Novel liquid oxygen evaporator

Abstract

The utility model relates to a novel liquid oxygen evaporator which comprises a shell and a pipeline, a heat exchange cavity is formed in the shell, the pipeline is arranged in the heat exchange cavity, the pipeline is provided with a separation connector, the separation connector is connected with a separator, and the separator is used for achieving gas-liquid separation on the pipeline in the heat exchange cavity. According to the utility model, the gas phase separator is arranged on the pipeline to timely separate and discharge oxygen gas in the pipeline, so that two-phase balance in the pipeline is maintained, and gas blockage caused by a large amount of oxygen gas generated when liquid oxygen reaches a boiling point after being heated is avoided.

Description

Technical Field

[0001] This utility model relates to the field of liquid nitrogen evaporator technology, specifically to a novel liquid oxygen evaporator. Background Technology

[0002] The operating principle of a liquid oxygen evaporator is to convert a liquid substance into a gaseous substance. When liquid oxygen enters the evaporator, it exchanges heat with the outside environment and is thus heated. When the temperature of the liquid oxygen rises above its boiling point, its surface gradually evaporates, forming gaseous oxygen.

[0003] In a liquid oxygen evaporator, liquid and gaseous oxygen interact through a process called "heat exchange." Specifically, the heat exchanger extracts gaseous oxygen from the surface of the liquid oxygen and transfers it to the outside via a heat pipe or other type of heat transfer device. The heat generated during this heat exchange is transferred to the outside environment, allowing the liquid oxygen to evaporate while simultaneously providing some thermal energy to the surroundings to prevent excessive heat from causing a hazard during rocket launch.

[0004] In liquid oxygen evaporators, an excessively high gas-phase ratio can easily occur within the tube bundle. This gas can block the flow channels within the tube bundle, causing liquid oxygen to stagnate or backflow within the pipes, disrupting the uniform phase change. This also makes it easy for liquid stagnation surfaces to form in the low-speed region of the pipes. Liquid oxygen stagnation at these points increases thermal resistance, negatively impacting the evaporation and heating efficiency. Utility Model Content

[0005] The purpose of this invention is to solve the technical problem that existing evaporators easily form stagnation in the pipes, affecting the evaporation effect. It provides a novel liquid nitrogen evaporator that can perform gas-liquid separation within the pipes inside the shell, maintaining the two-phase balance within the pipes and avoiding stagnation that affects the evaporation effect. The main concept is as follows:

[0006] A novel liquid oxygen evaporator includes a shell and pipes. The shell contains a heat exchange chamber, within which pipes are installed. These pipes are equipped with separation interfaces connected to a separator, which performs gas-liquid separation within the heat exchange chamber. To prevent the generation of large amounts of oxygen gas that could cause gas blockage when liquid oxygen reaches its boiling point after heating, a gas-phase separator is installed on the pipes to promptly separate and discharge the oxygen gas, maintaining the two-phase balance within the pipes.

[0007] Preferably, the pipeline adopts a reciprocating arrangement structure, including a bend and a horizontal flow section. The separation interface is installed at one end of the horizontal flow section near the bend, and the two ends of the separation interface are connected to the horizontal flow section of the pipeline via sealing flanges. This design separates the oxygen gas after it passes through the bend, allowing the gas phase in the bend to first generate bubbles on the wall surface, forming nucleated boiling, disturbing and breaking down the stagnant layer in the bend, thus increasing the heat transfer coefficient of the bend before the gas phase is collected.

[0008] Preferably, the bending section adopts a U-shaped transition and includes two right-angle bends. This design can buffer the flow rate at the bending section and allow for sufficient heat exchange of liquid oxygen within the bending section. Furthermore, the use of right-angle bends in the bending section enhances the strength of the tube bundle.

[0009] Preferably, the separator includes a separation chamber, a feed inlet, a discharge inlet, and an exhaust valve. The feed inlet and discharge inlet are located at the bottom of the separation chamber, and the exhaust valve is located at the top of the separation chamber, connected to an external gas pipe. Since the pressure in the tube side and shell side of the liquid oxygen evaporator is the same as the external gas pressure, the two phases entering the separation chamber through the feed inlet in the pipeline will have their liquid phase re-enter the pipeline through the discharge inlet under gravity. The gas phase will naturally rise in the separation chamber and enter the exhaust valve to be separated from the external gas pipe.

[0010] Preferably, the separation interface includes a main flow pipe and a branch flow pipe. The branch flow pipe includes an inlet pipe that enters the feed inlet and an outlet pipe that enters the discharge outlet. The inlet pipe and the outlet pipe are perpendicular to the outer contour surface of the main flow pipe, and the inner diameter of the inlet pipe and the outlet pipe is smaller than that of the main flow pipe.

