Magnetic assisted porous fin heat exchanger and real-time heat exchange control method
By using magnetically sensitive metamaterials in heat exchanger fins to adjust the pore size under the action of magnetic field, the problem of poor heat exchange efficiency caused by the fixation of pore size in the prior art is solved, and efficient exchange at different fluid inlet speeds is achieved Thermal performance.
Patent Information
- Application Number
- CN202010635137.X
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- Filing Date
- 2020-07-03
- Publication Date
- 2024-12-31
- Estimated Expiration
- 2040-07-03
AI Technical Summary
The size of the holes in the fins of existing heat exchangers is fixed, making it difficult to adjust in real time at different fluid inlet velocities, resulting in poor heat exchange efficiency.
Magnetic sensitive metamaterials are used to change the pore size under the action of magnetic field, real-time adjustment of fin pores is achieved through flow velocity detection and magnetic field control, and combined with CAE simulation analysis to optimize the pore size.
The highest heat exchange performance is achieved at different fluid inlet velocities, promoting lateral mixing between the fluids, and improving the overall heat exchange performance of the heat exchanger.
Smart Images
Figure CN111637771B_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to a porous fin heat exchanger and a control method thereof in the field of engineering heat exchange technology, and in particular to a magnetically assisted porous fin heat exchanger and a method for controlling heat exchange in real time. Background Art
[0002] With the rapid development of metallurgy and chemical (petrochemical) industries, the demand for air separation equipment is increasing. Heat exchangers are key components in air separation equipment and are one of the key equipment for energy saving and consumption reduction in air separation equipment. Porous fins have the characteristics of simple processing technology and large specific surface area. They not only reduce the weight of the fins, but also enhance the heat transfer performance of the fins. They are widely used in various heat exchangers and have always been the focus of research by scholars at home and abroad. The openings in the fins can continuously break the thermal boundary layer, increase the disturbance of the airflow, thereby improving its heat transfer performance. At the same time, they can also promote lateral mixing between fluids, which is beneficial to the overall improvement of the heat exchange efficiency of the heat exchanger. The perforated fins are improved so that the improved perforated fins have a significant effect on improving the heat transfer performance of the heat exchanger. Summary of the invention
[0003] In view of the problems existing in the existing heat exchanger fins, the present invention provides a porous plate-fin heat exchanger whose pore size can be changed in real time, and a method for changing the pore size in real time to adjust and control the heat exchange working conditions and performance.
[0004] The technical solution of the present invention is as follows:
[0005] 1. A porous fin heat exchanger that can change pore size in real time:
[0006] The heat exchanger body is provided with eight heads, which are used as inlets and outlets of the fluid. Magnetic generating devices are installed on the symmetrical outer walls of the heat exchanger body, and multiple flow rate detection sensors are installed at the port of each head. The heat exchanger body has multiple layers of porous fin layers inside, and each layer of porous fin layers is composed of porous fins arranged at intervals and connected, and flow channels are formed between adjacent porous fins. The porous fins have circular holes, and magnetically sensitive metamaterials are installed in the circular holes. One side of the magnetically sensitive metamaterial is a fixed semicircle, and the other side is a deformable semi-ellipse. The semicircular side of the magnetically sensitive metamaterial is fixedly connected to one side of the circular hole of the porous fin by welding, and the semi-elliptical side is a free side that can be deformed between a semicircle and a semi-ellipse, and a gap is formed between the semi-elliptical side and the other side of the circular hole of the porous fin as a pore.
[0007] The base material of the magnetically sensitive metamaterial is CS25 condensed silicone rubber and CS25 condensed silicone rubber catalyst, and the inclusion is RED iron powder. The magnetically sensitive metamaterial can produce a stable deformation of the unit lattice structure inside it under the action of the magnetic field, thereby changing the deformation amount of the entire magnetically sensitive metamaterial and realizing the deformation of the free side between a semicircle and a semi-ellipse.
[0008] The thickness of the magnetically sensitive metamaterial in a natural state is consistent with the thickness of the porous fin.
[0009] The line connecting the magnetic generating devices on both sides of the heat exchanger body is the direction of the magnetic field, the flow channel direction between the porous fins is parallel to the direction of the magnetic field, and the semi-elliptical side deformation direction of the magnetically sensitive metamaterial is parallel to the direction of the magnetic field.
