Internal resistance control method, system, device and storage medium of plate heater

Abstract

The present invention discloses a method, system, computer equipment and storage medium for controlling the internal resistance of a plate heater. Based on the total flow rate of the fluid in the plate heater and the premise that the ratio of the fluid flow rate in each heating plate of the plate heater is equal to the ratio of the effective heat exchange area, the average velocity of the fluid in each heating plate is calculated; the Reynolds number of the fluid in each heating plate is calculated based on the average velocity of the fluid in each heating plate, and the flow state of the fluid in each heating plate of the plate heater is determined based on the Reynolds number of the fluid in each heating plate; the flow resistance of the fluid in each heating plate is calculated, and the highest heating plate is used as a reference, and throttling rings are installed on the inlet or outlet pipes of other heating plates to make the flow resistance of the fluid in all heating plates equal; the local resistance coefficient and diameter of the throttling ring of each heating plate are calculated. The internal resistance control method of the plate heater of the present application can effectively adjust the resistance between heating plates of different heights and the flow rate of high-temperature fluid in the heating plates, thereby improving the heat exchange efficiency of the plate heat exchanger.

Description

Technical Field

[0001] The present invention relates to the technical field of heater internal resistance control, and in particular to a method, system, computer equipment and readable storage medium for regulating the internal resistance of a plate-type heater. Background Art

[0002] The plate heater is a high-efficiency heat exchanger made of stacked metal plates of a certain shape. The cold and hot fluids are on both sides of the metal plate, respectively. The heat exchange area is large and the heat exchange resistance is small. Under the condition of equal pressure loss, the heat exchange capacity of the plate heat exchanger can reach 3-5 times that of the ordinary tube heat exchanger. In industrial processes, the fluid medium delivery pipeline is often compactly arranged and the pipeline space is limited. In order to efficiently heat the fluid medium, the plate heat exchanger becomes a good choice. If the fluid medium contains solid particles (such as dusty airflow), the horizontal arrangement of the metal plate may cause the deposition of solid particles, so the metal plate should be arranged vertically.

[0003] Figure 1 It is a typical plate heater structure. Three heating plates are arranged vertically in a circular pipe. The outside of the heating plate is the dusty airflow to be heated, and the inside of the heating plate is the high-temperature fluid. The high-temperature fluid enters and exits the heating plate at both ends of the heating plate, and the inlet and outlet pipes are connected to the inlet and outlet small headers respectively. The overall flow direction of the high-temperature fluid is opposite to the dusty airflow. The countercurrent arrangement of high and low temperature fluids can increase the overall heat exchange temperature difference of the heater, which is beneficial to improve the heat exchange efficiency. The high-temperature fluid channel inside the heating plate is arranged with folding partitions. The width of the channel at the top of the partition is consistent with the spacing between the partitions. Under the guiding effect of the partitions, the high-temperature fluid flows in a serpentine shape inside the heating plate, which can increase the flow velocity of the high-temperature fluid without changing the flow rate of the high-temperature fluid, enhance the heat exchange effect, and prevent the occurrence of a large range of flow dead angles. The heights of the three heating plates inside the circular tube are different, with the middle one being higher and the two sides being lower. Compared with the middle heating plate, the high-temperature fluid travel distance inside the heating plates on both sides is shorter, resulting in smaller flow resistance of the high-temperature fluid and larger flow rate of the high-temperature fluid. However, at the same time, the heat exchange area of ​​the heating plates on both sides in contact with the dust-laden airflow is smaller, that is, the flow resistance (flow rate) of the high-temperature fluid inside the heating plate does not match the heat exchange area of ​​the heating plate. Technical measures need to be taken to adjust the resistance of different high-temperature fluid channels to match it with the heat exchange area. Summary of the invention

[0004] The present invention provides a method, system, computer equipment and readable storage medium for regulating the internal resistance of a plate heater to solve the technical problem that the flow resistance (flow rate) of the high-temperature fluid inside the heating plate does not match the area of ​​the heating plate, and to adjust the resistance of different high-temperature fluid channels to match the heat exchange area.

[0005] In order to solve the above technical problems, in a first aspect, an embodiment of the present invention provides a method for controlling the internal resistance of a plate heater, the method comprising:

[0006] Based on the total flow rate of the fluid in the plate heater and the premise that the ratio of the flow rates of the fluid in each heating plate of the plate heater is equal to the ratio of the effective heat exchange areas, the average velocity of the fluid in each heating plate is calculated;

[0007] Calculating the Reynolds number of the fluid in each heating plate according to the average velocity of the fluid in each heating plate, and determining the flow state of the fluid in each heating plate of the plate-type heater according to the Reynolds number of the fluid in each heating plate; the flow state includes a turbulent state and a laminar state;

[0008] Calculating the flow resistance of the fluid in each heating plate according to the Reynolds number and flow state of the fluid in each heating plate, and obtaining the maximum value of the flow resistance of the fluid in the heating plate;

[0009] Install a throttling ring on the inlet pipe or outlet pipe of the heating plate whose fluid flow resistance in all the heating plates is less than the maximum fluid flow resistance in the heating plate, so as to make the fluid flow resistance in all the heating plates equal;

[0010] Calculate and determine the local resistance coefficient and diameter of the throttling ring of each heating plate.