[0011] Preferably, the separation interface further includes a necking baffle and a balancing pipe. The necking baffle is respectively disposed in the main flow pipe between the inlet pipe and the outlet pipe, and the necking baffle is connected by the balancing pipe, the inner diameter of which is smaller than the inner diameter of the main flow pipe. In order to balance the pressure inside the distribution pipe and allow some liquid oxygen to enter the separator, the main flow pipe is necked, so that the liquid oxygen entering the separation interface passes through the main flow pipe, part of which enters the balancing pipe, and part of which enters the diversion pipe under the resistance of the necking baffle.

[0012] Preferably, the separation chamber is provided with a flow guide slope, which connects the feed inlet and the discharge inlet. The feed inlet is higher than the discharge inlet on the flow guide slope. The flow guide slope not only guides the internal liquid phase but also increases the flow area of ​​the liquid phase in the separation chamber, thereby improving the gas phase separation effect.

[0013] Preferably, the shell adopts a cylindrical structure, with end caps at both ends. The end caps have installation holes for pipe insertion. The outer contour surface of the shell is provided with a medium inlet and a medium outlet. The medium inlet is used to input heat exchange medium into the heat exchange cavity inside the shell.

[0014] Preferably, the heat exchange cavity is provided with multiple heat exchange fins inside, which are used to plan the heat exchange path of the heat exchange cavity.

[0015] The beneficial effects of this utility model are as follows:

[0016] To prevent the production of large amounts of oxygen gas and subsequent gas blockage when liquid oxygen reaches its boiling point after heating, a gas phase separator is installed on the pipeline to promptly separate and discharge the oxygen gas inside the pipeline, maintaining the two-phase balance within the pipeline. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the structure of this utility model.

[0018] Figure 2 This is a top view of the structure of this utility model.

[0019] Figure 3 This is a schematic diagram of the separator of this utility model.

[0020] The reference numerals in the attached drawings include: 1. Shell; 11. Heat exchange chamber; 12. Heat exchange fins; 13. End cap; 14. Medium inlet; 15. Medium outlet; 2. Pipe; 21. Bend; 211. Right-angle bend; 22. Horizontal flow section; 3. Separation interface; 31. Main flow pipe; 32. Inlet pipe; 33. Outlet pipe; 34. Necked-off side; 35. Balance pipe; 4. Separator; 41. Separation chamber; 42. Feed inlet; 43. Discharge inlet; 44. Air outlet valve; 45. Guide slope. Detailed Implementation

[0021] To make the objectives, technical solutions, and advantages of the embodiments clearer, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. When the following description refers to the drawings, unless otherwise indicated, the same numbers in different drawings represent the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with this disclosure. Rather, they are merely examples of apparatuses and methods consistent with some aspects of this disclosure as detailed in the appended claims.

[0022] In this disclosure, unless otherwise stated, directional terms such as "inner" and "outer" are defined based on the contours of the corresponding components. Terms such as "first" and "second" used in this disclosure are for distinguishing one element from another and do not imply sequence or importance.

[0023] like Figures 1-3 As shown, a novel liquid oxygen evaporator includes a shell 1 and a pipe 2. The shell 1 has a heat exchange chamber 11, and the pipe 2 is installed inside the heat exchange chamber 11. The pipe 2 is equipped with a separation interface 3, which is connected to a separator 4. The separator 4 is used to achieve gas-liquid separation in the pipe 2 inside the heat exchange chamber 11.

[0024] To prevent the liquid oxygen from generating a large amount of oxygen gas when it reaches its boiling point after heating, which would cause gas blockage and form a thick stagnant layer, a gas phase separator 4 is installed on pipeline 2 to separate and discharge the oxygen gas in pipeline 2 in a timely manner, thus maintaining the two-phase balance in pipeline 2.

[0025] Pipeline 2 adopts a reciprocating arrangement structure, including a bend 21 and a horizontal flow section 22. A separation interface 3 is installed at one end of the horizontal flow section 22 near the bend 21. The two ends of the separation interface 3 are connected to the horizontal flow section 22 of pipeline 2 via sealing flanges. This design separates the oxygen gas after it passes through the bend 21, allowing the gas phase in the bend 21 to first generate bubbles on the wall surface, forming nucleated boiling. This disturbs and breaks down the stagnant layer in the bend 21, increasing the heat transfer coefficient of the bend 21 before the gas phase is collected.

[0026] The bend 21 adopts a U-shaped transition and includes two right-angle bends 211. This design can buffer the flow rate of the bend 21 and allow the liquid oxygen in the bend 21 to exchange heat fully. At the same time, the bend 21 composed of right-angle bends 211 can improve the strength of the tube bundle.

