A real-time vaporization system for large-flow cryogenic media

Abstract

The present invention discloses a large-flow cryogenic medium real-time vaporization system, which generates 373K~500K low-temperature water vapor through the combustion of hydrocarbon fuel, air / oxygen, and water, and then vaporizes hundreds of kilograms of high-pressure liquid nitrogen or liquid oxygen into normal-temperature gas in real time through a partition-type heat exchange tube. The present invention is composed of a low-total-temperature gas generator, a shell, and a steam drum. The shell is provided with a first serpentine flow channel and a second serpentine flow channel, and a heat exchange structure is provided between the first serpentine flow channel and the second serpentine flow channel; the first high-temperature medium inlet is connected to the first end of the first serpentine flow channel, and the first normal-temperature medium outlet is connected to the second end of the first serpentine flow channel; the second low-temperature medium inlet is connected to the first end of the second serpentine flow channel, and the second normal-temperature medium outlet is connected to the second end of the second serpentine flow channel. The present invention is applied to the field of cryogenic medium vaporization, and can realize the liquid storage and gaseous supply of large-flow high-pressure cryogenic medium, taking into account the safety and reliability of system operation.

Description

Technical Field

[0001] This project involves a large-scale high-altitude simulation test bench for aerospace engines, specifically a large-flow cryogenic medium real-time vaporization system. Background Art

[0002] The high-altitude simulation test bench for aerospace engines can create a high-speed flow and a high-altitude low static pressure environment on the ground, and plays a vital role in the whole process of engine pre-research, prototype, test, finalization, and batch production. High-pressure oxygen or nitrogen with a large flow rate is an essential medium for the operation of large-scale high-altitude simulation test benches, which is generally divided into two types of storage and supply methods: normal temperature gas and low-temperature liquid. However, the high-pressure oxygen or nitrogen system can be used at any time and has high operating efficiency, but there is an adiabatic degassing effect when it is supplied at a large flow rate, and the gas temperature in the storage tank drops sharply as the pressure drops rapidly. Therefore, the gas utilization rate is only 30%~60%, resulting in a large scale of gas source storage tanks for large-scale high-altitude simulation test benches and high construction costs. The cryogenic liquid nitrogen or liquid oxygen system has the advantages of small storage tank scale and high medium utilization rate (generally 70%-80%), but there are situations such as the supply pipeline needs to be insulated and pre-cooled before operation, resulting in high construction costs, large consumption of cryogenic media, and low operating efficiency. If large-flow high-pressure oxygen, nitrogen and other working fluids can achieve liquid storage and real-time gaseous supply, it can take into account the advantages of high tank utilization, low medium consumption, and high operating efficiency, greatly reducing the construction cost of the test bench and increasing operating benefits.

[0003] Liquid nitrogen or liquid oxygen with a flow rate range of 10-100kg / s is vaporized at room temperature, and the instantaneous heat exchange power is as high as 4~40MW. The traditional air-cooled, water-bath and electric-heated vaporizers in the industry are difficult to meet the use requirements of long-term stable vaporization. For example, the Chinese invention patent application with patent publication number CN104034018A proposes a direct-fired atmospheric liquid vaporizer, which uses a high-temperature flame to directly bake the high-pressure liquid nitrogen pipeline to achieve rapid vaporization. There are problems such as large temperature difference between gas and liquid nitrogen, resulting in large thermal stress of the high-pressure pipeline, short working life, and high risk of system explosion when using liquid oxygen working fluid. Summary of the invention

[0004] In view of the deficiencies in the above-mentioned prior art, the present invention provides a large-flow cryogenic medium real-time vaporization system, which generates a large-flow cryogenic water vapor through the combustion of hydrocarbon fuel, oxidant and water, and utilizes the steam sensible heat, evaporation latent heat, liquid sensible heat and other energies in the low-temperature water vapor to vaporize hundreds of kilograms of cryogenic media such as liquid nitrogen or liquid oxygen into room temperature gas in real time, thereby realizing liquid storage and gaseous supply of cryogenic media, reducing the total volume of storage tanks, reducing gas source construction and operating costs, and taking into account the safety and reliability of system operation.

