CN104653331A - Free piston Stirling heat engine - Google Patents

Abstract

A free-piston Stirling heat engine comprises a cylinder body, a displacer arranged in the cylinder body, a power piston, and a linear oscillation motor; the power piston is composed of a piston plug body and a piston falcon part, and the piston plug body is arranged on the In the cylinder, the piston part is connected with the motor mover of the linear oscillating motor, an expansion chamber is formed between the displacer and the first end of the cylinder, a compression chamber is formed between the displacer and the power piston, and the outer circumference of the cylinder Spatial arrangement of heat-absorbing end heat exchangers, regenerators and heat-discharging end heat exchangers with a tube bundle structure that is not in contact with the cylinder; The mechanical damping and air leakage loss of the ejector; at the same time, it can effectively reduce the temperature of the room temperature side of the ejector, avoid increasing the mechanical damping of the ejector due to heat leakage, and even cause the ejector and cylinder to be stuck; Both the heater and the heat exchanger at the room temperature end adopt a small-diameter tube bundle structure, which can effectively reduce material requirements and manufacturing costs.

Description

A free piston Stirling heat engine

technical field

The invention relates to the technical field of thermal power, in particular to a free-piston Stirling heat engine.

Background technique

The free-piston Stirling heat engine is a special structural form of the thermoacoustic heat engine, which realizes the conversion between external heat and mechanical energy through the efficient Stirling cycle of the internal working medium. The free-piston Stirling engine using the forward Stirling cycle converts external heat energy into mechanical energy by expanding when heated, and compressing when it is cold; the free-piston Stirling refrigerator adopting the reverse Stirling cycle absorbs heat through expansion and releases heat through compression Heat is pumped from the low temperature side to the room temperature side to achieve cooling effect. Whether it is an engine or a refrigerator, the theoretical efficiency of this type of heat engine is equal to the Carnot efficiency. As a thermoacoustic heat engine, it realizes high-efficiency thermoacoustic or acoustothermal conversion through sound field phase modulation, and realizes efficient coupling with loads such as linear motors through sound field resonance and sound field coupling to build a free-piston Stirling generator Or an electrically driven free-piston Stirling refrigerator.

Benefiting from the characteristics of acoustic resonance, the free piston Stirling heat engine has no mechanical transmission mechanism and oil lubrication device inside, so it has the advantages of small vibration, simple structure and high reliability; it uses helium or nitrogen as the working fluid, and has the characteristics of environmental protection ; In addition, as an external combustion heat engine, it can use solar energy, industrial waste heat and biomass energy as heat sources, and has the advantages of wide applicability of heat sources and high comprehensive energy utilization rate. Based on the above characteristics, the free-piston Stirling heat engine has significant application prospects in the fields of solar power generation, waste heat power generation, and low-temperature refrigeration in the temperature range of minus 80 °C and below.

Although the free-piston Stirling heat engine has broad prospects, the traditional structure still has great limitations, which has become one of the important factors restricting the large-scale application of the heat engine. The following will combine the structural schematic diagram and working principle diagram to reveal its limitations.

Fig. 1 is a schematic structural diagram of an existing free-piston Stirling heat engine, which includes the following components: an expansion chamber 1, an internal heat exchanger 2 at the end heat end, an external heat exchanger 3 at the end heat end, a regenerator 4, a cylinder body 5, Heat exchanger 6 at the heat release end, compression chamber 7, power piston 8 (power piston plug body 8a, power piston falcon part 8b), linear oscillating motor 9 (motor mover 9b and motor stator 9a), planar support spring 10, motor Back chamber 11, ejector 12 (12a is the ejector rod body), ejector cylinder 13.

Fig. 2 is a schematic diagram of the working principle of the existing free-piston Stirling engine, and the components in Fig. 2 correspond to those in Fig. 1 . Please refer to Figure 1 and Figure 2 at the same time, taking the engine as an example, the working principle of the existing free-piston Stirling heat engine is as follows:

State a-state b process, the power piston 8 starts from the bottom dead center and moves up simultaneously with the ejector 12, so that the gas is compressed in the compression chamber 7 and releases heat to the outside through the heat exchanger 6 at the heat release end.