[0027] The separator 4 includes a separation chamber 41, a feed inlet 42, a discharge inlet 43, and an exhaust valve 44. The feed inlet 42 and discharge inlet 43 are located at the bottom of the separation chamber 41, and the exhaust valve 44 is located at the top of the separation chamber 41, connecting to an external gas pipe. Since the pressure in the tube side and shell side of the liquid oxygen evaporator is the same as the external gas pressure, the two phases entering the separation chamber 41 through the feed inlet 42 in the pipeline 2 will flow back into the pipeline 2 through the discharge inlet 43 under the action of gravity, while the gas phase will naturally rise in the separation chamber 41 and enter the exhaust valve 44 to be separated from the external gas pipe.

[0028] In order to allow the external gas pipe connected to the outlet valve 44 of the separator 4 to be led out to the outside of the housing 1, the upper end face of the housing in this design is provided with a mounting hole, which allows the outer wall of the separator 4 to extend to the outside of the evaporator through the mounting hole. The separator 4 is sealed between the mounting hole and the mounting hole by a flange connection to prevent the heat exchange medium inside the housing from leaking.

[0029] Liquid oxygen evaporators are widely used in applications requiring the conversion of liquid oxygen into gaseous oxygen, such as the vaporization supply after liquid oxygen storage and transportation, processes in industrial production that require gaseous oxygen as a raw material or auxiliary gas, and liquid oxygen supply systems in the medical field. The discharged oxygen is separated in a separator installed in the middle section of the pipeline and collected uniformly through an external gas pipe. The oxygen separated by the two-phase separator connected to the outlet at the end of pipeline 2 is then recovered into the gas cylinder.

[0030] The separation interface 3 includes a main flow pipe 31 and a branch flow pipe. The branch flow pipe includes an inlet pipe 32 that enters the feed inlet 42 and an outlet pipe 33 that enters the discharge outlet 43. The inlet pipe 32 and the outlet pipe 33 are perpendicularly arranged on the outer contour surface of the main flow pipe 31, and the inner diameter of the inlet pipe 32 and the outlet pipe 33 is smaller than that of the main flow pipe 31.

[0031] Since the separator is located in the middle of the pipe inside the evaporator, the separation interface 3 connected to the separator allows the flow channel to pass through the main pipe 31 and the branch pipe, so that a part of the liquid oxygen is separated into gas and liquid, and a part of the liquid oxygen carries the evaporated oxygen in the pipe 2 to achieve gas phase balance inside the pipe.

[0032] The separation interface 3 also includes a necking baffle 34 and a balancing pipe 35. The necking baffle 34 is respectively disposed on the main flow pipe 31 between the inlet pipe 32 and the outlet pipe 33. The necking baffle 34 is connected by the balancing pipe 35, the inner diameter of which is smaller than the inner diameter of the main flow pipe 31. In order to balance the pressure inside the pipe and allow some liquid oxygen to enter the separator 4, the main flow pipe 31 is necked. This allows the liquid oxygen entering the separation interface 3 to pass through the main flow pipe 31, with part entering the balancing pipe 35 and part entering the diversion pipe under the resistance of the necking baffle 34.

[0033] Therefore, each separation interface 3 is provided with two main flow pipes 31, two necking baffles 34, and one balance pipe 35. The outer contour walls of the main flow pipes 31 are connected to the inlet pipe 32 and the outlet pipe 33, respectively. The two main flow pipes 31 are coaxially arranged. The farthest two ends of the main flow pipes 31 are connected to the pipe 2, and the closest two ends of the main flow pipes 31 are connected to the necking baffles 34, respectively. The necking baffles 34 of this scheme adopt a flared shape and include a large-diameter connection end and a small-diameter connection end. The inner diameter of the large-diameter connection end is larger than that of the small-diameter connection end. The large-diameter connection end of the necking baffles 34 is connected to the main flow pipes 31, so that the small-diameter connection ends of the two necking baffles 34 are connected to the two ends of the balance pipe 35, forming a necking effect.

[0034] The separation chamber 41 is provided with a flow guide slope 45, which connects the feed port 42 and the discharge port 43. The feed port 42 is higher than the discharge port 43 on the flow guide slope 45. The flow guide slope 45 not only guides the liquid phase inside, but also increases the flow area of ​​the liquid phase in the separation chamber 41, thereby improving the gas phase separation effect.

[0035] Separators 4 are evenly arranged on the pipe 2 inside the evaporator to avoid gas-liquid stratification in the pipe and local stagnation. Separator 4 is an air separation device that quickly separates the oxygen carried by the liquid oxygen after evaporation in the pipe.

[0036] The shell 1 adopts a cylindrical structure. Both ends of the shell 1 are provided with end caps 13. The end caps 13 have installation holes for inserting pipes 2. The outer contour surface of the shell 1 is provided with a medium inlet 14 and a medium outlet 15. The medium inlet 14 is used to input heat exchange medium into the heat exchange cavity 11 inside the shell 1.

