again, operates in the mode of time harmonic vibration.

The intermediate portion 68 of pipeline 61 serves as another synthetic jet actuators " chamber " 69 that the wall 62 by pipeline 61 limits.The fluid at 46 places, aperture of synthetic jet actuators 40 limits and is somebody's turn to do " chamber " 69, and serves as the virtual piston 66 corresponding to this virtual synthetic jet actuators " chamber " 69.Leave and enter fluid aperture 46, that serve as piston 66 and formed the fluid stream 67 that penetrates from the outlet end 65 of pipeline 61.The fluid 67 that penetrates pipeline 61 has formed eddy current at outlet 65 places of pipeline 61.These eddy current roll and leave pipe outlet 65.When eddy current formed and leaves, these eddy current were entrainmenting ambient fluid 48 so that form synthesizing jet 67 at outlet 65 places of pipeline 61.

According to the length of pipeline 61, can adjust the operation of the barrier film 42 of synthetic jet actuators 40 definitely, in pipeline 61, to form virtual synthetic jet actuators.From above discussion obviously as can be known, and those of ordinary skills can recognize, preferably, should adjust the operation of barrier film 42, penetrate so that the frequency of the air pulse 66 that penetrates from the aperture 46 of synthetic jet actuators 40 is resonant frequencies with pipeline 61.In fact, pipeline 61 plays the effect of Hull Mu Huozi (Helmholtz) type resonator and can work in a similar manner.The closed end of the Helmholtz resonator that the connecting end 64 of pipeline 61 serves as a model, but also provide exciting force to resonator.

If the size of pipeline 61 is known, those of ordinary skills can calculate the resonant frequency of pipeline 61 so.Then, can calculate the frequency and the amplitude of barrier film 42 vibrations, so that the pulse of penetrating from synthetic jet actuators 40 apertures 46 66 is with resonant frequency excitation pipeline 61.Certainly, this can both be controlled automatically by suitable control system 50.

In another exemplary configurations 70 of distributed cooling synthetic jet actuators, synthetic jet actuators 40 is configured to drive many pipelines.This structure is shown in Fig. 4 B.Fig. 4 B is the cut-away top view of distributed cooling synthetic jet actuators.As shown in the figure, the synthetic jet actuators shell 47 of actuator 70 preferably has a plurality of aperture 46a, 46b, 46c, 46d, 46e, 46f.At the many pipeline 61a of being externally connected to of shell 47,61b, 61c, 61d, 61e, 61f, thereby these pipelines 61a, 61b, 61c, 61d, 61e, 61f is corresponding to each aperture 46a, 46b, 46c, 46d, 46e, 46f.Pipeline 61a, 61b, 61c, 61d, 61e, 61f can be configured to fluid stream is guided into identical zone, perhaps in a preferred application, form pipeline like this with synthesizing jet 52a, 52b, 52c, 52d, 52e, 52f guides the thermal region or the target 71a of separation, 71b, 71c, 71d, 71e into.

In another embodiment of distributed cooling unit, it is desirable to, with existing method the synthetic jet actuators module is connected on another surface.For example, if distributed cooling unit will use in the application of remodeling, may not existing connecting means so.In this case, it is desirable to, the roof 43 of synthetic jet actuators 40 is configured to adhere on the surface easily.Synthetic jet actuators 40 can be by " subsides " to the surface.This can realize by using the foamed plastics that all there is tackiness agent on two-sided tape, two sides or the like.

B. second example: multi-actuator device

In some mode of executions of distributed cooling unit, it is desirable to produce a plurality of synthesizing jets.As mentioned above, single synthetic jet actuators 40 can drive a plurality of pipelines, thereby produces a plurality of distributed synthetic jet streams of fluid.Certainly, this is not that the only of the distributed cooling unit of many synthetic jets may mode of execution.Another embodiment can comprise a plurality of synthetic jet actuators that drive a plurality of pipelines, thereby launches a plurality of synthesizing jets.This embodiment's pipeline can point to different zones, different radiator path or all point to identical position.