[0011] In a further embodiment, the Reynolds number calculation formula of the fluid in each heating plate is:

[0012] Where V is the average velocity of the fluid in the heating plate, d is the equivalent diameter of the flow channel, and ν is the kinematic viscosity of the fluid;

[0013] The equivalent diameter calculation formula of the flow channel is:

[0014] Among them, A is the flow cross-sectional area, C is the contact length between the fluid and the solid wall on the flow cross-sectional area, a is the internal channel thickness of the heating plate, and b is the spacing between the internal partitions of the heating plate.

[0015] In a further embodiment, determining the flow state of the fluid in each heating plate of the plate-type heater according to the Reynolds number of the fluid in each heating plate comprises:

[0016] If the Reynolds number of the fluid in the heating plate is greater than the critical Reynolds number, the fluid flow in the heating plate enters a turbulent state;

[0017] If the Reynolds number of the fluid in the heating plate is not greater than the critical Reynolds number, the fluid flow in the heating plate enters a laminar flow state.

[0018] In a further embodiment, the calculating the flow resistance of the fluid in each heating plate according to the Reynolds number and the flow state of the fluid in each heating plate comprises:

[0019] Calculating the friction resistance along the fluid in each heating plate according to the Reynolds number of the fluid in each heating plate;

[0020] The calculation formula of the friction resistance along the way is: Among them, λ is the resistance coefficient along the process, l is the process length, and g is the gravitational acceleration;

[0021] The drag coefficient along the turbulent flow state is:

[0022] The drag coefficient along the laminar flow state is:

[0023] The process length calculation formula is: H is the height of the heating plate, and L is the length of the heating plate.

[0024] In a further embodiment, the calculating the flow resistance of the fluid in each heating plate according to the Reynolds number and the flow state of the fluid in each heating plate further includes:

[0025] The local resistance of the fluid in each heating plate at each turning point is calculated, and the local resistance calculation formula is: Where ξ is the local resistance coefficient at the turning point of the folding channel;

[0026] The local resistance and the local resistance of the fluid in each heating plate are calculated, and the local resistance and the local resistance are: Where N is the number of turns inside the heating plate;

[0027] The calculation formula for the number of internal turns of the heating plate is:

[0028] In a further embodiment, the calculating the flow resistance of the fluid in each heating plate according to the Reynolds number and the flow state of the fluid in each heating plate further includes:

[0029] The sum of the friction resistance along the fluid in each heating plate and the local resistance of the fluid in each heating plate is calculated to obtain the flow resistance of the fluid in each heating plate.

[0030] In a further embodiment, the calculating and determining the local resistance coefficient and diameter of the throttle ring of each heating plate includes:

[0031] Obtaining a first resistance value of a throttle ring in a heating plate where a throttle ring is installed according to the fluid flow resistance in each heating plate;

[0032] The second resistance value of the throttle ring in the throttle ring heating plate is calculated according to the throttle ring resistance calculation formula, and the throttle ring resistance calculation formula is: Among them, ξ0 is the local resistance coefficient of the throttle ring, V h is the average velocity of the fluid flowing through the throttling ring;

[0033] The average velocity calculation formula of the fluid flowing through the throttling ring is: Among them, d 20 is the diameter of the inlet and outlet pipes of the heating plate;

[0034] According to the first resistance value and the second resistance value of the throttling ring being equal, the local resistance coefficient of the throttling ring of each throttling ring-mounted heating plate is obtained by calculation.

[0035] The diameter of each throttling ring is obtained by calculation according to the relationship between the local resistance coefficient of the throttling ring, the inlet and outlet pipe diameters of the heating plate and the throttling ring diameter.

[0036] In a second aspect, an embodiment of the present invention provides a plate heater internal resistance control system, the system comprising:

[0037] The first calculation unit is used to calculate the average velocity of the fluid in each heating plate according to the total flow rate of the fluid in the plate heater and the premise that the ratio of the flow rates of the fluid in each heating plate of the plate heater is equal to the ratio of the effective heat exchange area;

[0038] A fluid flow state determination unit: used to calculate the Reynolds number of the fluid in each heating plate according to the average velocity of the fluid in each heating plate, and determine the flow state of the fluid in each heating plate of the plate heater according to the Reynolds number of the fluid in each heating plate; the flow state includes a turbulent state and a laminar state;

[0039] A second calculation unit is used to calculate the flow resistance of the fluid in each heating plate according to the Reynolds number and flow state of the fluid in each heating plate, and obtain the maximum value of the flow resistance of the fluid in the heating plate;

[0040] A throttle ring position determination unit: used for installing throttle rings on the inlet pipes or outlet pipes of the heating plates whose fluid flow resistance in all the heating plates is less than the maximum fluid flow resistance in the heating plates, so as to make the fluid flow resistance in all the heating plates equal;

[0041] The third calculation unit is used to calculate and determine the local resistance coefficient and diameter of the throttling ring of each heating plate.