State b-state c process, the power piston 8 continues to move upward, the ejector 12 moves downward, the heat of the gas flows from the compression chamber 7 through the regenerator 4 and enters the expansion chamber 1, and the heat is released to the regenerator 4 on the way, and the temperature of the gas decreases.

State c-state d process, the gas in the expansion chamber 1 absorbs heat from the outside through the internal heat exchanger 2 and the external heat exchanger 3 and expands, causing the ejector 12 to go down and push the power piston 8 to go down. During this process, the regenerator 4 converts heat energy into sound energy (mechanical energy), and pushes the power piston 8 through the gas so that the mover 9b of the linear oscillation motor 9 cuts the magnetic force line and outputs it in the form of electric energy to the outside.

State d-state a process, the power piston 8 continues to go down, the ejector 12 goes up, the heat of the gas flows from the expansion chamber 1 through the regenerator 4 and enters the compression chamber 7, and releases the heat to the regenerator 4 on the way, and the temperature of the regenerator 4 As the temperature increases, the gas temperature decreases.

After completing the above-mentioned complete cycle process, the engine converts thermal energy into mechanical energy, and drives the mover 9b of the linear oscillating motor through the power piston 8 to cut the magnetic force line and output it in the form of electric energy to the outside. The power piston 8 and the ejector 12 do simple harmonic vibration, and the phase of the latter is ahead of the former.

Ideally, the heat that cannot be converted into energy (according to the second law of thermodynamics, generally about 2 to 3 times the power generation) and static heat leakage (retained from the high temperature area to the room temperature area through heat conduction, convection, and radiation) It should be taken away by the heat exchanger 6 at the discharge end, so as to ensure that the seal side of the ejector gap works at room temperature. In practice, due to the limitation of the structure and heat exchange conditions, the above two parts of heat cannot be effectively taken away by the heat exchanger 6 at the heat release end, which leads to the accumulation of heat on the sealing side of the ejector gap, making the ejector 12 and the ejector cylinder The mechanical damping between 13 increases, and in serious cases, the phenomenon of "stuck" will occur and cannot work.

The working principle of the displacer 12 of the free-piston Stirling heat engine can be expressed by the following formula:

mx″=P ₁ A ₁ -P ₂ A ₂ -Kx-Rx'

Among them, m is the mass of the ejector, x is the displacement of the ejector, x′ is the first derivative of displacement with respect to time, that is, velocity, x″ is the second derivative of displacement with respect to time, that is, acceleration, P ₁ and P ₂ are the displacement The two ends of the device are the pressure of the expansion chamber and the compression chamber, _A1 and _A2 are the cross-sectional areas of the two ends of the displacer respectively, K is the elastic coefficient of the planar support spring 10, and R is the damping coefficient.

It is not difficult to see from the formula that P ₁ A ₁ -P ₂ A ₂ is the driving force for the movement of the ejector, and once the mechanical damping R exceeds a threshold value, the resistance will exceed the driving force and the ejector cannot work.

On the other hand, it is not difficult to see from Fig. 1 that the regenerator 4 is adjacent to the ejector cylinder 13, and the filler of the regenerator 4 is generally piled wire mesh, fiber mat or random silk floss, while the ejector cylinder 13 is generally made of Thin wall stainless steel to reduce heat leakage. During the installation process, piled up silk screen or random silk floss can easily form a squeezing effect on the ejector cylinder 13, resulting in deformation of the ejector cylinder 13, resulting in serious air leakage loss or significantly increasing the mechanical damping of the ejector 12.

Finally, it should be pointed out that the regenerator 4 and the cylinder body 5 outside the internal heat exchanger 2 of the heat-absorbing end are generally made of thicker high-temperature alloy steel to ensure the safety of the system in the high-temperature and high-pressure internal environment. The greater the power of the engine, the greater the radial size and thickness of the cylinder block, and thus the higher the requirements for materials and manufacturing processes, which has become one of the important factors restricting the high-power and large-scale application of the free-piston Stirling engine .

