阅读说明：本技术 一种无负压的液氧大过冷度获取系统 (Large liquid oxygen supercooling degree acquisition system without negative pressure ) 是由 王磊 上官石 刘柏文 厉彦忠 马原 谢福寿 于 2020-04-22 设计创作，主要内容包括：一种无负压的液氧大过冷度获取系统,包括液氧储罐,液氧储罐的顶部增压口通过阀门和高压氦气瓶出口连接；液氧储罐底部出口通过循环泵连接氧-氦换热器的液氧侧入口,氧-氦换热器的液氧侧出口连接液氧储罐顶部回流口；氧-氦换热器的氦气侧出口通过冷氦压缩机连接液氮浴式换热器的氦气侧入口,液氮浴式换热器的氦气侧出口连接通过氦膨胀机连接氧-氦换热器氦气侧入口；液氮浴式换热器的液氮入口通过液位调节阀与液氮储罐底部出口连接,液氮浴式换热器的氮气出口经氮气泄流阀排空；本发明利用液氮预冷与冷氦压缩机制冷相结合,从而可不借助抽真空设备与负压换热装置,实现温度低于64K大过冷度液氧的发射场现场制备。(A non-negative pressure liquid oxygen high supercooling degree acquisition system comprises a liquid oxygen storage tank, wherein a top pressurizing port of the liquid oxygen storage tank is connected with an outlet of a high-pressure helium bottle through a valve; an outlet at the bottom of the liquid oxygen storage tank is connected with a liquid oxygen side inlet of the oxygen-helium heat exchanger through a circulating pump, and a liquid oxygen side outlet of the oxygen-helium heat exchanger is connected with a top return port of the liquid oxygen storage tank; a helium side outlet of the oxygen-helium heat exchanger is connected with a helium side inlet of the liquid nitrogen bath type heat exchanger through a cold helium compressor, and a helium side outlet of the liquid nitrogen bath type heat exchanger is connected with a helium side inlet of the oxygen-helium heat exchanger through a helium expander; a liquid nitrogen inlet of the liquid nitrogen bath type heat exchanger is connected with an outlet at the bottom of the liquid nitrogen storage tank through a liquid level regulating valve, and a nitrogen outlet of the liquid nitrogen bath type heat exchanger is emptied through a nitrogen gas leakage valve; the invention combines liquid nitrogen precooling and cold helium compressor refrigeration, thereby realizing the field preparation of the transmitting field of the supercooled liquid oxygen with the temperature lower than 64K without vacuum-pumping equipment and a negative pressure heat exchange device.)

1. The utility model provides a big supercooling degree of liquid oxygen acquisition system of no negative pressure, includes liquid oxygen storage tank (1), its characterized in that: a top pressurizing port of the liquid oxygen storage tank (1) is connected with an outlet of the high-pressure helium bottle (6) through a back pressure regulating valve (8) and a pressure release valve (7); an outlet at the bottom of the liquid oxygen storage tank (1) is connected with an inlet of the liquid oxygen leakage valve (2), an outlet of the liquid oxygen leakage valve (2) is connected with an inlet of a circulating pump (3), an outlet of the circulating pump (3) is connected with a liquid oxygen side inlet of the oxygen-helium heat exchanger (4), a liquid oxygen side outlet of the oxygen-helium heat exchanger (4) is connected with an inlet of a backflow check valve (5), and an outlet of the backflow check valve (5) is connected with a top backflow port of the liquid oxygen storage tank (1);

a helium side outlet of the oxygen-helium heat exchanger (4) is connected with an inlet of a cold helium compressor (13), an outlet of the cold helium compressor (13) is connected with a helium side inlet of a liquid nitrogen bath type heat exchanger (11), a helium side outlet of the liquid nitrogen bath type heat exchanger (11) is connected with an inlet of a helium expander (14), and an outlet of the helium expander (14) is connected with a helium side inlet of the oxygen-helium heat exchanger (4);

a liquid nitrogen inlet of the liquid nitrogen bath type heat exchanger (11) is connected with an outlet at the bottom of the liquid nitrogen storage tank (9) through a first liquid level regulating valve (10), and a nitrogen outlet of the liquid nitrogen bath type heat exchanger (11) is emptied through a first nitrogen gas leakage valve (12).

