A flow commissioning method and system for a ship cooling water system

Abstract

The application discloses a flow debugging method and system for a ship cooling water system, and the flow debugging method comprises the following steps: constructing a pipe network model of the ship cooling water; setting data parameters of each component in the pipe network model and fluid parameters in the pipe network; calculating a first flow value and a turbulence intensity value; obtaining a suitable valve opening degree by judging the turbulence intensity value and the flow value; applying the valve opening degree to an actual ship pipe system; judging an error value of an actual flow and a model flow; and determining a final execution valve opening degree. Furthermore, the application can realize reasonable distribution of the flow of the cooling water system, realize high-accuracy flow debugging, and avoid causing insufficient cooling or excessive cooling of mechanical equipment.

Description

Technical Field

[0001] This invention relates to the field of marine pipeline flow control technology, specifically to a flow control method and system for marine cooling water systems. Background Technology

[0002] Piping systems are a crucial component of ships. Among them, the ship's cooling water system provides cooling water for the entire vessel, removing excess and harmful heat generated during equipment operation to ensure normal equipment function. Mechanical equipment requiring cooling in the system includes main and auxiliary diesel engines, oil coolers, freshwater coolers, shaft bearings, air compressors, condensers, and air conditioners, with the main engine dissipating the largest amount of heat. Therefore, ship cooling water systems are typically centered around the main engine's cooling piping, and are composed of cooling piping for other mechanical equipment and various auxiliary cooling devices, resulting in numerous components and a complex piping network.

[0003] The heat dissipation requirements of various devices in a cooling water system often differ. Therefore, when determining the cooling water flow distribution, the consequences of insufficient or excessive cooling must be fully considered. Taking the engine as an example, insufficient cooling will cause components to overheat, leading to a decline in material mechanical properties, thermal stress and deformation, resulting in excessive wear or even seizure and damage. Conversely, excessive cooling will cause the cooling water to remove too much heat, thus reducing the engine's fuel economy. When using fuels with high sulfur content, excessive cooling will cause sulfuric acid to form inside the cylinder, corroding the cylinder walls and piston. Therefore, the rational distribution of the cooling water flow is extremely important.

[0004] Currently, published patents on flow control in pipeline systems mainly focus on water supply and drainage networks, ventilation networks, heating networks, and liquid cooling networks. For example, invention patent CN102278598B provides a test method for flow distribution in large-scale pipeline networks. By calibrating the flow resistance characteristic curves of each ventilation branch in the pipeline network, the ventilation branch with the largest flow resistance and the nearest branch are opened in sequence. Flow-limiting rings are gradually installed at the ventilation openings of each branch to control the flow resistance of each branch to the flow resistance under the design ventilation flow rate, thereby completing the distribution of pipeline network flow.

[0005] Given the extensive use of valves in actual cooling water systems, efficient cooling water regulation can be translated into the rational setting of valves. However, ship cooling water system valves typically only have two states: open and closed. During system operation, when the open and closed states of the valves cannot meet the flow requirements of the piping system, orifice plates are generally used to regulate pressure, thereby regulating the flow in the corresponding pipeline to avoid excessive flow inside the equipment. Therefore, cooling water distribution further translates into the setting of orifice plate geometry.

[0006] During on-site commissioning, due to the complexity of the pipeline network, when the valves are fully open, the orifice plate's structure is fixed after installation. The orifice diameter can only be adjusted by continuously replacing the orifice plate or modifying its structure on-site to achieve the required pipeline flow rate. This adjustment process requires repeated iterations, is difficult and time-consuming, and often results in the orifice plate becoming unusable due to improper orifice diameter adjustment, leading to significant waste of manpower and materials. Therefore, there is an urgent need for a high-precision optimization design and commissioning method for ship cooling systems, allowing flow rate commissioning to be performed during the pipeline network design phase. Summary of the Invention

[0007] In view of the shortcomings of the prior art described above, the purpose of this invention is to provide a flow rate adjustment method and system for ship cooling water systems, so as to achieve reasonable distribution of the flow rate of the cooling water system, achieve high-accuracy flow rate adjustment, and avoid insufficient or excessive cooling of mechanical equipment.

[0008] To achieve the above and other related objectives, the present invention provides a method for adjusting the flow rate of a ship's cooling water system, comprising:

[0009] S1: Construct a pipe network model of the ship's cooling water system. The pipe network model includes various components, including pipes and valves.