Taking the free-piston Stirling engine as an example above, for the free-piston Stirling refrigerator, the traditional structure shown in Figure 1 also has the above-mentioned similar engine problems, including: the ejector and the ejector cylinder are stuck, and the ejector cylinder is deformed , Cylinder material and manufacturing process requirements are strict.

Contents of the invention

The purpose of the present invention is to provide a free-piston Stirling heat engine to simplify the structure of the heat exchanger at the heat release end, the regenerator and the heat exchanger at the heat absorption end, improve the reliability of the system, and reduce the process difficulty and manufacturing cost of the system. And it can overcome the defects of the above-mentioned free-piston Stirling heat engine that the ejector and the ejector cylinder are stuck, the ejector cylinder is deformed, the material of the cylinder body and the manufacturing process are strict, and the like.

Technical scheme of the present invention is as follows:

The purpose of the present invention is to provide a free-piston Stirling heat engine to simplify the structure of the heat exchanger at the heat release end, the regenerator and the heat exchanger at the heat absorption end, improve the reliability of the system, and reduce the process difficulty and manufacturing cost of the system. And it can overcome the defects of the above-mentioned free-piston Stirling heat engine that the ejector and the ejector cylinder are stuck, the ejector cylinder is deformed, the material of the cylinder body and the manufacturing process are strict, and the like.

Technical scheme of the present invention is as follows:

The free-piston Stirling heat engine provided by the present invention comprises a cylinder body, a displacer and a power piston arranged in the cylinder body, and a linear oscillating motor; the power piston is composed of a piston plug body and a piston falcon part, and the piston The plug body is arranged in the cylinder body, the piston falcon part is connected with the motor mover of the linear oscillating motor, an expansion chamber is formed between the ejector and the first end of the cylinder body, and the ejector and the first end of the cylinder body A compression chamber is formed between the power pistons, and it is characterized in that a tube bundle structure heat absorbing end heat exchanger, a tube bundle structure regenerator and a tube bundle structure exothermic heat exchanger that are not in contact with the cylinder body are arranged in the outer circumferential space of the cylinder body. end heat exchanger.

One end of the heat exchanger at the end of the tube bundle structure is connected to the expansion cavity, and the other end is connected to the regenerator.

One end of the heat exchanger at the discharge end of the tube bundle structure is connected with the compression chamber, and the other end is connected with the regenerator.

One end of the regenerator of the tube bundle structure is connected to the heat exchanger at the heat-absorbing end, and the other end is connected to the heat exchanger at the heat-discharging end.

The regenerator of the tube bundle structure, the heat exchanger at the end of the tube bundle structure and the heat exchanger at the discharge end of the tube bundle structure are the same or different in size and number of tube bundles, and there is a gap between the above three tube bundle structures. Corresponding relationship, that is, a heat regenerator with a tube bundle structure is connected to one or more heat absorbing end heat exchangers with a tube bundle structure and a heat release end heat exchanger with a tube bundle structure.

A planar support spring is arranged between the linear oscillating motor and the second end of the cylinder, and a motor back cavity is formed between the planar support spring and the second end of the cylinder.

The end of the ejector close to the power piston is also provided with an ejector rod, and the ejector rod is inserted into a through hole provided in the power piston.

The ejector rod body is fixedly connected with the planar support spring.

The linear oscillating motor and the power piston are arranged symmetrically along the rod body of the ejector.

Fins are provided on the outside of the heat-absorbing end heat exchanger of the tube bundle structure, the regenerator of the tube bundle structure or/and the heat-discharging end heat exchanger of the tube bundle structure; the material of the fins is copper or brass.

In the present invention, when used as an engine, the material of the heat-absorbing end heat exchanger can be high-temperature alloy steel or ordinary stainless steel according to different working temperature zones; when used as a refrigerator, the material of the heat-absorbing end heat exchanger 3 can be Available in copper or stainless steel.