[0005] To achieve the above-mentioned object, the present invention provides a large-flow cryogenic medium real-time vaporization system, comprising a hollow shell, wherein a first serpentine flow channel and a second serpentine flow channel which are not connected to each other are provided in the shell, and a heat exchange structure is provided between the first serpentine flow channel and the second serpentine flow channel, wherein the heat exchange structure comprises a plurality of heat exchange tubes which are parallel to each other and are distributed in a linear array or a rectangular array;

[0006] The shell is provided with a first high-temperature medium inlet, a first normal-temperature medium outlet, a second low-temperature medium inlet and a second normal-temperature medium outlet;

[0007] The first high-temperature medium inlet is connected to the first end of the first serpentine flow channel, and the first normal-temperature medium outlet is connected to the second end of the first serpentine flow channel;

[0008] The second low-temperature medium inlet is connected to the first end of the second serpentine flow channel, and the second normal-temperature medium outlet is connected to the second end of the second serpentine flow channel;

[0009] The first high-temperature medium inlet and the second normal-temperature medium outlet are located at a first end of the shell, and the second low-temperature medium inlet and the first normal-temperature medium outlet are located at a second end of the shell.

[0010] In one embodiment, two first partitions are provided in the shell to divide the internal space of the shell into an upper steam drum cavity, a heat exchange cavity and a lower steam drum cavity;

[0011] A plurality of staggered baffles are provided in the heat exchange cavity to divide the heat exchange cavity to form the first serpentine flow channel;

[0012] There are multiple heat exchange structures, and each of the heat exchange structures is sequentially arranged in the heat exchange cavity, each of the heat exchange structures includes a plurality of heat exchange tubes that are parallel to each other and distributed in a linear array or a rectangular array, and both ends of each heat exchange tube are respectively connected to the two first partitions;

[0013] A second partition is provided in the upper steam drum cavity and the lower steam drum cavity to divide the upper steam drum cavity and the lower steam drum cavity into a plurality of steam drums;

[0014] The same end of all the heat exchange tubes in two adjacent heat exchange structures is connected to the same steam drum, so that the heat exchange tubes cooperate with each steam drum to form the second serpentine flow channel.

[0015] In one embodiment, a plurality of fins are provided on the outer wall of the heat exchange tube at intervals along the circumferential direction.

[0016] In one of the embodiments, in the same heat exchange structure, parts of the fins on two adjacent heat exchange tubes are fixedly connected by a stabilizing bracket.

[0017] In one embodiment, in the same heat exchange structure, the diameters of the heat exchange tubes are the same;

[0018] In the direction from the first end of the second serpentine flow channel to the second end of the second serpentine flow channel, the diameters of the heat exchange tubes in each of the heat exchange structures increase sequentially.

[0019] In one embodiment, ribs or ribs are provided in the steam drum to enhance the strength of the high-pressure structure.

[0020] In one embodiment, the heat exchange tube is made of stainless steel or copper, and the fin is made of stainless steel or aluminum or copper.

[0021] In one embodiment, the large-flow low-temperature medium real-time vaporization system further includes a gas generator, and the first high-temperature medium inlet is connected to the gas generator.

[0022] The gas generator first uses alcohol or kerosene or methane or isobutane, liquid / gas oxygen or air, and water to burn to generate gas with a temperature of 800K~2000K and a pressure of 2MPa~3MPa, and then adds water to mix and evaporate into low-temperature water vapor with a temperature of 373K~500K and a pressure of ≤0.5MPa.

