Oxygen-free Stirling engine unit

Abstract

The invention provides an oxygen-free Stirling engine unit, and belongs to the technical field of Stirling engines, the oxygen-free Stirling engine unit comprises a Stirling engine, a first heat pump and a second heat pump, the first heat pump is used for absorbing external low-grade energy and converting the external low-grade energy into high-grade energy, and the converted high-grade energy is conveyed to the Stirling engine through a first output pipeline set; the main power source serves as a main power source of the Stirling engine; the second heat pump is used for cooling the Stirling engine cooling cylinder through the energy recycling pipeline set and recycling energy exhausted by the Stirling engine to serve as an auxiliary power source of the Stirling engine. According to the anaerobic Stirling engine unit provided by the invention, the heat pump unit is used for absorbing low-grade energy discharged from the nature or industry to provide a power source for the Stirling engine, and fuel output power does not need to be consumed; the other heat pump is used for recycling energy exhausted by the Stirling engine to serve as an auxiliary power source of the Stirling engine, the heat efficiency of the engine is improved, and energy conservation and environment protection are facilitated.

Description

Technical Field

[0001] The invention belongs to the technical field of Stirling engines, and in particular relates to an oxygen-free Stirling engine group. Background Art

[0002] The Stirling engine outputs power through a cycle of cooling, compression, heat absorption, and expansion of the working medium in the cylinder, so it is also called a heat engine. The Stirling engine is an external combustion engine. Different fuels can provide heat sources for the Stirling engine. The thermal efficiency of the Stirling engine is between gasoline and diesel. However, each fuel needs oxygen to burn to release heat energy, consumes a lot of oxygen and releases a lot of carbon dioxide.

[0003] At present, the Stirling engine has the following disadvantages: (1) High requirements for materials: The maximum temperature of the gas in the internal combustion engine is much higher than that of the Stirling engine, but the internal combustion engine relies on heat dissipation to control the temperature of the cylinder at around 90°, while the heater and expansion chamber of the Stirling engine need to be maintained at a high temperature for a long time, which places high requirements on materials and also requires a large amount of fuel consumption.

[0004] (2) Large heat loss: Also because of maintaining high temperature for a long time, a lot of heat is lost through direct transfer and heat radiation, resulting in a large amount of energy waste and low fuel utilization.

[0005] Although the Stirling engine has many advantages over the internal combustion engine, such as being suitable for various energy sources, whether liquid, solid or gaseous fuel, having low noise during operation, and not being affected by air pressure, etc., with the shortage of energy in the global environment and the increasingly serious environmental protection situation, the current Stirling engine has the disadvantages of high fuel consumption, large heat loss, low fuel utilization rate and low efficiency, which is not conducive to the application and development of energy conservation and environmental protection. Summary of the invention

[0006] The embodiment of the present invention provides an oxygen-free Stirling engine group, which is intended to utilize low-grade energy to provide power for the Stirling engine. The engine itself does not require fuel consumption, and at the same time, the heat lost by the Stirling engine is recycled to improve the thermal efficiency of the engine.

[0007] To achieve the above object, the technical solution adopted by the present invention is: to provide an oxygen-free Stirling engine group, comprising: Stirling engine; a first heat pump, used for absorbing low-grade energy from the outside and converting it into high-grade energy, and transmitting the converted high-grade energy to the Stirling engine through a first output pipeline group as a main power source of the Stirling engine; and The second heat pump is used to cool the cold cylinder of the Stirling engine and recover the energy discharged by the Stirling engine through the energy recovery pipeline group, and is merged into the first output pipeline group through the second output pipeline group to serve as an auxiliary power source for the Stirling engine.

[0008] In one achievable manner, the Stirling engine includes one cylinder or a plurality of cylinders.

[0009] In one achievable manner, the Stirling engine includes two cylinders, a hot cylinder and a cold cylinder; the first output pipeline group is connected to the hot cylinder to provide a heat source for the hot cylinder; and the energy recovery pipeline group is connected to the cold cylinder to recover the heat energy discharged from the cold cylinder.