2. The system for obtaining the liquid oxygen supercooling degree without the negative pressure as claimed in claim 1, wherein: a recooling device (15) is additionally arranged, a first helium inlet of the recooling device (15) is connected with a helium side outlet of the oxygen-helium heat exchanger (4), a first helium outlet of the recooling device (15) is connected with an inlet of a cold helium compressor (13), an outlet of the cold helium compressor (13) is connected with a helium side inlet of a liquid nitrogen bath type heat exchanger (11), a helium side outlet of the liquid nitrogen bath type heat exchanger (11) is connected with a second helium inlet of the recooling device (15), a second helium outlet of the recooling device (15) is connected with an inlet of a helium expander (14), and an outlet of the helium expander (14) is connected with a helium side inlet of the oxygen-helium heat exchanger (4).

3. The system for obtaining the liquid oxygen supercooling degree without the negative pressure as claimed in claim 1, wherein: introducing a liquid nitrogen bath type subcooler (17), wherein a liquid oxygen inlet of the liquid nitrogen bath type subcooler (17) is connected with an outlet of a circulating pump (3), a liquid oxygen outlet of the liquid nitrogen bath type subcooler (17) is connected with an inlet of a backflow check valve (5) through a second stop valve (19), an inlet of the backflow check valve (5) is connected with an outlet of a first stop valve (18), an inlet of the first stop valve (18) is connected with a liquid oxygen side outlet of an oxygen-helium heat exchanger (4), and a liquid oxygen side inlet of the oxygen-helium heat exchanger (4) is connected with an outlet of the circulating pump (3) through a bypass valve (16); a liquid nitrogen inlet of the liquid nitrogen bath type subcooler (17) is connected with an outlet of the liquid nitrogen storage tank (9) through a second liquid level regulating valve (20), and a nitrogen outlet of the liquid nitrogen bath type subcooler (17) is emptied through a second nitrogen gas discharge valve (21).

4. The utility model provides a big supercooling degree of liquid oxygen acquisition system of no negative pressure adopts liquid oxygen filling process to realize that big supercooling degree obtains which characterized in that: the device comprises a liquid oxygen storage tank (1), wherein a bottom pressurization outlet of the liquid oxygen storage tank (1) is connected with an inlet of a pressurization and leakage valve (22), an outlet of the pressurization and leakage valve (22) is connected with an inlet of an air bath type vaporizer (23), an outlet of the air bath type vaporizer (23) is connected with a top pressurization port of the liquid oxygen storage tank (1) through a pressurization check valve (24), the bottom of the liquid oxygen storage tank (1) is higher than the top of the air bath type vaporizer (23), and liquid supply is realized by means of gravity;

an outlet at the bottom of the liquid oxygen storage tank (1) is connected with an inlet of a liquid oxygen leakage valve (2), an outlet of the liquid oxygen leakage valve (2) is connected with a liquid oxygen side inlet of the oxygen-helium heat exchanger (4), a liquid oxygen side outlet of the oxygen-helium heat exchanger (4) is connected with an inlet of a filling valve (25), an outlet of the filling valve (25) is connected with a filling port at the bottom of the rocket-mounted storage tank (26), and a pressurizing port at the top of the rocket-mounted storage tank (26) is connected with a high-pressure helium bottle (6) through a back pressure regulating valve (8) and a pressure release valve (7);

a helium side outlet of the oxygen-helium heat exchanger (4) is connected with an inlet of a cold helium compressor (13), an outlet of the cold helium compressor (13) is connected with a helium side inlet of a liquid nitrogen bath type heat exchanger (11), a helium side outlet of the liquid nitrogen bath type heat exchanger (11) is connected with an inlet of a helium expander (14), and an outlet of the helium expander (14) is connected with a helium side inlet of the oxygen-helium heat exchanger (4); a liquid nitrogen inlet of the liquid nitrogen bath type heat exchanger (11) is connected with an outlet at the bottom of the liquid nitrogen storage tank (9) through a first liquid level regulating valve (10), and a nitrogen outlet of the liquid nitrogen bath type heat exchanger (11) is emptied through a first nitrogen gas drainage valve (12).

5. The system for obtaining the liquid oxygen supercooling degree without the negative pressure as claimed in claim 4, wherein: a saturated nitrogen bath type subcooler (28) is added in front of the oxygen-helium heat exchanger (4), a liquid oxygen side inlet of the saturated nitrogen bath type subcooler (28) is connected with an outlet of the liquid oxygen leakage valve (2), a liquid oxygen side outlet of the saturated nitrogen bath type subcooler (28) is connected with a liquid oxygen side inlet of the oxygen-helium heat exchanger (4), a liquid oxygen side outlet of the oxygen-helium heat exchanger (4) is connected with an inlet of the filling valve (25), a liquid nitrogen side inlet of the saturated nitrogen bath type subcooler (28) is connected with a bottom outlet of the liquid nitrogen storage tank (9) through a liquid nitrogen control valve (27), and a nitrogen outlet of the saturated nitrogen bath type subcooler (28) is evacuated through a third nitrogen leakage valve (29).

