CN1766464A - A kind of electricity driven traveling wave thermoacoustic refrigerator system - Google Patents

Abstract

This electricity driven traveling wave thermoacoustic refrigerator system comprises successively the cool end heat exchanger that links to each other and become the loop, regenerator, heater, thermal buffer tube, hot end heat exchanger, annular connecting pipe and be positioned at ducted pressure wave generator; Generator has a cylinder, and sleeve pipe one end in it is enclosed within on the pipeline, and the other end is equipped with the linear slide bearing; Fix a Crossed Circle magnetic conductive soft iron that has an annular cavity in the cavity between cylinder and the sleeve pipe, be embedded with permanent magnet in its outer shroud magnetic wall; The coil brace of coiling is fixed on the cylinder inner wall on the bucket wall, and coiler part inserts in the annular cavity; Scavenging elasticity/quality component is housed in the pipeline of hot junction, and its mass elements is contained in the pipeline of hot junction and with the displacement of scavenging flexible member and slides; Phase modulation elasticity/quality component is installed in the room temperature pipeline, and its mass elements is contained in the pipeline and with the displacement of phase modulation flexible member and slides.Can be by adjusting to phase difference between pressure oscillation and volume flow fluctuation, recovery sound merit, and the circulation in inhibition loop reduce heat loss, improve the refrigeration machine performance.

Description

A kind of electricity driven traveling wave thermoacoustic refrigerator system

Technical field

The present invention relates to refrigeration and cryogenic technique field, particularly relate to a kind of electricity driven traveling wave thermoacoustic refrigeration system.

Background technology

For traditional travelling-wave type hot sound refrigerating machine, show by following equation from the sound merit of pressure wave generator input system:

$W=\frac{1}{2}\mathrm{Re}\left[\tilde{p}\widetilde{U^{*}}\right]=\frac{1}{2}\left|\tilde{p}\tilde{U}\right|\cos {\mathrm{\Φ}}_{\mathrm{pu}}=\frac{\mathrm{V\Ω}}{4}\left|\tilde{p}\right|\·\cos {\mathrm{\Φ}}_{\mathrm{pu}}---\left(1\right)$

(1) in the formula, Re[] represent the plural number in the square brackets is got real part, * represents complex conjugate, || expression is got amplitude to the plural number in this symbol,

And

Represent the fluctuation of pressure and volume flow respectively, Φ _PuPhase place angle between fluctuation of expression compression pressure and the volume velocity fluctuation, V represents the scavenging volume of pressure wave generator piston, Ω represents the compressor operating angular frequency.(1) in the formula, the sound merit of input system not only depends on the product of pressure amplitude and scavenging volume, angular frequency, also depends on phase difference between the two simultaneously.When actual motion since pressure oscillation and the volume flow phase difference between fluctuating near 90 °, so the sound merit of input system is very little, the ability of pressure wave generator is not utilized preferably.For instance, cos80 °=0.1736, and cos60 °=0.5, as seen obtained in the input of sound merit growth near 2 times in 20 ° raising on the phase place, at this moment, the sound merit demand for equivalent under the same frequency can adopt the less pressure wave generator of scavenging volume.This shows that the phase place of regulating pressure oscillation and volume flow fluctuation in the ripple hot sound refrigerating machine of being expert at has significance.

The utilization of phase modulation means is not only to be expert at just to occur in the ripple hot sound refrigerating machine, in the monoblock type sterlin refrigerator, as shown in Figure 5, drive motors is controlled phase difference between compression piston 7 and the phase modulation piston 16 by toggle 22, thus the refrigeration of realization.This is a kind of active phase modulating mechanism.The shortcoming of monoblock type sterlin refrigerator is: the motion phase between its compressor piston and the ejector piston needs the complicated mechanical motion to finish, between two pistons and the cylinder friction is arranged all, the motion that particularly is in the ejector piston under the low temperature has reduced the reliability of system widely, also can cause bigger loss and bigger mechanical oscillation simultaneously.Recently (this thermoacoustic system is made of a loop the capable ripple hot sound refrigerating machine that occurs as shown in Figure 4, be placed with two room temperature heat exchangers and a cool end heat exchanger in the loop, pressure wave is imported from a branch road), it is a kind of heat sound separated type sterlin refrigerator that does not have moving component at low temperatures, it comes the phase difference between the pressure wave and speed wave in the regulating loop by inertia tube 21 and acoustic capacitance, but the structure of this separated type has caused the phase place of pressure wave in the compression chamber of pressure wave generator and speed wave very near 90 °, causes the ability of compressor to be not in full use.