[0010] A plurality of flow rate detection sensors are evenly spaced around the head port along the circumferential direction.
[0011] The circular holes of the porous fins in the same porous fin layer have the same size, and the circular holes of the porous fins in different porous fin layers may be the same or different in size.
[0012] 2. A real-time control heat exchange method for a porous fin heat exchanger, the method comprising the following steps:
[0013] 1) CAE is used to conduct large-scale batch simulation analysis. Under the condition of n flows of different fluids inside the heat exchanger, i different fluid inlet velocities Vi of each flow are simulated to obtain the pore size of the porous fins in each porous fin layer at the optimal heat transfer efficiency. The pore size of each porous fin layer is classified and counted to obtain the mean Ei and variance Si of the pore size of each porous fin layer;
[0014] 2) preparing different layers of magnetosensitive metamaterials according to the mean Ei and variance Si of the pore sizes of the porous fins of different layers of porous fins, and installing them in the circular holes of the porous fins;
[0015] 3) When the porous fin heat exchanger is working, the flow velocity detection device evenly distributed at the inlet of the head detects the flow velocity of the fluid passing through, obtains the fluid inlet velocity Vi, and transmits it to the control device in real time; the cross-sectional deformation A of the magneto-sensitive metamaterial is obtained according to different fluid inlet velocities Vi, and then the magnetic field force Fi required to make the magneto-sensitive metamaterial undergo such cross-sectional deformation is obtained, and then the magnetic generating device is controlled to apply a uniform magnetic field force Fi, so as to change the deformation of the magneto-sensitive metamaterial in the porous fin in real time, and then change the size of the pores formed between the circular holes in different layers of the porous fin layer and the magneto-sensitive metamaterial;
[0016] 4) The change in the pore size of the porous fins of different porous fin layers regulates the heat exchange flow between adjacent porous fins, thereby changing the heat exchange efficiency and work of different porous fin layers, and realizing real-time control of heat exchange of the porous fin heat exchanger.
[0017] The initial cross-sectional size of the magneto-sensitive metamaterial in each layer is determined by the mean value Ei of the pore size of each porous fin layer. The larger the mean value Ei of the pore size is, the smaller the initial cross-sectional size of the magneto-sensitive metamaterial should be. The material ratio of the magnetic material to the non-magnetic material in the magneto-sensitive metamaterial in each layer is determined by the variance Si of the pore size of each layer. The larger the variance Si of the pore size is, the greater the deformation ability of the magneto-sensitive metamaterial should be.
[0018] The magnetically sensitive metamaterial in the porous fins of each porous fin layer has different magnetic magnitudes and deformation capabilities, so that different deformations can be achieved under the same magnetic field and different deformation magnitudes under the same magnetic field change, thereby controlling the heat exchange work.
[0019] The beneficial effects of the present invention are as follows:
[0020] 1) The present invention specially arranges magnetically sensitive metamaterials in the circular holes of the fins. Through the action of magnetic force, the porous fin heat exchanger can obtain different pore sizes under different head inlet flow rates, so that the heat exchanger can obtain the highest possible heat exchange performance under different inlet flow rates.
[0021] 2) The porous fin heat exchanger fins with magnetically sensitive metamaterials used in the present invention can destroy the boundary layer of the fluid, promote the lateral mixing between the fluids, and make the lateral mixing more uniform, thereby improving the overall heat exchange performance of the heat exchanger. BRIEF DESCRIPTION OF THE DRAWINGS
[0022] Figure 1 It is a schematic diagram of the structure appearance of the present invention;
[0023] Figure 2 It is a schematic diagram of the three-dimensional structure of a single-layer fin of the present invention;
[0024] Figure 3 It is a schematic diagram of the three-dimensional structure of a single fin of the present invention;
[0025] Figure 4 This is a flow chart of the method for controlling pore size of the present invention.
[0026] In the figure: a magnetic generating device 1, a sealing head 2, a flow velocity detecting device 3, a heat exchanger body 4, and a magnetically sensitive metamaterial 5. DETAILED DESCRIPTION
[0027] The technical solution of the present invention is further described below in conjunction with the accompanying drawings and specific embodiments. 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 should fall within the scope of protection of the present invention.
