Surface pit heat exchange unit
By setting up a hemispherical pit and convex hull on the shell of a sphere or sphere-like heat exchange unit, the problems of high maintenance costs and low efficiency of traditional heat exchange equipment are solved, the heat exchange efficiency and mechanical strength are improved, and more efficient Heat transfer and dust removal.
Patent Information
- Application Number
- CN202420862777.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-04-24
- Publication Date
- 2024-12-10
- Estimated Expiration
- 2034-04-24
AI Technical Summary
In the existing heat storage and exchange technologies, traditional tube, plate or filler-type heat exchange equipment needs to be shut down during maintenance and replacement, which increases maintenance costs, and the heat exchange area of the sphere or sphere-like heat exchange unit is small. It has low efficiency, is easily damaged due to physical changes, and is prone to accumulation of dust to affect efficiency.
Design a surface pit heat exchange unit, with a hemispherical pit and corresponding convex hull on the outer shell of the sphere or sphere-like body. The cross-section of the pit is arcuate or semicircular, accounting for 30%-90% of the surface area of the shell, and the internal filling phase change is Materials, the shell material is ordinary carbon steel, stainless steel, etc., and the inner ribs or fins are added to enhance strength.
The heat exchange area is increased through the pit and convex hull structure, the heat exchange efficiency and mechanical strength are improved, the thermal stress resistance and pressure bearing capacity are resisted, the surface dust is removed, and the service life of the heat exchange unit is extended.
Smart Images
Figure CN222143875U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of heat exchange equipment, in particular to a surface pit heat exchange unit. Background Art
[0002] In the existing heat storage and heat exchange technology, the heat storage and heat exchange are generally carried out in the form of media such as tubes, plates or fillers. For example, in the boiler system, the air preheater is a heat exchange device. The flue gas and air after the fuel combustion flow inside and outside the heat exchange tube or heat exchange plate respectively to realize the heat transfer. However, in the actual application of this traditional heat exchange technology, because the heat exchange tube or heat exchange plate is fixedly installed on the heat exchange device, it cannot be repaired or replaced during the operation of the whole machine (such as the boiler), so the whole machine needs to be shut down for repair and replacement, which further increases the maintenance cost of the equipment. The heat exchange filler in the form of filler is usually composed of quartz sand, alumina particles, iron oxide particles, inert ash and other particles. The pores are small, the heat exchange is uneven, and the heat exchange is difficult to accurately control, resulting in a waste of heat resources. To solve the above technical problems. The existing solution is to set up two heat exchange spaces and introduce high-temperature medium and low-temperature medium respectively; the heat exchange unit of the heat storage and heat exchange medium is a sphere or a spherical body, which circulates in the two heat exchange spaces to realize heat transfer. In this solution, the high-temperature medium and the low-temperature medium flow in their respective heat exchange spaces, and the heat exchange unit flows between the two heat exchange spaces. When the heat exchange unit is damaged, the heat exchange unit can be taken out at any time; and it is convenient to increase the number of heat exchange units in the heat exchange space.
[0003] At present, the method of using spherical or spherical heat exchange units to circulate in the heat exchange space for storage and heat exchange still has the following shortcomings. The heat exchange medium often carries impurities such as dust. For example, in a boiler system, the heat exchange medium is flue gas. The flue gas after the fuel combustion carries fly ash particles, which can easily cause dust accumulation and scaling on the surface of the heat exchange unit, affecting the heat exchange efficiency of the heat exchange unit. In severe cases, it needs to be cleaned, which increases maintenance costs. Under the same volume, the area of the sphere is the smallest, so the heat exchange area of the heat exchange unit is small, the time required for heat exchange is longer, and the heat exchange efficiency is low; the heat exchange unit is filled with heat storage medium, and a physical state change will occur under high or low temperature environment, such as liquid to gas state. In this process, the heat exchange unit needs to withstand greater pressure and is prone to damage. Utility Model Content
[0004] In order to solve the problems existing in the above-mentioned prior art, the utility model provides a surface pit heat exchange unit to solve the current technical problems.
[0005] The technical solution adopted by the utility model to solve its technical problems is:
[0006] The utility model provides a surface pit heat exchange unit, comprising: an outer shell, the outer shell is a spherical or spherical-like outer shell, and a plurality of pits are arranged on the surface of the outer shell.
[0007] Preferably, the pit is a hemispherical pit, the pit is arranged on the outer surface of the shell, the inner surface of the shell forms a hemispherical convex hull corresponding to the pit, and the cross-section of the pit is arcuate or semicircular.
[0008] Preferably, the shell is filled with phase change material.
[0009] Preferably, the total surface area of all the pits is 30%-90% of the surface area of the outer shell, and the diameter of the outer shell is not less than 30 mm.
[0010] Preferably, the ratio of the length d of the pit cross section to the shell ball diameter R is between 0.01:1 and 0.4:1.
[0011] Preferably, the inner wall and / or outer wall of the shell is coated with a layer of anti-corrosion coating.
[0012] Preferably, the shell material includes but is not limited to ordinary carbon steel, stainless steel, polytetrafluoroethylene, POK polyketone, and PPS alloy.
