A spherical high temperature heat accumulator

Abstract

The present invention discloses a spherical high-temperature heat accumulator, comprising a metal spherical shell and an internal heat storage material, wherein the metal spherical shell is composed of two parts, an upper part and an lower part, and is made of high-temperature resistant and corrosion-resistant stainless steel. The two parts are an upper cover and a lower container, which are connected and sealed by vacuum nickel brazing technology. The internal heat storage material is a high-temperature alloy phase change material or a high-temperature molten salt. The spherical high-temperature heat accumulator of the present invention has good pressure-bearing characteristics, a simple structure and easy processing, and is suitable for high-pressure application scenarios with heat storage requirements. In addition, the heat accumulator can meet the high-temperature heat storage requirements in the temperature range of 500-800°C by filling heat storage materials with corresponding characteristics, and has a wide range of applications.

Description

Technical Field

[0001] The present invention relates to the field of heat storage, and in particular to a metal spherical heat storage structure with heat storage material filled inside, which is suitable for heat storage application scenarios with high temperature and high pressure characteristics. Background Art

[0002] There is often a mismatch between energy supply and demand. Thermal storage technology can collect and store excess heat and then release it at the appropriate time, which is an important means to solve this problem. High-temperature phase change thermal storage materials have the advantage of a high melting point, which can increase the total heat storage capacity. High-temperature phase change thermal storage materials are mainly composed of some molten salts, metals and alloys. Molten salts have a series of advantages such as a wide operating temperature range, high heat transfer performance, low working pressure and low price. Although the heat storage density of metal alloys is relatively low compared to molten salts, their thermal conductivity is much higher than that of other phase change materials, even up to dozens of times, and the stability of metals is very good, which has great application potential.

[0003] During the use of high-temperature phase-change thermal storage materials, packaging technology is required to prevent them from corroding the container and melting and leaking. However, the more mature technical solution currently is to use high-density polyvinyl chloride packaging, which is suitable for the field of low-temperature thermal storage. During the phase change process of high-temperature phase-change thermal storage materials, there is a volume change and large thermal stress, so the requirements for packaging materials and packaging structures are more stringent.

[0004] Therefore, there is an urgent need to develop a high-temperature heat accumulator with better pressure-bearing characteristics. Summary of the invention

[0005] The purpose of the present invention is to provide a spherical high-temperature heat accumulator suitable for high-pressure application scenarios in view of the shortcomings of the prior art. The heat accumulator has a simple structure and is easy to process. It can meet the high-temperature heat storage requirements of different temperature ranges by filling heat storage materials with corresponding characteristics, and has a wide range of applications.

[0006] To achieve the above-mentioned purpose, the technical solution provided by the present invention is as follows: The present invention proposes a spherical high-temperature heat accumulator, including a metal spherical shell and a heat storage material, wherein the metal spherical shell is composed of a shell cover and a shell container fixedly connected thereto; the heat storage material is placed in the metal spherical shell.

[0007] Furthermore, the heat storage material is a high-temperature alloy phase change material or a high-temperature molten salt, which meets the high-temperature heat storage demand of 500-800°C; the volume of the heat storage material after melting is smaller than the volume of the shell container.

[0008] Furthermore, the high temperature alloy phase change material is a magnesium-aluminum alloy, an aluminum-copper alloy or a magnesium-zinc-copper alloy.

[0009] Furthermore, the high temperature molten salt is NaCl(47)-MgCl(53), NaCl(50)-MgCl2(50)LiF(67)-MgF2(33), LiF(67)-NaF(44)-MgF2(10).

[0010] Furthermore, the shell cover is provided with a shell cover protrusion, and the shell container is provided with a shell container groove; the shell cover protrusion and the shell container groove are fixedly connected and sealed by vacuum brazing.

[0011] Furthermore, a plurality of through holes are formed on the housing cover protrusion.

[0012] Furthermore, the housing cover protrusion preferably has two symmetrical through holes.

[0013] Furthermore, the through hole is a triangle with two bases no greater than 0.5 mm and a height no greater than 0.25 mm.

[0014] Furthermore, the metal spherical shell is made of stainless steel.

[0015] Furthermore, the shell cover and the shell container are respectively provided with a plane on the top and bottom surfaces thereof.

[0016] The present invention has at least the following beneficial technical effects:

[0017] (1) The heat storage device of the present invention is a spherical structure, has good pressure-bearing characteristics, is easy to stack, has a simple structure and is easy to process, and is suitable for application scenarios with heat storage requirements.

[0018] (2) The shell cover and shell container in the heat accumulator of the present invention are respectively provided with a plane on the top and bottom surfaces. This micro plane is convenient for clamping in the vacuum brazing machine. Stable clamping can ensure the brazing quality. At the same time, processing with a micro plane has the advantages of not losing balls and being easy to stack.

