Heat transfer amount generation method and system for shell-and-tube heat exchanger

Abstract

The present application provides a method and a system for generating the heat transfer amount of a shell-and-tube heat exchanger. The method includes the following steps: establishing an o-xyz three-dimensional coordinate system for the shell-and-tube heat exchanger, and obtaining a first regional division plan view generated according to the yoz plane and a second regional division plan view generated according to the xoz plane; positioning any heat exchange unit R(i, j, k) according to the first regional division plan view and the second regional division plan view; obtaining the heat transfer coefficient h(i, j, k), the heat exchange area a(i, j, k), and the heat transfer temperature difference Δt(i, j, k) for any heat exchange unit R(i, j, k); and calculating and generating the heat transfer amount of any heat exchange unit R(i, j, k) by using the following formula: The method and system for generating the heat transfer amount of the shell-and-tube heat exchanger of the present application can more accurately obtain the internal heat transfer amount parameters of the shell-and-tube heat exchanger.

Description

Technical Field

[0001] This application mainly relates to the field of heat exchangers, and particularly to a method and system for generating heat transfer amount of a shell-and-tube heat exchanger. Background Art

[0002] As an important device for heat transfer, shell-and-tube heat exchangers are widely used in many industries such as energy, chemical engineering, and refrigeration. The design of their thermodynamic performance and structural integrity is crucial. In a shell-and-tube heat exchanger, two fluids are separated by a heat transfer surface (wall surface). When there is a temperature difference between the cold and hot fluids on both sides of the heat transfer surface, a driving force for heat transfer from the hot side to the cold side is generated. The goal of heat exchanger heat transfer calculation is to establish the relationship between the heat flow rate q, the heat transfer area A, the heat capacity C of each fluid, the overall heat transfer coefficient U, and the fluid terminal temperatures.

[0003] In classical heat transfer theory, there are some relatively conventional methods for calculating heat transfer amount, such as the effectiveness method (ε-NTU), the temperature efficiency method (P-NTU), the mean temperature difference method, the dimensionless mean temperature difference - temperature efficiency method (ψ-P), and the P1-P2 method, etc. However, these methods are all based on some idealized assumptions. One of the main assumptions is that the overall heat transfer coefficient U of the heat exchanger remains constant throughout the heat exchanger. However, the actual U depends on the magnitude of the continuous thermal resistance, especially the heat transfer coefficients on both fluid sides. These independent heat transfer coefficients will change with factors such as the fluid Reynolds number, the geometry of the heat transfer surface, the thermophysical properties of the fluid, and the entrance length effect caused by the development of the thermal boundary layer, resulting in the situation that the overall heat transfer coefficient U is not constant and inconsistent throughout the exchange process.

[0004] Therefore, there is still a lack of a relatively accurate way to obtain the heat transfer amount for shell-and-tube heat exchangers in this field. Summary of the Invention

[0005] The technical problem to be solved by this application is to provide a method and system for generating heat transfer amount of a shell-and-tube heat exchanger, which can more accurately obtain the internal heat transfer amount parameters of the shell-and-tube heat exchanger.

[0006] To solve the above technical problems, the present application provides a method for generating the heat transfer amount of a shell-and-tube heat exchanger. The shell-and-tube heat exchanger includes a shell, shell-side and tube-side inlet and outlet nozzles, and a tube bundle composed of a plurality of heat transfer tubes. The internal space of the tube bundle forms the tube side of the shell-and-tube heat exchanger, and the space between the tube bundle and the shell forms the shell side of the shell-and-tube heat exchanger. The method includes the following steps: establishing an o-xyz three-dimensional coordinate system for the shell-and-tube heat exchanger, and obtaining a first regional division plan view generated according to the yoz plane and a second regional division plan view generated according to the xoz plane; positioning any heat exchange unit R(i, j, k) according to the first regional division plan view and the second regional division plan view, where i, j, and k respectively correspond to the positions of the any heat exchange unit R(i, j, k) in the yoz plane, the xoz plane, and the xoy plane; obtaining the heat transfer coefficient h(i, j, k), the heat transfer area a(i, j, k), and the average heat transfer temperature difference Δt(i, j, k) for the any heat exchange unit R(i, j, k); and calculating and generating the heat transfer amount of the any heat exchange unit R(i, j, k) using the following formula:

