CN117759512A - An energy storage type ocean temperature difference energy underwater conversion device - Google Patents

Abstract

The invention discloses an energy-storage type ocean temperature difference energy underwater conversion device, which comprises: a heat source pump for providing ocean surface temperature seawater; the cold energy transport bin is used for providing deep ocean cold sea water; the cold energy transportation bin comprises a gas-liquid phase change cavity, an oil storage cavity and an elastic oil bag, and the oil storage cavity is communicated with the elastic oil bag; the gas-liquid phase change cavity comprises a phase change material cavity and a first balance cavity, and the oil storage cavity comprises an oil cavity and a second balance cavity; when the volume of the oil cavity is increased, the elastic oil bag is contracted, and the buoyancy of the cold energy transportation bin is reduced; when the volume of the oil cavity is reduced, the elastic oil bag is increased, and the buoyancy of the cold energy transportation bin is increased; the power generation bin is anchored on the seabed and provides a running track for the cold energy transport bin. The invention provides an energy storage type ocean temperature difference energy underwater conversion device, which is a novel solution to the problem of energy supply of an underwater autonomous vehicle working in a long self-sustaining large sea area.

Description

An energy storage type ocean temperature difference energy underwater conversion device

Technical field

The invention relates to the technical field of energy supply for autonomous underwater vehicles, and in particular to an energy storage type ocean temperature difference energy underwater conversion device.

Background technique

The autonomous underwater vehicle is a device that can monitor and detect underwater conditions. It is a high-tech marine equipment that all maritime powers are competing to develop. It is also the development focus of my country's construction of a maritime power. It is widely used in marine environmental surveys, seabed Resource surveying and other fields. At this stage, the energy required by autonomous underwater vehicles mainly relies on self-contained battery packs. The limited power source results in short mission schedules (less than one week), narrow working sea areas (hundred kilometers), and shallow working depths (kilometers). level) and high loss rate (more than 40%). Finding a safe and reliable sustainable energy supply solution is the key to solving the above problems.

As the only renewable ocean energy that can be captured and converted on-site by autonomous underwater vehicles in the deep sea, ocean thermoelectric power generation technology is the most feasible solution to the long-term energy supply problem of autonomous underwater vehicles. The existing ocean temperature difference energy-driven aircraft power system converts thermal energy into hydraulic oil pressure energy through the melting and expansion process of solid-liquid phase change materials in warm seawater areas, realizing the capture of ocean temperature difference energy, and the thermal energy-pressure energy of the solid-liquid phase change process. The conversion efficiency is only 0.7%, which greatly limits the thermoelectric conversion efficiency of this technology. Thermodynamic cycle power generation transfers the temperature difference energy to the circulating working fluid through a heat exchanger to capture the ocean temperature difference energy. The theoretical efficiency of this process is 100%, so this technology has higher thermoelectric conversion efficiency. However, currently, ocean temperature difference energy is mainly used to build large-scale megawatt power generation platforms, and the existing ocean temperature difference energy thermal cycle power generation platform transports cold seawater through cold seawater pipelines, which limits its use in autonomous underwater vehicles. application, and the power consumption of the cold seawater pump causes excessive self-consumption of the system, reducing the net output power of the thermoelectric power generation system. Eliminating or reducing the power consumption during the transportation of deep seawater cold energy will have significant benefits in increasing the net power generation of ocean thermoelectric power generation devices. Intermittent autonomous ascent and submergence cold energy transmission is the preferred solution for cold energy supply. In practical applications, it is affected by ocean currents and diving depth, and it is difficult to solve the problems of inconvenient communication and inaccurate positioning. In addition, there is no good solution yet for how to realize independent docking and cold energy transfer between cold energy transport equipment and components that require cooling in the power generation thermodynamic cycle. Therefore, fixing the motion trajectory of the autonomous submersible equipment, constructing a convenient communication method with the power generation warehouse, and designing a low-energy consumption and high-efficiency cold energy transfer mode are essential for incorporating the intermittent autonomous submergence cold energy transport scheme into practical applications. of great significance. Finally, the energy storage and transportation process of a single cold energy transportation equipment often takes a lot of time, resulting in the intermittent power generation process of ocean thermoelectric energy using the power-free cold source transportation mode, and the time efficiency of producing electric energy is not high. . Therefore, shortening the time interval between the previous and later power generation processes can greatly increase the power output of the power generation system per unit time.

Summary of the invention

The technical problem to be solved by the present invention is to provide an energy storage type underwater conversion device for ocean temperature difference energy with a non-powered submersible cold energy transport cabin as the core.

In order to solve the above technical problems, the present invention provides the following technical solutions:

An energy storage type ocean temperature difference energy underwater conversion device, including:

Heat source pump, used to provide ocean surface temperature seawater;

The cold energy transport warehouse is used to provide deep cold seawater in the ocean; the cold energy transport warehouse includes a gas-liquid phase change chamber, an oil storage chamber and an elastic oil bag, and the oil storage chamber is connected with the elastic oil bag; the gas The liquid phase change chamber includes a phase change material chamber and a first balance chamber, and the oil storage chamber includes an oil chamber and a second balance chamber; a linkage mechanism is provided between the gas-liquid phase change chamber and the oil storage chamber. When the volume of the phase change material in the phase change material cavity increases or decreases due to the evaporation-condensation process of the phase change material cavity, the linkage mechanism causes the volume of the oil cavity to increase or decrease simultaneously; when the volume of the oil cavity increases, When the elastic oil bladder shrinks, the buoyancy of the cold energy transport bin decreases and dives; when the volume of the oil chamber shrinks, the elastic oil bladder increases, and the buoyancy of the cold energy transport bin increases and rises;

A power generation warehouse that uses the temperature difference between the warm seawater on the ocean surface provided by the heat source pump and the cold seawater in the deep ocean provided by the cold energy transport warehouse to generate electricity and store it;

as well as

A multifunctional anchoring structure anchors the power generation warehouse to the seabed and provides an operating track for the cold energy transport warehouse.