[0028] like Figure 1 As shown, the specific heat exchanger body 4 is provided with eight heads 2, and the heads 2 are used as the inlet and outlet of the fluid. The outer walls on both sides of the symmetrical sides of the heat exchanger body 4 are installed with magnetic generating devices 1. A plurality of flow velocity detection sensors are provided at the port of each head 2. The plurality of flow velocity detection sensors constitute a flow velocity detection device 3. The plurality of flow velocity detection sensors respectively detect the flow velocity of the fluid flowing through the head 2 and take the average as the final fluid velocity.
[0029] The heat exchanger body 4 has multiple layers of porous fins inside, such as Figure 2 As shown, each porous fin layer is composed of porous fins arranged at intervals and connected, and a flow channel is formed between adjacent porous fins. The porous fins have circular holes, and magnetically sensitive metamaterials are installed in the circular holes. One side of the magnetically sensitive metamaterial is a fixed semicircle, and the other side is a deformable semi-ellipse, as shown in FIG. Figure 3 As shown, the semicircular side of the magnetosensitive metamaterial is fixedly connected to one side of the circular hole of the porous fin by welding, and the semi-elliptical side is a free side that can be deformed between a semicircle and a semi-ellipse, forming a gap between the semi-elliptical side and the other side of the circular hole of the porous fin as a pore.
[0030] The specific implementation of the magnetically sensitive metamaterial has a base material of CS25 condensed silicone rubber and CS25 condensed silicone rubber catalyst, and an impurity of RED iron powder. The magnetically sensitive metamaterial can produce a stable deformation of its internal unit lattice structure under the action of a magnetic field, thereby changing the deformation of the entire magnetically sensitive metamaterial and achieving a deformation of the free side between a semicircle and a semi-ellipse.
[0031] In a specific implementation, the thickness of the magneto-sensitive metamaterial in a natural state is consistent with the thickness of the porous fin.
[0032] The line connecting the magnetic generating devices 1 on both sides of the heat exchanger body 4 is the direction of the magnetic field, the flow channel direction between the porous fins is parallel to the direction of the magnetic field, and the semi-elliptical side deformation direction of the magnetic sensitive metamaterial is parallel to the direction of the magnetic field.
[0033] A plurality of flow rate detection sensors are evenly spaced around the port of the head 2 along the circumferential direction.
[0034] The circular holes of the porous fins in the same porous fin layer have the same size, and the circular holes of the porous fins in different porous fin layers may be the same or different in size.
[0035] like Figure 4 As shown, the implementation process of the present invention includes:
[0036] 1) CAE is used to conduct large-scale batch simulation analysis. Under the condition of n flows of different fluids inside the heat exchanger, i different fluid inlet velocities Vi of each flow are simulated. Under the condition of designed inlet flow velocity distribution, the pore size of each porous fin layer at the optimal heat transfer efficiency is obtained. The pore size of each porous fin layer is classified and counted to obtain the mean Ei and variance Si of the pore size of each porous fin layer;
[0037] 2) preparing different layers of magnetosensitive metamaterials according to the mean Ei and variance Si of the pore sizes of the porous fins of different layers of porous fins, and installing them in the circular holes of the porous fins;
[0038] 3) When the porous fin heat exchanger is working, the flow velocity detection device 3 evenly distributed at the inlet of the head 2 detects the flow velocity of the fluid passing through, obtains the fluid inlet velocity Vi, and transmits it to the control device in real time;
[0039] According to the different fluid inlet velocities Vi, the cross-sectional deformation A of the magneto-sensitive metamaterial is obtained by processing the corresponding relationship, and then the magnetic field force Fi required to cause such a cross-sectional deformation of the magneto-sensitive metamaterial is obtained, and then the magnetic generating device 1 is controlled to apply a uniform magnetic field force Fi, so as to change the deformation of the magneto-sensitive metamaterial 5 in the porous fins in real time, and then change the size of the pores formed between the circular holes in different layers of the porous fins and the magneto-sensitive metamaterial 5; and this set of data is stored in the memory with the fluid inlet velocity Vi as a mark.
[0040] 4) The change in the pore size of the porous fins of different porous fin layers regulates the heat exchange flow between adjacent porous fins, thereby changing the heat exchange efficiency and work of different porous fin layers, and realizing real-time control of heat exchange of the porous fin heat exchanger.