[0010] In one feasible manner, the hot cylinder and the cold cylinder are arranged radially, a first piston is provided in the hot cylinder, a second piston is provided in the cold cylinder, a movement direction of the first piston and a movement direction of the second piston are arranged at an angle, and a medium output pipeline is provided between the hot cylinder and the cold cylinder; a crankshaft-connecting rod mechanism is provided in the communication area between the hot cylinder and the cold cylinder, and the crankshaft-connecting rod mechanism includes a cam, a crankshaft eccentrically connected to the cam, a first connecting rod and a second connecting rod; one end of the first connecting rod is connected to the crankshaft, and the other end is rotatably connected to the first piston; one end of the second connecting rod is connected to the crankshaft, and the other end is rotatably connected to the second piston.

[0011] In one achievable manner, the Stirling engine includes a power cylinder and a third heat exchanger, a medium output pipeline is arranged between the power cylinder and the third heat exchanger; the high-grade energy converted by the first heat pump is transported to the third heat exchanger through the first output pipeline group, and the energy obtained by the third heat exchanger is supplied to the power cylinder through the medium output pipeline; a three-way valve is arranged on the medium output pipeline, the second heat pump absorbs the heat energy of the second heat exchanger through the energy recovery pipeline group, and the second heat exchanger is connected to the three-way valve through the medium energy recovery pipeline to recover the energy discharged from the power cylinder; the second heat pump is connected to the third heat exchanger through the second output pipeline group.

[0012] In one achievable manner, a medium circulation pipeline is provided between the second heat exchanger and the third heat exchanger, and a one-way valve is provided on the medium circulation pipeline.

[0013] In one achievable manner, the first heat pump absorbs low-grade energy from the outside through a first heat exchanger, and an energy input pipeline group is provided between the first heat pump and the first heat exchanger.

[0014] Compared with the prior art, the oxygen-free Stirling engine group provided by the present invention has the following beneficial effects: (1) A heat pump group absorbs low-grade energy in nature and converts it into high-grade energy to provide energy for the Stirling engine. This enables the Stirling engine to output power without consuming fuel, which is beneficial to energy conservation and environmental protection.

[0015] (2) Since this Stirling engine can utilize low-grade energy from nature and industrial waste through a heat pump, this energy does not require the consumption of oxygen during combustion and also reduces the pollution to the environment caused by the release of carbon dioxide.

[0016] (3) Another heat pump is used to cool the cold cylinder of the Stirling engine and recover the energy lost or discharged by the Stirling engine. As an auxiliary power source of the Stirling engine, it realizes further energy recovery and utilization, greatly reduces energy waste, improves the thermal efficiency of the engine, is beneficial to energy conservation and environmental protection, and is more conducive to the application and development of the Stirling engine. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 A schematic structural diagram of an oxygen-free Stirling engine group (two-cylinder radial arrangement) provided in an embodiment of the present invention; Figure 2 A schematic structural diagram of an oxygen-free Stirling engine group (single cylinder) provided in an embodiment of the present invention; Description of reference numerals: 1. First heat pump; 2. Second heat pump; 3. First heat exchanger; 4. First output pipeline group; 5. Second output pipeline group; 6. Crankshaft; 7. Second connecting rod; 8. Hot cylinder; 9. Cold cylinder; 10. Energy recovery pipeline group; 11. Energy input pipeline group; 12. Medium output pipeline; 13. First connecting rod; 14. Cam; 15. Power cylinder; 16. Medium energy recovery pipeline; 17. Three-way valve; 18. Second heat exchanger; 19. Third heat exchanger; 20. One-way valve; 21. Medium circulation pipeline. DETAILED DESCRIPTION

[0018] In order to make the technical problems, technical solutions and beneficial effects to be solved by the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0019] Please also read Figure 1 to Figure 2, the oxygen-free Stirling engine group provided by the present invention is now described. The oxygen-free Stirling engine group includes: a Stirling engine, a first heat pump 1 and a second heat pump 2. The first heat pump 1 is used to absorb low-grade energy from the outside and convert it into high-grade energy, and transmit the converted high-grade energy to the Stirling engine through the first output pipeline group 4, as the main power source of the Stirling engine; the second heat pump 2 is used to cool the cold cylinder of the Stirling engine through the energy recovery pipeline group 10 and recover the energy discharged by the Stirling engine, and is merged into the first output pipeline group 4 through the second output pipeline group 5, as the auxiliary power source of the Stirling engine.