[0023] Compared with the prior art, the present invention has the following beneficial technical effects:

[0024] 1. The present invention uses countercurrent heat exchange to efficiently vaporize the low-temperature medium, realizing large flow and long-term conversion from liquid storage to gaseous transportation, thereby reducing the construction and operation costs of the gas supply system;

[0025] 2. In the preferred embodiment of the present invention, heat exchange tubes of different diameters are used in different heat exchange structures, and the flow area of ​​the pipeline is changed in real time according to the changes in the pressure and temperature of the low-temperature medium, thereby reducing the thermal resistance and improving the heat exchange efficiency;

[0026] 3. In the preferred embodiment of the present invention, 373~500K water vapor generated by combustion of a gas generator is used as a heat exchange medium, and the steam sensible heat, evaporation latent heat and liquid sensible heat of the high-temperature medium are utilized to reduce the steam flow rate. In addition, the water vapor temperature is lower than that of the high-temperature fuel gas, thereby avoiding direct baking of the high-pressure pipeline and realizing a long-term steady-state supply of the gas supply system. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the structures shown in these drawings without paying creative work.

[0028] Figure 1 It is an overall axonometric diagram of a large flow rate low temperature medium real-time vaporization system in an embodiment of the present invention;

[0029] Figure 2 It is a partial cross-sectional view of a large flow rate low temperature medium real-time vaporization system in an embodiment of the present invention;

[0030] Figure 3 It is a top perspective view of a large flow rate low temperature medium real-time vaporization system in an embodiment of the present invention;

[0031] Figure 4 It is a front view of the internal structure of the large flow rate low temperature medium real-time vaporization system in the embodiment of the present invention;

[0032] Figure 5 It is a partial structural diagram of a heat exchange tube in an embodiment of the present invention;

[0033] Figure 6 A top view of the internal structure of a large flow rate low temperature medium real-time vaporization system in an embodiment of the present invention;

[0034] Figure 7 A cross-sectional view of a gas generator.

[0035] Figure numbers: shell 1, first high-temperature medium inlet 101, second low-temperature medium inlet 102, first normal-temperature medium outlet 103, second normal-temperature medium outlet 104, heat exchange chamber 105, first partition 2, baffle 3, second partition 4, heat exchange tube 5, fin 501, stabilizing bracket 502, steam drum 6, gas generator 7, fuel inlet 701, water inlet 702, oxidant inlet 703, injector 704, combustion chamber 705, Laval nozzle 706, cooling chamber 707, cooling water inlet 708, water vapor outlet 709.

[0036] The realization of the purpose, functional features and advantages of the present invention will be further explained in conjunction with embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0037] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0038] It should be noted that all directional indications (such as up, down, left, right, front, back, etc.) in the embodiments of the present invention are only used to explain the relative position relationship, movement status, etc. between the components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

[0039] In addition, in the present invention, descriptions such as "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" or "second" may explicitly or implicitly include at least one of the features. In the description of the present invention, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0040] In the present invention, unless otherwise clearly specified and limited, the terms "connection", "fixation", etc. should be understood in a broad sense. For example, "fixation" can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection, an electrical connection, a physical connection, or a wireless communication connection; it can be a direct connection, or an indirect connection through an intermediate medium, or it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0041] In addition, the technical solutions between the various embodiments of the present invention can be combined with each other, but it must be based on the fact that ordinary technicians in the field can implement it. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0042] like Figures 1 to 4 The figure shows a large flow rate low temperature medium real-time vaporization system disclosed in the present embodiment, which mainly includes a hollow shell 1 and a gas generator 7. A first serpentine flow channel and a second serpentine flow channel that are not connected to each other are provided in the shell 1, and a heat exchange structure is provided between the first serpentine flow channel and the second serpentine flow channel, so that the medium with a temperature difference in the first serpentine flow channel and the second serpentine flow channel can exchange heat.