[0041] The contents described in the present invention are only an enumeration of the implementation forms of the inventive concept. The protection scope of the present invention should not be regarded as limited to the specific forms described in the embodiments. Equivalent changes made according to the structure, shape and principle of the present invention should all be included in the protection scope of the present invention.
Claims
1. A porous fin heat exchanger capable of changing pore size in real time, characterized in that: The heat exchanger body (4) of the porous fin heat exchanger is provided with eight heads (2), the heads (2) are used as the inlet and outlet of the fluid, the outer walls of the heat exchanger body (4) on both symmetrical sides are provided with magnetic generating devices (1), and a plurality of flow rate detection sensors are provided at the port of each head (2); the heat exchanger body (4) has multiple layers of porous fin layers inside, each layer of the porous fin layers is composed of porous fins arranged at intervals and connected, and a flow channel is formed between adjacent porous fins, the porous fins have circular holes, and a magnetically sensitive metamaterial is installed in the circular hole, one side of the magnetically sensitive metamaterial is a fixed semicircle, and the other side is a deformable semi-ellipse, the semicircular side of the magnetically sensitive metamaterial is fixedly connected to one side of the circular hole of the porous fin by welding, the semi-elliptical side is a free side that can be deformed between a semicircle and a semi-ellipse, and a gap is formed between the semi-elliptical side and the other side of the circular hole of the porous fin as a pore.
2. A porous fin heat exchanger capable of changing pore size in real time according to claim 1, characterized in that: The base material of the magnetically sensitive metamaterial is CS25 condensing silicone rubber and CS25 condensing silicone rubber catalyst, and the impurity is RED type iron powder.
3. The porous fin heat exchanger capable of changing pore size in real time according to claim 1, characterized in that: The thickness of the magnetically sensitive metamaterial in a natural state is consistent with the thickness of the porous fin.
4. The porous fin heat exchanger capable of changing pore size in real time according to claim 1, characterized in that: The line connecting the magnetic generating devices (1) on both symmetrical sides of the heat exchanger body (4) is the direction of the magnetic field, the direction of the flow channel between the porous fins is parallel to the direction of the magnetic field, and the semi-elliptical side deformation direction of the magnetically sensitive metamaterial is parallel to the direction of the magnetic field.
5. The porous fin heat exchanger capable of changing pore size in real time according to claim 1, characterized in that: A plurality of flow rate detection sensors are evenly spaced in the circumferential direction around the port of the head (2).
6. The porous fin heat exchanger capable of changing pore size in real time according to claim 1, characterized in that: The circular holes of the porous fins in the same porous fin layer have the same size, and the circular holes of the porous fins in different porous fin layers may be the same or different in size.
7. A real-time control heat exchange method for a porous fin heat exchanger according to any one of claims 1 to 6, characterized in that: The method comprises the following steps: 1) CAE is used to conduct large-scale batch simulation analysis. Under the condition of n flows of different fluids inside the heat exchanger, i different fluid inlet velocities Vi of each flow are simulated to obtain the pore size of the porous fins in each porous fin layer at the optimal heat transfer efficiency. The pore size of each porous fin layer is classified and counted to obtain the mean Ei and variance Si of the pore size of each porous fin layer; 2) preparing different layers of magnetosensitive metamaterials according to the mean Ei and variance Si of the pore sizes of the porous fins of different layers of porous fins, and installing them in the circular holes of the porous fins; 3) When the porous fin heat exchanger is working, the flow velocity detection device (3) evenly distributed at the inlet of the head (2) detects the flow velocity of the fluid passing through, obtains the fluid inlet velocity Vi, and transmits it to the control device in real time; The cross-sectional deformation A of the magneto-sensitive metamaterial is obtained by processing according to different fluid inlet velocities Vi, and the magnetic field force Fi required to cause the magneto-sensitive metamaterial to undergo such cross-sectional deformation is obtained by processing, and then the magnetic generating device (1) is controlled to apply a uniform magnetic field force Fi, so as to change the deformation of the magneto-sensitive metamaterial (5) in the porous fin in real time, and then the size of the pores formed between the circular holes in different layers of the porous fin and the magneto-sensitive metamaterial (5) is changed; 4) The change in the pore size of the porous fins of different porous fin layers regulates the heat exchange flow between adjacent porous fins, thereby changing the heat exchange efficiency and work of different porous fin layers, and realizing real-time control of heat exchange of the porous fin heat exchanger.