In the present invention, the heat exchanger at the exothermic end is made of ordinary stainless steel or red copper.

In the present invention, the size and quantity of the regenerator can be the same as or different from that of the heat exchanger tube bundle at the end heat end and the heat exchanger tube bundle at the heat release end, and its material is ordinary stainless steel.

The advantage of the free-piston Stirling heat engine provided by the present invention is that by arranging the heat-absorbing end heat exchanger, the regenerator and the heat-discharging end heat exchanger in a tube bundle structure uniformly distributed in the circumferential direction and not in contact with the cylinder body, and The diameter of the round tubes of each component in the tube bundle structure is much smaller than that of the cylinder body, thereby effectively avoiding the problems of the ejector and the cylinder being stuck and the deformation of the cylinder, reducing the material of the cylinder body, manufacturing process requirements and manufacturing costs, and increasing system reliability. At the same time, in the free-piston Stirling heat engine provided by the present invention, the flow fields in the regenerator, the heat-absorbing heat exchanger and the heat-discharging heat exchanger are more uniform, the flow is smoother, and it can effectively restrain the The acoustic flow formed by symmetry etc. improves the system performance.

Description of drawings

Fig. 1 is a structural schematic diagram of an existing free-piston Stirling heat engine;

Fig. 2 is the working principle schematic diagram of existing free-piston Stirling heat engine (engine);

Fig. 3 is a schematic structural diagram of a free-piston Stirling heat engine provided by an embodiment of the present invention;

Fig. 4 is a schematic diagram of the working principle of the free-piston Stirling heat engine (engine) shown in Fig. 3;

Fig. 5 is a structural schematic diagram of a heat-absorbing end heat exchanger and a heat-releasing end heat exchanger of the present invention.

Detailed ways

In order to make the purpose, technical solutions and advantages of the present invention more clear, the present invention will be further described below in conjunction with the accompanying drawings and embodiments; obviously, the described embodiments are some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without making creative efforts belong to the protection scope of the present invention.

Fig. 3 is a schematic structural diagram of a free-piston Stirling heat engine provided by an embodiment of the present invention, and the same components in Fig. 3 and Fig. 1 are designated with the same reference numerals. As shown in Figure 3, the free-piston Stirling heat engine provided by this embodiment includes: a cylinder body 5, a linear oscillating motor 9, a power piston 8 and an ejector 12 arranged in the cylinder body 5; the power piston 8 includes a plug body 8a And the falcon part 8b, the plug body 8a is arranged in the cylinder body 5, the falcon part 8b is connected with the mover 9b of the linear oscillating motor 9; the expansion chamber 1 is formed between the ejector 12 and the first end of the cylinder body 5, and the ejector 12 is connected with the first end of the cylinder body 5. A compression chamber 7 is formed between the power pistons 8 .

Specifically, the end heat exchanger 3 of the free-piston Stirling heat engine provided in this embodiment is a tube bundle structure, preferably, it can be uniformly arranged in the circumferential direction outside the cylinder 5, it can be understood that for To enhance the heat exchange effect, a multi-layer fin structure can also be added on the outer wall of the tube bundle to increase the heat exchange area;

The heat exchanger 6 at the discharge end of the free-piston Stirling heat engine provided in this embodiment is a tube bundle structure. Preferably, it is uniformly arranged in the circumferential direction outside the cylinder 5. It can be understood that in order to enhance heat exchange As a result, a multi-layer fin structure can also be added on the outer wall of the tube bundle to increase the heat exchange area;

The regenerator 4 of the free-piston Stirling heat engine provided in this embodiment is a tube bundle structure, preferably, it is also uniformly arranged in the circumferential direction outside the cylinder body 5; one end of the regenerator 4 is connected to the end heat exchanger 3 are connected, and the other end is connected with the heat exchanger 6 at the exothermic end, and the tube bundle of the regenerator 4 is filled with layered screen, fiber felt or random silk floss.