Summary of the invention

The objective of the invention is to solve travelling wave refrigerating device in the prior art utilizes inertia tube and acoustic capacitance to be difficult to regulate the problem of pressure wave and speed wave phase place in the compression chamber; Overcoming big sound merit demand needs big pressure wave generator, attracts the problem of making difficulty; Overcome the problem that the pressure wave generator of capable ripple hot sound refrigerating machine fails to be fully used.

Technical scheme of the present invention is as follows:

Electricity driven traveling wave thermoacoustic refrigerator system provided by the invention, comprise the cool end heat exchanger 1 that links to each other successively and form the loop, regenerator 2, heater 3, thermal buffer tube 4, hot end heat exchanger 5 and annular connecting pipe is characterized in that, comprise that also one is installed in the pressure wave generator in the annular connecting pipe;

Described pressure wave generator comprises: a cylinder type cylinder 23, these cylinder type cylinder 23 1 ends are communicated with the room temperature pipeline 18 that links to each other with cool end heat exchanger 1, other end opening, its openend is installed a sleeve pipe 24, described sleeve pipe 24 1 ends are sleeved on the outer wall of the hot junction pipeline 6 that links to each other with hot end heat exchanger 5 and closely cooperate, and the other end is provided with the circular central aperture; Fixed installation one has the Crossed Circle magnetic conductive soft iron 11 of annular cavity 111 in the cavity between cylinder type cylinder 23 and sleeve pipe 24, inlays the round ring magnet 10 of one section equal thickness in the outer ring magnet wall of described Crossed Circle magnetic conductive soft iron 11; The coil brace 14 that is wound with coil 12 on one barrel of wall is fixed on the inwall of described cylinder type cylinder 23, and its part that is wound with coil 12 is inserted in the annular cavity 111 of Crossed Circle magnetic conductive soft iron 11; An axle 30 that passes circular central aperture on the sleeve pipe 24 is fixed in the center of described coil brace 14; On the axle 30 in the circular central aperture linear slide bearing 9 is installed; One scavenging elasticity/quality component is installed in the described hot junction pipeline 6, this scavenging elasticity/quality component is made up of scavenging flexible member 8 that is connected with each other and mass elements 7, scavenging flexible member 8 links to each other with linear slide bearing 9 end faces, and mass elements 7 is installed in the hot junction pipeline 6 and with the elastic displacement of scavenging flexible member 8 and slides in hot junction pipeline 6; In the described room temperature pipeline 18 a phase modulation elasticity/quality component is installed, this phase modulation elasticity/quality component is made up of phase modulation flexible member 17 that is connected with each other and mass elements 16, described phase modulation flexible member 17 links to each other with coil brace 14 end faces, and described mass elements 16 is installed in the room temperature pipeline 18 and with the elastic displacement of phase modulation flexible member 17 and slides in room temperature pipeline 18.

Be communicated with a connecting pipe 26 between described room temperature pipeline 18 and the cylinder type cylinder 23, the gas valve 19 of the linear electric generator of balance when being used to charge and discharge a gas external and internal pressure was installed on communicating pipe 26.

Described scavenging elasticity-quality component can be spring-piston component, and its spring is a flexible member, and piston is a mass elements; Described spring can be the common helical spring that metal material spirals and forms, or does not produce the compression/extension spring that cutting forms on one section metal tube that rotatablely moves during compression/stretching.Described scavenging elasticity-quality component also can be bellows-mass assembly, and its bellows is a flexible member, and mass is a mass elements; Which floor described bellows stack the rigidity moulding bellows that welds together for, or for thin stainless steel substrates at the edge joint weld flexible bellow that is connected together.

Described phase modulation elasticity-quality component can be spring-piston component, and its spring is a flexible member, and piston is a mass elements; Described spring is the common helical spring that metal material spirals and forms, or does not produce the compression/extension spring that cutting forms on one section metal tube that rotatablely moves during compression/stretching; Described phase modulation elasticity-quality component also can be bellows-mass assembly, and its bellows is a flexible member, and mass is a mass elements; Which floor bellows in described bellows-mass assembly stack the rigidity moulding bellows that welds together for, or for thin stainless steel substrates at the edge joint weld flexible bellow that is connected together.