[0019] (3) A through hole is opened on the convex part of the shell cover, so that a through hole is reserved on the sealing surface to allow the gas to escape fully during vacuuming. Otherwise, after the lead solder melts at high temperature, the internal gas escapes, which will lead to uneven brazing and even leakage. The through hole shape is preferably triangular, which can achieve the exhaust effect while better ensuring that it can be sealed after the solder melts.

[0020] (4) The heat storage device of the present invention can be loaded with heat storage materials with corresponding characteristics, such as high-temperature alloy phase change materials such as magnesium-aluminum alloy, aluminum-copper alloy, magnesium-zinc-copper alloy, and high-temperature molten salts such as NaCl(47)-MgCl(53), NaCl(50)-MgCl2(50)LiF(67)-MgF2(33), LiF(67)-NaF(44)-MgF2(10), so as to meet the high-temperature heat storage requirements in the temperature range of 500-800°C, and has a wide range of applications.

[0021] (5) The volume of the heat storage material after melting is smaller than the volume of the shell container, so that the heat storage material will not escape from the brazing seam after melting, thereby destroying the brazing effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 This is a schematic diagram of the appearance of an embodiment of the present invention;

[0023] Figure 2 A cross-sectional structural diagram of an embodiment of the present invention;

[0024] Figure 3 The schematic diagram of the structure of the upper half of the metal shell cover according to an embodiment of the present invention; (a) is a side view, and (b) is a bottom view;

[0025] Figure 4 This is a schematic diagram of the structure of the lower half container of the metal shell according to an embodiment of the present invention; (a) is a side view, and (b) is a top view;

[0026] Figure 5 The schematic diagram of the shell connection structure of an embodiment of the present invention; (a) is a diagram of a region without a triangular opening, and (b) is a diagram of a region with a triangular opening.

[0027] In the figure: 1-metal spherical shell; 2-shell cover; 3-shell container; 4-heat storage material; 5-triangular opening; 6-nickel-based solder; 21-shell cover plane; 22-shell cover protrusion; 31-shell container plane; 32-shell container groove. DETAILED DESCRIPTION

[0028] Exemplary embodiments will be described in detail herein, examples of which are shown in the accompanying drawings. When the following description refers to the drawings, the same numbers in different drawings represent the same or similar elements unless otherwise indicated. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with the present invention. Instead, they are merely examples of devices and methods consistent with some aspects of the present invention as detailed in the appended claims.

[0029] The terms used in the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention. The singular forms "a", "the" and "the" used in the present invention and the appended claims are also intended to include plural forms unless the context clearly indicates other meanings. It should also be understood that the term "and / or" used herein refers to and includes any or all possible combinations of one or more associated listed items.

[0030] The present invention will be further described below in conjunction with the accompanying drawings and implementation examples. It should be noted that the specific embodiments described herein are only used to explain the relevant inventions, and the protection scope of the present invention is not limited to the embodiments. In the absence of conflict, the features in the following embodiments and implementations can be combined with each other.

[0031] like Figure 1 and Figure 2 As shown, a spherical high-temperature heat accumulator provided by the present invention mainly comprises a metal spherical shell 1 and an internal heat storage material 4, wherein the metal spherical shell 1 is composed of an upper shell cover 2 and a lower shell container 3. The heat accumulator of the present invention is a spherical structure, has good pressure bearing characteristics, is easy to stack, has a simple structure and is easy to process, and is suitable for application scenarios with heat storage requirements.

[0032] like Figures 1 to 5 As shown, the metal spherical shell 1 is made of 310s stainless steel which is resistant to high temperature and corrosion and has high thermal conductivity.

[0033] like Figures 1 to 4 As shown, the upper shell cover 2 and the lower shell container 3 are provided with a shell cover plane 21 and a shell container plane 31 on the top and bottom surfaces, respectively, so as to facilitate the clamping, fixing and alignment of the two hemispheres by the clamp during the processing. This micro plane is convenient for the clamp in the vacuum brazing machine to hold, and the brazing quality can be guaranteed by stable clamping. At the same time, the processing has the advantages of micro plane without losing the ball and easy accumulation.

[0034] like Figures 2 to 5 As shown, the upper shell cover 2 and the lower shell container 3 are sealed by vacuum end face brazing, and the joints are respectively a circle of annular shell cover protrusions 22 and a circle of annular shell container grooves 32, with nickel-based brazing material 6 in the middle.