The end of the ejector 12 close to the power piston 8 is further provided with an ejector rod body 12 a, and the ejector rod body 12 a is inserted into a through hole provided in the power piston 8 . The linear oscillating motor 9 includes a stator 9a and a mover 9b. The specific form of the linear oscillating motor 9 is not limited in this embodiment, and it can be a moving magnet type, a moving iron type, or a moving coil type.

The specific structure of the free-piston Stirling heat engine provided by the present invention will be further explained below in combination with the working principle of the free-piston Stirling heat engine. The following takes the working principle of the engine as an example, and the refrigerator is the reverse cycle of the engine. Fig. 4 is a schematic diagram of the working principle of the free-piston Stirling engine shown in Fig. 3 . Referring to Fig. 3 and Fig. 4 simultaneously, the operating principle of the free-piston Stirling engine provided by the present embodiment is as follows:

State a-state b process, the power piston 8 starts from the bottom dead center and moves upward at the same time as the ejector 12, so that the gas is compressed in the compression chamber 7 and releases heat to the outside through the heat exchanger 6 at the heat release end. The air or water passing through the tube bundle of the heat exchanger 6 at the exothermic end is taken away.

State b-state c process, the power piston 8 continues to move upward, the ejector 12 moves downward, the heat of the gas flows from the compression chamber 7 through the regenerator 4 and enters the expansion chamber 1, and the heat is released to the regenerator 4 on the way, and the temperature of the gas decreases.

State c-state d process, the gas in the expansion chamber 1 absorbs heat and expands from the outside through the heat-absorbing end heat exchanger 3, causing the ejector 12 to descend and push the power piston 8 to descend. During this process, the regenerator 4 converts heat energy into sound energy (mechanical energy), and pushes the power piston 8 through the gas so that the mover 9b of the linear oscillation motor 9 cuts the magnetic force line and outputs it in the form of electric energy to the outside.

State d-state a process, the power piston 8 continues to go down, the ejector 12 goes up, the heat of the gas flows from the expansion chamber 1 through the regenerator 4 and enters the compression chamber 7, and releases the heat to the regenerator 4 on the way, and the temperature of the regenerator 4 As the temperature increases, the gas temperature decreases.

After completing the above-mentioned complete cycle process, the heat energy is converted into mechanical energy, and the mover 9b of the motor is driven by the power piston 8 to cut the magnetic force lines and output to the outside in the form of electric energy. The power piston 9 and the ejector 12 do simple harmonic vibration, and the phase of the latter is ahead of the former. The working mechanism of the displacer and power piston in the free-piston Stirling heat engine provided in this embodiment is the same as that of the existing free-piston Stirling heat engine. However, the structural design and process characteristics of the free-piston Stirling heat engine provided by this embodiment are quite different from those of the prior art.

In the free-piston Stirling heat engine provided by this embodiment, the regenerator 4 is not a traditional annular structure, arranged outside the cylinder 5 and in contact with the cylinder 5, but a tube bundle structure, that is, the regenerator 4 consists of more than a dozen It is composed of hundreds of circular tubes, which are evenly arranged in the circumferential space outside the cylinder body 5 and do not contact the cylinder body 5 . The regenerator 4 that adopts small-diameter circular tube to form, its safety improves significantly compared with prior art.

The interior of the free-piston Stirling heat engine is high-pressure helium or nitrogen, and the gas pressure is generally 2MPa to 20MPa. For safe operation, the thickness of each component should meet the pressure resistance requirements. In particular, the stress of the circular tube at the regenerator 4 can be expressed by the following formula:

${\mathrm{<span\; class="notranslate">\; \&sigma;</span>}}_{\mathrm{<span\; class="notranslate">\; r</span>}}<span\; class="notranslate">\; =</span>\frac{\mathrm{<span\; class="notranslate">\; PD</span>}}{\mathrm{<span\; class="notranslate">\; 2</span>}\mathrm{<span\; class="notranslate">\; \&delta;</span>}}<span\; class="notranslate">\; \&le;</span>{\mathrm{<span\; class="notranslate">\; \&sigma;</span>}}_{\mathrm{<span\; class="notranslate">\; t</span>}}$