[0042] In a third aspect, an embodiment of the present invention further provides a computer device, characterized in that it includes a memory, a processor and a transceiver, which are connected via a bus; the memory is used to store a set of computer program instructions and data, and can transmit the stored data to the processor, and the processor can execute the program instructions stored in the memory to execute the method described in the above claims.

[0043] In a fourth aspect, an embodiment of the present invention further provides a computer-readable storage medium, characterized in that a computer program is stored in the computer-readable storage medium, and when the computer program is executed, the method described in the above claims is implemented.

[0044] The embodiments of the present invention provide a method, system, computer device and computer storage medium for regulating the internal resistance of a plate heater. According to the total flow rate of the fluid in the plate heater, the average velocity of the fluid in each heating plate is calculated on the premise that the ratio of the fluid flow rate in each heating plate of the plate heater is equal to the ratio of the effective heat exchange area; the Reynolds number of the fluid in each heating plate is calculated according to the average velocity of the fluid in each heating plate, and the flow state of the fluid in each heating plate of the plate heater is determined according to the Reynolds number of the fluid in each heating plate; the flow resistance of the fluid in each heating plate is calculated, and the highest heating plate is used as a reference, and throttling rings are installed on the inlet or outlet pipes of other heating plates to make the flow resistance of the fluid in all heating plates equal; finally, the local resistance coefficient and diameter of the throttling ring of each heating plate are calculated. The internal resistance regulation method of the plate heater of the present application can effectively adjust the resistance between heating plates of different heights and the flow rate of high-temperature fluid in the heating plates, thereby improving the heat exchange efficiency of the plate heat exchanger. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] Figure 1 It is a structural diagram of a plate heater provided by an embodiment of the present invention;

[0046] Figure 2 It is a schematic diagram of the steps of a method for controlling the internal resistance of a plate-type heater provided in an embodiment of the present invention;

[0047] Figure 3 It is a dimension diagram of a plate heater provided by an embodiment of the present invention;

[0048] Figure 4 It is a schematic diagram of the installation position of the throttling ring in the plate-type heater provided by an embodiment of the present invention;

[0049] Figure 5 is a dimension diagram of another plate heater provided by an embodiment of the present invention;

[0050] Figure 6 is a schematic diagram of an internal resistance control system of a plate heater provided in an embodiment of the present invention;

[0051] Figure 7 is a schematic diagram of a computer device provided by an embodiment of the present invention;

[0052] Reference numerals:

[0053] 1-dust-laden air flow duct; 2-heating plate; 3-high-temperature fluid inlet pipe; 4-inlet small header; 5-high-temperature fluid outlet duct; 6-outlet small header; 7-high-temperature fluid channel; 8-folding spacer; 9-throttling ring. DETAILED DESCRIPTION

[0054] The following is a detailed description of the implementation of the present invention in conjunction with the accompanying drawings. The embodiments are provided only for illustrative purposes and cannot be understood as limiting the present invention. The accompanying drawings are only for reference and illustration purposes and do not constitute a limitation on the scope of patent protection of the present invention. 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.

[0055] First embodiment

[0056] See also Figure 2 In an embodiment of the present invention, a method for controlling the internal resistance of a plate heater is provided, the method comprising the following steps S1-S5:

[0057] S1. Based on the total flow rate of the fluid in the plate heater and the premise that the ratio of the fluid flow rates in each heating plate of the plate heater is equal to the ratio of the effective heat exchange areas, the average velocity of the fluid in each heating plate is calculated.

[0058] S2. Calculate the Reynolds number of the fluid in each heating plate according to the average velocity of the fluid in each heating plate, and determine the flow state of the fluid in each heating plate of the plate-type heater according to the Reynolds number of the fluid in each heating plate; the flow state includes a turbulent state and a laminar state.

[0059] S3. Calculate the flow resistance of the fluid in each heating plate according to the Reynolds number and flow state of the fluid in each heating plate, and obtain the maximum value of the flow resistance of the fluid in the heating plate.

[0060] S4. Install throttling rings on the inlet pipes or outlet pipes of the heating plates whose fluid flow resistance is less than the maximum value of the fluid flow resistance in the heating plates, so as to make the fluid flow resistance in all the heating plates equal.

[0061] S5. Calculate and determine the local resistance coefficient and diameter of the throttling ring of each heating plate.