Electricity provided by the invention drives row ripple thermoacoustic refrigeration system compared with prior art, and its advantage is:

A) by the adjusting to phase difference between pressure oscillation and volume flow fluctuation, reclaimed the sound merit on the one hand, the sound merit that makes pressure wave generator produce under the scavenging volume of equivalent on the other hand increases, and the sound merit that has made full use of pressure wave generator produces ability;

B) pressure wave generator is placed capable ripple loop, suppressed the circulation in loop up hill and dale, reduced the heat loss that causes of circulation, thereby improved the performance of refrigeration machine;

C) replace inertia tube and the acoustic capacitance that is used for phase modulation in traditional travelling wave refrigerating device with the less elasticity-quality component of volume, helped the microminiaturization and the practicability of system.

Description of drawings

Fig. 1 is the structural representation that electricity provided by the invention drives row ripple thermoacoustic refrigeration system embodiment 1;

Fig. 2 is the structural representation that electricity provided by the invention drives row ripple thermoacoustic refrigeration system embodiment 2;

Fig. 3 is the structural representation that electricity provided by the invention drives row ripple thermoacoustic refrigeration system embodiment 3; Fig. 4 is a traditional hot sound travelling wave refrigerating device system architecture schematic diagram;

Fig. 5 is a monoblock type sterlin refrigerator structural representation.

Fig. 6 is two-freedom spring-damper-mass schematic diagram.

Fig. 7 is (cut out radial clearance on metal pipe-wall, the certain angle that staggers mutually pivots between the gap) novel mechanical spring.

The specific embodiment

Before the narration specific embodiment, at first phase modulation principle of the present invention is described as follows:

Fig. 6 is two degrees of freedom spring, damper quality system schematic diagram, as shown in the figure, k1 wherein, k2, k3 are respectively the stiffness coefficient of spring, c1, c2, c3 is respectively the damped coefficient of linear damping device, and then two degree freedom system is got by the system motion differential equation the steady-state response expression formula of simple harmonic quantity excitation:

$m_1{\stackrel{\·\·}{x}}_1=F_1\left(t\right)-c_1{\stackrel{\·}{x}}_1+c_2({\stackrel{\·}{x}}_2-{\stackrel{\·}{x}}_1)-k_1{x}_1+k_2(x_2-x_1)$

$m_2{\stackrel{\·\·}{x}}_2=F_2\left(t\right)-c_3{\stackrel{\·}{x}}_2-c_2({\stackrel{\·}{x}}_2-{\stackrel{\·}{x}}_1)-k_3{x}_2-k_2(x_2-x_1)$

(2)

If: F ₁(t)=F ₁e ^{I Ω t}, F ₂(t)=0, then can solve suitable steady-state response of the present invention is:

$x_1\left(t\right)=\frac{F_1{Z}_{22}\left(\mathrm{\Ω}\right)}{Z_{11}\left(\mathrm{\Ω}\right)Z_{22}\left(\mathrm{\Ω}\right)-Z_{12}^2\left(\mathrm{\Ω}\right)}\·e^{\mathrm{i\Ωt}}$

$x_2\left(t\right)=\frac{-F_1{Z}_{21}\left(\mathrm{\Ω}\right)}{Z_{11}\left(\mathrm{\Ω}\right)Z_{22}\left(\mathrm{\Ω}\right)-Z_{12}^2\left(\mathrm{\Ω}\right)}\·e^{\mathrm{i\Ωt}}$

(3)

Wherein: c ₁+ c ₂=c ₁₁,-c ₂=c ₁₂=c ₂₁, c ₂+ c ₃=c ₂₁

k ₁+k ₂＝k ₁₁，-k ₂＝k ₁₂＝k ₂₁，k ₂+k ₃＝k ₂₂

Z ₁₁(Ω)＝k ₁₁+iΩc ₃₁-m ₁Ω ²

Z ₁₂(Ω)＝k ₁₂+iΩc ₁₂

Z ₂₁(Ω)＝k ₂₁+iΩc ₂₁

Z ₂₂(Ω)＝k? ₂₂+iΩc ₂₂-m ₂Ω ²

(3) in the formula, comprised phase relation in the amplitude of x1 and x2.If be actuated to cosine, then get the real part of x1 and x2; Among the present invention, if be actuated to sine, the imaginary part of then getting x1 and x2.There are phase difference in steady-state response x1 and x2, and the rigidity that changes the size of two moving-mass and spring can change the phase difference size between x1 and the x2, and this makes that utilizing elasticity-mass assembly that row ripple hot sound refrigerating machine is carried out phase modulation becomes possibility.