Among them, P is the gas pressure in the cylinder, D is the inner diameter of the cylinder, δ is the thickness of the cylinder, and _σt is the allowable stress of the cylinder material at the design temperature. It is not difficult to see from this expression that the smaller the inner diameter of the cylinder, the smaller the stress of the cylinder, and the more secure the pressure-resistant cylinder can be guaranteed.

It can be seen from the above pressure-resistant principle that the free-piston Stirling heat engine provided in this embodiment uses a small-diameter tube bundle to construct a regenerator, which can fully ensure the safety of the heat engine and improve the reliability of the heat engine. At the same time, its material cost and processing difficulty can be greatly reduced.

It should be noted that the tube bundle of the regenerator 4 is placed in the circumferential space outside the cylinder 5 , but it is not in contact with the cylinder 5 . Compared with the prior art, in the free-piston Stirling heat engine provided by this embodiment, the regenerator 4 will not squeeze the cylinder 5, so that the cylinder 5 will not be deformed and the ejector 12 will not be stuck with the cylinder 5. serious cases such as death.

In the free-piston Stirling heat engine provided by this embodiment, both the heat-absorbing heat exchanger 3 and the heat-discharging heat exchanger 6 adopt a tube bundle structure. The number and size of the tube bundles of the end heat exchanger 3, the regenerator 4, and the heat exchanger 6 at the heat release end may be the same or different, but there is a corresponding relationship between the three, that is, a regenerator with a tube bundle structure and a regenerator with a tube bundle structure The end heat exchanger of one or more tube bundle structures is connected to the heat exchanger of the heat release end of the tube bundle structure; refer to Figure 3, in this figure, a regenerator circular tube is connected to a heat absorption end heat exchanger circle tube and a heat exchanger round tube at the exothermic end, that is, 111 corresponds; The regenerator round pipe connection, that is, 212 combination, has many combinations, such as 313 combination, 414 combination, etc., which must be determined by the specific application. Compared with the existing technology, this arrangement method can ensure that the flow in each regenerator and heat exchanger tube is smoother, the flow field is more uniform, and the flow loss caused by irregular flow and the heat loss caused by acoustic flow are reduced. wait.

As a preferred implementation of this embodiment, a plane support spring 10 is also arranged between the linear oscillating motor 9 in the free piston Stirling heat engine and the second end of the cylinder body 5, and the plane support spring 10 is connected to the other end of the cylinder body 5 A motor back cavity 11 is formed between them, and the ejector rod body 12a is fixedly connected with the planar support spring 10 . The linear oscillating motor 9 and the power piston 8 are arranged symmetrically along the ejector rod body 12a. Since the radial stiffness of the planar support spring 10 is much greater than the axial stiffness, it can not only constrain the radial displacement of the ejector 12, prevent serious friction loss, but also enable the ejector 12 to have a large displacement in the axial direction ( Relative to the radial direction), to complete the compression and expansion of the gas.

As a preferred implementation manner, the interior of the regenerator 4 in this embodiment is filled with porous materials, such as stainless steel wire mesh, stainless steel fiber felt or stainless steel random silk floss. The ejector 12 can be a hollow closed cylindrical structure with equal cross-section or variable cross-section, the material can be stainless steel, and the cylindrical surface is thinner to reduce the axial heat conduction loss. The wall surface of the ejector 12 and the cylinder 5 adopts a gap seal to reduce the cross-gas and leakage heat loss between the expansion chamber 1 and the compression chamber 7 .