[0062] In the embodiment of the present application, Figure 1The plate heater shown in the figure is a circular dust-containing airflow duct 1. The heating plate 2 of the plate heater is evenly arranged vertically in the circular dust-containing airflow duct 1. The outside of the heating plate 2 is the dust-containing airflow to be heated. The inside of the heating plate 2 is the high-temperature fluid. The positions of the high-temperature fluid inlet pipe 3 and the high-temperature fluid outlet pipe 5 are respectively located at the two ends of the heating plate. The inlet pipe of the high-temperature fluid inlet pipe 3 and the outlet pipe of the high-temperature fluid outlet pipe 5 are circular and are respectively connected to the inlet small header 4 and the outlet small header 5, so that the pressure drop of the high-temperature fluid in each heating plate is the same. The pressure drop of the fluid in each heating plate is positively correlated with the flow resistance of the fluid in the heating plate. The high-temperature fluid channel 7 inside the heating plate 2 is arranged with a folding spacer 8. The width of the channel at the top of the folding spacer 8 is consistent with the spacing of the folding spacer 8. Under the guiding effect of the folding spacer 8, the high-temperature fluid flows in a serpentine shape inside the heating plate 2, which can increase the flow speed of the high-temperature fluid without changing the flow rate of the high-temperature fluid, enhance the heat exchange effect, and prevent the occurrence of a large range of flow dead angles. The heights of the heating plates 2 inside the circular tube dust-laden airflow duct 1 are different, with the middle being higher and the two sides being lower. Compared with the middle heating plate, the high-temperature fluid travel distance inside the heating plates on both sides is shorter, resulting in a smaller flow resistance of the high-temperature fluid, a larger average velocity of the fluid, and a larger flow rate of the high-temperature fluid. However, at the same time, the heat exchange area of ​​the heating plates on both sides in contact with the dust-laden airflow is smaller, that is, the flow resistance (flow rate) of the high-temperature fluid inside the heating plate does not match the heat exchange area of ​​the heating plate 2.

[0063] When the ratio of the high-temperature fluid flow rates in different heating plates is equal to the ratio of the effective heat exchange areas of the heating plates, the heat exchange efficiency of the heat exchanger is the highest. Figure 3 The height of the heating plate in the middle of the plate heater shown is the highest, which is defined as the highest heating plate, represented by 0. The height of the heating plates at the corresponding positions on both sides and the average velocity of the fluid in the heating plates are equal. n represents the nth heating plate that needs to be installed with a throttling ring. Considering that the spacing between the internal spacers of different heating plates is equal, the thickness of the heating plates is equal, that is, the cross-sectional area of ​​the high-temperature fluid flow is equal, then the ratio of the fluid flow rates inside different heating plates is equal to the ratio of the average velocities inside the heating plates, that is, Different heating plates have the same length, and the ratio of their effective heat exchange areas is equal to the ratio of their heights, that is, Therefore In order to make the ratio of the average speed of different heating plates equal to the ratio of the height of the heating plates, we can install throttling rings on the inlet or outlet pipes of the low heating plates on both sides to increase the flow resistance of the fluid in the low heating plates on both sides and reduce the average speed of the fluid, such as Figure 4 The figure shows the schematic diagram of the installation position of the throttling ring.

[0064] According to the above analysis, Where V0 is the average velocity of the fluid at the highest heating plate, V nis the average speed of the nth heating plate that needs to be installed with a throttling ring, H0 is the height of the highest heating plate, H n is the height of the nth heating plate where the throttling ring needs to be installed. The total flow rate Q of the heating plate is a known quantity, which can be obtained Wherein, a is the thickness of the channel inside the heating plate, and b is the spacing between the spacers inside the heating plate.

[0065] The flow state of fluid is divided into laminar flow and turbulent flow. Under laminar flow, the resistance along the fluid is proportional to the first power of the average flow velocity of the fluid. Under turbulent flow, the resistance along the fluid is approximately proportional to the second power of the flow velocity of the fluid. If you want to calculate the flow resistance of the fluid, you need to determine the flow state of the fluid first.

[0066] The flow state of the fluid is closely related to the Reynolds number Re of the fluid. The physical meaning of the Reynolds number Re is the ratio of the inertial force of the fluid particle motion to the viscous resistance. The calculation formula is:

[0067]

[0068] Where V is the average velocity of the fluid in the heating plate, d is the equivalent diameter of the flow channel, and ν is the kinematic viscosity of the fluid; the calculation formula for the equivalent diameter d is:

[0069]

[0070] Where A is the flow cross-sectional area, C is the contact length between the fluid and the solid wall on the flow cross section, that is, the wetted perimeter, a is the internal channel thickness of the heating plate, and b is the spacing between the internal spacers of the heating plate.

[0071] If the Reynolds number of the fluid in the heating plate is greater than the critical Reynolds number, the fluid flow in the heating plate enters a turbulent state; if the Reynolds number of the fluid in the heating plate is not greater than the critical Reynolds number, the fluid flow in the heating plate enters a laminar state.

[0072] In engineering practice, when the Reynolds number Re is greater than 2300, it is generally considered that the flow enters a turbulent state, and vice versa. Therefore, if the Reynolds number of the fluid in the heating plate is greater than 2300, the flow of the fluid in the heating plate enters a turbulent state; if the Reynolds number of the fluid in the heating plate is not greater than 2300, the flow of the fluid in the heating plate enters a laminar state.