[0010] S2: Set the data parameters of each component in the pipeline model and the fluid parameters in the pipeline, and set the resistance coefficient of the valve to the minimum. At this time, the resistance coefficient of the valve is the first valve resistance coefficient.

[0011] S3: Based on the set values ​​of data parameters, fluid parameters, first valve resistance coefficient, and the relationship curve between resistance coefficient and Reynolds number when the valve is fully open, calculate the first flow rate and turbulence intensity value in each section of the pipeline.

[0012] S4: Compare the turbulence intensity value with the preset turbulence intensity range to determine whether the turbulence intensity value is within the preset turbulence intensity range;

[0013] S5: Compare the first flow rate value corresponding to the turbulence intensity value within the preset turbulence intensity range with the first preset flow rate range to determine whether the first flow rate value is within the first preset flow rate range, and obtain the second valve resistance coefficient of each valve based on the first flow rate value within the first preset flow rate range;

[0014] S6: Obtain the first valve opening based on the resistance coefficient-valve opening curve and the second valve resistance coefficient;

[0015] S7: Apply the first valve opening to the actual ship pipeline system to obtain the flow rate value in the actual ship pipeline system, and record it as the third flow rate value;

[0016] S8: Calculate the error between the third flow rate value and the model flow rate value corresponding to the first valve opening, and determine whether the error value is within the preset error range;

[0017] S9: Take the valve opening corresponding to the third flow value within the preset error range as the final valve opening, or continue to determine whether the third flow value is within the second preset flow range, and take the valve opening corresponding to the third flow value within the second preset flow range as the final valve opening.

[0018] Optionally, the step of determining whether the turbulence intensity value is within a preset turbulence intensity range includes:

[0019] When the turbulence intensity value is within the preset turbulence intensity range, proceed to step S5;

[0020] When the turbulence intensity value is not within the preset turbulence intensity range, the pipe segment in the pipeline network model is adjusted, and the process returns to step S1.

[0021] Optionally, the step of determining whether the first flow rate value is within the first preset flow rate range includes:

[0022] When the first flow rate value is within the first preset flow rate range, the first valve resistance coefficient is the second valve resistance coefficient;

[0023] When the second flow rate value is not within the first preset flow rate range, the flow rate value of each pipeline is set within the first preset flow rate range, and the flow rate value set within the first preset flow rate range is defined as the second flow rate value. The second valve resistance coefficient of each valve is calculated based on the second flow rate value.

[0024] Optionally, the step of calculating the second valve resistance coefficient for each valve based on the second flow rate value includes:

[0025] If the trial calculation is successful, the resistance coefficient of each valve that is successfully solved is the second valve resistance coefficient obtained for each valve.

[0026] If the trial calculation fails, the pipeline system of the pipeline network model needs to be adjusted, and steps S1 to S5 are repeated until the second valve resistance coefficient of each valve is obtained.

[0027] Optionally, the step of determining whether the error value is within a preset error range further includes:

[0028] When the error value is within the preset error range, proceed to step S9;

[0029] When the error value is outside the error range, the data parameters of the pipelines, valves and other components in the pipeline network model are corrected, and steps S1 to S8 are repeated until the error value is within the preset error range.

[0030] Optionally, the step of determining whether the third flow value is within the second preset flow range includes:

[0031] If the third flow rate value is within the second preset flow rate range, then the valve opening corresponding to the third flow rate value at this time is the final valve opening.

[0032] If the third flow rate value is not within the second preset flow rate range, the pipe segment in the pipeline network model is adjusted, and the process returns to step S1 until the third flow rate value is within the second preset flow rate range. The valve opening at this point is then used as the final valve opening.

[0033] Optionally, after determining the final valve opening, the following steps are also included:

[0034] In the actual ship piping system, the final valve opening is executed, and the actual resistance coefficient is obtained and recorded as the third valve resistance coefficient. At the same time, the Reynolds value is obtained.

[0035] The resistance coefficient-valve opening-Reynolds number curve is corrected based on the final valve opening, the third valve resistance coefficient, and the Reynolds number.

[0036] Optionally, the step of performing the final valve opening in the actual ship piping system and obtaining the third valve resistance coefficient includes:

[0037] The resistance coefficient of the throttling orifice plate is calculated based on the resistance coefficient of the third valve and the resistance coefficient of the first valve.