[0007] Optionally, it further includes calibrating the shell-side inlet, the shell-side outlet, the tube-side inlet, and the tube-side outlet respectively according to the positions of the shell-side and tube-side inlet and outlet nozzles in the first regional division plan view, and calibrating a plurality of shell-side division planes parallel to the xoz plane and arranged along the y-axis direction, a plurality of tube-side division planes parallel to the xoy plane and arranged along the z-axis direction, and a plurality of longitudinal division planes of the shell parallel to the yoz plane and arranged along the x-axis direction in the first regional division plan view and the second regional division plan view according to the positions of the shell-side inlet, the shell-side outlet, the tube-side inlet, and the tube-side outlet. Wherein, a plurality of shell-side division layers are formed between every two adjacent shell-side division planes or between the shell-side division plane and the boundary of the shell side; a plurality of tube-side division layers are formed between every two adjacent tube-side division planes or between the tube-side division plane and the boundary of the tube side; a plurality of longitudinal division layers of the shell are formed between every two adjacent longitudinal division planes of the shell or between the longitudinal division plane of the shell and the boundary of the shell; and i, j, and k respectively represent the longitudinal division layer of the shell, the shell-side division layer, and the tube-side division layer where the any heat exchange unit R(i, j, k) is located.

[0008] Optionally, it further includes setting the positions of the plurality of shell-side division planes to be consistent with the positions of the baffles inside the shell-and-tube heat exchanger.

[0009] Optionally, it further includes defining the starting heat exchange unit R(1, 1, 1), and obtaining the values of i, j, and k according to the relative position relationship between any other heat exchange unit R(i, j, k) and the starting heat exchange unit R(1, 1, 1) in the shell-and-tube heat exchanger, wherein the starting heat exchange unit R(1, 1, 1) is the unit closest to the origin of coordinates in the xoz plane among the longitudinal layers of the shell where the shell-side inlet is located.

[0010] Optionally, it further includes calculating the heat transfer area a(i, j, k) through the following formula:

[0011]

[0012] where n is the uniform distribution density of the tube bundle in the xoz plane, Ns is the number of layers of the shell-side divided layers along the y-axis direction, S is the cross-sectional area of the shell in the xoz plane, A is the total outer surface heat transfer area of the tube bundle, and s(i, k) is the cross-sectional area of the heat exchange unit of any heat exchange unit R(i, j, k) in the xoz plane.

[0013] Optionally, it further includes calculating the tube-side heat transfer coefficient h of the tube side corresponding to the shell-and-tube heat exchanger t , the shell-side heat transfer coefficient h of the shell side corresponding to the shell-and-tube heat exchanger s and the tube wall thermal resistance, so as to calculate the heat transfer coefficient h(i, j, k) corresponding to any heat exchange unit R(i, j, k) according to the tube-side heat transfer coefficient h t , the shell-side heat transfer coefficient h s and the tube wall thermal resistance.

[0014] Optionally, it further includes calculating the shell-side heat transfer coefficient h using the Zhukauskas correlation s , and calculating the tube-side heat transfer coefficient h using the Gnielinski formula t .

[0015] Optionally, it further includes calculating the heat transfer coefficient h(i, j, k) through the following formula,

[0016]

[0017] where λ δ is the tube wall thermal conductivity of the heat transfer tube, r t , r s are the inner and outer wall fouling thermal resistances of the heat transfer tube respectively, δ t is the wall thickness of the heat transfer tube, and d0 and d t are the outer diameter and inner diameter of the heat transfer tube respectively.

[0018] Optionally, the heat transfer temperature difference Δt(i, j, k) is obtained as follows:

[0019] Δt(i, j, k) = t s (i, j, k) - t t (i, j, k),

[0020] wherein, t s and t t are the heat transfer unit temperatures on the shell side and the tube side in the shell-and-tube heat exchanger, respectively.

[0021] Optionally, the shell-and-tube heat exchanger includes a single-pass shell structure or a double-pass shell structure with a longitudinal baffle.

[0022] On the other hand, the present application also provides a heat transfer amount generation system for a shell-and-tube heat exchanger, including: a memory for storing instructions executable by a processor; and a processor for executing the instructions to implement the heat transfer amount generation method of the above shell-and-tube heat exchanger.

[0023] On the other hand, the present application also provides a computer-readable medium storing computer program code, and the computer program code implements the heat transfer amount generation method of the above shell-and-tube heat exchanger when executed by a processor.