[0043] The shell 1 is provided with a first high-temperature medium inlet 101, a second low-temperature medium inlet 102, a first normal-temperature medium outlet 103 and a second normal-temperature medium outlet 104, and the gas generator 7 is connected to the first high-temperature medium inlet 101. The first high-temperature medium inlet 101 is connected to the first end of the first serpentine flow channel, and the first normal-temperature medium outlet 103 is connected to the second end of the first serpentine flow channel, that is, the first serpentine flow channel is a high-temperature medium end. The high-temperature medium generated by the gas generator 7 flows into the first serpentine flow channel from the first high-temperature medium inlet 101, and is converted into a normal-temperature medium by convection heat exchange with the low-temperature medium in the second serpentine flow channel, and then flows out from the first normal-temperature medium outlet 103. The second low-temperature medium inlet 102 is connected to the first end of the second serpentine flow channel, and the second normal-temperature medium outlet 104 is connected to the second end of the second serpentine flow channel, that is, the second serpentine flow channel is a low-temperature medium end, and the low-temperature medium flows into the second serpentine flow channel from the second low-temperature medium inlet 102, and is converted into a normal-temperature medium by convection heat exchange with the high-temperature medium in the first serpentine flow channel, and then flows out from the second normal-temperature medium outlet 104. Among them, the first high-temperature medium inlet 101 and the second normal-temperature medium outlet 104 are both located at the first end of the shell 1, and the second low-temperature medium inlet 102 and the first normal-temperature medium outlet 103 are both located at the second end of the shell 1, that is, the first end of the first serpentine flow channel and the second end of the second serpentine flow channel are both located at the first end of the shell 1, and the second end of the first serpentine flow channel and the first end of the second serpentine flow channel are both located at the second end of the shell 1. The high-temperature medium and the low-temperature medium adopt countercurrent heat exchange in the shell 1, so that the temperature difference between the high and low temperature media remains relatively stable along the length of the heat exchanger, which is conducive to more uniform heat transfer, improves heat exchange efficiency, realizes efficient vaporization of low-temperature media such as liquid oxygen and liquid nitrogen, realizes large flow and long-term conversion from liquid storage to gaseous transportation, and reduces the construction and operation costs of the gas supply system.

[0044] Two first baffles 2 are provided in the shell 1, and the two first baffles 2 are arranged in parallel and spaced apart, so as to divide the internal space of the shell 1 into an upper steam drum chamber, a heat exchange chamber 105 and a lower steam drum chamber, and the heat exchange chamber 105 is located between the first baffles 2, and the upper steam drum chamber and the lower steam drum chamber are respectively located on the upper and lower sides of the heat exchange chamber 105. A plurality of baffles 3 are provided in the heat exchange chamber 105, and the baffles 3 are connected to the two first baffles 2 in an interlaced and spaced manner, so as to divide the internal space of the heat exchange chamber 105, forming an S-shaped first serpentine flow channel, for example Figure 4 The high-temperature medium flow direction corresponding to the solid line is the first serpentine flow channel.

[0045] In this embodiment, there are multiple heat exchange structures, and each heat exchange structure is arranged in the heat exchange cavity 105 at equal intervals along the length direction of the shell 1, and each heat exchange structure includes a plurality of heat exchange tubes 5 parallel to each other. In the same heat exchange structure, each heat exchange tube 5 is distributed in a linear array or a rectangular array, and at the same time, the two ends of each heat exchange tube 5 are respectively connected to the two first partitions 2. A plurality of second partitions 4 are arranged in the upper steam drum cavity and the lower steam drum cavity, and the second partitions 4 divide the upper steam drum cavity and the lower steam drum cavity into a plurality of steam drums 6. Ribs or ribs can be arranged in the steam drum 6 to enhance the high-pressure structural strength of the steam drum 6. The same end of all heat exchange tubes 5 in two adjacent heat exchange structures is connected to the same steam drum 6. At the same time, for all heat exchange tubes 5 in the heat exchange structure located at the first end, one end thereof does not share a steam drum with other heat exchange structures, that is, there is a steam drum that is only connected to one end of the heat exchange tube 5 in the heat exchange structure located at the first end, and the steam drum is connected to one of the second low-temperature medium inlet 102 and the second normal temperature medium outlet 104. Similarly, for all the heat exchange tubes 5 in the heat exchange structure at the second end, one end thereof does not share a steam drum with other heat exchange structures, that is, there is a steam drum that is only connected to one end of the heat exchange tube 5 in the heat exchange structure at the second end, and the steam drum is connected to the other of the second low-temperature medium inlet 102 and the second normal-temperature medium outlet 104. In this way, the heat exchange structures and the steam drums located in the upper steam drum cavity and the lower steam drum cavity are connected in series in sequence to form an S-shaped second serpentine flow channel, for example Figure 4 The flow direction of the low-temperature medium corresponding to the middle dotted line is the second serpentine flow channel.