[0035] like Figure 2As shown, the internal heat storage material 4 is a high-temperature alloy phase change material (such as magnesium-aluminum alloy, aluminum-copper alloy, magnesium-zinc-copper alloy, etc.) or a high-temperature molten salt (such as NaCl(47)-MgCl2(53) and NaCl(50)-MgCl2(50) with a phase change point of 450°C, LiF(67)-MgF2(33) with a phase change point of 746°C, LiF(67)-NaF(44)-MgF2(10) with a phase change point of 632°C, etc.), which meets the high-temperature heat storage requirements of 500-800°C. The filling amount is controlled so that its volume after melting is smaller than the volume of the container in the lower half of the shell, so that it will not escape from the brazing seam after melting, thereby destroying the brazing effect. In the embodiment of the present invention, the heat storage material 4 with the corresponding phase change point can be selected according to the requirements of the high-temperature heat storage temperature.

[0036] like Figure 3 and 5 As shown, the housing cover protrusion 22 may be provided with a plurality of through holes, so that through holes are reserved on the sealing surface so that the gas can fully escape when the vacuum is drawn, otherwise after the lead solder melts at high temperature, the internal gas escapes, which will cause uneven soldering.

[0037] In the embodiment of the present invention, two triangular openings 5 ​​with a base not greater than 0.5 mm and a height not greater than 0.25 mm are symmetrically opened on the annular shell cover protrusion 22 of the upper hemisphere of the metal spherical shell, so that the gas in the cavity of the ball can be discharged during the vacuuming process and the through hole can be blocked after the solder melts.

[0038] During the entire processing process, firstly, the corresponding heat storage material 4 is filled in the lower shell container 3 of the metal spherical shell 1, and then the upper shell cover 2 and the lower shell container 3 of the metal spherical shell 1 are combined, and the nickel-based brazing material 6 is placed in the middle of the annular joint between the two, and then the upper and lower shell cover planes 21 and the shell container plane 31 of the metal spherical shell 1 are tightly attached with a clamp; they are fixed and clamped, and after vacuuming in a brazing furnace, they are brazed using vacuum end face nickel brazing technology, so that the heat storage material 4 is sealed in the metal spherical shell 1, and the production of the spherical high-temperature heat accumulator is completed.

[0039] The working process of the spherical high-temperature heat accumulator is as follows: after determining the specific number of spherical high-temperature heat accumulators to be used according to the heat storage demand, place them inside a sealed high-temperature and high-pressure device, turn on the heating device to store heat for them, and when the heating stops and the temperature around the heat accumulator drops, the heat accumulator will automatically release the stored heat.

[0040] The above description is only a preferred embodiment of the present application. The scope of the invention involved in the present application is not limited to the specific combination of the above-mentioned technical features. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the patent of the present invention should be included in the protection scope of the present invention.

Claims

1. A spherical high-temperature heat accumulator, characterized in that: It comprises a metal spherical shell (1) and a heat storage material (4), wherein the metal spherical shell (1) is composed of a shell cover (2) and a shell container (3) fixedly connected thereto; the heat storage material (4) is placed in the metal spherical shell (1); The heat storage material (4) is a high-temperature alloy phase change material or a high-temperature molten salt, which meets the high-temperature heat storage requirement of 500-800°C; The shell cover (2) is provided with a shell cover protrusion (22), and the shell container (3) is provided with a shell container groove (32); the shell cover protrusion (22) is provided with two symmetrical through holes, and the through holes are two triangles with a bottom side not greater than 0.5 mm and a height not greater than 0.25 mm; the bottom surface of the triangular opening passes through the bottom surface of the shell cover protrusion (22), and the two ends of the triangular opening pass through the shell cover protrusion (22); The housing cover protrusion (22) and the housing container groove (32) are fixedly connected and sealed by vacuum brazing.

2. The spherical high-temperature heat accumulator according to claim 1, characterized in that: The volume of the heat storage material (4) after melting is smaller than the volume of the shell container (3).

3. The spherical high-temperature heat accumulator according to claim 1, characterized in that: The high temperature alloy phase change material is a magnesium-aluminum alloy, an aluminum-copper alloy or a magnesium-zinc-copper alloy.

4. The spherical high-temperature heat accumulator according to claim 1, characterized in that: The high temperature molten salt is one of 47wt% NaCl and 53wt% MgCl2, 50wt% NaCl and 50wt% MgCl2, 67wt% LiF and 33wt% MgF2.

5. The spherical high-temperature heat accumulator according to claim 1, characterized in that: The metal spherical shell (1) is made of stainless steel.

6. The spherical high-temperature heat accumulator according to claim 1, characterized in that: A shell cover plane (21) is provided at the top of the shell cover (2), and a shell container plane (31) is provided at the bottom of the shell container (3).

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