The embodiment of the distributed cooling unit 80 of multi-actuator type as shown in Figure 6.This device 80 generally comprises a plurality of pipelines 81, is formed by rectangular basically cube shell 82.Shell 82 has two " between superchargings " 83 that are formed in the shell 82, thereby 83 end faces 84 from shell 82 descend between these two superchargings.83 separate with the sidewall 85,86 of shell 82 between these two superchargings, and preferably do not arrive the bottom surface 87 of shell 82 from start to finish.

The cross-sectional side view of the distributed cooling unit 80 of multi-actuator type as shown in Figure 7.Shown between a supercharging of shell 82 83 bottom surface 87, antetheca 88 and rear walls 89 by device 82 limit.Each of antetheca 88 and rear wall 89 all forms a pair of upper mounting plate 91,92 and a pair of lower bolster 93,94.These platforms 91,92,93,94 are preferably by making with wall 88,89 identical materials, and are not only to adhere on the wall 88,89.Certainly, this is not the essential feature of the distributed cooling unit 80 of multi-actuator type.In addition, roof 95 (as shown in Figure 8) can be installed on the device 80 with between the sealing supercharging 83.

Fig. 8 represents to have two actuators 96,97 to place between supercharging within 83 and roof 95 is installed in the later device shown in Figure 7 in 83 tops between supercharging.As shown in the figure, first actuator 96 is supported on the upper mounting plate 91,92 and second actuator 97 is supported on the lower bolster 93,94.These two actuators 96,97 preferably include flexible partition 98,99, and piezoelectric actuator 101,102 is installed on the flexible partition 98,99.Preferred actuator 96,97th, above about embodiment's 40 described elastomer or polymer actuators.Referring to Fig. 2.Also can use other actuators for device described here 80.But, elastomer/polymer actuator is owing to its simple configuration design, the actuating of brute force and cheap cost become preferably.

Provide electric energy and control by the electric lead (not shown) to actuator 96,97.These leads pass through four small channel 103a of the top and bottom sidewall 85,86 of incision shell 82 usually, 103b, and 103c (only illustrating three in Fig. 6) enters in the shell 82.In fact, can predict The whole control circuit (not shown) and can be arranged on these raceway grooves 103a, 103b is among the 103c.Then, preferably only have supply of electrical energy to arrive these raceway grooves 103a, 103b is in the control hardware that 103c and they comprise.

Actuator 96,97 preferably is fastened on the platform 91,92,93,94 in the crust of the device 82.This is preferably by using one type tackiness agent to realize.Because the material of barrier film 98,99 is elastomer or polymer preferably, and the preferred material of shell 82 is plastics, so those of ordinary skills can be easy to select suitable adhesive or other bindiny mechanisms.

In case actuator 96,97 is fastened on the inside of crust of the device 82, then installs between supercharging 83 and be divided into three parts in fact.Actuator 96,97 the chamber that has formed three separation is set, separate but relevant synthetic jet actuators thereby form three.First or bottom compartment 105 limit by outer shell bottom wall 87, shell antetheca 88, housing back wall 89 and second actuator 97.Second Room 106 is limited by first actuator 96, antetheca 88, rear wall 89 and second actuator 97.The 3rd or the top chamber 107 limit by first actuator 96, antetheca 88, rear wall 89 and roof 95.

The embodiment who recalls above distributed cooling unit 60 has the single aperture 46 (Fig. 4 A) of the single pipeline 61 of 45 sensings from the chamber.But, in present embodiment 80, there are one or more apertures 108 each chamber 105,106,107.In embodiment 80, there are two apertures in the antetheca that is formed into crust of the device 82 88 each chamber 105,106,107.But the mode that each aperture also is communicated with fluid is connected to the pipeline 81 that the antetheca 88 by shell 82 forms.Certainly, needn't two apertures 108 and pipeline 81 all be arranged each chamber 105,106,107.If have greater or less than two apertures 108 and pipeline 81, if the aperture and the pipeline of varying number are perhaps arranged for each chamber 105,106,107, present embodiment 80 also can be worked.

Pipeline 81 preferably is being connected to shell 82 in the same horizontal plane basically, as shown in Figure 6.For this reason, Fig. 7 and Fig. 8 seem and have only represented a pipeline 81 (with an aperture 108), and this pipeline is connected to shell 82 in the midpoint near shell antetheca 88.Pipeline 81 comprises connecting end 109, is connected to shell antetheca 88, and comprises fluid outlet 110, but described fluid outlet makes pipe interior 111 be communicated to ambient fluid 112 in the mode that fluid is communicated with.