The energy storage type ocean temperature difference energy underwater conversion device of the present invention uses the temperature difference between ocean surface seawater and deep seawater as the driving force. The ocean temperature difference energy is less affected by climate and environment, so the device can achieve continuous power output. The cold energy transport warehouse transports cold energy through the periodic condensation-evaporation process of gas-liquid phase change materials between the seabed and the sea surface, and uses the volume changes caused by the gas-liquid phase change process to achieve unpowered lifting of the cold energy transport warehouse. Submersible, it overcomes the shortcomings of high energy consumption of traditional thermoelectric power generation and cold seawater pumps. Secondly, the device broadens the functional scope of the mooring structure, using the mooring structure as a transport guide rail for the cold energy transport warehouse, constraining the submergence route of the cold energy transport warehouse, and ensuring the reliability and safety of cold energy transport. . By arranging two upper and lower magnetic interfaces on the surface of the cold energy transport bin, the device realizes the use of pressurized positive feedback of the phase change process to push the liquid phase change material into the components that require cooling in the closed power generation thermodynamic cycle structure, minimizing the need for cooling. The power consumption of the cold source pump. At the same time, by arranging several alternately working cold energy transport bins on the transport guide rails, the time interval of the thermodynamic cycle power generation process is shortened. Finally, the device generates electricity based on a closed power generation thermodynamic cycle structure. The generated electric energy is stored in the battery and provides power for autonomous underwater cruisers working in the deep sea through the magnetic charging port. This device can not only eliminate the defect that the power supply distance is limited by the length of the submarine cable, but also has good concealment.

The multifunctional anchoring structure includes a mooring rope, an anchor concrete block and a transport guide rail; the anchor concrete block is fixed on the seabed, and is connected to the power generation warehouse through the mooring rope to play a positioning role; the The mooring rope is relatively fixed to the transport guide rail, providing a fixed running trajectory for the cold energy transport bin and constraining the ascent and submergence route of the cold energy transport bin.

The electric energy generated by the power generation cabin is stored in the battery, and power supply is provided for the autonomous underwater vehicle through the magnetic charging interface of the power generation cabin.

The working fluid used in the closed loop can be, but is not limited to, R245fa, R134a, R1233zd(E), ammonia and other low-boiling point pure working fluids or mixed working fluids.

The cold energy transport bin can change the buoyancy of the cold energy transport bin through the volume change of the elastic oil bladder, thereby realizing the unpowered submergence of the cold energy transport bin underwater.

The insulation layer of the cold energy transport warehouse is a sandwich structure. From the inside to the outside, there are anti-corrosion, heat preservation and waterproof layers. It can be but is not limited to the following materials that can achieve the corresponding functions: outer layer of neoprene rubber, middle layer of polyvinyl chloride foam, Polyurethane inner layer.

A gas-liquid phase change material is stored inside the gas-liquid phase change cavity. The saturation temperature of the gas-liquid phase change material is 4-8°C. The gas-liquid phase change material is realized by exchanging heat with deep cold seawater in the cold seawater pipeline. When the variable material is condensed, the liquid gas-liquid phase change material can be released into the condenser through the magnetic interface (two), and the liquid gas-liquid phase change material interacts with the working fluid in the condenser. Heat exchange is performed to achieve evaporation of the gas-liquid phase change material, and the periodic evaporation-condensation process is carried out to realize the transport of cold energy from the sea bottom to the sea surface.

Gas-liquid phase change materials can be, but are not limited to, the following: organic working fluids such as R134a and R245fa, inorganic working fluids such as water and ammonia, or other mixed working fluids; the phase change pressure of the gas-liquid phase change material is determined by the balance pressure Determined by the filling pressure in the cavity.

The internal filling gas of the balanced pressure chamber can be dry air, nitrogen, helium, etc. whose density is not sensitive to temperature, but is not limited to the above gases.

There is a cold seawater inlet with a pressure-sensitive valve and a cold seawater outlet with a pressure-sensitive valve. When the cold energy transport bin drops to a certain depth (about 800m), under the action of seawater pressure, the pressure-sensitive valve opens and cold seawater enters the phase change The material cavity exchanges heat with the gas-liquid phase change material. The gas-liquid phase change material evaporates and expands in volume, pushing the upper piston with the rack to move, driving the gear to rotate, and the gear further drives the belt. The rack-mounted lower piston moves and compresses the oil storage bin. The oil stored in the oil storage bin enters the elastic oil bag through the communication port. The elastic oil bag expands in volume, and the cold energy transport bin increases in volume, increases buoyancy, and floats up. Bringing cold energy from the seafloor to the surface of the ocean.

Closed power generation thermodynamic cycle structure. The closed power generation thermodynamic cycle structure can, but is not limited to, adopt organic Rankine cycle, Kalina cycle and other power generation thermodynamic cycles suitable for low temperature difference and low evaporation temperature conditions.

Cold energy transport bins and multifunctional anchor structures can be arranged on the transport guide rails according to actual conditions. The cold energy transport bins float on the left track to complete cold energy transfer. After the process, dive on the right track. After the first cold energy transport warehouse completes the cold energy transfer, the latter cold energy transport warehouse will be connected to the energy transmission port of the power generation warehouse to alternately "float - work - dive - energy storage" The working process realizes shortening the time interval of the thermal cycle power generation process.

Through the above technical solutions, compared with the existing technology, the present invention has the following beneficial effects:

1. The present invention uses renewable ocean temperature difference energy as driving energy, and proposes an ocean temperature difference energy power generation device that can be deployed underwater, spontaneously produces electric energy and stores it in a battery, and provides electric energy to autonomous underwater cruisers without the need for Rely on long-distance power transmission on land or shore charging;

2. In view of the problem of high self-consumption in the way of transporting cold seawater through pipelines, the present invention proposes a non-power-driven submersible cold seawater transport warehouse, which can use gas-liquid phase change materials to transport warm seawater on the surface of the ocean and cold seawater in the deep layer. The volume changes in the periodic evaporation-condensation process between the two, and the volume changes are transmitted to the elastomer to realize the volume change of the cold seawater transport bin, further realizing the buoyancy change of the cold seawater transport bin, and achieving unpowered submersibility. .

3. In view of the problems of trajectory, communication and cold energy transfer in the practical application of cold energy transport equipment, the present invention proposes a multi-functional anchor structure and a main and auxiliary body docking structure, and uses the anchor structure as an unpowered submersible cooling system at the same time. The transport guide rails of the energy transport warehouse constrain the ascent route of the cold energy transport warehouse to ensure the reliability and safety of cold energy transport; at the same time, the proposed double magnetic interface docking structure can use the phase change process to pressurize Positive feedback drives the liquid phase change material into the cooling components in the closed power generation thermodynamic cycle structure, which minimizes the power consumption of the cold source pump and increases the net output power of the power generation device.