[0024] Compared with the prior art, the present application has the following advantages: Compared with traditional heat exchanger design methods such as the effectiveness method, the thermal efficiency method, and the mean temperature difference method, the heat transfer amount generation method and system of the shell-and-tube heat exchanger in the present application can achieve more accurate heat exchanger design and obtain more accurate heat transfer and hydraulic calculation results. This method can avoid the influence of factors such as inconsistent heat transfer coefficients, and effectively solve the key and difficult problems in the heat exchanger design process such as phase change heat transfer, multi-tube pass structure, and temperature cross, and has good universality. In addition, the heat exchanger design results of the present invention can provide rich three-dimensional parameter information, including but not limited to: local heat transfer distribution, local pressure drop distribution, local temperature distribution, local flow velocity distribution, etc., so as to provide a basis for heat exchanger structure design optimization, thermal efficiency optimization, hydraulics optimization, flow-induced vibration analysis, mechanical evaluation, etc., and effectively improve the safety and economy of the heat exchanger. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] The accompanying drawings are provided to further understand the present application, and they are incorporated into and constitute a part of this application. The accompanying drawings illustrate the embodiments of the present application and, together with this specification, serve to explain the principles of the present application. In the accompanying drawings:

[0026] Figure 1 is a schematic flow chart of a heat transfer amount generation method for a shell-and-tube heat exchanger according to an embodiment of the present application;

[0027] Figure 2It is a schematic structural diagram of a shell-and-tube heat exchanger applicable to a heat transfer amount generation method of a shell-and-tube heat exchanger according to an embodiment of the present application;

[0028] Figure 3 and Figure 4 It is a schematic principle diagram of dividing the internal space of a shell-and-tube heat exchanger according to a three-dimensional coordinate system in a heat transfer amount generation method of a shell-and-tube heat exchanger according to an embodiment of the present application; and

[0029] Figure 5 It is a system block diagram of a heat transfer amount generation system of a shell-and-tube heat exchanger according to an embodiment of the present application. Detailed implementation manners

[0030] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the accompanying drawings required for description in the embodiments will be briefly introduced below. Obviously, the accompanying drawings in the following description are only some examples or embodiments of the present application. For those of ordinary skill in the art, without creative efforts, the present application can also be applied to other similar scenarios based on these drawings. Unless obvious from the language context or otherwise stated, the same reference numerals in the drawings represent the same structure or operation.

[0031] As shown in the present application and the claims, unless the context clearly indicates an exception, words such as "a", "an", "one" and / or "the" are not specifically singular, but may also include the plural. Generally speaking, the terms "comprising" and "including" only indicate the inclusion of the clearly identified steps and elements, and these steps and elements do not constitute an exclusive list. The method or device may also include other steps or elements.

[0032] Unless specifically stated otherwise, the relative arrangements of components and steps, numerical expressions and values described in these embodiments do not limit the scope of the present application. At the same time, it should be understood that for the convenience of description, the sizes of the various parts shown in the drawings are not drawn according to the actual proportional relationship. Technologies, methods and devices known to those of ordinary skill in the relevant fields may not be discussed in detail, but where appropriate, the said technologies, methods and devices should be regarded as part of the authorization specification. In all the examples shown and discussed here, any specific value should be interpreted as merely exemplary, rather than as a limitation. Therefore, other examples of the exemplary embodiments may have different values. It should be noted that similar reference numerals and letters represent similar items in the following drawings. Therefore, once an item is defined in one drawing, it does not need to be further discussed in subsequent drawings.

[0033] In the description of the present application, it should be understood that the orientation or positional relationship indicated by orientation words such as "front, back, up, down, left, right", "lateral, vertical, perpendicular, horizontal" and "top, bottom", etc. is usually based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing the present application and simplifying the description. Without contrary description, these orientation words do not indicate or imply that the device or element referred to must have a specific orientation or be constructed and operated in a specific orientation. Therefore, it should not be construed as a limitation on the protection scope of the present application; the orientation words "inside, outside" refer to the inside and outside relative to the contour of each component itself.

[0034] For convenience of description, spatial relative terms such as "above", "over", "on the upper surface", "above-mentioned", etc. can be used here to describe the spatial positional relationship between a device or feature shown in the figure and other devices or features. It should be understood that the spatial relative terms are intended to cover different orientations in use or operation in addition to the orientation described in the figure for the device. For example, if the device in the drawing is inverted, the device described as "above other devices or structures" or "over other devices or structures" will then be positioned "below other devices or structures" or "under other devices or structures". Thus, the exemplary term "above" can include both the orientations of "above" and "below". The device can also be positioned in other different ways (rotated 90 degrees or in other orientations), and corresponding interpretations should be made for the spatial relative descriptions used here.

[0035] In addition, it should be noted that using words such as "first", "second", etc. to limit components is only for the convenience of differentiating the corresponding components. Without additional statement, the above words have no special meaning. Therefore, it should not be construed as a limitation on the protection scope of the present application. In addition, although the terms used in the present application are selected from well-known and commonly used terms, some of the terms mentioned in the specification of the present application may be selected by the applicant according to his or her judgment, and their detailed meanings are described in the relevant parts of the description herein. In addition, it is required to understand the present application not only through the actual terms used, but also through the meaning implied by each term.