Because pipeline 81 preferably all is connected on the shell 82 in same horizontal plane, and chamber 105,106,107 in same horizontal plane, therefore, preferably use formed channel 113 with each chamber 105,106, but 107 modes that are communicated with fluid are connected to the aperture 108 and the pipeline 81 of being served by specific synthetic jet actuators.

These passages 113 with port are illustrated in the incision sectional drawing of Fig. 9.In addition, Figure 10 represents the exploded chart of the aperture 108a-f that these three chambers 105,106,107 and each chamber 105,106,107 are served.As an example, among Figure 10, there are two aperture 108e, 108f in first Room 105; There are two aperture 108c, 108d in second Room 106; And there are two aperture 108a the 3rd Room 107,108b.As from Fig. 9 and Figure 10 as seen, the cross section of three chambers 105,106,107 in the shell 82 needs not to be rectangle, thereby also can be that peculiar shape is guided to fluid in the different pipelines 81 of being served by each chamber 105,106,107.

Certainly, in optional embodiment, pipeline 81 needn't be connected on the shell 82 in identical horizontal plane.For example, provide the pipeline 81 of service can be directly connected to chamber 105,106,107 by each chamber 105,106,107.Then, chamber 105,106,107 can construct like this, make them that rectangular substantially cross section be arranged.

Now with the work of the distributed cooling unit 80 of multi-actuator type of illustrated example, concrete simultaneously " between a supercharging " 83 is discussed.The work that will be appreciated that other " between superchargings " 83 is similar.During work, cause two barrier films 96,97 to vibrate by time harmonic motion mode by the control system (not shown), wherein this control system is controlled each piezoelectric actuator 101,102 on each barrier film 98,99.Barrier film 98,99 preferably activates like this and makes two barrier films 98,99 out of phase vibrate each other.

Because two actuators 96,97 moves toward each other, so the volume of second Room 106 reduces and the volume of chamber 107, top and bottom compartment 105 increase.Therefore, second Room, 106 propelling fluids enter pipeline 81 inside 111 that are connected to this chamber 106 from chamber 106.Recall the discussion relevant with above single actuator embodiment 60, this pushing course that makes fluid enter pipe interior 111 plays the effect of " virtual piston " that be similar to fluid.Be used to set forth relevant Fig. 5 A of this process and the description of 5B referring to above.This virtual piston enters pipeline 81 inside 111, the fluid of compression pipe inside 111, thus make the synthesizing jet 115 that forms fluid at pipeline 81 outlet end 110 places that are connected to this second Room 106.

Reaction is born by chamber 107, top and bottom compartment 105.Specifically, owing to two barrier films 98,99 move toward each other, so chamber, top and bottom compartment 107,105 introduce fluid from the pipeline 81 inner 111 that is connected to these chambers 107,105.This makes fluid " virtual piston " enter chamber, top and bottom compartment 107,105, thereby makes the outlet end 110 of the pipeline 81 that is connected to these chambers 107,105 introduce fluid from peripheral 112.

When barrier film 98,99 vibrated away from each other, the volume of second Room increased, and fluid is introduced into the pipeline 81 that is connected to this chamber 106 from peripheral 112.Certainly, the volume of chamber, top and bottom compartment 107,105 also reduces similarly.This makes at the synthesizing jet 115 of the pipeline 81 outlet end 110 places formation fluid that is connected to these two chambers 107,105.

As those of ordinary skills can understand, the working principle of the distributed cooling unit 80 of multi-actuator type and above-mentioned basic distributed cooling unit 60 were closely similar.For example, this embodiment's 80 pipeline 81 serves as the Helmholtz resonator in above-mentioned mode about single actuator distributed cooling unit 60.

A common mode of execution of the distributed cooling unit 80 of multi-actuator type is shown in Figure 11 A and 11B.Certainly, according to the thermal management requirements of system and the structure of device 80, many other mode of executions also are possible for device 80.This mode of execution 120 is the practical range of restricting means 80 not.The illustrative embodiments that proposes only is in order to describe the feature of present embodiment 80 better.