[0038] Calculate the orifice diameter parameters of the orifice plate based on its resistance coefficient;

[0039] The final valve opening is determined by adjusting the orifice diameter parameters of the throttling orifice plate in the actual ship's piping system.

[0040] Optionally, the step of obtaining the third valve resistance coefficient includes:

[0041] The resistance coefficient of the third valve is calculated by using the differential pressure readings of pressure sensors installed in the actual ship's piping system.

[0042] Optionally, after correcting the resistance coefficient-valve opening-Reynolds number curve, the following is also included:

[0043] The fourth valve resistance coefficient for each valve at the corresponding valve opening is calculated using the modified resistance coefficient-valve opening-Reynolds numerical curve.

[0044] The resistance coefficient of the throttling orifice plate is calculated based on the resistance coefficient of the fourth valve and the resistance coefficient of the first valve.

[0045] Calculate the orifice diameter parameters of the orifice plate based on its resistance coefficient;

[0046] The orifice diameter of the orifice plate in the actual ship piping system is inspected and corrected based on the orifice diameter parameters of the orifice plate.

[0047] The present invention also provides a flow debugging system, comprising:

[0048] The pipeline model building module is used to build a pipeline model based on the actual ship pipeline system.

[0049] The data parameter setting module is used to set the data parameters of various components in the pipeline network model and the fluid parameters in the pipeline network, and to set the resistance coefficient of the valve to the minimum. At this time, the resistance coefficient of the valve is the first valve resistance coefficient.

[0050] The calculation module is used to calculate the first flow rate and turbulence intensity value in each section of the pipeline based on data parameters, fluid parameters and the first valve resistance coefficient;

[0051] The first comparison and judgment module is used to compare the turbulence intensity value with a preset turbulence intensity range to determine whether the turbulence intensity value is within the preset turbulence intensity range; and to compare the first flow rate value corresponding to the turbulence intensity value within the preset turbulence intensity range with the first preset flow rate range to determine whether the first flow rate value is within the first preset flow rate range; and to obtain the second valve resistance coefficient of each valve based on the first flow rate value within the first preset flow rate range.

[0052] The valve opening calculation module is used to obtain the first valve opening based on the resistance coefficient-valve opening curve and the second valve resistance coefficient.

[0053] The error calculation module is used to obtain the error value between the third flow rate value and the model flow rate value corresponding to the first valve opening.

[0054] The second comparison and judgment module is used to determine whether the error value is within the preset error range. When the third flow value is within the preset error range, it determines whether the third flow value is within the second preset flow range. The valve opening corresponding to the third flow value within the second preset flow range is used as the final valve opening.

[0055] Optionally, the first comparison and judgment module also includes:

[0056] The turbulence intensity comparison and judgment module is used to compare the turbulence intensity value with a preset turbulence intensity range to determine whether the turbulence intensity value is within the preset turbulence intensity range.

[0057] The flow rate comparison and judgment module compares the first flow rate value corresponding to the turbulence intensity value within the preset turbulence intensity range with the first preset flow rate range to determine whether the first flow rate value is within the first preset flow rate range, and obtains the second valve resistance coefficient of each valve based on the first flow rate value within the first preset flow rate range.

[0058] In the trial calculation module, when the flow comparison and judgment module determines that the first flow value is not within the first preset flow range, the trial calculation module sets the flow value of each pipeline within the first preset flow range, defines the flow value set within the first preset flow range as the second flow value, and calculates the second valve resistance coefficient of each valve based on the second flow value.

[0059] Optionally, the flow debugging system also includes:

[0060] The drag coefficient-valve opening-Reynolds number curve correction module is used to correct the drag coefficient-valve opening-Reynolds number curve based on the third valve drag coefficient, the final valve opening and Reynolds number obtained when the final valve opening is executed in the actual ship piping system.

[0061] The orifice plate diameter parameter calculation module is used to calculate the resistance coefficient of the fourth valve based on the corrected resistance coefficient-valve opening-Reynolds number curve correction module, calculate the resistance coefficient of the orifice plate based on the resistance coefficient of the fourth valve and the resistance coefficient of the first valve, and then calculate the orifice plate diameter parameter based on the resistance coefficient of the orifice plate.