[0073] The fluid flow resistance can be divided into two parts: friction resistance along the way and local resistance, which are calculated separately in the embodiment of the present invention.

[0074] Calculation of friction resistance along the fluid

[0075] Friction resistance of fluid along the path h f The calculation formula is as follows:

[0076] Among them, λ is the resistance coefficient along the process, l is the process length, and g is the gravitational acceleration;

[0077] The drag coefficient along the turbulent flow state is:

[0078] The drag coefficient along the laminar flow state is:

[0079] The process length calculation formula is: Wherein, H is the height of the heating plate, and L is the length of the heating plate.

[0080] Calculation of local fluid resistance

[0081] Under the action of the folding strips inside the heating plate, the high-temperature fluid flows in a serpentine manner inside the heating plate. Each time it turns, a local resistance is generated. Since the sum of multiple local resistances generated by the serpentine flow is much larger than the local resistance generated by the inlet and outlet of the heating plate, it is approximately considered that the local resistance of the high-temperature fluid flow inside the heating plate is equal to the sum of the local resistances generated by each serpentine turn. The number of turns inside the heating plate N is:

[0082]

[0083] The calculation formula for the local resistance of the fluid in each heating plate at each turning point is: Where ξ is the local resistance coefficient at the turning point of the folding channel;

[0084] Calculate the local resistance and the local resistance of the fluid in each heating plate. The local resistance and the local resistance of each heating plate are:

[0085] Calculate the sum of the friction resistance along the fluid in each heating plate and the local resistance of the fluid in each heating plate to obtain the flow resistance of the fluid in each heating plate. The calculation formula is:

[0086]

[0087] Laminar flow state:

[0088]

[0089] Turbulent state:

[0090]

[0091] The flow resistance of the fluid in each heating plate can be obtained by substituting the calculated average velocity of the fluid in each heating plate into the calculation formula of the fluid flow resistance.

[0092] Install throttling rings on both sides of the heating plates to make the fluid flow resistance in the two sides of the heating plates equal to the fluid flow resistance in the middle heating plate, that is, Where h0 is the fluid flow resistance of the highest heating plate in the middle, h n is the fluid flow resistance of the nth heating plate that needs to be equipped with a throttling ring, The fluid flow resistance of the throttling ring in the nth heating plate that needs to be installed with a throttling ring. Since the flow resistance of the fluid in each heating plate has been calculated, the fluid flow resistance of the throttling ring installed in the nth heating plate that needs to be installed with a throttling ring can be obtained, which is determined as the first resistance value of the throttling ring in the nth heating plate that needs to be installed with a throttling ring.

[0093] The fluid flow resistance of the throttling ring can be regarded as a local resistance. According to the local resistance calculation formula, the fluid flow resistance calculation formula of the throttling ring can be obtained: Among them, ξ0 is the local resistance coefficient of the throttle ring, The average velocity of the fluid flowing through the throttling ring in the nth heating plate that needs to be installed with a throttling ring is determined as the second resistance value of the throttling ring in the nth heating plate that needs to be installed with a throttling ring.

[0094] The throttle ring is installed on the channel of the inlet or outlet of the heating plate. The flow rate flowing through the throttle ring is equal to the flow rate flowing through the heating plate. Therefore, the average flow velocity of the fluid inside the throttle ring and the average velocity of the fluid in the heating plate are related to each other as follows: Among them, d 20 is the diameter of the inlet and outlet pipes of the heating plate, such as Figure 3 As shown, the inlet and outlet pipes of the heating plate are connected to the small header and are circular pipes.

[0095] The first resistance value and the second resistance value of the throttling ring in the nth heating plate where the throttling ring needs to be installed are equal, and the local resistance coefficient of the throttling ring installed in the nth heating plate where the throttling ring needs to be installed is calculated;

[0096] According to the calculation formula of the local resistance coefficient of the throttle ring: Among them, d 21 is the diameter of the throttling ring, and the diameter of each throttling ring is obtained by calculation.

[0097] Second embodiment

[0098] Based on the first embodiment, the present invention combines the relevant data parameters of the specific plate heater to provide a specific application implementation case of the technical solution of the present invention, such as Figure 5 As shown, it is a plate heater with three heating plates, and the internal high temperature fluid has a kinematic viscosity of ν = 10 -6 m 2 / s, total flow Q = 5m 3 / h, heating plate length L = 5m, middle height H0 = 0.8m, height of the first heating plate on both sides H1 = 0.6m, thickness of fluid channel inside the heating plate a = 0.01m, spacing of folding strips b = 0.1m, diameter of inlet and outlet pipes of the heating plate d20 =0.01m, a throttling ring with a large aperture should be installed on the first heating plate on both sides to match the internal resistance of the middle heating plate and the first heating plates on both sides, so that the ratio of the high-temperature fluid flow in the middle heating plate and the first heating plates on both sides is equal to the ratio of the effective heat exchange area of ​​the heating plates.