4. In view of the problems of strong intermittent and low time efficiency of the ocean thermoelectric power generation system caused by the long working cycle of the cold energy transport bin, the present invention proposes a problem-solving idea of "streamline cold energy transport". Several cold energy transport bins can be arranged on the transport guide rails. The cold energy transport bins float on the left track and dive on the right track after completing the cold energy transfer process. After the first cold energy transport warehouse completes the cold energy transfer, the next cold energy transport warehouse will be connected to the energy transmission port of the power generation warehouse, which is achieved through an alternating working process of "floating - working - diving - energy storage". The purpose is to shorten the time interval of the thermal cycle power generation process, thereby improving the time efficiency of the device's power generation.

Description of drawings

In order to explain the embodiments of the present invention or the technical solutions in the prior art more clearly, the drawings needed to be used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings in the following description are only These are some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on the structures shown in these drawings without exerting creative efforts. In the attached picture:

Figure 1 is a schematic diagram of the overall structure of the present invention;

Figure 2 is a schematic structural diagram of the unpowered latent cooling energy transport bin of the present invention;

Figure 3 is a schematic diagram of the gear drive structure in the cold energy transport warehouse of the present invention;

Figure 4 is a schematic diagram of the working mode of the assembly line cold energy transport of the present invention;

Figure 5 is a schematic diagram of the transport track in the multifunctional anchorage structure of the present invention;

Figure 6 is a schematic structural diagram of an organic Rankine cycle power generation bin according to an embodiment of the present invention;

Figure 7 is a schematic structural diagram of the Kalina cycle power generation bin according to the embodiment of the present invention;

Figure 8 is an organic Rankine cycle temperature entropy diagram according to an embodiment of the present invention;

Figure 9 is a Kalina cycle temperature entropy diagram according to an embodiment of the present invention;

Among them: 1-power generation warehouse; 101-pressure-resistant warehouse; 102-warm seawater inlet; 103-warm seawater outlet; 1041-magnetic suction interface; 1042-magnetic suction interface; 105-cold source pump; 106-cold source pipe; 107 -Condenser; 108-working fluid pipeline; 109-working fluid pump; 110-heat source pipeline; 111-evaporator; 112-turbine; 113-turbine main shaft; 114-generator; 115-battery; 116-magnetic suction Charging port; 117-cable; 118-separator; 119-regenerator; 120-throttle valve; 121-mixer; 2-heat source pump; 3-cold energy transport bin; 301-pressure-resistant shell; 3021 -Magnetic interface; 3022-Magnetic interface; 303-Cold source inlet with pressure-sensitive valve; 304-Cold source outlet with pressure-sensitive valve; 305-Insulation layer; 3051-Waterproof layer; 3052-Insulation layer; 3053-Anti-corrosion layer ; 306-cold seawater flow channel; 307-gas-liquid phase change chamber; 3081-piston with rack; 3082-piston with rack; 309-balance pressure chamber; 310-oil storage chamber; 311-connection port ; 312-Elastic oil bag; 313-Gear; 401-Anchor concrete block; 402-Mooring rope; 403-Transportation track; 4031-Mooring rope sleeve; 4032-Slide rail; 4033-Ball pulley; 4034- Connecting rod; 404-mooring buckle; 501-sea bed; 502-sea surface; 503-autonomous underwater cruiser; 6-working fluid saturation line/basic ammonia-water mixture saturation line; 7-working fluid workflow line; 8-Warm seawater energy release curve; 9-Gas-liquid phase change material release/storage curve; 10-Cold seawater energy release curve; 11-Ammonia-poor working fluid saturation line; 12-Ammonia-rich working fluid saturation line; S1-Evaporation S2 - the saturated gaseous point of the working fluid in the evaporator; S3 - the evaporator working fluid outlet status point; S4 - the condenser working fluid inlet status point; S5 - the condenser working fluid outlet status point; S6 - Working fluid pump working fluid outlet status point; S7 - evaporator warm seawater inlet status point; S8 - evaporator warm seawater outlet status point; S9 - condenser gas-liquid phase change material inlet status point; S10 - condenser gas-liquid phase change Material outlet status point; S11-cold seawater inlet status point; S12-cold seawater outlet status point; R1-evaporator working fluid outlet status point; R2-separator ammonia-rich working fluid outlet status point; R3-turbine ammonia-rich working fluid R4 - separator lean ammonia working medium outlet status point; R5 - throttle valve lean ammonia working medium inlet status point; R6 - throttle valve lean ammonia working medium outlet status point; R7 - mixer working medium outlet Status point; R8 - condenser working fluid outlet status point; R9 - working fluid pump outlet status point; R10 - evaporator working fluid inlet status point; R11 - evaporator warm seawater inlet status point; R12 - evaporator warm seawater outlet status point; R13-condenser gas-liquid phase change material inlet status point; R14-condenser gas-liquid phase change material outlet status point; R15-cold seawater outlet status point; R16-cold seawater inlet status point.

Detailed ways

In order to deepen the understanding of the present invention, the present invention will be further described in detail below with reference to the accompanying drawings. This embodiment is only used to explain the present invention and does not constitute a limitation on the protection scope of the present invention.

Figure 1 shows the overall structure of an energy storage type ocean temperature difference energy underwater conversion device, including a power generation warehouse 1 installed below sea level, a heat source pump 2, a cold energy transport warehouse 3 and a multi-functional anchorage structure. The power generation warehouse 1 is connected to the anchor concrete block 401 fixed on the seabed through a mooring rope 402 to play a positioning role. The heat source pump 2 is connected to the power generation warehouse 1 through the warm seawater inlet 103. The cold energy transport warehouse 3 is connected to the magnetic suction interface 104 of the power generation warehouse through two magnetic suction interfaces 302 during the sea surface cooling process. After the cold energy release is completed, , the magnetic suction interface 302 detaches, and sinks to the seabed along the mooring rope 402 to store cold again; driven by the temperature difference between the seawater on the ocean surface and the cold energy contained in the cold energy power generation bin, the power generation warehouse 1 realizes on-site capture and conversion of the ocean temperature difference energy. . The electric energy generated by the power generation cabin 1 is stored in the battery 115 and provides power supply to the autonomous underwater vehicle through the magnetic charging port 116 of the power generation cabin 1 .