[0046] In this embodiment, the heat exchange tube 5 is a clean porous tube made of stainless steel or copper, and a plurality of fins 501 are arranged on the outer wall of the heat exchange tube 5 at intervals along the circumference. The fins 501 are made of aluminum alloy, stainless steel or copper to improve the heat exchange efficiency of the heat exchange structure. Preferably, in the same heat exchange structure, some of the fins 501 on two adjacent heat exchange tubes 5 are fixedly connected by a stabilizing bracket 502, for example Figure 5 As shown, the structural strength of the heat exchange structure is effectively improved.

[0047] In this embodiment, the diameters of the heat exchange tubes 5 in the same heat exchange structure are the same. As a preferred embodiment, in the direction from the first end of the second serpentine flow channel to the second end of the second serpentine flow channel, the diameters of the heat exchange tubes 5 in each heat exchange structure increase successively, for example Figure 6As shown, as the cryogenic medium changes from liquid to supercritical state and then to gas during the flow process, the pressure and temperature of the cryogenic medium change synchronously during this process. At the same time, the diameter of the heat exchange tube 5 increases as the cryogenic medium flows toward the assembly, and the number of heat exchange tubes 5 also increases accordingly, so that the flow area of ​​the cryogenic medium in the heat exchange structure matches the cryogenic medium after the pressure and temperature change in real time, thereby reducing thermal resistance and improving heat exchange efficiency. As for the specific number of heat exchange tubes 5, the shape, type, and number of fins 501 on the heat exchange tubes 5 can be selected and adjusted according to the actual heat exchange amount.

[0048] In this embodiment, water vapor at 373-500K generated by combustion of the gas generator 7 is used as a heat exchange medium, and the steam sensible heat, evaporation latent heat and liquid sensible heat of the high-temperature medium are utilized to reduce the steam flow rate, thereby achieving long-term steady-state supply of the gas supply system. At the same time, excessive water vapor temperature is prevented from damaging the heat exchange pipeline during the heat exchange process, thereby ensuring long-term steady-state operation of the gas supply system.

[0049] refer to Figure 7 The gas generator 7 includes a fuel inlet 701, a water inlet 702, an oxidant inlet 703, an injector 704, a combustion chamber 705, a Laval nozzle 706, a cooling chamber 707, a cooling water inlet 708 and a water vapor outlet 709. The fuel, water and oxidant enter the gas generator 7 through the fuel inlet 701, the water inlet 702 and the oxidant inlet 703 respectively, and then are mixed and burned in the combustion chamber 705 to generate a gas with a temperature of 800K~2000K and a pressure of 2MPa~3MPa. The gas is injected through the Laval nozzle 706 in the cooling chamber 707 through the cooling water inlet 708 to generate a low-temperature water vapor with a temperature of 373K~500K and a pressure of ≤0.5MPa, and finally discharged from the water vapor outlet 709, thereby entering the first serpentine flow channel through the first high-temperature medium inlet 101.

[0050] In addition, although the shell 1 and the steam drum 6 in the figures of the present embodiment are both in the shape of a cubic structure, in a specific application, the shapes of the shell 1 and the steam drum 6 can be adaptively adjusted according to actual needs or limitations.