[0013] Preferably, inner ribs or fins are provided on the inner surface of the outer shell for enhancing the strength of the outer shell.
[0014] Preferably, the pit is an elliptical pit or a conical pit.
[0015] Preferably, the outer shell is also provided with one or more of the following features: holes, convex humps, inner ribs and fins.
[0016] The beneficial effects of the utility model are:
[0017] The pits are set on the surface of the heat exchange unit. The vortex generated by the fluid passing through the vortex pits not only strengthens the convective heat transfer, but also carries away some tiny particles near the vortex pits, so that it has the function of removing dust on the surface of the heat exchange unit.
[0018] The outer surface of the heat exchange unit is provided with pits, and the inner surface has convex hulls generated by squeezing the pits, which significantly increases the heat exchange area of the heat exchange unit and effectively improves the heat exchange efficiency.
[0019] Pits are set on the surface of the heat exchange unit to destroy the boundary layer between the fluid and the surface, causing the fluid to generate eddy currents. The eddy currents are formed and gradually expand to form a vortex. The vortex increases the mixing and disturbance of the fluid close to the surface, and due to the delay of the separation point of the thin layer of flow between the fluid and the surface, the enhancement of the convective heat transfer is more obvious, which greatly improves the heat transfer coefficient of the heat exchange unit.
[0020] The heat exchange unit is equipped with features such as pits, convex humps, and internal ribs, which changes the structural shape of the heat exchange unit and improves the overall mechanical strength. At the same time, the heat exchange unit's resistance to thermal stress and pressure bearing capacity are also improved. BRIEF DESCRIPTION OF THE DRAWINGS
[0021] The above aspects and advantages of the present invention will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which:
[0022] Figure 1 It is a structural schematic diagram of a surface pit heat exchange unit according to an embodiment of the utility model;
[0023] Figure 2 It is a schematic structural diagram of a shell with convex humps of a surface pit heat exchange unit according to an embodiment of the utility model;
[0024] Figure 3 It is a schematic diagram of the cross-sectional structure of the elliptical pit of the surface pit heat exchange unit of the embodiment of the utility model;
[0025] Figure 4 It is a schematic diagram of the cross-sectional structure of the hemispherical pits of the surface pit heat exchange unit of the embodiment of the utility model;
[0026] Figure 5 It is a structural schematic diagram of a shell with inner ribs of a surface pit heat exchange unit according to an embodiment of the utility model;
[0027] Figure 6 It is a schematic cross-sectional structural diagram of a shell with inner ribs and fins of a surface pit heat exchange unit of an embodiment of the utility model;
[0028] Figure 7 It is a schematic structural diagram of a shell with inner ribs and fins of a surface pit heat exchange unit according to an embodiment of the utility model;
[0029] Figure 8 It is a schematic cross-sectional structural diagram of a shell with grooves and holes of a surface pit heat exchange unit of an embodiment of the utility model;
[0030] Fig. 9 It is a schematic structural diagram of a shell with grooves and holes of a surface pit heat exchange unit according to an embodiment of the utility model.
[0031] Description of Reference Numerals
[0032] exist Figure 1-Figure 9 Middle, inner rib 1. DETAILED DESCRIPTION
[0033] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.
[0034] A surface pit heat exchange unit, the structure of which includes: the heat exchange unit is spherical or spherical, the shell is made of ordinary carbon steel, and other materials with certain corrosion resistance can also be selected, such as ordinary carbon steel, stainless steel, polytetrafluoroethylene, POK polyketone, PPS alloy, etc. The diameter of the heat exchange unit is not less than 30mm, and the shell is filled with phase change material. In the phase change process of the phase change material, the substance changes from one phase to another, such as solid to liquid or liquid to gas.
[0035] The outer surface of the sphere or spheroid shell of the heat exchange unit is provided with a plurality of hemispherical pits, the sizes of the hemispherical pits are basically the same, and the cross-section is arcuate or semicircular. Correspondingly, the inner surface of the sphere or spheroid shell is formed with a hemispherical convex hull formed by extrusion processing of the hemispherical pits to ensure the uniformity of the shell thickness. The hemispherical pits are basically evenly arranged on the outer surface of the shell, accounting for 30%-90% of the surface area of the outer surface of the shell; the ratio of the depth h of the hemispherical pits to the ball diameter R of the heat exchange unit is 0.01 to 0.2, and the ratio of the cross-sectional length d of the hemispherical pits to the ball diameter R of the heat exchange unit is 0.01 to 0.4. The purpose of setting the dimples on the outer surface of the heat exchange unit is to imitate the drag reduction principle of golf balls. When the fluid flows through, the dimples exert disturbance on it. The fluid generates many small vortices due to the dimples on the surface of the heat exchange unit, so that the thin layer of fluid close to the surface (the surface of the heat exchange unit) changes from laminar flow to turbulent flow. The kinetic energy of turbulence is greater, so the fluid has greater kinetic energy to propagate backwards, the inertial force is stronger, and the effect of removing dust on the surface of the heat exchange unit is better.