6. The system for obtaining the liquid oxygen supercooling degree without the negative pressure as claimed in claim 1 or 4, wherein: the liquid oxygen storage tank (1) is arranged vertically or horizontally, is made of stainless steel, adopts vacuum powder heat insulation or vacuum multilayer heat insulation, and has the pressure bearing higher than 1 MPa.

7. The system for obtaining the liquid oxygen supercooling degree without the negative pressure as claimed in claim 1, wherein: the circulating pump (3) is immersed and cooled to ensure that the pump body is at the liquid oxygen temperature, and the pressurizing pressure head of the pump is larger than the liquid oxygen circulating flow pressure drop and the gravity pressure drop when the liquid oxygen storage tank (1) is at the lowest liquid level; the circulating pump (3) or adopts a submerged pump structure, and at the moment, the circulating pump (3) is arranged in the liquid oxygen storage tank (1) and is positioned in front of the liquid oxygen leakage valve (2).

8. The system for obtaining the liquid oxygen supercooling degree without the negative pressure as claimed in claim 1 or 4, wherein: the oxygen-helium heat exchanger (4) adopts a shell-tube type, plate type and plate-fin type dividing wall type heat exchanger structure, and a helium side flow channel is provided with a heat exchange strengthening structure with fins; the exterior of the heat exchanger is filled with pearly-lustre sand for heat insulation.

9. The system for obtaining the liquid oxygen supercooling degree without the negative pressure as claimed in claim 1 or 4, wherein: the cold helium compressor (13) is of a centrifugal structure, the inlet pressure is greater than 0.1MPa, and the pressure ratio is not less than 3.

10. The system for obtaining the liquid oxygen supercooling degree without the negative pressure as claimed in claim 1 or 4, wherein: the helium expander (14) adopts a centrifugal type, axial flow type or piston type structure, and the pressure after expansion is more than 0.1 MPa.

Technical Field

The invention relates to the technical field of acquisition of supercooling degrees of low-temperature propellants in space launching fields, in particular to a non-negative-pressure liquid oxygen large supercooling degree acquisition system.

Background

The low-temperature propellant comprises liquid oxygen/liquid hydrogen, liquid oxygen/liquid methane and liquid oxygen/kerosene combination, has the performance advantages of high specific impulse, high thrust, no toxicity, no pollution and the like, and can be widely applied to future aerospace emission. No matter which combination of low-temperature propellants is adopted, liquid oxygen is used as an oxidizer, so that the liquid oxygen characteristic has important influence on the overall performance of the rocket.

The oxygen injected into the low-temperature rocket is usually in a saturated state at normal pressure, the temperature is about 90K, and the density is about 1142kg/m³. If the liquid oxygen is supercooled, the liquid oxygen density is increased, and the carrying capacity of the rocket is improved. When the liquid oxygen is supercooled to 78K (liquid nitrogen saturation temperature under normal pressure), the density of the liquid oxygen is 1200kg/m³(ii) a When subcooled to 64K (nitrogen triple point temperature), the liquid oxygen density was 1264kg/m³(ii) a When subcooled to 55K (triple point temperature of oxygen), the liquid oxygen density was 1304kg/m³. Compared with saturated liquid oxygen, the density increasing rates at three supercooling degrees are respectively 5.1%, 10.7% and 14.2%. In addition, the rocket is filled with subcooled liquid oxygen, so that the difficult problem of gas-liquid two-phase flow management is avoided, the evaporation loss of the liquid oxygen is reduced, and the lossless storage time of the liquid oxygen space is prolonged.

The saturation temperature of oxygen at normal pressure is about 90K, the triple point temperature of oxygen is 54.4K, and the triple point pressure is 0.152 kPa; the saturation temperature of nitrogen at normal pressure is about 78K, the triple point temperature of nitrogen is about 63.2K, and the triple point pressure is about 12.54 kPa.