The present invention will be further described below in conjunction with the specific embodiment and accompanying drawing:

Embodiment 1:

The structure of embodiment 1 comprises the room temperature heat exchanger 1 that links to each other successively, thermal buffer tube 2 as shown in Figure 1, cool end heat exchanger 3, the regenerator 4 that material web such as stainless steel or brass is filled, hot end heat exchanger 5 and annular connecting pipe also comprise the pressure wave generator that is installed in the circulating line.In the present embodiment, " U " shape connecting pipe 6 that pressure wave generator one termination is derived by hot end heat exchanger 5 is called hot junction pipeline 6 with this connecting pipe; " U " shape connecting pipe 18 that another termination is derived by concubine temperature heat exchanger 1 is called room temperature pipeline 18 with this connecting pipe.The effect of concubine temperature heat exchanger 1 and thermal buffer tube 2 is to prevent that the gas that vibrates back and forth from taking heat to cool end heat exchanger 3, increases the loss of cold.Cool end heat exchanger 3, regenerator 4, the assembly that hot end heat exchanger 5 is formed is the core component of hot sound refrigerating machine, it is characterized in that the sound merit is absorbed in regenerator 4, simultaneously owing to the thermoacoustic effect between gas medium and solid dielectric produces the pump heat effect, if gas medium in the temperature end heat release, keep hot end heat exchanger 5 for room temperature, at cool end heat exchanger 3 can obtain refrigerating capacity on the macroscopic view from the low-temperature end heat absorption.Pressure wave generator is the drive source of row ripple hot sound refrigerating machine, comprises a cylindric cylinder 23, and these cylinder 23 1 ends link to each other with room temperature pipeline 18, and other end opening is installed the round-meshed base plate 25 in a center on the end face of opening; One is fixedly mounted on the sleeve pipe 24 on the base plate 25, these sleeve pipe 24 1 end openings also extend radially outward at opening part, this extension is fixed on the sidewall and base plate 25 of cylinder 23, the other end sealing of sleeve pipe 24, an aperture is left in the center of its circular end surface, and opening one end of this sleeve pipe 24 is enclosed within on " U " shape hot junction pipeline 6 and closely cooperates with the outer wall of pipeline 6; One permanent magnet 10 and the magnetic conductive soft iron 11 that is positioned at its both sides, the magnetic material association that permanent magnet 10 and magnetic conductive soft iron 11 are formed is shaped as a side and is close to the rotary body that " U " shape face of cylinder 23 sidewalls rotates a circle and forms around cylinder 23 axis, this rotary body is formed by mutually nested interior pipe, outer tube and with the annular bottom surface that the two couples together, the sidewall of this magnetic material association and annular bottom surface be separately fixed on cylinder 23 sidewalls and the extension of sleeve pipe 24 opening parts on; One round barrel shape coil brace 14 is wound with coil 12 on its barrel wall, and inserts between the interior pipe and outer tube of magnetic material association; One comprises that a flexible member and a mass elements and its mass elements are positioned at the scavenging elasticity-quality component of hot junction pipeline 6, its flexible member one end is connected on the end face of mass elements, the other end is connected on the bottom surface of sleeve pipe 24, this elasticity-quality component is spring-piston component in the present embodiment, and its flexible member and mass elements are respectively support spring 8 and scavenging piston 7; One is positioned between the mass elements (being scavenging piston 7) of coil brace 14 and scavenging elasticity-quality component and with the two axle 30 that is connected mutually, be with linear slide bearing 9 on it, this linear slide bearing 9 is fixed on the aperture hole wall of sleeve pipe 24 bottom surfaces, and its effect is with the radial location of pressure wave generator mover part; One two ends are separately fixed at the support spring 13 on sleeve pipe 24 and the coil brace 14; One comprises that a flexible member and a mass elements and its mass elements are positioned at the phase modulation elasticity-quality component of room temperature pipeline 18, its flexible member one end is connected on the end face of mass elements, the other end is connected on the end face of coil brace 14, this elasticity-quality component is spring-piston component in the present embodiment, and its flexible member and mass elements are respectively mechanical spring 17 and phase modulation piston 16; One is communicated with the communicating pipe 26 of phase modulation piston 16 both sides cavitys; One was installed on communicating pipe 26, the gas valve 19 of the inside and outside average pressure of equalizing pressure wave producer when being used to charge and discharge gas.