[0036] Optimally, the shell material of the heat exchange unit can be made of PPS alloy (polyphenylene sulfide alloy). PPS is a special engineering plastic with excellent physical and chemical properties. It has excellent performance in terms of high mechanical strength, high temperature resistance, high flame retardancy, corrosion resistance, high hardness, and thermal stability. PPS alloy is made by blending or compounding with other polymers or fillers, while retaining the original performance and improving its toughness and wear resistance.
[0037] Optimized, the composition of the heat exchange medium and phase change material may cause corrosion to the heat exchange unit. In order to prevent corrosion, anti-corrosion coatings can be applied to the inner and / or outer walls of the heat exchange unit. For example, spraying corrosion-resistant silicone coatings, spraying rare earth alloys, and brushing epoxy glass coatings.
[0038] Optimally, in addition to filling the phase change material inside the heat exchange unit shell, other heat storage materials may also be selected to be filled, such as heat transfer oil, sand, gravel, inert ash and other materials; or it may be selected not to fill the heat storage medium and directly use the heat exchange unit shell for heat exchange.
[0039] Optimally, internal ribs 1, fins and other structures can be arranged on the inner surface of the shell to improve the heat exchange efficiency and make the material filled inside the heat exchange unit heated more evenly. The materials of the internal ribs 1, fins and other structures need to have good thermal conductivity.
[0040] Preferably, inner ribs 1 may be provided inside the outer shell to enhance the strength of the heat exchange unit.
[0041] Optimally, the size and shape of the hemispherical pit of the heat exchange unit can be consistent or inconsistent, but still occupy at least 30% of the surface area of the outer surface of the shell. The hemispherical pit can also be replaced by a pit or groove of other shapes, such as an elliptical or conical shape, or the contour or cross-section of the pit presents other regular or irregular shapes.
[0042] Optimally, the surface features of the heat exchange unit may not only include one type of pit, but also may include holes, convex humps, inner ribs 1, wings and other features at appropriate locations of the heat exchange unit.
[0043] The pits are set on the surface of the heat exchange unit. The vortex generated by the fluid passing through the vortex pits not only strengthens the convective heat transfer, but also carries away some tiny particles near the vortex pits, so that it has the function of removing dust on the surface of the heat exchange unit.
[0044] The outer surface of the heat exchange unit is provided with pits, and the inner surface has convex hulls generated by squeezing the pits, which significantly increases the heat exchange area of the heat exchange unit and effectively improves the heat exchange efficiency.
[0045] Pits are set on the surface of the heat exchange unit to destroy the boundary layer between the fluid and the surface, causing the fluid to generate eddy currents. The eddy currents are formed and gradually expand to form a vortex. The vortex increases the mixing and disturbance of the fluid close to the surface, and due to the delay of the separation point of the thin layer of flow between the fluid and the surface, the enhancement of the convective heat transfer is more obvious, which greatly improves the heat transfer coefficient of the heat exchange unit.
[0046] The heat exchange unit is equipped with pits, convex bumps, ribs and other features, which changes the structural shape of the heat exchange unit and improves the overall mechanical strength. At the same time, the heat exchange unit's resistance to thermal stress and pressure bearing capacity are also improved.
[0047] Finally, it should be noted that the above is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art can still modify the technical solutions described in the aforementioned embodiments or make equivalent substitutions for some of the technical features therein. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.
Claims
1. A surface pit heat exchange unit, comprising: The shell is characterized in that: the shell is a spherical or spherical shell, and a plurality of pits are arranged on the surface of the shell.
2. The surface pit heat exchange unit according to claim 1, characterized in that: The pit is a hemispherical pit, which is arranged on the outer surface of the shell, and the inner surface of the shell forms a hemispherical convex hull corresponding to the pit, and the cross section of the pit is arcuate or semicircular.
3. The surface pit heat exchange unit according to claim 1, characterized in that: The shell is filled with phase change material.
4. The surface pit heat exchange unit according to claim 1, characterized in that: The total surface area of all the pits is 30%-90% of the surface area of the shell, and the diameter of the shell is not less than 30mm.
5. The surface pit heat exchange unit according to claim 1, characterized in that: The ratio of the length d of the pit cross section to the shell ball diameter R is between 0.01:1 and 0.4:
1.
6. The surface pit heat exchange unit according to claim 1, characterized in that: The inner wall and / or outer wall of the shell is coated with a layer of anti-corrosion paint.
7. The surface pit heat exchange unit according to claim 1, characterized in that: The shell material includes but is not limited to ordinary carbon steel, stainless steel, polytetrafluoroethylene, POK polyketone, and PPS alloy.
8. The surface pit heat exchange unit according to claim 1, characterized in that: The inner surface of the shell is provided with inner ribs or fins for enhancing the strength of the shell.
9. The surface pit heat exchange unit according to claim 1, characterized in that: The pit is an elliptical pit or a conical pit.
10. The surface pit heat exchange unit according to claim 1, characterized in that: The shell is also provided with one or more of the following features: holes, convex humps, inner ribs, and fins.