[0020] The working process of the present invention is as follows: the first heat pump 1 absorbs energy output from low-grade heat sources such as air and water as the heat source of the Stirling engine, heats the hot cylinder 8 of the Stirling engine or heats the medium gas through a heat exchanger, and the medium gas expands to push the piston to do work. The second heat pump 2 cools the cold cylinder 9 of the Stirling engine and recovers the energy of the medium gas discharged after the Stirling engine does work. The heat energy output of the second heat pump 2 is incorporated into the output end of the first heat pump 1, and together with the energy output from the output end of the first heat pump 1, jointly pushes the Stirling engine to do work. The cylinders of the Stirling engine and the cylinders and the third heat exchanger 19 are connected by pipelines and valves to circulate or heat the gas medium. The opening or closing of the valve is controlled by the crankshaft 6, the cam 14, the connecting rod or the solenoid valve.

[0021] Compared with the prior art, the oxygen-free Stirling engine group provided by the present invention has the following beneficial effects: (1) A heat pump group absorbs low-grade energy and converts it into high-grade energy to provide a heat source for the Stirling engine. This enables the Stirling engine to output power without consuming fuel, which is beneficial to energy conservation and environmental protection.

[0022] (2) Since the Stirling engine can utilize low-grade energy from nature or industrial waste through a heat pump, this energy does not require combustion and consumes oxygen, and also reduces the pollution to the environment caused by the release of carbon dioxide.

[0023] (3) Another heat pump is used to recover the energy lost or discharged by the Stirling engine as an auxiliary power source of the Stirling engine, thereby realizing further energy recovery and utilization, greatly reducing energy waste, improving the thermal efficiency of the engine, and being beneficial to energy conservation and environmental protection, and more conducive to the application and development of the Stirling engine.

[0024] This application finds a way for the Stirling engine to utilize low-grade energy through the combination of a heat pump and a Stirling engine, which not only reduces energy consumption but also reduces the pollution of the atmosphere by exhaust gas emissions. It also reduces the thermal pollution to the environment caused by the emitted heat by absorbing the heat emitted by different equipment. It also improves the energy utilization efficiency and reduces the thermal pollution to the environment caused by the heat emitted by the engine itself by recovering the energy emitted by the engine itself through the heat pump.

[0025] The heat pump used in this application is a device that converts low-grade energy into high-grade energy. In recent years, heat pump technology and products have gradually matured, and the energy input-output ratio of heat pumps has reached 1:4-7. Moreover, in the environment where humans live, a large number of air conditioners and fans cool the environment, and most of the consumed electricity is discharged into the atmosphere in the form of heat energy. The temperature of geothermal, air and water in summer is high all year round, and the waste heat of industrialized factories is discharged into the atmosphere. These heat energies are low-grade energy and have a very low utilization rate. These low-grade energy sources can all be converted by heat pumps, thereby providing a stable source of energy for Stirling engines.

[0026] The feasibility of using a heat pump to absorb low-grade energy to provide energy for a Stirling engine is discussed in the present application as follows: Currently, the thermal efficiency of a Stirling engine is between gasoline and diesel, at around 0.4. Based on the thermal efficiency of the Stirling engine and the energy input-output ratio of the heat pump, it can be calculated that for every energy unit invested, the heat pump can output 4-7 energy units. Based on the heat pump input-output ratio of 5, the output end of the heat pump is used as the heat source of the Stirling engine. For every 5 energy units input into the Stirling engine, the Stirling engine can output 5 energy units × the thermal efficiency of the Stirling engine 0.4 = 2 energy units. Subtract one energy unit invested by the heat pump, and there is one energy unit left. This calculation result shows that it is feasible to use a heat pump to absorb low-grade energy such as air, water, and soil as a heat source for a Stirling engine to output kinetic energy.