As an optional implementation manner of the foregoing embodiment, the structure of the heat exchanger may also be optimized. Fig. 5 is a schematic diagram of a heat exchanger provided by an embodiment of the present invention, and the same components in Fig. 5 and Fig. 3 use the same reference numerals. As shown in Fig. 5, the free-piston Stirling heat engine provided by this embodiment can specifically increase the heat exchange fins 14 on the outer surface of the tube bundle of the heat exchanger 3 at the heat-absorbing end and the tube bundle of the heat exchanger 6 at the heat-discharging end to significantly To increase the heat exchange area, the fins are made of copper or brass to improve thermal conductivity. The free-piston Stirling heat engine provided in this embodiment can be used in some specific working conditions.

Based on the above, in the free-piston Stirling heat engine provided by the present invention, the heat-absorbing end heat exchanger 3, the regenerator 4, and the heat-discharging end heat exchanger 6 all adopt a tube bundle structure, and are uniformly and non-contactly arranged in the cylinder block of the heat engine 5, the outer circumferential space, and the corresponding relationship between the three tube bundles, not only helps to improve system performance and power density, but also effectively reduces manufacturing costs, simplifies system structure, and increases system reliability.

Finally, it should be noted that: the above embodiments are only used to illustrate the technical solutions of the present invention, rather than limiting them; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: It is still possible to modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements for some or all of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the technical solutions of the various embodiments of the present invention. scope.

Claims (10)

1. a free piston stirling heat engine, it comprises cylinder body, is located at the discharger in cylinder body and power piston, and linear vibration motor; Described power piston is made up of piston cock body and piston falcon portion, described piston cock body is located in described cylinder body, described piston falcon portion is connected with the electric mover of described linear vibration motor, expansion chamber is formed between described discharger and described cylinder body first end, compression chamber is formed between described discharger and described power piston, it is characterized in that, described cylinder body outer circumference space is furnished with and described cylinder body discontiguous Pipe bundle structure heat absorbing end heat exchanger, Pipe bundle structure regenerator and Pipe bundle structure release end of heat heat exchanger.

2., by free piston stirling heat engine according to claim 1, it is characterized in that, one end of the heat absorbing end heat exchanger of described Pipe bundle structure is connected with expansion chamber, and the other end is connected with regenerator.

3., by free piston stirling heat engine according to claim 1, it is characterized in that, release end of heat heat exchanger one end of described Pipe bundle structure is connected with compression chamber, and the other end is connected with regenerator.

4. free piston stirling heat engine according to claim 1, is characterized in that, one end of the regenerator of described Pipe bundle structure is connected with heat absorbing end heat exchanger, and the other end is connected with release end of heat heat exchanger.

5. by free piston stirling heat engine according to claim 1, it is characterized in that, the regenerator of described Pipe bundle structure is restraining size with quantitatively identical or not identical again with the release end of heat heat exchanger of the heat absorbing end heat exchanger of Pipe bundle structure and Pipe bundle structure, and there is corresponding relation between above-mentioned three's Pipe bundle structure, namely the regenerator of a Pipe bundle structure is connected with the release end of heat heat exchanger of the heat absorbing end heat exchanger of one or more Pipe bundle structure and Pipe bundle structure.

6., by free piston stirling heat engine according to claim 1, it is characterized in that, between described linear vibration motor and described cylinder body second end, be provided with planar support spring, form motor between described planar support spring and described cylinder body second end and carry on the back chamber.

7., by free piston stirling heat engine according to claim 1, it is characterized in that, described discharger is also provided with the discharger body of rod near power piston one end, and the described discharger body of rod inserts in the through hole arranged in described power piston.

8., by free piston stirling heat engine according to claim 7, it is characterized in that, the described discharger body of rod is fixedly connected with described planar support spring.

9. free piston stirling heat engine according to claim 1, is characterized in that, described linear vibration motor and described power piston are symmetrical arranged along the described discharger body of rod.

10. free piston stirling heat engine according to claim 1, is characterized in that, the heat absorbing end heat exchanger of described Pipe bundle structure, the regenerator of Pipe bundle structure are or/and the outside of release end of heat heat exchanger of Pipe bundle structure is provided with fin; Described fin material is red copper or brass.