In the pressure wave generator of present embodiment, coil brace 14 is connected by axle 30 mutually with scavenging piston 7, the mover of decomposition pressure wave producer, and it is radially by linear slide bearing 9 location.During work, alternating current is through sealed electrical joint 15 switch-on coils 12 (this coil can be formed by metal enamel conductor coilings such as brass and aluminum conductors), coil is subjected to the alternating electromagnetic force effect in the magnetic field that permanent magnet 10 and its both sides magnetic conductor 11 are gathered into, drive simultaneously with its coil brace that is fixed together 14, under the effect of mechanical support spring 8,13, produce vibration; Two support spring one ends maintain static, and the other end is connected with mover and scavenging piston 7 respectively; Scavenging piston produces oscillating movement, its right side gas that compresses and expand, thus produce pressure oscillation.In the regenerator under the pressure wave effect, thereby Working medium gas and solid dielectric produce thermoacoustic effect and obtain the pump fuel factor, heat by from cool end heat exchanger 3 pumps to hot end heat exchanger 5, if take away heat at hot end heat exchanger 5 places and keep room temperature, then can on cool end heat exchanger, obtain cold.The effect of phase modulation piston 16 pressurized Reebs produces vibration, also is stretched or compressed thereby connect spring 17 under driving, simultaneously because the effect of this spring has also influenced the motion of mover.There is phase difference in flexible member transmission campaign, thereby can finish the phase modulation of two moving-mass.One bypass pipe road (communicating pipe 26 that promptly has gas valve 19) is arranged, the average pressure when charging and discharging gas inside and outside the equalizing pressure wave producer between room temperature pipeline 18 and pressure wave generator.Two pistons all adopt the sealing of piston ring form.The mechanical spring of making in the present embodiment can adopt material spiral formings such as common carbon steel, 50 chrome alum, also can adopt special spring (as shown in Figure 7) as connecting spring, its manufacturing way is to cut out radial clearance on metal pipe-wall, the certain angle that staggers mutually pivots between the gap, in the time of effect that its advantage is to provide identical with the conventional helical spring, when Compression and Expansion, can not produce twist motion.The rigidity of quality size, cross-sectional area and spring by changing piston in the present embodiment can realize phase modulation in various degree.

Embodiment 2:

As shown in Figure 2, present embodiment adopts metal bellows 20 to replace the mechanical spring 17 among the embodiment 1, the phase modulation piston 16 that employing one mass 29 replaces embodiment 1 on the basis of embodiment 1; Simultaneously, adopted linear slide bearing or leaf spring to support this mass 29; On the end face of coil brace 14, increase gas passage, made secondary bellows can not produce too big pressure oscillation and damage bellows when internal gas vibrates when vibrating.The metal bellows of present embodiment can adopt materials such as common stainless steel 304, beryllium-bronze.Production method is shaped by fluid pressure or be welded normally.Usually, relatively welding bellows is bigger on rigidity for the bellows of shaped by fluid pressure, so stability is relatively good.

During work, metal bellows 20 plays the effect of mechanical spring 17 among the embodiment 1, and mass 29 plays the effect of phase modulation piston 16 among the embodiment 1, and other parts role and the course of work are all identical with embodiment 1, therefore no longer repeats.In the present embodiment, owing to adopt bellows 20 and mass 29, the phase modulation parts needn't carry out piston ring packing, thereby have reduced friction.

Embodiment 3:

The structure of present embodiment as shown in Figure 3, it is to transform to form on the basis of embodiment 2.Present embodiment has replaced spring-piston component among the embodiment 2 as scavenging elasticity-quality component with bellows-mass assembly, and the material of all the other parts is all identical with embodiment 2 with manufacture craft and connected mode thereof.This bellows-mass assembly is made up of metal bellows 28 and mass 27, and linear slide bearing 9 is connected with mass 27, plays a supporting role.