[0027] For ease of understanding, the present application further describes the Stirling engine and the heat pump as follows: 1. Stirling engine A Stirling engine requires a heat source and a cold source. The heat source can be heat energy provided by combustion or other means, and the cold source can be ambient air or other cooling media.

[0028] Take the example of a Stirling engine with two cylinders, each with a piston. One cylinder is hot and the other is cold. The pistons reciprocate in the cylinders. The two pistons are connected by a connecting rod and a crankshaft; when the pistons move, the connecting rod converts the linear motion of the pistons into the rotational motion of the crankshaft.

[0029] The working principle of the Stirling engine is based on a cycle of heating, expansion, cooling and compression. The specific working process is as follows: Exhaust: At the beginning, both pistons are in their respective positions. The piston in the hot cylinder moves up, and the piston in the cold cylinder moves down. This can exhaust the residual gas in the cylinder.

[0030] Heating: The piston in the hot cylinder is pushed by the expanding gas to move, and the piston in the cold cylinder is passively moved to expel the gas. In this process, the heat energy is transferred to the hot cylinder through the heat exchanger, causing the high-temperature gas to expand, increasing the pressure to push the piston to move and convert the heat energy into kinetic energy to do work.

[0031] Expansion: The expansion of the hot gas pushes the piston in the hot cylinder down and the piston in the cold cylinder up. This converts part of the thermal energy into mechanical energy. This process is the main working process of the Stirling engine.

[0032] Cooling: After the expansion process, the high-temperature gas flows to the cold cylinder through the cold heat exchanger and transfers part of the heat energy to the low-temperature gas. After the high-temperature gas cools, its pressure and temperature drop, generating suction to move the piston.

[0033] Compression: The piston in the cold cylinder continues to move upward, and the piston in the hot cylinder continues to move downward, compressing the gas into the cold cylinder. In this process, the low-temperature gas will become colder and its volume will decrease, attracting the cold cylinder piston to move.

[0034] The whole cycle is carried out continuously, constantly absorbing heat from the heat source and converting part of the heat into mechanical energy. The Stirling engine does not require combustion, so there are no parts such as spark plugs and cylinder heads, which makes it have the advantages of low noise, low vibration and no emissions.

[0035] 2. Heat Pump Heat pump is an efficient energy utilization technology that absorbs heat from the natural environment and then transfers it to the space or medium that needs to be heated. The core principle of heat pump is to use the heat pump cycle to absorb the heat of the low-temperature heat source in the evaporator through the refrigerant (also called refrigerant or working medium), and then release the heat in the condenser to achieve heat transfer.

[0036] Heat pump is a highly efficient energy-saving device that fully utilizes low-grade thermal energy and can convert low-grade energy into high-grade energy. The working principle of heat pump is a mechanical device that forces heat to flow from low-temperature objects to high-temperature objects in a reverse cycle. It consumes only a small amount of reverse cycle net work to obtain a large amount of heat supply, and can effectively utilize the difficult-to-use low-grade thermal energy to achieve energy saving. Heat pump is different from the familiar mechanical equipment that can increase potential energy - "pump"; heat pump usually obtains low-grade thermal energy from natural air, water or soil, and then provides people with usable high-grade thermal energy through electricity.

[0037] The energy absorbed by the heat pump includes but is not limited to low-grade heat sources such as air, water, and industrial waste energy.

[0038] In some embodiments, see Figure 1 to Figure 2 As shown, the Stirling engine includes one cylinder or multiple cylinders. Multiple cylinders include but are not limited to two cylinders, four cylinders, 16 cylinders, etc.

[0039] In some embodiments, see Figure 1 and Figure 2 As shown, the Stirling engine includes two cylinders, a hot cylinder 8 and a cold cylinder 9. The first output pipeline group 4 is connected to the hot cylinder 8 to provide a heat source for the hot cylinder 8; the energy recovery pipeline group 10 is connected to the cold cylinder 9 to recover the heat energy discharged from the cold cylinder 9.

[0040] When the Stirling engine has four cylinders, the first heat pump 1 is connected to the first cylinder, and the second heat pump 2 can be connected to the second cylinder, the third cylinder and the fourth cylinder respectively through the parallel energy recovery pipeline group 10.