[0099] Determination of flow state inside the heating plate:

[0100] Q=5m 3 / h=0.00139m 3 / s

[0101]

[0102] Q=Q0+2Q1=ab(V0+2V1)=0.001(V0+2V1)

[0103] According to the above formula, V0=0.555m / s, V1=0.417m / s.

[0104] Calculate the flow Reynolds number Re

[0105]

[0106]

[0107] The internal flows of the middle heating plate and the first heating plates on both sides are in a turbulent state.

[0108] Calculation of flow resistance inside the heating plate:

[0109] Calculation of flow resistance inside the intermediate heating plate:

[0110]

[0111] Calculation of internal flow resistance of the first heating plate on both sides (before adding throttling ring)

[0112]

[0113] After installing throttle rings on the inlet or outlet pipes of the first heating plate on both sides, the throttle ring size calculation is:

[0114]

[0115] The local resistance coefficient of the throttle ring is calculated to be ξ0=0.29.

[0116] according to Among them, d 21 is the throttle ring diameter, calculated to obtain d 21=0.0065m, that is, adding a throttling ring with a diameter of 0.0065m on the inlet (or outlet) pipe of the first heating plate on both sides can match the resistance of the middle heating plate and the first heating plates on both sides, so that the ratio of the high-temperature fluid flow rate inside the middle heating plate and the first heating plates on both sides is equal to the ratio of the effective heat exchange area of ​​the heating plates.

[0117] In an embodiment of the present invention, in order to solve the problem of mismatch between the internal resistance of heating plates at different heights in a plate heater and the heat exchange capacity of the heating plates, a method for controlling the internal resistance of a plate heater is provided. According to the total flow rate of the fluid in the plate heater, the average velocity of the fluid in each heating plate is calculated on the premise that the ratio of the fluid flow rate in each heating plate of the plate heater is equal to the ratio of the effective heat exchange area; the Reynolds number of the fluid in each heating plate is calculated according to the average velocity of the fluid in each heating plate, and the flow state of the fluid in each heating plate of the plate heater is determined according to the Reynolds number of the fluid in each heating plate; the flow resistance of the fluid in each heating plate is calculated, and the highest heating plate is used as a reference. A throttling ring is installed on the inlet or outlet pipes of other heating plates to make the flow resistance of the fluid in all heating plates equal; finally, the local resistance coefficient and diameter of the throttling ring of each heating plate are calculated. The resistance between different heating plates and the flow rate of high-temperature fluid are regulated, thereby improving the heat exchange efficiency of the plate heat exchanger.

[0118] Third embodiment

[0119] Accordingly, if Figure 6 As shown, based on a method for controlling the internal resistance of a plate heater, an embodiment of the present invention further provides a system for controlling the internal resistance of a plate heater, the system comprising:

[0120] The first calculation unit 1 is used to calculate the average velocity of the fluid in each heating plate according to the total flow rate of the fluid in the plate heater and the premise that the ratio of the flow rates of the fluid in each heating plate of the plate heater is equal to the ratio of the effective heat exchange area;

[0121] Fluid flow state determination unit 2: used to calculate the Reynolds number of the fluid in each heating plate according to the average velocity of the fluid in each heating plate, and determine the flow state of the fluid in each heating plate of the plate heater according to the Reynolds number of the fluid in each heating plate; the flow state includes a turbulent state and a laminar state;

[0122] The second calculation unit 3 is used to calculate the flow resistance of the fluid in each heating plate according to the Reynolds number and flow state of the fluid in each heating plate, and obtain the maximum value of the flow resistance of the fluid in the heating plate;

[0123] A throttle ring position determination unit 4 is used to install throttle rings on the inlet pipes or outlet pipes of the heating plates whose fluid flow resistance in all the heating plates is less than the maximum fluid flow resistance in the heating plates, so as to make the fluid flow resistance in all the heating plates equal;

[0124] The third calculation unit 5 is used to calculate and determine the local resistance coefficient and diameter of the throttling ring of each heating plate.

[0125] For the specific definition of a plate heater internal resistance control system, please refer to the above-mentioned definition of a plate heater internal resistance control method, which will not be repeated here. A person of ordinary skill in the art can appreciate that the various modules and steps described in conjunction with the embodiments disclosed in this application can be implemented in hardware, software, or a combination of both. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professional and technical personnel can use different methods to implement the described functions for each specific application, but such implementation should not be considered to be beyond the scope of this application.

[0126] Fourth embodiment

[0127] like Figure 7 As shown, a computer device provided by an embodiment of the present invention includes a memory, a processor and a transceiver, which are connected via a bus; the memory is used to store a set of computer program instructions and data, and can transmit the stored data to the processor, and the processor can execute the program instructions stored in the memory to execute the steps of the above-mentioned plate heater internal resistance control method.

[0128] The memory may include a volatile memory or a non-volatile memory, or may include both volatile and non-volatile memories; the processor may be a central processing unit, a microprocessor, an application-specific integrated circuit, a programmable logic device, or a combination thereof. By way of example but not limitation, the programmable logic device may be a complex programmable logic device, a field programmable gate array, a general purpose array logic, or any combination thereof.