Figure 2 shows the structure of the unpowered latent cooling energy transport bin. It includes a pressure-resistant shell 301, a magnetic interface 302, a pressure-sensitive valve 303, an insulation layer 305, a cold seawater flow channel 306, a gas-liquid phase change chamber 307, a piston with a rack 308, a balance pressure chamber 309, and an oil storage chamber. 310, communication port 311, elastic oil bag 312, gear 313. There is a low-boiling point gas-liquid phase change material on the left side of the upper piston 308 and nitrogen on the right side. Nitrogen is on the left side of the lower piston 308 and hydraulic oil is on the right side. The elastic oil bladder 312 is filled with low-density hydraulic oil. The pressure-resistant shell 301 is divided into three layers, namely a neoprene anti-corrosion layer 3051, a polyvinyl chloride foam insulation layer 3052 and a molded polyurethane waterproof protective layer 3053, to achieve the effect of "anti-corrosion-insulation-waterproof". A pressure-sensitive switch 303 is provided at the inlet and outlet of the seawater pipeline. When the surface pressure reaches the threshold, the pipeline is opened.

Figure 3 shows the principle of action of the gear 313 on the piston 308 in the unpowered latent cooling energy transport chamber 3. The gear 313 is connected to a rack at the front and rear respectively, and the racks are each relatively fixed to the piston 308 on one side. When the upper piston 308 moves, the piston 308 will drive the rack fixed to it to move. Due to the existence of the gear 313, the lower piston 308 and the rack connected thereto will move in opposite directions. In practical applications, the magnitude of the movement can be controlled by the size and number of the gear 313 and the rack.

Figure 4 shows the operating principle of the assembly line cold energy transport mechanism. The mooring structure is connected to the power generation warehouse through mooring buckles 404. The transport track 403 is divided into a left floating track, a right submerging track and a connecting track in the middle. There is a certain height difference between the top of the floating track and the top of the submersing track. Several cold energy transport bins 3 are arranged on the transport track 403. The cold energy transport bins 3 float on the left track. After completing the cold energy transfer process, they are released by the power generation bin 101 through the magnetic suction interface 1041 and the magnetic suction interface 1042. The repulsive force pushes the cold energy transport warehouse 3 to move to the right through the connecting track and enters the submersible track. After the first cold energy transport warehouse completes the cold energy transfer, the next cold energy transport warehouse will be connected to the energy transmission port of the power generation warehouse, which is achieved through an alternating working process of "floating - working - diving - energy storage". The purpose is to shorten the time interval of the thermal cycle power generation process, thereby improving the time efficiency of the device's power generation.

Figure 5 shows the specific structure of the transport track in the multifunctional anchorage structure. Including mooring rope sleeve 4031, slide rail 4032, ball pulley 4033 and connecting rod 4034. The mooring rope sleeve 4031 is fixed on the back of the slide rail 4032. The mooring rope 402 passes through the mooring rope sleeve 4031 and is fixed to the transport track 403. The cold energy transport warehouse 3 is connected to the spherical pulley 4033 through the connecting rod 4034. The spherical pulley 4033 It can move freely in the slide rail 4032 to realize the floating and descending movements of the cold energy transport warehouse 3.

Figure 6 shows the structure of the ocean thermoelectric organic Rankine cycle power generation chamber 1 in the embodiment. The power generation bin 1 takes the organic Rankine cycle as the basic configuration, uses single organic matter or mixed organic matter as the working fluid, and uses the temperature difference between the thermal energy carried by the surface warm seawater and the cold energy carried by the cold energy transport bin to generate electrical energy. Specifically, the power generation warehouse includes a pressure-resistant warehouse 101, a warm seawater inlet 102, a warm seawater outlet 103, a magnetic suction interface 104, a cold source pump 105, a cold source pipeline 106, a condenser 107, a working fluid pipeline 108, and a working fluid pump 109. Heat source pipe 110, evaporator 111, turbine 112, turbine spindle 113, generator 114, battery 115, magnetic charging port 116, cable 117; cold source pump 105, condenser 107, working medium pump 109, evaporator 111 , turbine 112, generator 114, battery 115, heat source pipeline 110, cold source pipeline 106, working fluid pipeline 108, cable 117 are packaged in the pressure chamber 101; condenser 107, working fluid pump 109, evaporator 111, The turbine 112 is connected through the working medium pipeline to form a closed turbine power generation thermodynamic cycle; the warm seawater inlet 102, the heat source pipeline 110, the evaporator 111 and the warm seawater outlet 102 are connected to form an energy release path for the thermal energy carried by the warm seawater; the magnetic interface 1041. The cold source pump 105, the condenser 107 and the magnetic interface 1042 form an energy release path for the cold energy carried in the cold energy transport bin 3; the turbine main shaft 113 is connected to the rotor of the generator 114; The generator 114, the battery 115 and the magnetic charging port 116 are connected through a cable 117.

Figure 7 shows the structure of the ocean temperature difference energy Kalina cycle power generation chamber 1 in the embodiment. The power generation bin 1 uses the Kalina cycle as the basic configuration, uses an ammonia-water mixture as the working fluid, and uses the temperature difference between the thermal energy carried by the surface warm seawater and the cold energy carried by the cold energy transport bin to generate electrical energy. Specifically, pressure chamber 101, warm seawater inlet 102, warm seawater outlet 103, magnetic interface 104, cold source pump 105, cold source pipeline 106, condenser 107, working fluid pipeline 108, working fluid pump 109, heat source pipeline 110 , evaporator 111, turbine 112, turbine spindle 113, generator 114, battery 115, magnetic charging port 116, cable 117, separator 118, regenerator 119, throttle valve 120, mixer 121; cold source Pump 105, condenser 107, working fluid pump 109, evaporator 111, turbine 112, generator 114, battery 115, heat source pipeline 110, cold source pipeline 106, working fluid pipeline 108, cable 117, separator 118, heat recovery The condenser 119, the throttle valve 120, and the mixer 121 are packaged in the pressure chamber 101; the condenser 107, the working fluid pump 109, the evaporator 111, the separator 118, the turbine 112, the mixer 121, the throttle valve 120, The regenerator 119 is connected through the working medium pipeline 108 to form a closed turbine power generation thermodynamic cycle; the warm seawater inlet 102, the heat source pipeline 110, the evaporator 111 and the warm seawater outlet 103 are connected to form an energy release path for the thermal energy carried by the warm seawater; magnetic The suction interface 104, the cold source pump 105, the condenser 107 and the magnetic suction interface 104 form an energy release path for the cold energy carried in the cold energy transport bin 3; the turbine main shaft is connected to the generator rotor; the The generator 114, the battery 115 and the magnetic charging port 116 are connected through a cable 117.