[0041] In some embodiments, see Figure 1 As shown, the hot cylinder 8 and the cold cylinder 9 are arranged radially, a first piston is provided in the hot cylinder 8, and a second piston is provided in the cold cylinder 9. The movement direction of the first piston and the movement direction of the second piston are arranged at an angle, and a medium output pipeline 12 is provided between the hot cylinder 8 and the cold cylinder 9; a crankshaft connecting rod mechanism is provided in the connecting area between the hot cylinder 8 and the cold cylinder 9, and the crankshaft connecting rod mechanism includes a cam 14, a crankshaft 6 eccentrically connected to the cam 14, a first connecting rod 13 and a second connecting rod 7; one end of the first connecting rod 13 is connected to the crankshaft 6, and the other end is rotatably connected to the first piston; one end of the second connecting rod 7 is connected to the crankshaft 6, and the other end is rotatably connected to the second piston.

[0042] The working principle of the above embodiment is as follows: the first heat pump 1 absorbs energy from low-grade heat sources such as air and water through the first heat exchanger 3 connected to the energy input pipeline group 11, and then heats the hot cylinder 8 of the Stirling engine through the first output pipeline group 4. The first piston compresses and does work, and pushes the cam 14 to rotate through the first connecting rod 13. The cam 14 drives the second connecting rod 7 to swing, and the second connecting rod 7 drives the second piston to move; the second heat pump 2 absorbs the heat energy of the cold cylinder 9 of the Stirling engine through the energy recovery pipeline group 10, and is merged into the first output pipeline group 4 through the second output pipeline group 5 to supply auxiliary heat energy to the Stirling engine.

[0043] Combination Figure 2 It is understood that the Stirling engine provided in this embodiment has one cylinder. Specifically, the Stirling engine includes a power cylinder 15 and a third heat exchanger 19. A medium output pipeline 12 is provided between the power cylinder 15 and the third heat exchanger 19. The high-grade energy converted by the first heat pump 1 is transported to the third heat exchanger 19 through the first output pipeline group 4. The energy obtained by the third heat exchanger 19 is supplied to the power cylinder 15 through the medium output pipeline 12. A three-way valve 17 is provided on the medium output pipeline 12. The second heat pump 2 absorbs the heat energy of the second heat exchanger 18 through the energy recovery pipeline group 10. The second heat exchanger 18 is connected to the three-way valve 17 through the medium energy recovery pipeline 16 to recover the energy discharged from the power cylinder 15. The second heat pump 2 transports the recovered energy to the third heat exchanger 19 through the second output pipeline group 5.

[0044] The working process of this embodiment is as follows: the first heat pump 1 is connected to the first heat exchanger 3 through the energy input pipeline group 11, absorbs heat energy from low-grade heat sources such as air and water, and the first heat pump 1 outputs heat energy to the third heat exchanger 19 through the first output pipeline group 4 to heat the medium gas of the Stirling engine. The medium gas of the Stirling engine enters the power cylinder 15 through the medium output pipeline 12 and the three-way valve 17 to push the piston to do work; when the hot medium gas in the power cylinder 15 fills the power cylinder 15, the medium output pipeline 12 between the power cylinder 15 and the third heat exchanger 19 is closed, and at the same time, the medium energy recovery pipeline 16 between the power cylinder 15 and the second heat exchanger 18 is opened, and the medium gas enters the second heat exchanger 18; when the medium gas pressure in the second heat exchanger 18 exceeds the medium gas pressure in the third heat exchanger 19, the medium gas opens the one-way valve 20 and enters the third heat exchanger 19 to complete the circulation of the medium gas. The energy input end of the second heat pump 2 is connected to the second heat exchanger 18 through the energy recovery pipeline group 10, absorbs the medium gas energy in the second heat exchanger 18, and outputs the combined energy to the first output pipeline group 4 through the second output pipeline group 5, providing an auxiliary power source for the Stirling engine.

[0045] Among them, the heat exchanger is a device for exchanging heat between high-temperature gas and low-temperature gas.