[0036] It should be understood that when a component is referred to as "on another component", "connected to another component", "coupled to another component", or "in contact with another component", it can be directly on, connected to, or coupled to, or in contact with the other component, or there may be an intervening component. In contrast, when a component is referred to as "directly on another component", "directly connected to", "directly coupled to", or "directly in contact with" another component, there is no intervening component. Similarly, when the first component is referred to as "electrically contacting" or "electrically coupled to" the second component, there is an electrical path allowing current flow between the first component and the second component. The electrical path may include capacitors, coupled inductors, and / or other components allowing current flow, even if there is no direct contact between the conductive components.

[0037] This application refers to Figure 1 A schematic flowchart of a heat transfer amount generation method 10 (hereinafter referred to as "method 10") for a shell-and-tube heat exchanger is presented. In this application Figure 1 Flowcharts are used to illustrate the operations performed by the systems according to the embodiments of this application. It should be understood that the operations described above or below are not necessarily executed precisely in sequence. Instead, the various steps can be executed in reverse order or simultaneously. Also, other operations can be added to these processes, or one or more steps can be removed from these processes.

[0038] To better understand method 10, reference is now made to Figure 2 First, a shell-and-tube heat exchanger 20 applicable to method 10 will be described. According to Figure 2 , the shell-and-tube heat exchanger 20 includes a shell 21, shell-and-tube side inlet and outlet nozzles, and a tube bundle 23 composed of a number of heat transfer tubes 230. Among them, the shell-and-tube side inlet and outlet nozzles specifically include a tube side inlet nozzle where the tube side inlet 221 is located, a tube side outlet nozzle where the tube side outlet 222 is located, a shell side inlet nozzle where the shell side inlet 223 is located, and a shell side outlet nozzle 224 where the shell side outlet 224 is located. The internal space of the tube bundle 23 forms the tube side of the shell-and-tube heat exchanger 20, and the space between the tube bundle 23 and the shell 21 forms the shell side of the shell-and-tube heat exchanger 20.

[0039] It can be understood that the heat transfer amount generation method for the shell-and-tube heat exchanger to be introduced below in this application is not limited to Figure 2The structure of the shell-and-tube heat exchanger 20 shown is applicable to the solution of this application for other shell-and-tube heat exchangers with the same details such as the inlet and outlet nozzles for the shell and tube sides. Exemplarily, the shell-and-tube heat exchanger 20 has a single-pass shell structure (such as the E-type heat exchanger in GB / T 151 of the national standard); in other embodiments of this application, a double-pass shell structure with a longitudinal baffle (such as the F-type heat exchanger in GB / T 151 of the national standard) can also be applicable. In such an embodiment, the longitudinal baffle divides the shell-side region in the shell into two parts through the longitudinal baffle. Additionally, preferably, considering factors such as system computing power, the solution of this application is applicable to single-phase heat exchangers.

[0040] Taking the structure of the shell-and-tube heat exchanger 20 as an example below, according to Figure 1 , the method 10 includes the following steps: Step 11 is to establish an o-xyz three-dimensional coordinate system for the shell-and-tube heat exchanger (such as the shell-and-tube heat exchanger 20 shown as Figure 2 ) and obtain a first regional division plan view generated according to the yoz plane and a second regional division plan view generated according to the xoz plane. Step 12 is to locate any heat exchange unit R(i, j, k) according to the first regional division plan view and the second regional division plan view; where i, j, and k respectively correspond to the positions of any heat exchange unit R(i, j, k) in the yoz plane, xoz plane, and xoy plane. Step 13 is to obtain the heat transfer coefficient h(i, j, k), the heat transfer area a(i, j, k), and the heat transfer temperature difference Δt(i, j, k) for any heat exchange unit R(i, j, k). Finally, step 14 is to calculate and generate the heat transfer amount of any heat exchange unit R(i, j, k) using the following formula:

[0041]

[0042] To better understand the above steps, now according to Figure 2 in the shell-and-tube heat exchanger 20 and Figure 3 and Figure 4 the schematic diagram of the principle of spatial division of the internal space in the shell-and-tube heat exchanger 20 shown according to the three-dimensional space is used to further introduce in detail one specific implementation solution of the method 10.