When liquid nitrogen supercooled liquid oxygen is adopted, supercooled liquid oxygen with the temperature higher than 78K can be prepared by normal-pressure heat exchange; vacuumizing the liquid nitrogen, and preparing the supercooled liquid oxygen of more than 63.2K by negative pressure liquid nitrogen/liquid oxygen heat exchange; if the supercooling degree of the liquid oxygen is further increased, the liquid nitrogen/liquid oxygen heat exchange system cannot meet the requirement.

The supercooled liquid oxygen can also be obtained by vacuumizing the liquid oxygen container, and the scheme can prepare the supercooled liquid oxygen with the temperature close to the three-phase point (54K). However, this method has significant disadvantages: an evacuation system with extremely high power consumption and complicated equipment is required; the evacuation process can cause huge waste of liquid oxygen; the liquid oxygen storage tank must be resistant to negative pressure; oxygen is very dangerous, and evacuation equipment acts on oxygen, so that huge potential safety hazards exist; there is leakage to the liquid oxygen storage tank to contaminate the liquid oxygen.

The large helium refrigeration system can also provide supercooling for liquid oxygen, but the working temperature area of the conventional helium refrigeration system is between the room temperature and the supercooling liquid oxygen area, so that the refrigeration efficiency is low and the power consumption is extremely high. In addition, there are also cold helium compressors operating in the liquid hydrogen temperature range, and even in the liquid helium temperature range, which compressors have gas inlets and outlets significantly below room temperature.

Prior to launching of the cryogenic rocket, the fluid stored at the launch site on the ground comprises: liquid fuels (liquid hydrogen, liquid methane, or kerosene), liquid oxygen, liquid nitrogen, high pressure helium gas, and the like. The liquid nitrogen is mainly used for gas replacement, propellant supercooling and the like of containers and pipeline systems, and the helium is used for purification, pressurization and the like of storage tanks and pipelines.

Disclosure of Invention

In order to overcome the defects of the prior art, the invention aims to provide a non-negative pressure liquid oxygen high supercooling degree obtaining system, which combines liquid nitrogen precooling and cold helium compressor refrigeration, so that the field preparation of a launching field of liquid oxygen with the supercooling degree lower than 64K can be realized without a vacuumizing device and a negative pressure heat exchange device.

In order to achieve the purpose, the invention adopts the technical scheme that:

a non-negative pressure liquid oxygen high supercooling degree acquisition system comprises a liquid oxygen storage tank 1, wherein a top pressurizing port of the liquid oxygen storage tank 1 is connected with an outlet of a high-pressure helium bottle 6 through a back pressure regulating valve 8 and a pressure release valve 7; an outlet at the bottom of the liquid oxygen storage tank 1 is connected with an inlet of the liquid oxygen leakage valve 2, an outlet of the liquid oxygen leakage valve 2 is connected with an inlet of a circulating pump 3, an outlet of the circulating pump 3 is connected with a liquid oxygen side inlet of the oxygen-helium heat exchanger 4, a liquid oxygen side outlet of the oxygen-helium heat exchanger 4 is connected with an inlet of a backflow check valve 5, and an outlet of the backflow check valve 5 is connected with a backflow port at the top of the liquid oxygen storage tank 1;

a helium side outlet of the oxygen-helium heat exchanger 4 is connected with an inlet of a cold helium compressor 13, an outlet of the cold helium compressor 13 is connected with a helium side inlet of a liquid nitrogen bath type heat exchanger 11, a helium side outlet of the liquid nitrogen bath type heat exchanger 11 is connected with an inlet of a helium expander 14, and an outlet of the helium expander 14 is connected with a helium side inlet of the oxygen-helium heat exchanger 4;

a liquid nitrogen inlet of the liquid nitrogen bath type heat exchanger 11 is connected with an outlet at the bottom of the liquid nitrogen storage tank 9 through a first liquid level regulating valve 10, and a nitrogen outlet of the liquid nitrogen bath type heat exchanger 11 is emptied through a first nitrogen gas leakage valve 12.

A recooling device 15 is additionally arranged, a first helium inlet of the recooling device 15 is connected with a helium side outlet of the oxygen-helium heat exchanger 4, a first helium outlet of the recooling device 15 is connected with an inlet of a cold helium compressor 13, an outlet of the cold helium compressor 13 is connected with a helium side inlet of a liquid nitrogen bath type heat exchanger 11, a helium side outlet of the liquid nitrogen bath type heat exchanger 11 is connected with a second helium inlet of the recooling device 15, a second helium outlet of the recooling device 15 is connected with an inlet of a helium expander 14, and an outlet of the helium expander 14 is connected with a side inlet of the oxygen-helium heat exchanger 4.