[0046] In some embodiments, see Figure 2 As shown, a medium circulation pipeline 21 is provided between the second heat exchanger 18 and the third heat exchanger 19 , and a one-way valve 20 is provided on the medium circulation pipeline 21 .

[0047] In some embodiments, see Figure 1 and Figure 2 As shown, the first heat pump 1 absorbs low-grade energy from the outside through the first heat exchanger 3 , and an energy input pipeline group 11 is arranged between the first heat pump 1 and the first heat exchanger 3 .

[0048] In the above embodiments, the description of each embodiment has its own emphasis. For parts that are not described or recorded in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0049] The above description is only a simple embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. An oxygen-free Stirling engine unit, characterized in that: include: Stirling engine; A first heat pump (1) is used to convert absorbed external low-grade energy into high-grade energy, and transmit the converted high-grade energy to the Stirling engine through a first output pipeline group (4) to serve as a main power source of the Stirling engine; and The second heat pump (2) is used to cool the cold cylinder of the Stirling engine and recover the energy discharged by the Stirling engine through the energy recovery pipeline group (10), and is merged into the first output pipeline group (4) through the second output pipeline group (5) to serve as an auxiliary power source for the Stirling engine.

2. The oxygen-free Stirling engine block according to claim 1, characterized in that: The Stirling engine comprises one cylinder or a plurality of cylinders.

3. The oxygen-free Stirling engine block according to claim 2, characterized in that: The Stirling engine comprises two cylinders, a hot cylinder (8) and a cold cylinder (9); the first output pipeline group (4) is connected to the hot cylinder (8) to provide energy for the hot cylinder (8); and the energy recovery pipeline group (10) is connected to the cold cylinder (9) to recover heat energy discharged from the cold cylinder (9).

4. The oxygen-free Stirling engine block according to claim 3, characterized in that: The hot cylinder (8) and the cold cylinder (9) are arranged radially, a first piston is arranged in the hot cylinder (8), and a second piston is arranged in the cold cylinder (9), the movement direction of the first piston and the movement direction of the second piston are arranged at an angle, and a medium output pipeline (12) is arranged between the hot cylinder (8) and the cold cylinder (9); a crankshaft (6) connecting rod mechanism is arranged in the connecting area between the hot cylinder (8) and the cold cylinder (9), and the crankshaft (6) connecting rod mechanism includes a cam (14), a crankshaft (6) eccentrically connected to the cam (14), a first connecting rod (13) and a second connecting rod (7); one end of the first connecting rod (13) is connected to the crankshaft (6), and the other end is rotatably connected to the first piston; one end of the second connecting rod (7) is connected to the crankshaft (6), and the other end is rotatably connected to the second piston.

5. The oxygen-free Stirling engine block according to claim 2, characterized in that: The Stirling engine comprises a power cylinder (15) and a third heat exchanger (19), wherein a medium output pipeline (12) is arranged between the power cylinder (15) and the third heat exchanger (19); the high-quality energy converted by the first heat pump (1) is transported to the third heat exchanger (19) through the first output pipeline group (4), and the energy obtained by the third heat exchanger (19) is supplied to the power cylinder (15) through the medium output pipeline (12); a three-way valve (17) is arranged on the medium output pipeline (12); the second heat pump (2) absorbs the heat energy of the second heat exchanger (18) through the energy recovery pipeline group (10), and the second heat exchanger (18) is connected to the three-way valve (17) through the medium energy recovery pipeline (16) to recover the heat energy discharged from the power cylinder (15); the second heat pump (2) is connected to the heat exchanger (19) through the second output pipeline group (5).

6. The oxygen-free Stirling engine block according to claim 5, characterized in that: A medium circulation pipeline (21) is provided between the second heat exchanger (18) and the third heat exchanger (19), and a one-way valve (20) is provided on the medium circulation pipeline (21).

7. The oxygen-free Stirling engine block according to claim 1, characterized in that: The first heat pump (1) absorbs low-grade energy from the outside through the first heat exchanger (3), and an energy input pipeline group (11) is provided between the first heat pump (1) and the first heat exchanger (3).

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