[0062] Compared with the prior art, the flow rate adjustment method and system for ship cooling water systems described in this invention have at least the following beneficial effects:

[0063] Compared to engineering practice, there are relatively few patents currently available regarding the flow distribution and commissioning of ship cooling water systems. Furthermore, most pipe network simulations use table lookup methods to obtain the resistance coefficient when valves are fully open. Taking a gate valve as an example, its resistance coefficient when fully open is shown in Table 1, but the correspondence between valve opening, flow state, and resistance coefficient is unknown. For the refined design and simulation of ship cooling systems, the influence of both valve opening and flow state on the valve resistance coefficient must be considered simultaneously. This allows reliable pipe network simulation results to be combined with orifice plate design, providing guidance for the design and commissioning of the cooling system.

[0064] The flow rate commissioning method described in this invention can perform high-precision flow rate commissioning during the design phase of a ship's cooling water system pipeline network, ensuring that each pipeline meets the flow rate requirements, correcting the flow resistance coefficient / valve opening / Reynolds number curves, solving for the valve opening and resistance coefficients, and outputting the orifice diameter parameters of the throttling plate. This provides guidance for subsequent on-site commissioning and has significant advantages in promoting high-precision commissioning, providing optimized design schemes for cooling water pipeline networks, and reducing labor and material costs.

[0065] The flow rate debugging system described in this invention, when applied to the above-mentioned method, also achieves the aforementioned technical effects. Attached Figure Description

[0066] Figure 1 This is a flowchart of the flow rate adjustment method for a ship cooling water system as described in an embodiment of the present invention;

[0067] Figure 2 This is a diagram illustrating the operation steps of the flow rate adjustment method for a ship cooling water system as described in this embodiment of the invention.

[0068] Figure 3a This is a graph showing the variation of the resistance coefficient with the flow regime (Reynolds number Re) in the pipe when the valve is fully open, according to an embodiment of the present invention.

[0069] Figure 3b This is a graph showing the variation of valve resistance coefficient with Reynolds number and valve opening degree in an embodiment of the present invention;

[0070] Figure 4 This is a schematic diagram of the throttling orifice plate in an embodiment of the present invention;

[0071] Figure 5 This is a loop execution in the embodiments of the present invention. Figure 2 The diagram shows the optimization steps following the steps shown.

[0072] Figure 6 This is a schematic diagram of a flow rate adjustment system for a ship's cooling water system, as described in an embodiment of the present invention.

[0073] List of reference numerals in the attached diagram:

[0074] 1 pipe

[0075] 2 orifice plates

[0076] 3-orifice plate Detailed Implementation

[0077] The following specific embodiments illustrate the implementation of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of this application. It should be noted that, unless otherwise specified, the following embodiments and features in the embodiments can be combined with each other.

[0078] It should be understood that the illustrations provided in the embodiments of this invention are merely schematic representations of the basic concept of the invention. Although the illustrations only show components relevant to the invention and are not drawn according to the actual number, shape, and size of components in implementation, the shape, quantity, and proportion of each component can be arbitrarily changed in actual implementation, and the component layout may also be more complex. The structures, proportions, sizes, etc., shown in the accompanying drawings are only used to complement the content disclosed in the specification for those skilled in the art to understand and read, and are not intended to limit the conditions under which this application can be implemented. Therefore, they have no substantial technical significance. Any modifications to the structure, changes in the proportional relationships, or adjustments to the size, without affecting the effects and objectives that the invention can produce, should still fall within the scope of the technical content disclosed in this application.

[0079] This embodiment provides a method for adjusting the flow rate of a ship's cooling water system, referring to... Figure 1 The traffic debugging method includes the following steps:

[0080] S1: Construct a pipe network model of the ship's cooling water system. The pipe network model includes various components, including pipes and valves.

[0081] Specifically, a pipe network model of the ship's cooling water system is constructed. This model includes various components, primarily the pipes, pipe fittings (valves, tees, elbows, reducers, etc.), and various equipment. Simultaneously, the boundary conditions of the pipe network need to be acquired and set, mainly referring to pressure or velocity boundaries.

[0082] S2: Set the data parameters of each component in the pipeline model and the fluid parameters in the pipeline, and set the resistance coefficient of the valve to the minimum. At this time, the resistance coefficient of the valve is the first valve resistance coefficient.