[0043] First, step 11 further includes respectively calibrating the shell-side inlet 223, the shell-side outlet 224, the tube-side inlet 221, and the tube-side outlet 222 in the first regional division plan view according to the positions of the inlet and outlet nozzles for the shell and tube sides, and according to the positions of the shell-side inlet 223, the shell-side outlet 224, the tube-side inlet 221, and the tube-side outlet 222 in the first regional division plan view 30 shown as Figure 3 and in the first regional division plan view shown as Figure 4In the second regional division plan view 40 shown, a plurality of shell-side division surfaces 31 parallel to the xoz plane and arranged in the y-axis direction, a plurality of tube-side division surfaces 32 parallel to the xoy plane and arranged in the z-axis direction, and a plurality of longitudinal shell division surfaces 41 parallel to the yoz plane and arranged in the x-axis direction are demarcated. Preferably, in this embodiment, it further includes setting that the positions of a plurality of shell-side division surfaces 31 are the same as those of the baffles 24 inside the shell-and-tube heat exchanger 20.

[0044] More specifically, referring to Figure 3 and Figure 4 , between every two adjacent shell-side division surfaces 31 or between the shell-side division surface 31 and the boundary of the shell side (i.e., Figure 3 the position of the short side edge of the largest rectangle shown), a plurality of shell-side division layers 310 are formed; between every two adjacent tube-side division surfaces 32 or between the tube-side division surface 32 and the boundary of the tube side (i.e., Figure 3 the position of the long side edge of the largest rectangle shown), a plurality of tube-side division layers 320 are formed; between every two adjacent longitudinal shell division surfaces 41 or between the longitudinal shell division surface and the boundary of the shell (i.e., Figure 4 the position of the circular edge shown), a plurality of longitudinal shell division layers 410 are formed. On this premise, the specific understanding of i, j, and k corresponding to the positions of any heat exchange unit R(i, j, k) in the yoz plane, xoz plane, and xoy plane in step 12 is: i, j, and k respectively represent the longitudinal shell division layer 410, shell-side division layer 310, and tube-side division layer 320 where any heat exchange unit R(i, j, k) is located. It can be understood that when demarcating each demarcation parameter in the first regional division plan view 30 and the second regional division plan view 40 described above, the information of the xoy plane in the three-dimensional space also needs to be considered, so as to locate the position of any heat exchange unit R(i, j, k) in the three-dimensional space. In addition, it should be noted that Figure 2 only schematically shows the internal structure of a shell-and-tube heat exchanger 20 to which the solution of the present application is applicable, and Figures 3 - 4 the division method in the three-dimensional space does not exactly correspond to the positions of the inlet and outlet nozzles of the shell and tube sides of the shell-and-tube heat exchanger 20. Therefore, the structure of the shell-and-tube heat exchanger that exactly corresponds to Figures 3 - 4 can be obtained by simply adjusting the positions of the inlet and outlet nozzles of the shell and tube sides on the basis of the shell-and-tube heat exchanger 20 shown in Figure 2 .

[0045] Referring to Figure 4, preferably in this embodiment, it further includes defining a starting heat exchange unit R(1, 1, 1), and obtaining the values of i, j, and k according to the relative position relationship between any other heat exchange unit R(i, j, k) and the starting heat exchange unit R(1, 1, 1) in the shell-and-tube heat exchanger 20. Exemplarily, preferably in this embodiment, the starting heat exchange unit R(1, 1, 1) is set as the unit closest to the coordinate origin in the xoz plane in the shell longitudinal layer 410 where the shell-side inlet 223 is located, that is Figure 4 the unit in the lower left corner of the second regional division plan view 40 shown in

[0046] Based on the above spatial division method in the three-dimensional coordinate system, in order to finally obtain the heat exchange amount in step 14, preferably in this embodiment, it further includes calculating the heat exchange area a(i, j, k) through the following formula:

[0047]

[0048] where n is the uniform distribution density of the tube bundle 23 shown in Figure 2 in the xoz plane, Ns is the number of layers of the shell-side division layer 310 in the y-axis direction, S is the cross-sectional area of the shell 21 in the xoz plane, A is the total external surface heat exchange area of the tube bundle 23, and s(i, k) is the cross-sectional area of any heat exchange unit R(i, j, k) in the xoz plane.

[0049] Furthermore, in this embodiment, it also includes calculating the tube-side heat transfer coefficient h t of the tube side corresponding to the tube side in the shell-and-tube heat exchanger 20, the shell-side heat transfer coefficient h s of the shell side corresponding to the shell side, and the tube wall thermal resistance, so as to calculate the heat transfer coefficient h(i, j, k) corresponding to any heat exchange unit R(i, j, k) according to the tube-side heat transfer coefficient h t , the shell-side heat transfer coefficient h s and the tube wall thermal resistance.