[0129] Additionally, the memory may be a physically separate unit or may be integrated with the processor.

[0130] It can be understood by those skilled in the art that Figure 7 The structure shown in the figure is only a block diagram of a part of the structure related to the solution of the present application, and does not constitute a limitation on the computer device to which the solution of the present application is applied. The specific computer device may include more or fewer components than those shown in the figure, or combine certain components, or have the same component arrangement.

[0131] Fifth embodiment

[0132] In one embodiment, a computer-readable storage medium is provided, wherein the storage medium is used to store one or more computer programs, wherein the one or more computer programs include program codes, and when the computer programs are run on a computer, the program codes are used to execute the above-mentioned method for controlling the internal resistance of a plate heater.

[0133] In the above embodiments, it can be implemented in whole or in part by software, hardware, firmware or any combination thereof. When implemented by software, it can be implemented in whole or in part in the form of a computer program product. The computer program product includes one or more computer instructions. When the computer program instructions are loaded and executed on a computer, the process or function described in the embodiment of the present invention is generated in whole or in part. The computer can be a general-purpose computer, a special-purpose computer, a computer network, or other programmable device. The computer instructions can be stored in a computer-readable storage medium, or transmitted from one computer-readable storage medium to another computer-readable storage medium. For example, the computer instructions can be transmitted from a website site, computer, server or data center by wired (e.g., coaxial cable, optical fiber, digital subscriber line or wireless (e.g., infrared, wireless, microwave, etc.) mode to another website site, computer, server or data center. The computer-readable storage medium can be any available medium that a computer can access or a data storage device such as a server or data center that includes one or more available media integrated. The available medium can be a magnetic medium (e.g., a floppy disk, a hard disk, a tape), an optical medium (e.g., a DVD), or a semiconductor medium (e.g., an SSD), etc.

[0134] Those skilled in the art will appreciate that all or part of the processes in the above-mentioned embodiment methods can be implemented by instructing related hardware through a computer program. The computer program can be stored in a computer-readable storage medium. When the computer program is executed, it can include the processes of the embodiments of the above-mentioned methods.

[0135] In this embodiment, a method, system, computer device and computer storage medium for regulating the internal resistance of a plate heater are provided, which is aimed at the technical problem that the flow resistance (flow rate) of the high-temperature fluid inside the heating plate does not match the area of ​​the heating plate. This application is based on the total flow rate of the fluid in the plate heater, and the ratio of the fluid flow rate in each heating plate of the plate heater is equal to the ratio of the effective heat exchange area. The average velocity of the fluid in each heating plate is calculated; the Reynolds number of the fluid in each heating plate is calculated according to the average velocity of the fluid in each heating plate, and the flow state of the fluid in each heating plate of the plate heater is determined according to the Reynolds number of the fluid in each heating plate; the flow resistance of the fluid in each heating plate is calculated, and the middle heating plate is used as a reference. A throttling ring is installed on the inlet or outlet pipes of the heating plates on both sides to make the flow resistance of the fluid in all heating plates equal; finally, the local resistance coefficient and diameter of the throttling ring of each heating plate are calculated. The resistance between different heating plates and the flow rate of the high-temperature fluid are regulated, thereby improving the heat exchange efficiency of the plate heat exchanger.

[0136] The above-mentioned embodiments only express several preferred implementation modes of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the invention patent. It should be pointed out that, for ordinary technicians in the technical field, several improvements and substitutions can be made without departing from the technical principles of the present invention, and these improvements and substitutions should also be regarded as the protection scope of the present application. Therefore, the protection scope of the patent of the present application shall be based on the protection scope of the claims.

Claims

1. A method for controlling the internal resistance of a plate heater, characterized in that: The method comprises: Based on the total flow rate of the fluid in the plate heater and the premise that the ratio of the flow rates of the fluid in each heating plate of the plate heater is equal to the ratio of the effective heat exchange areas, the average velocity of the fluid in each heating plate is calculated; Calculating the Reynolds number of the fluid in each heating plate according to the average velocity of the fluid in each heating plate, and determining the flow state of the fluid in each heating plate of the plate-type heater according to the Reynolds number of the fluid in each heating plate; the flow state includes a turbulent state and a laminar state; Calculating the flow resistance of the fluid in each heating plate according to the Reynolds number and flow state of the fluid in each heating plate, and obtaining the maximum value of the flow resistance of the fluid in the heating plate; Install a throttling ring on the inlet pipe or outlet pipe of the heating plate whose fluid flow resistance in all the heating plates is less than the maximum fluid flow resistance in the heating plate, so as to make the fluid flow resistance in all the heating plates equal; Calculate and determine the local resistance coefficient and diameter of the throttling ring of each heating plate.

2. The method for controlling the internal resistance of a plate heater according to claim 1, characterized in that: The Reynolds number calculation formula of the fluid in each heating plate is: Where V is the average velocity of the fluid in the heating plate, d is the equivalent diameter of the flow channel, and ν is the kinematic viscosity of the fluid; The equivalent diameter calculation formula of the flow channel is: Among them, A is the flow cross-sectional area, C is the contact length between the fluid and the solid wall on the flow cross-sectional area, a is the internal channel thickness of the heating plate, and b is the spacing between the internal partitions of the heating plate.