Introducing a liquid nitrogen bath type subcooler 17, wherein a liquid oxygen inlet of the liquid nitrogen bath type subcooler 17 is connected with an outlet of the circulating pump 3, a liquid oxygen outlet of the liquid nitrogen bath type subcooler 17 is connected with an inlet of a backflow check valve 5 through a second stop valve 19, an inlet of the backflow check valve 5 is connected with an outlet of a first stop valve 18, an inlet of the first stop valve 18 is connected with a liquid oxygen side outlet of the oxygen-helium heat exchanger 4, and a liquid oxygen side inlet of the oxygen-helium heat exchanger 4 is connected with an outlet of the circulating pump 3 through a bypass valve 16; the liquid nitrogen inlet of the liquid nitrogen bath type subcooler 17 is connected with the outlet of the liquid nitrogen storage tank 9 through a second liquid level regulating valve 20, and the nitrogen outlet of the liquid nitrogen bath type subcooler 17 is emptied through a second nitrogen gas discharge valve 21.

The utility model provides a big supercooling degree of liquid oxygen acquisition system of no negative pressure, adopts liquid oxygen filling process to realize big supercooling degree and obtains, includes liquid oxygen storage tank 1, and the pressure boost exit linkage pressure boost relief valve 22 entry in 1 bottom of liquid oxygen storage tank, pressure boost relief valve 22 exit linkage empty bath vaporizer 23 entry, empty bath vaporizer 23 export is through the top pressure boost mouth of pressure boost check valve 24 connection liquid oxygen storage tank 1, and liquid oxygen storage tank 1 bottom is higher than empty bath vaporizer 23 top, relies on gravity to realize supplying liquid.

An outlet at the bottom of the liquid oxygen storage tank 1 is connected with an inlet of a liquid oxygen leakage valve 2, an outlet of the liquid oxygen leakage valve 2 is connected with a liquid oxygen side inlet of an oxygen-helium heat exchanger 4, a liquid oxygen side outlet of the oxygen-helium heat exchanger 4 is connected with an inlet of a filling valve 25, an outlet of the filling valve 25 is connected with a filling port at the bottom of an arrow upper storage tank 26, and a pressurizing port at the top of the arrow upper storage tank 26 is connected with a high-pressure helium bottle 6 through a back pressure regulating valve 8, a pressure release valve;

a helium side outlet of the oxygen-helium heat exchanger 4 is connected with an inlet of a cold helium compressor 13, an outlet of the cold helium compressor 13 is connected with a helium side inlet of a liquid nitrogen bath type heat exchanger 11, a helium side outlet of the liquid nitrogen bath type heat exchanger 11 is connected with an inlet of a helium expander 14, and an outlet of the helium expander 14 is connected with a helium side inlet of the oxygen-helium heat exchanger 4; a liquid nitrogen inlet of the liquid nitrogen bath type heat exchanger 11 is connected with an outlet at the bottom of the liquid nitrogen storage tank 9 through a first liquid level regulating valve 10, and a nitrogen outlet of the liquid nitrogen bath type heat exchanger 11 is emptied through a first nitrogen gas leakage valve 12.

A saturated nitrogen bath type subcooler 28 is added in front of the oxygen-helium heat exchanger 4, a liquid oxygen side inlet of the saturated nitrogen bath type subcooler 28 is connected with an outlet of the liquid oxygen leakage valve 2, a liquid oxygen side outlet of the saturated nitrogen bath type subcooler 28 is connected with a liquid oxygen side inlet of the oxygen-helium heat exchanger 4, a liquid oxygen side outlet of the oxygen-helium heat exchanger 4 is connected with an inlet of the filling valve 25, a liquid nitrogen side inlet of the saturated nitrogen bath type subcooler 28 is connected with a bottom outlet of the liquid nitrogen storage tank 9 through a liquid nitrogen control valve 27, and a nitrogen outlet of the saturated nitrogen bath type subcooler 28 is emptied through a third nitrogen leakage valve 29.

The liquid oxygen storage tank 1 is vertically or horizontally arranged, is made of stainless steel, adopts vacuum powder heat insulation or vacuum multilayer heat insulation, and has the pressure bearing higher than 1 MPa.

The circulating pump 3 is soaked and cooled to ensure that the pump body is at the liquid oxygen temperature, and the pressurizing pressure head of the pump is larger than the liquid oxygen circulating flow pressure drop and the gravity pressure drop when the liquid oxygen storage tank 1 is at the lowest liquid level; the circulating pump 3 or adopt the submerged pump structure, and at this moment, the circulating pump 3 is arranged in the liquid oxygen storage tank 1 and is positioned in front of the liquid oxygen bleeder valve 2.