[0037] The heat exchange cavity 11 is equipped with multiple heat exchange fins 12, which are used to plan the heat exchange path of the heat exchange cavity 11. Liquid nitrogen is introduced into the pipe 22, and the heat exchange medium is introduced into the heat exchange cavity 12 of the shell 1 through the medium inlet 14. The heat exchange medium can be hot water, steam, etc. The temperature of the heat exchange medium is higher than the boiling point of liquid nitrogen. The temperature difference between the heat exchange medium and liquid oxygen (-183℃) is used to transfer heat to the liquid nitrogen inside the pipe through the pipe wall. After absorbing heat, the temperature of the liquid nitrogen gradually rises to the boiling point and begins to evaporate, changing from a liquid state to a gaseous state.

[0038] Meanwhile, the heat exchange fins 12 are staggered to form an S-shaped heat exchange channel, which makes the heat exchange medium form a specific flow path in the heat exchange cavity 11, enhances the convective heat transfer between the heat exchange medium and the pipe, further improves the heat transfer efficiency of the evaporator, and ensures that liquid nitrogen can be rapidly and stably evaporated into gaseous nitrogen to meet the demand for gaseous nitrogen in production or other application scenarios.

[0039] The above descriptions are merely embodiments of this utility model, and common knowledge regarding specific structures and characteristics is not elaborated upon here. It should be noted that those skilled in the art can make various modifications and improvements without departing from the structure of this utility model, and these should also be considered within the scope of protection of this utility model. These modifications will not affect the effectiveness of the implementation of this utility model or the practicality of the patent. The scope of protection claimed in this application shall be determined by the content of its claims, and the specific embodiments described in the specification can be used to interpret the content of the claims.

Claims

1. A novel liquid oxygen evaporator comprising a housing (1) and a duct (2), characterized in that: The shell (1) has a heat exchange chamber (11) inside, and a pipe (2) is installed inside the heat exchange chamber (11). The pipe (2) is equipped with a separation interface (3), which is connected to a separator (4). The separator (4) is used to achieve gas-liquid separation of the pipe (2) inside the heat exchange chamber (11).

2. A novel liquid oxygen evaporator as claimed in claim 1, wherein: The pipe (2) adopts a reciprocating arrangement structure. The pipe (2) includes a bending section (21) and a horizontal section (22). The separation interface (3) is installed at one end of the horizontal section (22) of the pipe (2) near the bending section (21). The two ends of the separation interface (3) and the horizontal section (22) of the pipe (2) are connected by a sealing flange.

3. A novel liquid oxygen evaporator as claimed in claim 2, wherein: The bending section (21) adopts a U-shaped transition and includes two right-angle bends (211).

4. A novel liquid oxygen evaporator as claimed in claim 1, wherein: The separator (4) includes a separation chamber (41), a feed port (42), a discharge port (43), and an air valve (44). The bottom of the separation chamber (41) is provided with the feed port (42) and the discharge port (43), and the top of the separation chamber (41) is provided with the air valve (44), which is connected to an external air pipe.

5. A novel liquid oxygen evaporator as claimed in claim 1, wherein: The separation interface (3) includes a main pipe (31) and a branch pipe. The branch pipe includes an inlet pipe (32) that enters the feed inlet (42) and an outlet pipe (33) that enters the discharge inlet (43). The inlet pipe (32) and the outlet pipe (33) are perpendicularly arranged on the outer contour surface of the main pipe (31). The inner diameter of the inlet pipe (32) and the outlet pipe (33) is smaller than that of the main pipe (31).

6. A novel liquid oxygen evaporator as claimed in claim 5, wherein: The separation interface (3) also includes a necking baffle (34) and a balance tube (35). The necking baffle (34) is respectively set in the main stream pipe (31) between the inlet pipe (32) and the outlet pipe (33). The necking baffle (34) is connected through the balance tube (35). The inner diameter of the balance tube (35) is smaller than the inner diameter of the main stream pipe (31).

7. A novel liquid oxygen evaporator as claimed in claim 4, wherein: The separation chamber (41) is provided with a flow guide slope (45), which connects the feed port (42) and the discharge port (43). The feed port (42) is at a higher height than the discharge port (43) on the flow guide slope (45).

8. A novel liquid oxygen evaporator as claimed in claim 1, wherein: The shell (1) adopts a cylindrical structure. The two ends of the shell (1) are provided with end caps (13). The end caps (13) have installation holes for inserting pipes (2). The outer contour surface of the shell (1) is provided with a medium inlet (14) and a medium outlet (15). The medium inlet (14) is used to input heat exchange medium into the heat exchange cavity (11) inside the shell (1).

9. A novel liquid oxygen evaporator as claimed in claim 8, wherein: The heat exchange cavity (11) is provided with multiple heat exchange fins (12) inside, which are used to plan the heat exchange path of the heat exchange cavity (11).

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