The specific working process of the above embodiment is as follows:

As shown in Figure 1, the energy storage type ocean temperature difference energy underwater conversion device directly extracts surface temperature seawater as a heat source, uses low boiling point phase change materials in the unpowered submersible cold energy transport chamber as a cold source, and uses surface temperature seawater and The temperature difference between the phase change materials drives the closed power generation thermodynamic cycle structure to generate electricity. Seawater temperature tends to decrease with increasing vertical depth. In the South China Sea, the temperature of surface seawater (0 to 50m below sea level) remains above 25°C all year round, and the temperature of deep seawater (below 600m) is below 7°C all year round.

The energy storage type ocean temperature difference energy underwater conversion device uses organic Rankine cycle or Kalina cycle to generate electricity. The specific process is as follows:

The structure of the power generation warehouse of the energy storage type ocean temperature difference energy underwater conversion device using organic Rankine cycle power generation is shown in Figure 4. After the surface warm seawater enters the heat source pipe 110 from the warm seawater inlet 102, it enters the evaporator 111 to exchange heat with the circulating working fluid, heats and evaporates the circulating working fluid into a gas phase, and is finally discharged into seawater through the warm seawater outlet 103. The circulating working fluid is evaporated into high-temperature and high-pressure gas in the evaporator 111 and then enters the turbine 112. It pushes the turbine impeller to do work and turns into low-temperature and low-pressure gas. Then it enters the condenser 107, exchanges heat with the low-temperature phase change material and becomes gas. It is a low-temperature and low-pressure liquid that is pressurized by the working fluid pump 110 and then enters the evaporator 111 again, thereby forming a power generation cycle.

The power generation warehouse structure of the energy storage type ocean thermoelectric energy underwater conversion device using Kalina cycle power generation is shown in Figure 5. After the surface warm seawater enters the heat source pipe 110 from the warm seawater inlet 102, it enters the evaporator 111 to exchange heat with the circulating working fluid ammonia-water mixture, heats and evaporates the circulating working fluid into a gas phase, and is finally discharged into seawater through the warm seawater outlet 103. . The heat-exchanged ammonia-water working fluid enters the separator 118 for separation. After separation, the working fluid becomes ammonia-rich steam and ammonia-poor working fluid. Ammonia-rich steam enters the turbine 112 to generate electricity, and the ammonia-poor working fluid enters the regenerator 119 to preheat the ammonia-water working fluid. After preheating, the ammonia-poor working fluid enters the throttle valve 120 for decompression, and interacts with the steam turbine. The spent steam is mixed in the mixer 121 and enters the condenser 107. After the ammonia-water mixture is condensed by the condenser 107, it enters the working medium pump 109 for pressure increase, and then enters the regenerator 119 for preheating, thus forming a power generation cycle.

The specific process of transporting cold energy in the unpowered submersible cold energy transport bin 3 of the energy storage type ocean temperature difference energy underwater conversion device is as follows:

The energy storage type ocean temperature difference energy underwater conversion device adopts a working mode that uses volume changes to cause buoyancy changes to achieve cold energy transport, as shown in Figure 2. The matching structure of the internal piston 308 and the gear 313 is shown in Figure 3. When the liquid phase change material exchanges heat with the circulating working fluid in the condenser 107 and expands into the gas phase, the volume becomes larger and the pressure increases. The upper piston 308 moves to the right under the action of air pressure, and the upper piston 308 drives the The racks move to the right together. Due to the existence of the gear 313, the lower piston 308 and the rack connected to it will move in the opposite direction. At this time, a negative pressure is formed in the lower right chamber, and the hydraulic pressure in the elastic oil bag 312 The oil will be attracted to flow into the chamber, and the elastic oil bladder 312 will shrink, and the buoyancy of the entire cold energy transport warehouse 3 will be reduced. After completing the energy release process, it will be released from the constraint, and will sink to the seabed along the transport guide rail to complete energy storage. When the cold energy transport bin 3 drops to a certain depth, the pressure of seawater on the seawater pipeline inside the cold energy transport bin 3 reaches a threshold, the seawater pipeline is opened, and seawater enters the cold seawater flow channel 306 to cool the cold storage phase change material. Similarly, after the cold storage process is completed, the elastic oil bladder 312 expands, and the cold energy transport warehouse 3 floats along the transport guide rail, thus forming a cycle.

The specific working process of the cold energy transport bin transferring cold energy to the condenser is as follows:

When the cold energy transport warehouse 3 floats up to the pressure-resistant warehouse 101 and is detected by the infrared sensing system, the control system of the pressure-resistant warehouse 101 starts to function, activates the electromagnetic relay and magnetically fixes the cold energy transport warehouse 3, which is completed using a specific mechanical structure. The energy transmission port 302 is connected to the energy transmission pipeline, and the cold source pump 105 starts to work, sucking in the liquid phase change material in the gas-liquid phase change chamber 307 through the lower energy transmission port, and the phase change material enters the condenser and moves it into the condenser. The remaining gas phase change material is pressed into the gas-liquid phase change chamber 307 from the upper energy transfer port. At the same time, the liquid phase change material entering the condenser is heated and evaporates into gas, which further pressurizes the inside of the condenser 107 and presses the gas phase change material from the upper energy transfer port into the gas-liquid phase change chamber 307, causing positive feedback. Pushing the phase change material into the condenser 107 greatly reduces the power consumption of the cold source pump 105 to complete the cold energy transfer process. When the cold energy transfer process is completed, the phase change material in the cold energy transport bin 3 is completely evaporated, the overall pressure of the "condenser-cold energy transport bin" system increases, and a small part of the gas phase change material remains in the condenser 107 , most of the gas phase change material returns to the cold energy transport bin 3 to complete the next energy storage process, thus forming a cycle.

Taking the South China Sea as an example, as shown in Figure 1, the power generation warehouse 101 of the energy storage type ocean temperature difference energy underwater conversion device is suspended in the surface seawater under the action of the mooring rope 402 and the anchor concrete block 401. The surface warm seawater is extracted through the heat source pump 102, and the cold energy of the deep cold seawater is stored through the cold energy transport bin 3. The warm seawater extracted by the heat source pump 102 enters the evaporator 111. The temperature of the imported warm seawater is 28°C, the temperature of the cold seawater is 4°C, and the phase change temperature of the phase change material used in the cold energy transport warehouse 3 is 6°C. Set at The heat exchange temperature difference of the cold energy transport bin 3 is 1°C. During the transportation process, the phase change material has a temperature rise of 1°C, and the phase change material entering the condenser 111 is 6°C.