[0050] Preferably in this embodiment, the Zhukauskas correlation can be used to calculate the shell-side heat transfer coefficient h s , and the Gnielinski formula can be used to calculate the shell-side heat transfer coefficient h t .

[0051] Exemplarily, using the Zhukauskas correlation to calculate the shell-side heat transfer coefficient h s includes the following calculation method:

[0052] If 10 3 <Re s <2×10 5 :

[0053]

[0054] If 2×10 5 <Re s <2×10 6 :

[0055]

[0056] On the other hand, the heat transfer coefficient h on the tube side can be calculated using the following Gnielinski formula t :

[0057]

[0058] f t =(1.8lgRe t -1.5) -2 .

[0059] The following gives a preferred formula for obtaining the heat transfer coefficient h(i, j, k) in this embodiment

[0060]

[0061] where λ δ is the wall thermal conductivity of the heat transfer tube 230, r t , r s are the fouling thermal resistances of the inner and outer walls of the heat transfer tube 230 respectively, δ t is the wall thickness of the heat transfer tube 230, d0 and d t are the outer diameter and inner diameter of the heat transfer tube 230 respectively

[0062] On the basis of obtaining the heat transfer area a(i, j, k) and the heat transfer coefficient h(i, j, k), the following method is preferably used in this application to calculate the heat transfer temperature difference Δt(i, j, k)

[0063] Δt(i, j, k)=t s (i, j, k)-t t (i, j, k),

[0064] where t s and t t are the shell side temperature and tube side temperature of any heat transfer unit R(i, j, k) in the shell and tube heat exchanger 20 respectively. Further specifically, for heat transfer without phase change, t s (i, j, k)- and t t (i, j, k) can refer to the empirical practices in the prior art and be obtained by linear interpolation according to the inlet and outlet temperatures of the shell and tube sides of the shell and tube heat exchanger 20 and in the flow direction of the shell and tube sides, or can also be obtained by other assumption-iteration methods, and this application does not limit this

[0065] It should be noted that the above gives when using such asFigures 2 - 4 Based on the spatial region division of the shell-and-tube heat exchanger in a three-dimensional space in the present application as shown, there are some formula calculation methods combined with or improved based on the prior art. However, the present application is not limited to the formula forms proposed above. Specifically, after adopting the three-dimensional space division method in the present application, when it is necessary to solve the heat transfer amount of each heat exchange unit R(i, j, k), it can be deduced and calculated based on the formula examples listed or given above in combination with other empirical formulas in the art. On the other hand, the above three-dimensional space division method and the solution forms of each formula can be combined with technical software. For example, it can be directly written into the existing design software for shell-and-tube heat exchangers, so as to directly obtain the design conclusion of the shell-and-tube heat exchanger based on the heat transfer amount generation method proposed in the present application.

[0066] An embodiment of the present application also proposes a Figure 5 heat transfer amount generation system 50 of the shell-and-tube heat exchanger as shown. According to Figure 5 , the heat transfer amount generation system 50 of the shell-and-tube heat exchanger may include an internal communication bus 51, a processor 52, a read-only memory (ROM) 53, a random access memory (RAM) 54, and a communication port 55. When applied to a personal computer, the heat transfer amount generation system 50 of the shell-and-tube heat exchanger may further include a hard disk 56.

[0067] The internal communication bus 51 can realize data communication between the components of the heat transfer amount generation system 50 of the shell-and-tube heat exchanger. The processor 52 can make judgments and issue prompts. In some embodiments, the processor 52 may be composed of one or more processors. The communication port 55 can realize data communication between the heat transfer amount generation system 50 of the shell-and-tube heat exchanger and the outside. In some embodiments, the heat transfer amount generation system 50 of the shell-and-tube heat exchanger can send and receive information and data from the network through the communication port 55.

[0068] The heat transfer amount generation system 50 of the shell-and-tube heat exchanger may further include program storage units and data storage units in different forms, such as a hard disk 56, a read-only memory (ROM) 53, and a random access memory (RAM) 54, which can store various data files used for computer processing and / or communication, as well as possible program instructions executed by the processor 52. The processor executes these instructions to implement the main part of the method. The results processed by the processor are transmitted to the user device through the communication port and displayed on the user interface.

[0069] In addition, on the other hand, the present application also proposes a computer-readable medium storing computer program code, and the computer program code realizes the above-mentioned heat transfer amount generation method of the shell-and-tube heat exchanger when executed by a processor.