Claims (8)

1. electricity driven traveling wave thermoacoustic refrigerator system, comprise the cool end heat exchanger (1) that links to each other successively and form the loop, regenerator (2), heater (3), thermal buffer tube (4), hot end heat exchanger (5) and annular connecting pipe is characterized in that, comprise that also one is installed in the pressure wave generator in the annular connecting pipe;

Described pressure wave generator comprises: a cylinder type cylinder (23), these cylinder type cylinder (23) one ends are communicated with the room temperature pipeline (18) that links to each other with cool end heat exchanger (1), other end opening, its openend is installed a sleeve pipe (24), described sleeve pipe (24) one ends are sleeved on the outer wall of the hot junction pipeline (6) that links to each other with hot end heat exchanger (5) and closely cooperate, and the other end is provided with the circular central aperture; Fixed installation one has the Crossed Circle magnetic conductive soft iron (11) of annular cavity (111) in the cavity between cylinder type cylinder (23) and sleeve pipe (24), inlays the round ring magnet (10) of one section equal thickness in the outer ring magnet wall of described Crossed Circle magnetic conductive soft iron (11); The coil brace (14) that is wound with coil (12) on one barrel of wall is fixed on the inwall of described cylinder type cylinder (23), and its part that is wound with coil (12) is inserted in the annular cavity (111) of Crossed Circle magnetic conductive soft iron (11); An axle (30) that passes the circular central aperture on the sleeve pipe (24) is fixed in the center of described coil brace (14); On the axle (30) in the circular central aperture linear slide bearing (9) is installed; One scavenging elasticity/quality component is installed in the described hot junction pipeline (6), this scavenging elasticity/quality component is made up of scavenging flexible member (8) that is connected with each other and mass elements (7), scavenging flexible member (8) links to each other with linear slide bearing (9) end face, and mass elements (7) is installed in the hot junction pipeline (6) and with the elastic displacement of scavenging flexible member (8) and slides in hot junction pipeline (6); One phase modulation elasticity/quality component is installed in the described room temperature pipeline (18), this phase modulation elasticity/quality component is made up of phase modulation flexible member (17) that is connected with each other and mass elements (16), described phase modulation flexible member (17) links to each other with coil brace (14) end face, and described mass elements (16) is installed in the room temperature pipeline (18) and with the elastic displacement of phase modulation flexible member (17) and slides in room temperature pipeline (18).

2, by the described electricity driven traveling wave thermoacoustic refrigerator system of claim 1, it is characterized in that, be communicated with a connecting pipe (26) between described room temperature pipeline (18) and the cylinder type cylinder (23), go up the gas valve (19) that the linear electric generator of balance when being used to charge and discharge a gas external and internal pressure is installed communicating pipe (26).

3, by the described electricity driven traveling wave thermoacoustic refrigerator system of claim 1, it is characterized in that described scavenging elasticity-quality component is spring-piston component, its spring is a flexible member, and piston is a mass elements.

4, by the described electricity driven traveling wave thermoacoustic refrigerator system of claim 1, it is characterized in that described scavenging elasticity-quality component is bellows-mass assembly, its bellows is a flexible member, and mass is a mass elements.

5, by the described electricity driven traveling wave thermoacoustic refrigerator system of claim 1, it is characterized in that described phase modulation elasticity-quality component is spring-piston component, its spring is a flexible member, and piston is a mass elements.

6, by the described electricity driven traveling wave thermoacoustic refrigerator system of claim 1, it is characterized in that described phase modulation elasticity-quality component is bellows-mass assembly, its bellows is a flexible member, and mass is a mass elements.

7, by claim 3 or 5 described electricity driven traveling wave thermoacoustic refrigerator systems, it is characterized in that: the spring in described spring-piston component is the common helical spring that metal material spirals and forms, or does not produce cutting forms on one section metal tube compression/extension spring or the flat spring that rotatablely moves during compression/stretching.

8, by claim 4 or 6 described electricity driven traveling wave thermoacoustic refrigerator systems, it is characterized in that: which floor the bellows in described bellows-mass assembly stack the rigidity moulding bellows that welds together for, or for thin stainless steel substrates at the edge joint weld flexible bellow that is connected together.

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