This embodiment will use the organic Rankine cycle and the Kalina cycle as alternatives for the closed power generation thermodynamic cycle structure to illustrate the thermodynamic cycle process.

The organic Rankine cycle is used as the design scheme of the closed thermodynamic cycle structure for power generation. The examples of the thermodynamic cycle process are as follows:

According to the actual working conditions, this example uses R134a as the circulating working fluid in the power generation thermodynamic cycle of the energy storage type ocean thermodifferential energy underwater conversion device. The circulating working fluid can be but is not limited to R134a. The circulating working fluid R134a exchanges heat with the surface warm seawater at 28°C in the evaporator 111. The warm seawater releases heat, and the temperature drops to 24°C. R134a is heated to become superheated gas; the heated and evaporated gaseous working fluid R134a drives the turbine 112 at high speed Rotates and drives the generator 114 to generate electric energy; the outlet exhaust gas exchanges heat with the 6°C cooling phase change medium R245fa in the condenser 107 (the designed pressure inside the cold energy transport bin is 0.069MPa), and the cooling phase change medium R245fa Phase change occurs when absorbing heat. During the phase change, the temperature remains unchanged, and R134a condenses into a saturated liquid state; the working fluid pump 109 drives the liquid R134a into the evaporator 111 where it is heated and undergoes phase change and expands into a gas, completing a working fluid cycle. The working fluid cycle temperature entropy diagram is shown in Figure 6. The pinch temperature differences ΔT _PP1 and ΔT _PP2 of the evaporator 111 and the condenser 107 are 2°C and 5°C respectively (to ensure that the cooling phase change medium can undergo phase change). When other irreversible losses in the system other than those caused by heat exchange are not taken into account, the thermodynamic parameters of each state point in the cycle on the temperature entropy diagram are obtained through the state parameters of the R134a working fluid, as shown in Table 1.

Table 1: Thermodynamic parameters of each state point of the cycle on the thermoentropy diagram of the organic Rankine cycle

According to the thermodynamic parameters in Table 1, it can be seen that the heat absorbed by unit mass of working fluid R134a in the evaporator 111 is ΔQ _e =198.15kJ/kg, the ideal enthalpy drop of the turbine inlet and outlet is ΔH ₁ =8.48kJ/kg, and the heat released by the condenser 107 is ΔQ _c =189.93kJ/kg, set the generator 114 output power P _w =1kW, turbine efficiency eta _w =85%, mechanical efficiency eta _m =98%, generator efficiency eta _p =93%, so the required circulating working fluid The mass flow rate of R134a is 0.15kg/s. It is further obtained that the heat absorbed during the evaporation process in the evaporator is 30.16kW, and the heat released during the condensation process is 28.91kW. During the design process, the temperature difference ΔT between the inlet and outlet of the warm seawater in the evaporator is 4°C. According to the calculation, the mass flow rate of warm seawater required by the evaporator 111 is 1.70kg/s.

In this example, R245fa is used as the cold storage medium of the cold energy transport bin 3. The design pressure is 0.069MPa, and its phase change temperature is 6°C. At this time, its phase change latent heat is 201.18kJ/kg. The cooler is designed to carry 50kg of cold storage medium in a single cycle, so the first stage of a single power generation can last approximately 347.94s, and a total of 347.94kJ of electricity can be generated.

In order to obtain the net output electric power of the energy storage type ocean thermoelectric energy underwater conversion device, it is necessary to deduct the system self-consumption, including the power consumption of the working medium pump 109, the heat source pump 2, the cold source pump 105 and the control system. The working fluid pump 109 is mainly used to transport the working fluid and increase the working fluid pressure head. According to Table 1, it can be seen that the total energy obtained by the unit working fluid through the working fluid pump 109 is ΔH _p = 0.26kJ/kg. Suppose the efficiency of the working fluid pump 111 is η _p = 0.75, the total power consumption of the working medium pump W _p =0.0528kW is obtained. The power consumption of heat source pump 2 is based on Calculation, where Q _v is the volume flow rate of the conveyed fluid, ΔP is the total resistance, eta is the efficiency of the pump, eta = 0.8, and the flow resistance P _hex on the seawater side of the evaporator 111 is taken to be 1kPa. The length of the warm seawater pipeline l _w =20m, select the inner diameter of the warm seawater pipeline D ₁ =0.1m, and the resistance along the way is Local resistance loss based on/> Calculation shows that the local resistance loss is P _w2 =231Pa, and the total resistance that the seawater pump 102 needs to overcome is P _wp =P _w1 +P _w2 +P _hex =

1243Pa, the power consumption W _wp is 0.024kW; therefore, the self-consumption of the closed power generation thermodynamic cycle system designed in the embodiment is W _pu =W _wp + W _p =0.0768kW, and the power output to the battery 115 is 0.9232kW. The power consumption of the control system in a single cycle is set to 10kJ, and the total power consumption of the cold source pump 105 used to pump in the phase change cold storage medium R245fa in a single cycle is 1kJ. Therefore, the total power consumption in the power generation stage is 37.72kJ, and the total net power is 310.22kJ.

The Kalina cycle is used as the design scheme of the closed thermodynamic cycle structure for power generation. The examples of the thermodynamic cycle process are as follows:

According to the actual working conditions, this example uses an ammonia-water mixture with a mass concentration of 95% as the circulating working fluid in the power generation thermodynamic cycle of the energy storage type ocean thermoelectric energy underwater conversion device. The ammonia-water mixture evaporates by exchanging heat with the surface warm seawater at 28°C in the evaporator 111. The warm seawater releases heat and the temperature drops to 24°C. The ammonia-water mixture is heated to a gas-liquid mixture of 26°C with a pressure of 0.9MPa; The heated and evaporated gaseous ammonia-water mixture enters the separator 118 and is separated into ammonia-rich vapor and ammonia-lean solution. The ammonia-rich vapor drives the turbine 112 to rotate at high speed to drive the generator 114 to generate electricity, while the lean ammonia solution enters the regenerator 119 to preheat the ammonia-water mixture that is about to enter the evaporator 111. The low-temperature and low-pressure ammonia-rich vapor at the outlet of the turbine 112 is mixed with the lean ammonia solution cooled by the regenerator 119 and throttled by the throttle valve 120 in the mixer 121. The mixed ammonia-water mixture is condensed in the condenser 107. The cold energy carried in the cold energy transport bin 3 is cooled, and the cooled pure liquid ammonia-water mixture is boosted by the working medium pump 109 and heated by the regenerator 119, and then enters the evaporator 111 again to absorb heat and evaporate. This forms a cycle. The working fluid cycle temperature entropy diagram is shown in Figure 7. The pinch temperature differences ΔT _PP1 and ΔT _PP2 of the evaporator 111 and the condenser 107 are 2°C and 5°C respectively (to ensure that the cooling phase change medium can undergo phase change). Excluding other irreversible losses in the system except those caused by heat exchange, the thermodynamic parameters of each state point of the cycle on the temperature entropy diagram are obtained through the ammonia-water working fluid state parameters, as shown in Table 2.