Illustrative embodiments 120 relates to the radiator 121 that uses extruding, so that from the target 122 of heat heat is passed away.The distributed cooling unit 80 of multi-actuator type is provided with like this: make each pipeline 81 in the device 80 be arranged in rows with a series of paths 123 that a series of heat-dissipating fins 124 by radiator 121 form, the path 123 between the heat-dissipating fin 124 thereby jet flow 125 is flowed through.This jet flow 125 is being carried second cooling blast 126 again secretly, and this air-flow is forced into the path 123 of radiator 121.

In another purposes of this refrigerating module 80, utilize the synthetic jet array of pipeline 81 to reduce by the tributary 130 in the radiator 121 of fans drive stream 127 coolings.Figure 12 A represents not have the situation of synthetic jet actuators 80.In this embodiment, fan 128 attracts fluid stream 127 by the path between the heat-dissipating fin 124 of radiating fin 121 123.But, because the pressure drop that the path 123 of radiating fin 121 is produced, most of air-flow 130 is walked around radiating fin 121.This is in many application, such as blade server (blade server), telecommunication s rack (telecom racks) etc., the problem that often runs into, wherein the interval between the element board is very narrow, and exists big fan group to attempt driving mass air flow by being installed in the radiating fin on the thermoelement.

In this embodiment, shown in Figure 12 B, synthetic jet actuators is provided with like this: make the pipeline 81 of actuator 80 that their fluid stream 115 is emptied in the path 123 of radiating fin 121.Should be noted that because the distributed nature of device 80, actuator can be arranged on the below, plane of radiating fin 121, thereby prevents by the fluid flow disturbance.When actuator 80 was started working, tangential synthetic jet 115 was drawn towards near the left hand edge of radiating fin 121.Fan 128 continuous firings.The synthetic jet of the high momentum of low pressure causes producing effective entrained flow 131 of air-flow 130, and this air-flow 130 is before from radiating fin 121 next door processes.

What should emphasize is, the above embodiment of the present invention, especially any " preferably " embodiment only are the examples of possible mode of execution, state just to being expressly understood principle of the present invention.Can carry out many changes and modification to the above embodiment of the present invention and can substantially not break away from spirit of the present invention and principle.All such modifications and change will be included in this specification and the present invention and the scope protected by following claim in.

Claims (40)

1. device that is used for heat management comprises:

Shell, this shell have been determined inner room and have been had aperture in the wall of described shell;

The volume modifier, the contiguous described shell of this device, described volume modifier is used to change the volume of described inner room; And

Pipeline, this pipeline is connected to the outer surface of the described wall of described shell, and described pipeline surrounds at least a portion in described aperture.

2. the described device of claim 1, the control system that also comprises the operation that is used to control described volume modifier, the described operation of wherein said volume modifier is introduced gas described indoor from described pipe interior, and forces gas to leave described chamber and enter described pipe interior.

3. the described device of claim 1, wherein said volume modifier comprises the flexible partition of a part that has formed described shell.

4. the described device of claim 3, wherein said volume modifier also comprises the piezoelectric actuator that adheres to described flexible partition.

5. the described device of claim 4, wherein said flexible partition comprises elastomeric material.

6. the described device of claim 4, wherein said flexible partition comprises polymer material.

7. the described device of claim 1, wherein said pipeline comprises connecting end and opening end, described connecting end is connected to described shell, and the described open end that operates in described pipeline of described volume modifier produces synthesizing jet.

8. the described device of claim 7, wherein said pipeline produces described synthesizing jet in the position away from described shell.

9. the described device of claim 7, the size of wherein said pipeline is set like this: make because the operation of described volume modifier and produce Helmholtz type resonance at described pipe interior.

10. the described device of claim 7 also comprises the radiating fin with heat-dissipating fin, the contiguous described radiating fin setting of the described opening end of wherein said pipeline, thus described synthesizing jet is through between the adjacent heat-dissipating fin.

11. the described device of claim 10 also comprises fan, described fan is arranged on an end of described radiating fin, thereby described synthesizing jet helps described fan to reduce because the tributary that the pressure drop of heat-dissipating fin causes.