[0051] The above description is only a preferred embodiment of the present invention, and does not limit the protection scope of the present invention. All equivalent structural changes made by using the contents of the present invention specification and drawings under the inventive concept of the present invention, or directly / indirectly applied in other related technical fields are included in the protection scope of the present invention.

Claims

1. A large flow rate low temperature medium real-time vaporization system, characterized in that: The invention comprises a hollow shell, wherein a first serpentine flow channel and a second serpentine flow channel which are not connected to each other are arranged in the shell, and a heat exchange structure is arranged between the first serpentine flow channel and the second serpentine flow channel, wherein the heat exchange structure comprises a plurality of heat exchange tubes which are parallel to each other and are distributed in a linear array or a rectangular array; The shell is provided with a first high-temperature medium inlet, a first normal-temperature medium outlet, a second low-temperature medium inlet and a second normal-temperature medium outlet; The first high-temperature medium inlet is connected to the first end of the first serpentine flow channel, and the first normal-temperature medium outlet is connected to the second end of the first serpentine flow channel; The second low-temperature medium inlet is connected to the first end of the second serpentine flow channel, and the second normal-temperature medium outlet is connected to the second end of the second serpentine flow channel; The first high-temperature medium inlet and the second normal-temperature medium outlet are located at a first end of the shell, and the second low-temperature medium inlet and the first normal-temperature medium outlet are located at a second end of the shell; Two first partitions are provided in the shell to divide the internal space of the shell into an upper steam drum cavity, a heat exchange cavity and a lower steam drum cavity; A plurality of staggered baffles are provided in the heat exchange cavity to divide the heat exchange cavity to form the first serpentine flow channel; There are multiple heat exchange structures, and each of the heat exchange structures is sequentially arranged in the heat exchange cavity, each of the heat exchange structures includes a plurality of heat exchange tubes that are parallel to each other and distributed in a linear array or a rectangular array, and both ends of each heat exchange tube are respectively connected to the two first partitions; A second partition is provided in the upper steam drum cavity and the lower steam drum cavity to divide the upper steam drum cavity and the lower steam drum cavity into a plurality of steam drums; The same end of all the heat exchange tubes in two adjacent heat exchange structures is connected to the same steam drum, so that the heat exchange tubes cooperate with each steam drum to form the second serpentine flow channel.

2. The large flow rate low temperature medium real-time vaporization system according to claim 1 is characterized in that: A plurality of fins are arranged on the outer wall of the heat exchange tube at intervals along the circumferential direction.

3. The large flow rate low temperature medium real-time vaporization system according to claim 2 is characterized in that: In the same heat exchange structure, some of the fins on two adjacent heat exchange tubes are fixedly connected by a stabilizing bracket.

4. The large flow rate low temperature medium real-time vaporization system according to any one of claims 1 to 3, characterized in that: In the same heat exchange structure, the diameters of the heat exchange tubes are the same; In the direction from the first end of the second serpentine flow channel to the second end of the second serpentine flow channel, the diameters of the heat exchange tubes in each of the heat exchange structures increase sequentially.

5. The large flow rate cryogenic medium real-time vaporization system according to any one of claims 1 to 3, characterized in that: Ribs or ribs are provided inside the steam drum to enhance the strength of the high-pressure structure.

6. The large flow rate low temperature medium real-time vaporization system according to any one of claims 2 to 3, characterized in that: The heat exchange tube is made of stainless steel or copper, and the fin is made of stainless steel or aluminum or copper.

7. The large flow rate low temperature medium real-time vaporization system according to any one of claims 1 to 3, characterized in that: It also includes a gas generator, wherein the first high-temperature medium inlet is in communication with the gas generator; The gas generator first uses alcohol or kerosene or methane or isobutane, liquid / gas oxygen or air, and water to burn to generate gas with a temperature of 800K~2000K and a pressure of 2MPa~3MPa, and then adds water to mix and evaporate into low-temperature water vapor with a temperature of 373K~500K and a pressure of ≤0.5MPa.

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