Table 2: Thermodynamic parameters of each state point of the cycle on the Kalina cycle thermoentropy diagram

According to the thermodynamic parameters in Table 2, it can be seen that the heat absorbed by the unit mass of the working fluid ammonia-water mixture in the evaporator 111 is ΔQ _e =767.22kJ/kg, the ideal enthalpy drop of the turbine inlet and outlet ΔH ₁ =37.72kJ/kg, and the condenser 107 discharges The heat ΔQ _c =744.46kJ/kg, the output power P _w of the generator 114 is set =1kW, the turbine efficiency eta _w =85%, the mechanical efficiency eta _m =98%, and the generator efficiency eta _p =93%, so it is required The mass flow rate of the circulating working fluid ammonia-water mixture is 0.034kg/s. It is further obtained that the heat absorbed during the evaporation process in the evaporator is 26.255kW, and the heat released during the condensation process is 25.312kW. During the design process, the temperature difference ΔT between the inlet and outlet of the warm seawater in the evaporator is 4°C. According to the calculation, the mass flow rate of warm seawater required by the evaporator 111 is 1.60kg/s.

In this example, R245fa is used as the cold storage medium of the cold energy transport bin 3. The design pressure is 0.069MPa, and its phase change temperature is 6°C. At this time, its phase change latent heat is 201.18kJ/kg. The cooler is designed to carry 50kg of cold storage medium in a single cycle, so the first stage of a single power generation can last approximately 397.40s, and a total of 397.40kJ of electricity can be generated.

In order to obtain the net output electric power of the energy storage type ocean thermoelectric energy underwater conversion device, it is necessary to deduct the system self-consumption, including the power consumption of the working medium pump 109, the heat source pump 2, the cold source pump 105 and the control system. The working fluid pump 109 is mainly used to transport the working fluid and increase the working fluid pressure head. According to Table 1, it can be seen that the total energy obtained by the unit working fluid through the working fluid pump 109 is ΔH _p = 0.46kJ/kg. Suppose the efficiency of the working fluid pump 111 is η _p = 0.75, the total power consumption of the working medium pump W _p =0.0209kW is obtained. The power consumption of heat source pump 2 is based on Calculation, where Q _v is the volume flow rate of the conveyed fluid, ΔP is the total resistance, eta is the efficiency of the pump, eta = 0.8, and the flow resistance P _hex on the seawater side of the evaporator 111 is taken to be 1kPa. The length of the warm seawater pipeline l _w =20m, select the inner diameter of the warm seawater pipeline D ₁ =0.1m, and the resistance along the way is Local resistance loss based on/> Calculation shows that the local resistance loss is P _w2 =203.28Pa, the total resistance that the seawater pump 102 needs to overcome is P _wp =P _w1 +P _w2 +P _hex =1213.84Pa, and the power consumption W _wp is 0.022kW; therefore, the design in the embodiment The self-consumption of the closed power generation thermodynamic cycle system is W _pu =W _wp +W _p =0.0429kW, and the power output to the battery 115 is 0.9571kW. The power consumption of the control system in a single cycle is set to 10kJ, and the total power consumption of the cold source pump 105 used to pump in the phase change cold storage medium R245fa in a single cycle is 1kJ. Therefore, the total power consumption in the power generation stage is 28.05kJ, and the total net power is 369.35kJ.

The embodiments of the present invention show the specific design technical parameters of the closed power generation thermodynamic cycle in the power generation bin 1 of the energy storage type ocean temperature difference energy underwater conversion device. The design technical parameters can be but are not limited to the embodiments, and more optimal ones can be selected during the design process. Low boiling point organic working fluid with high performance, forming a more efficient power generation cycle.

The present invention aims to provide an energy storage type ocean temperature difference energy underwater conversion device with an unpowered submersible cold energy transport warehouse as the core, which is suitable for energy supply of autonomous underwater vehicles and can generate electrical energy autonomously, reliably and stably. ; Through ocean temperature difference energy power generation and automatic control technology, the charge and discharge of the storage module is controlled and the independent connection and cooperation of the cold energy transport warehouse; through the application of the variable volume cold energy transport warehouse and its ancillary technologies, the cold sea water is avoided. The large power consumption caused by long-distance transportation has greatly improved the feasibility of ocean temperature difference energy generation.

The above-mentioned specific embodiments are only to illustrate the technical concepts and structural features of the present invention, and are intended to enable relevant persons familiar with this technology to implement them. However, the above content does not limit the scope of protection of the present invention. Any equivalent changes or modifications made in essence shall fall within the protection scope of the present invention.

Claims (10)