12. the described device of claim 1, wherein said inner room comprises:

First seed cell;

Second seed cell of contiguous described first seed cell; With

The 3rd seed cell of contiguous described second seed cell.

13. the described device of claim 12, wherein said first seed cell and described second seed cell are formed by first common wall, and described first common wall is included in the described interior indoor of described shell, and described first common wall comprises first flexible partition.

14. the described device of claim 13, wherein said second seed cell and described the 3rd seed cell are formed by second common wall, and described second common wall is included in the described inner room of described shell, and described second common wall comprises second flexible partition.

15. the described device of claim 14, wherein said aperture also comprise at least one opening in each described seed cell.

16. the described device of claim 15, wherein said pipeline comprise the pipe of contiguous each described at least one opening, at least a portion that described each pipe surrounds described each opening.

17. the described device of claim 16 also comprises:

Be connected to first piezoelectric element of described first flexible partition; With

Be connected to second piezoelectric element of described second flexible partition.

18. the described device of claim 17, wherein said first and second flexible partitions comprise elastomeric material.

19. the described device of claim 17, wherein said first and second flexible partitions comprise polymer material.

20. a device that is used to cool off comprises:

Synthetic jet actuators; With

Path, this path has proximal end and distal end portion, the contiguous described synthetic jet actuators of described proximal end, wherein said synthetic jet actuators causes the formation synthesizing jet.

21. the described device of claim 20, wherein said synthesizing jet are formed on the described distal end portion place of described path.

22. the described device of claim 20, wherein said synthesizing jet are formed on the described proximal end place of described path.

23. the described device of claim 20 also comprises the control system that is used to control described synthetic jet actuators operation.

24. the described device of claim 20, wherein said synthetic jet actuators comprises:

Shell, this shell have been determined inner room and have been had aperture in the wall of described shell;

The volume modifier, the contiguous described shell of this device.

25. the described device of claim 24, wherein said volume modifier comprises the flexible partition of a part that has formed described shell.

26. the described device of claim 25, wherein said volume modifier also comprises the piezoelectric actuator that adheres to described flexible partition.

27. the described device of claim 26, wherein said flexible partition comprises elastomeric material.

28. the described device of claim 26, wherein said flexible partition comprises polymer material.

29. the described device of claim 26, the size of wherein said path is set like this: make owing to the operation of described volume modifier at the inner Helmholtz of generation of described path type resonance.

30. the described device of claim 29, wherein said path comprises pipeline.

31. the described device of claim 29 also comprises the radiating fin with heat-dissipating fin, the contiguous described radiating fin setting of the described distal end portion of wherein said path, thus described synthesizing jet is through between the adjacent heat-dissipating fin.

32. the described device of claim 31 also comprises fan, described fan is arranged on an end of described radiating fin, thereby described synthesizing jet helps described fan to reduce because the tributary that the pressure drop of described heat-dissipating fin forms.

33. the described device of claim 20, wherein said path comprises a part of radiating fin.

34. the described device of claim 20, wherein said synthetic jet actuators comprises first synthetic jet actuators, and described device also comprises:

Second synthetic jet actuators of contiguous described first synthetic jet actuators; With

The 3rd synthetic jet actuators of contiguous described second synthetic jet actuators.

35. the described device of claim 34, wherein said synthetic jet actuators is formed by public shell, and described first synthetic jet actuators and described second synthetic jet actuators are formed by first common wall, and described second synthetic jet actuators and described the 3rd synthetic jet actuators are formed by second common wall.

36. the described device of claim 35, wherein said path comprises first pipeline, and described device also comprises:

Second pipeline with proximal end and distal end portion, contiguous described second synthetic jet actuators of described proximal end; With

The 3rd pipeline with proximal end and distal end portion, contiguous described the 3rd synthetic jet actuators of described proximal end.

37. the described device of claim 36, wherein said first common wall comprises first flexible partition, and described second common wall comprises second flexible partition.

38. the described device of claim 37 also comprises:

Be connected to first piezoelectric element of described first flexible partition; With

Be connected to second piezoelectric element of described second flexible partition.

39. the described device of claim 38, wherein said first and second flexible partitions comprise elastomeric material.

40. the described device of claim 38, wherein said first and second flexible partitions comprise polymer material.

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