[0070] The basic concepts have been described above. Obviously, for those skilled in the art, the above application disclosure is only for illustration and does not constitute a limitation to this application. Although not explicitly stated here, those skilled in the art may make various modifications, improvements, and corrections to this application. Such modifications, improvements, and corrections are suggested in this application, so such modifications, improvements, and corrections still fall within the spirit and scope of the exemplary embodiments of this application.

[0071] Meanwhile, this application uses specific terms to describe the embodiments of this application. Such as "one embodiment", "an embodiment", and / or "some embodiments" mean a certain feature, structure, or characteristic related to at least one embodiment of this application. Therefore, it should be emphasized and noted that the "one embodiment" or "an embodiment" or "an alternative embodiment" mentioned twice or more at different positions in this specification does not necessarily refer to the same embodiment. In addition, certain features, structures, or characteristics in one or more embodiments of this application can be appropriately combined.

[0072] Some aspects of this application can be executed entirely by hardware, can be executed entirely by software (including firmware, resident software, microcode, etc.), or can be executed by a combination of hardware and software. The above hardware or software can all be referred to as "data blocks", "modules", "engines", "units", "components", or "systems". The processor can be one or more application specific integrated circuits (ASICs), digital signal processors (DSPs), digital signal processing devices (DAPDs), programmable logic devices (PLDs), field programmable gate arrays (FPGAs), processors, controllers, microcontrollers, microprocessors, or combinations thereof. In addition, aspects of this application may be embodied as a computer product located in one or more computer-readable media, which includes computer-readable program code. For example, computer-readable media can include, but are not limited to, magnetic storage devices (such as hard disks, floppy disks, magnetic tapes...), optical disks (such as compact disks CD, digital versatile disks DVD...), smart cards, and flash memory devices (such as cards, sticks, key drives...).

[0073] The computer-readable media may contain a propagated data signal having computer program code therein, for example, on a baseband or as part of a carrier wave. The propagated signal may have various forms of representation, including electromagnetic form, optical form, etc., or a suitable combination thereof. The computer-readable media can be any computer-readable media other than a computer-readable storage media, which can be connected to an instruction execution system, apparatus, or device to implement communication, propagation, or transmission for use of the program. The program code located on the computer-readable media can be propagated through any suitable media, including radio, cable, fiber optic cable, radio frequency signal, or similar media, or any combination of the above media.

[0074] Similarly, it should be noted that, in order to simplify the presentation of the disclosure of the present application and thus assist in the understanding of one or more embodiments of the application, in the foregoing description of the embodiments of the present application, various features are sometimes grouped together into one embodiment, drawing, or description thereof. However, this method of disclosure does not mean that the features required by the subject matter of the present application are more than those mentioned in the claims. In fact, the features of the embodiments are fewer than all the features of the individual embodiments disclosed above.

[0075] In some embodiments, numbers are used to describe components and the quantity of attributes. It should be understood that such numbers used in the description of embodiments are modified by the modifiers "about", "approximately", or "substantially" in some examples. Unless otherwise specified, "about", "approximately", or "substantially" indicate that the said numbers allow a variation of ±20%. Accordingly, in some embodiments, the numerical parameters used in the specification and claims are approximate values, and such approximate values may vary according to the characteristics required by individual embodiments. In some embodiments, the numerical parameters should consider the specified significant digits and adopt the method of retaining the general number of digits. Although the numerical ranges and parameters used in some embodiments of the present application to confirm the breadth of their scope are approximate values, in specific embodiments, such numerical settings are made as precise as possible within the feasible range.

[0076] Although the present application has been described with reference to the current specific embodiments, those of ordinary skill in the art in the technical field of the present application should recognize that the above embodiments are only used to illustrate the present application, and various equivalent changes or substitutions can be made without departing from the spirit of the present application. Therefore, as long as the changes and modifications to the above embodiments are within the scope of the spirit of the present application, they will fall within the scope of the claims of the present application.