The oxygen-helium heat exchanger 4 adopts a shell-tube type, plate type and plate-fin type dividing wall type heat exchanger structure, and a helium side flow channel is provided with a heat exchange strengthening structure of fins; the exterior of the heat exchanger is filled with pearly-lustre sand for heat insulation.

The backflow check valve 5 is of a one-way valve structure, and the flow direction is from the oxygen-helium heat exchanger 4 to the liquid oxygen storage tank 1.

The high-pressure helium bottle 6 adopts a parallel structure of high-pressure gas bottle groups, helium is stored at normal temperature, and the pressure is not lower than 2 MPa; the opening degree of the back pressure regulating valve 8 is regulated according to the pressure after the valve, namely the internal pressure of the liquid oxygen storage tank 1, and the back pressure of the back pressure regulating valve 8 is set to be more than the ambient pressure plus 500 Pa.

The cold helium compressor 13 is of a centrifugal structure, the inlet pressure is greater than 0.1MPa, and the pressure ratio is not less than 3.

The liquid nitrogen bath type heat exchanger 11 adopts a shell-and-tube heat exchanger structure, helium is arranged on the tube side, and liquid nitrogen is arranged on the shell side; the helium pipe adopts a heat exchange strengthening structure of a snakelike coil pipe and an internal thread pipe; the length of the helium pipe is set by that the temperature of outlet helium is lower than 80K; the shell side liquid level is regulated by a first liquid level regulating valve 10.

The helium expander 14 adopts a centrifugal type, axial flow type or piston type structure, and the pressure after expansion is more than 0.1 MPa.

The cold helium compressor 13, the liquid nitrogen bath type heat exchanger 11, the helium expander 14, the connecting pipeline and the valve are all wrapped in a stacked heat insulation mode, and are respectively wrapped in a heat insulation mode or are integrally insulated after being integrated.

The invention has the beneficial effects that:

the invention adopts the liquid nitrogen resource with sufficient emission field as the cold source, combines the characteristic that the cold helium compressor is suitable for the work of the low-temperature area, limits the working temperature area of the refrigerating system below the liquid nitrogen temperature area, and obviously improves the refrigerating efficiency; the method makes full use of the conditions of the transmitting field, and reduces the equipment investment and the transformation cost for obtaining the liquid oxygen with large supercooling degree.

The invention can prepare deep super-cooling liquid oxygen with the temperature lower than 64K, and the lowest temperature can approach the triple point temperature of oxygen, thereby furthest excavating the performance advantage of the super-cooling propellant.

In the process of obtaining the large supercooling degree of the liquid oxygen, the invention does not adopt the vacuumizing equipment and the negative pressure heat exchanger which are necessary for the conventional supercooling, effectively avoids the potential safety hazard caused by directly vacuumizing the oxygen, has no negative pressure in the whole system, is beneficial to reducing the weight of the structure and the cost, and can avoid the liquid oxygen pollution caused by leakage in the process of obtaining the supercooled liquid oxygen.

The compressor, the expander and the like adopted by the invention all use helium as working fluid, so that the equipment is reliable in operation and has no potential safety hazard.

According to the invention, helium is used as the intermediate secondary refrigerant to realize supercooling of oxygen, and the helium is in contact with the oxygen, so that even if leakage occurs, no safety risk is generated, and liquid oxygen is not polluted; in addition, when cold helium gas exchanges heat with liquid oxygen, the heat exchange rate at the helium side is easier to control, the quantitative obtaining of the supercooling target temperature is facilitated, and the ice blockage hazard at the liquid oxygen side is avoided.

In conclusion, the invention has the advantages of simple structure, reliable operation, larger obtainable supercooling degree, low investment and operation cost, no potential safety hazard and the like, and has considerable application prospect.

Drawings

Fig. 1 is a schematic structural diagram of embodiment 1 of the present invention.

Fig. 2 is a schematic structural diagram of embodiment 2 of the present invention.

Fig. 3 is a schematic structural diagram of embodiment 3 of the present invention.

Fig. 4 is a schematic structural diagram of embodiment 4 of the present invention.

Fig. 5 is a schematic structural diagram of embodiment 5 of the present invention.

Detailed Description

The invention is described in detail below with reference to the figures and examples.