3. The method for controlling the internal resistance of a plate heater according to claim 2, characterized in that: The method of determining the flow state of the fluid in each heating plate of the plate-type heater according to the Reynolds number of the fluid in each heating plate comprises: If the Reynolds number of the fluid in the heating plate is greater than the critical Reynolds number, the fluid flow in the heating plate enters a turbulent state; If the Reynolds number of the fluid in the heating plate is not greater than the critical Reynolds number, the fluid flow in the heating plate enters a laminar flow state.

4. The method for controlling the internal resistance of a plate heater according to claim 3, characterized in that: The calculating the flow resistance of the fluid in each heating plate according to the Reynolds number and the flow state of the fluid in each heating plate comprises: Calculating the friction resistance along the fluid in each heating plate according to the Reynolds number of the fluid in each heating plate; The calculation formula of the friction resistance along the way is: Among them, λ is the resistance coefficient along the process, l is the process length, and g is the gravitational acceleration; The drag coefficient along the turbulent flow state is: The drag coefficient along the laminar flow state is: The process length calculation formula is: H is the height of the heating plate, and L is the length of the heating plate.

5. The method for controlling the internal resistance of a plate heater according to claim 4, characterized in that: The calculating the flow resistance of the fluid in each heating plate according to the Reynolds number and the flow state of the fluid in each heating plate also includes: The local resistance of the fluid in each heating plate at each turning point is calculated, and the local resistance calculation formula is: Where ξ is the local resistance coefficient at the turning point of the folding channel; The local resistance and the local resistance of the fluid in each heating plate are calculated, and the local resistance and the local resistance are: Where N is the number of turns inside the heating plate; The calculation formula for the number of internal turns of the heating plate is:

6. The method for controlling the internal resistance of a plate heater according to claim 5, characterized in that: The calculating the flow resistance of the fluid in each heating plate according to the Reynolds number and the flow state of the fluid in each heating plate also includes: The sum of the friction resistance along the fluid in each heating plate and the local resistance of the fluid in each heating plate is calculated to obtain the flow resistance of the fluid in each heating plate.

7. The method for controlling the internal resistance of a plate heater according to claim 6, characterized in that: The calculating and determining the local resistance coefficient and diameter of the throttling ring of each heating plate includes: Obtaining a first resistance value of a throttle ring in a heating plate where a throttle ring is installed according to the fluid flow resistance in each heating plate; The second resistance value of the throttle ring in the throttle ring heating plate is calculated according to the throttle ring resistance calculation formula, and the throttle ring resistance calculation formula is: Among them, ξ0 is the local resistance coefficient of the throttle ring, V h is the average velocity of the fluid flowing through the throttling ring; The average velocity calculation formula of the fluid flowing through the throttling ring is: Among them, d 20 is the diameter of the inlet and outlet pipes of the heating plate; According to the equality of the first resistance value and the second resistance value of the throttling ring, the local resistance coefficient of the throttling ring of each throttling ring heating plate is calculated; The diameter of each throttling ring is obtained by calculation according to the relationship between the local resistance coefficient of the throttling ring, the inlet and outlet pipe diameters of the heating plate and the throttling ring diameter.

8. A plate heater internal resistance control system, characterized in that: The system comprises: The first calculation unit is used to calculate the average velocity of the fluid in each heating plate according to the total flow rate of the fluid in the plate heater and the premise that the ratio of the flow rates of the fluid in each heating plate of the plate heater is equal to the ratio of the effective heat exchange area; A fluid flow state determination unit: used to calculate the Reynolds number of the fluid in each heating plate according to the average velocity of the fluid in each heating plate, and determine the flow state of the fluid in each heating plate of the plate heater according to the Reynolds number of the fluid in each heating plate; the flow state includes a turbulent state and a laminar state; A second calculation unit is used to calculate the flow resistance of the fluid in each heating plate according to the Reynolds number and flow state of the fluid in each heating plate, and obtain the maximum value of the flow resistance of the fluid in the heating plate; A throttle ring position determination unit: used for installing throttle rings on the inlet pipes or outlet pipes of the heating plates whose fluid flow resistance in all the heating plates is less than the maximum fluid flow resistance in the heating plates, so as to make the fluid flow resistance in all the heating plates equal; The third calculation unit is used to calculate and determine the local resistance coefficient and diameter of the throttling ring of each heating plate.

9. A computer device, characterized in that: It includes a memory, a processor and a transceiver, which are connected via a bus; the memory is used to store a set of computer program instructions and data, and can transmit the stored data to the processor, and the processor can execute the program instructions stored in the memory to perform the method as described in any one of claims 1 to 7.

10. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores a computer program, and when the computer program is executed, the method according to any one of claims 1 to 7 is implemented.

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