1. An energy storage type ocean temperature difference energy underwater conversion device, which is characterized in that it includes: Heat source pump, used to provide ocean surface temperature seawater; The cold energy transport warehouse is used to provide deep cold seawater in the ocean; the cold energy transport warehouse includes a gas-liquid phase change chamber, an oil storage chamber and an elastic oil bag, and the oil storage chamber is connected with the elastic oil bag; the gas The liquid phase change chamber includes a phase change material chamber and a first balance chamber, and the oil storage chamber includes an oil chamber and a second balance chamber; a linkage mechanism is provided between the gas-liquid phase change chamber and the oil storage chamber. When the volume of the phase change material in the phase change material cavity increases or decreases due to the evaporation-condensation process of the phase change material cavity, the linkage mechanism causes the volume of the oil cavity to increase or decrease simultaneously; when the volume of the oil cavity increases, When the elastic oil bladder shrinks, the buoyancy of the cold energy transport bin decreases and dives; when the volume of the oil chamber shrinks, the elastic oil bladder increases, and the buoyancy of the cold energy transport bin increases and rises; A power generation warehouse that uses the temperature difference between the warm seawater on the ocean surface provided by the heat source pump and the cold seawater in the deep ocean provided by the cold energy transport warehouse to generate electricity and store it; as well as A multifunctional anchoring structure anchors the power generation warehouse to the seabed and provides an operating track for the cold energy transport warehouse. 2. The energy storage type ocean temperature difference energy underwater conversion device according to claim 1, characterized in that the multifunctional anchorage structure includes a mooring rope, an anchorage concrete block and a transportation guide rail; the anchorage concrete The block is fixed on the seabed and is connected to the power generation warehouse through the mooring rope to play a positioning role; the mooring rope is relatively fixed to the transportation guide rail to provide a fixed running trajectory for the cold energy transportation warehouse. Constrain the ascent route of the cold energy transport bin. 3. The energy storage type ocean temperature difference energy underwater conversion device according to claim 2, characterized in that a plurality of the cold energy transport bins are arranged on the transport guide rail, and a plurality of the cold energy transport bins alternate work, shortening the time interval between the previous and subsequent power generation processes. 4. The energy storage type ocean temperature difference energy underwater conversion device according to claim 3, characterized in that the transport track is divided into a left floating track, a right submerging track and a connecting track in the middle. The top of the floating track is There is a height difference from the top of the submersible track; the cold energy transport cabin floats up along the left floating track, and at the highest point slides along the connecting track to the submerge track and dives due to the height difference. 5. The energy storage type ocean temperature difference energy underwater conversion device according to claim 1, characterized in that the linkage mechanism includes an upper piston, a lower piston and a gear, and an upper piston and a lower piston are respectively provided with an The gear meshing rack; both sides of the upper piston are respectively the phase change material chamber and the first balance pressure chamber; both sides of the lower piston are respectively the oil chamber and the second balance pressure chamber; The position of the phase change material chamber on the upper piston is opposite to the position of the oil chamber on the lower piston. 6. The energy storage type ocean temperature difference energy underwater conversion device according to claim 1, characterized in that the power generation bin uses a turbine power generation thermodynamic cycle as a basic configuration to realize thermal work-thermoelectricity conversion of ocean temperature difference energy. 7. The energy storage type ocean temperature difference energy underwater conversion device according to claim 1, characterized in that the cold energy transport warehouse is configured with two upper and lower magnetic suction interfaces to achieve connection with the main and auxiliary bodies of the power generation warehouse. docking; and, the liquid phase change material entering the component that needs cooling in the power generation cabin is heated and evaporates into gas, further pressurizing the interior of the component that needs cooling, and pressing the gas phase change material into the air from the upper magnetic interface. In the liquid phase change chamber, positive feedback drives the phase change material into the components that require cooling, and uses the phase change process to supercharge the positive feedback to push the liquid phase change material into the components that require cooling in the power generation thermodynamic cycle structure, minimizing the need for cold source pumps. Consumes power. 8. The energy storage type ocean temperature difference energy underwater conversion device according to claim 1, characterized in that the power generation warehouse includes a pressure-resistant warehouse, a cold source pump, a closed power generation thermodynamic cycle structure, a battery, a heat source pipeline, and a cold source. Pipes, working fluid pipes, cables, magnetic charging ports, first magnetic interface and second magnetic interface; the warm seawater inlet of the power generation bin is connected to the heat source pump; the cold source pump, the cold source The pump, the battery, the heat source pipe, the cold source pipe, the working medium pipe, the cable and the closed power generation thermodynamic cycle structure are packaged in the pressure chamber; the heat source pipe and The heat-demanding components in the closed power generation thermodynamic cycle structure are connected to form an energy release path for the thermal energy carried by warm seawater; the first magnetic suction interface, the cold source pump, the second magnetic suction interface and the The components that require cooling in the closed power generation and thermodynamic cycle structure are connected to form an energy release path for the cold energy carried in the cold energy transport bin; the battery and the magnetic charging port are in the closed power generation and thermodynamic cycle structure. The power generation components are connected through cables; the magnetic charging port provides power supply for the autonomous underwater vehicle. 9. The energy storage type ocean temperature difference energy underwater conversion device according to claim 8, characterized in that the bottom of the pressure-resistant warehouse has a conformable groove for placing the cold energy transport warehouse, and the first magnetic The suction interface and the second magnetic suction interface are arranged at the conformable groove; infrared detection equipment is arranged around the first magnetic suction interface and the second magnetic suction interface. When the infrared detection equipment detects that the cold energy transport warehouse is in place After that, the first magnetic suction interface and the second magnetic suction interface are energized to produce magnetism through signal feedback, so that the first magnetic suction interface and the second magnetic suction interface are connected to the cold energy transport bin, so that the cold energy transport bin is connected to the cold energy transport bin. The energy transport warehouse, the cold source pump, and the cooling-requiring components in the closed power generation thermodynamic cycle structure are connected through the cold source pipeline to form a closed cold energy release path. 10. The energy storage type ocean temperature difference energy underwater conversion device according to claim 8, characterized in that the working fluid used in the closed loop of the closed power generation thermodynamic cycle structure is a low boiling point pure working fluid or a mixed working fluid. ; The low-boiling point pure working fluid is R245fa, R134a, R1233zd(E) or ammonia water; the low-boiling point mixed working fluid is a mixture of any two or more of R245fa, R134a, R1233zd(E) or ammonia water; the gas-liquid The gas-liquid phase change material is stored inside the phase change cavity. The saturation temperature of the gas-liquid phase change material is 4 ~ 8°C. The gas-liquid phase change material is realized by exchanging heat with deep cold seawater in the cold seawater pipeline. Condensation, releasing the liquid gas-liquid phase change material into the components that need cooling in the closed power generation thermodynamic cycle structure through the first magnetic suction interface, the second magnetic suction interface and the cold source pump, the The liquid gas-liquid phase change material exchanges heat with the working medium in the cooling component in the closed power generation thermodynamic cycle structure to realize the evaporation of the gas-liquid phase change material, and the periodicity of the evaporation-condensation process is realized. Transport of cold energy from the seabed to the sea surface; the gas-liquid phase change material is an organic working fluid, an inorganic working fluid or a mixed working fluid, the organic working fluid is R134a or R245fa, and the inorganic working fluid is water or ammonia; the gas-liquid phase change material is The phase change pressure of the phase change material is determined by the filling pressure in the balance pressure chamber; the filling gas inside the balance pressure chamber is dry air whose density is insensitive to temperature, and the dry air is nitrogen or helium; the insulation layer is a sandwich The structure, from the inside to the outside, is an anti-corrosion layer, an insulation layer and a waterproof layer; the waterproof layer material is neoprene, the insulation layer material is polyvinyl chloride foam, and the anti-corrosion layer material is polyurethane.