Claims

1. A method for generating heat transfer amount of a shell-and-tube heat exchanger, the shell-and-tube heat exchanger comprising a shell, shell-side and tube-side inlet and outlet nozzles, and a tube bundle composed of a plurality of heat transfer tubes, an internal space of the tube bundle forming a tube side of the shell-and-tube heat exchanger, and a space between the tube bundle and the shell forming a shell side of the shell-and-tube heat exchanger, characterized in that, The method includes the following steps: Establish an o-xyz three-dimensional coordinate system for the shell-and-tube heat exchanger, and obtain a first regional division plan view generated according to the yoz plane and a second regional division plan view generated according to the xoz plane; Locate any heat exchange unit R(i, j, k) according to the first regional division plan view and the second regional division plan view, where i, j, and k respectively correspond to the positions of the any heat exchange unit R(i, j, k) in the yoz plane, the xoz plane, and the xoy plane; Obtain the heat transfer coefficient h(i, j, k), the heat transfer area a(i, j, k), and the heat transfer temperature difference Δt(i, j, k) for the any heat exchange unit R(i, j, k); and Calculate and generate the heat transfer amount of the any heat exchange unit R(i, j, k) using the following formula: wherein, the method further includes calculating and obtaining the heat transfer area a(i, j, k) through the following formula: where n is the uniform distribution density of the tube bundle in the xoz plane, N s is the number of layers of the shell side divided along the y-axis direction, S is the cross-sectional area of the shell in the xoz plane, A is the total heat transfer area of the outer surface of the tube bundle, and s(i, k) is the cross-sectional area of the heat transfer unit of any heat transfer unit R(i, j, k) in the xoz plane. In addition, the method further includes calculating the tube-side heat transfer coefficient h corresponding to the tube pass in the shell-and-tube heat exchanger t , the shell-side heat transfer coefficient h corresponding to the shell pass s and the tube wall thermal resistance, so as to calculate the heat transfer coefficient h(i, j, k) corresponding to any heat exchange unit R(i, j, k) according to the tube-side heat transfer coefficient h t , the shell-side heat transfer coefficient h s and the tube wall thermal resistance through the following formula: Among them, λ δ is the wall thermal conductivity of the heat transfer tube, r t , r s are the fouling thermal resistances of the inner and outer walls of the heat transfer tube respectively, δ t is the wall thickness of the heat transfer tube, d0 and d t are the outer diameter and inner diameter of the heat transfer tube respectively.

2. The method according to claim 1, characterized in that It further includes respectively calibrating the shell-side inlet, the shell-side outlet, the tube-side inlet, and the tube-side outlet in the first regional division plan view according to the positions of the shell-and-tube process inlet and outlet nozzles, and calibrating a plurality of shell-side division planes parallel to the xoz plane and arranged along the y-axis direction, a plurality of tube-side division planes parallel to the xoy plane and arranged along the z-axis direction, and a plurality of shell longitudinal division planes parallel to the yoz plane and arranged along the x-axis direction in the first regional division plan view and the second regional division plan view, wherein, A plurality of the shell-side division layers are formed between every two adjacent shell-side division planes or between the shell-side division plane and the boundary of the shell-side; A plurality of tube-side division layers are formed between every two adjacent tube-side division planes or between the tube-side division plane and the boundary of the tube-side; A plurality of shell longitudinal division layers are formed between every two adjacent shell longitudinal division planes or between the shell longitudinal division plane and the boundary of the shell; and The i, j, and k respectively represent the shell longitudinal division layer, the shell-side division layer, and the tube-side division layer where the any heat exchange unit R(i, j, k) is located.

3. The method according to claim 2, characterized in that, It further includes setting the positions of the plurality of shell-side division planes to be consistent with the positions of the baffles inside the shell-and-tube heat exchanger.

4. The method according to claim 2 or 3, characterized in that, It further includes defining a starting heat exchange unit R(1, 1, 1), and obtaining the values of i, j, and k according to the relative position relationship between any other heat exchange unit R(i, j, k) and the starting heat exchange unit R(1, 1, 1) inside the shell-and-tube heat exchanger, where the starting heat exchange unit R(1, 1, 1) is the unit closest to the origin of coordinates in the xoz plane in the shell longitudinal division layer where the shell-side inlet is located.

5. The method according to claim 1, characterized in that, It also includes calculating the shell-side heat transfer coefficient h using the Zhukauskas correlation s , and calculating the tube-side heat transfer coefficient h using the Gnielinski formula t .

6. The method according to claim 1, wherein The heat transfer temperature difference Δt(i, j, k) is obtained through the following manner: Δt(i, j, k) = t s (i, j, k) - t t (i, j, k), where t s and t t are respectively the shell-side temperature and the tube-side temperature of any heat exchange unit R(i, j, k) in the shell-and-tube heat exchanger.

7. The method according to claim 1, wherein The shell-and-tube heat exchanger includes a single-pass shell structure or a double-pass shell structure with a longitudinal baffle.

8. A heat transfer amount generation system for a shell-and-tube heat exchanger, comprising: A memory for storing instructions executable by a processor; And a processor for executing the instructions to implement the method according to any one of claims 1-7.

9. A computer-readable medium storing computer program code, which when executed by a processor implements the method according to any one of claims 1-7.

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