[0083] Specifically, refer to Figure 2 Set the parameters of each component and fluid within the pipeline network model, mainly including pipeline and pipe fitting parameters, equipment inlet and outlet parameters, pump performance curves, and fluid parameters (density, temperature, and pressure) within the pipes.

[0084] Reference Figure 2 All valves in the pipeline model are set to fully open to minimize the resistance coefficient of each valve, and this minimum resistance coefficient is recorded as the first valve resistance coefficient. Specific values ​​can be retrieved through the program or obtained from Table 1.

[0085] Table 1. Minimum resistance coefficients for gate valves, check valves, and globe valves.

[0086]

[0087] The minimum resistance coefficient of a butterfly valve can be calculated. The calculation method for the minimum resistance coefficient of a butterfly valve is shown in formula (1):

[0088]

[0089] In formula (1):

[0090] ξ—Minimum resistance coefficient of the butterfly valve;

[0091] g — acceleration due to gravity (9.81 m / s²) 2 );

[0092] P2—Local resistance loss head (Pa);

[0093] V – Flow velocity (m / s).

[0094] S3: Calculate the first flow rate and turbulence intensity value in each pipeline section based on the data parameters, fluid parameter settings, and first valve resistance coefficient;

[0095] Based on steps S1 and S2, the data parameters of each component and the resistance coefficient of the first valve are obtained. The data parameters of each component include pump parameters (characteristic curve fitting), pipe diameter, pipe roughness, and inlet / outlet boundary parameters. The valve is set to the fully open state. Considering the influence of the internal flow state on the valve resistance, the curve showing the relationship between the resistance coefficient and the Reynolds number Re (characterizing the flow state inside the pipe) when the valve is fully open is obtained, such as... Figure 3a As shown, it should be noted that the curve showing the relationship between the resistance coefficient and the Reynolds number Re when the valve is fully open is obtained based on existing experience. Furthermore, a curve showing the relationship between the resistance coefficient and the Reynolds number Re (characterizing the flow state within the pipe) when the valve is fully open is fitted. This relationship is then imported into commercial pipeline software such as Applied Flow Technology and Flomaster, or iteratively solved using proprietary simulation software to obtain the flow rate Q for each pipeline segment. This flow rate value is recorded as the first flow rate value. Additionally, the transient flow calculation module in the pipeline software is used to obtain the turbulence intensity value I of the fluid in each pipe fitting, thereby obtaining the turbulence intensity value for the entire pipeline network.

[0096] S4: Compare the turbulence intensity value with the preset turbulence intensity range to determine whether the turbulence intensity value is within the preset turbulence intensity range;

[0097] The turbulence intensity value is compared with a preset turbulence intensity range. In this embodiment, the preset turbulence intensity range is I ≤ 1%. The value of the turbulence intensity range I will affect whether there is vibration inside the pipeline network to a certain extent. Excessive pipeline network vibration will affect the service life of the pipeline system. Therefore, this embodiment also judges the vibration state inside the pipeline network to ensure that the pipeline network vibration is small and to increase the service life of the pipeline system. If the turbulence intensity value I of the pipe section is ≤ 1%, it can be judged that there is no vibration inside the pipeline network; if there is a turbulence intensity value I > 1% in some pipe sections, there is a possibility of pipeline vibration, and the corresponding pipe sections should be adjusted. Specifically, pipeline system adjustment includes, but is not limited to, corresponding pipe diameter adjustment, pipeline route adjustment, and replacement of accessories such as pumps, etc., and then repeating steps S1 to S4.

[0098] S5: Compare the first flow rate value corresponding to the turbulence intensity value within the preset turbulence intensity range with the first preset flow rate range to determine whether the first flow rate value is within the first preset flow rate range, and obtain the second valve resistance coefficient of each valve based on the first flow rate value within the first preset flow rate range;

[0099] The first flow rate value corresponding to the turbulence intensity value being within the preset turbulence intensity range is compared with the first preset flow rate range to determine whether the first flow rate value is within the first preset flow rate range. In this embodiment, refer to... Figure 2 The first preset flow rate range is between 2Q. req >Q>1.2Q req Where Q is the actual flow rate, Q req This represents the traffic demand value.

[0100] When determining whether the first flow rate value is within the first preset flow rate range, if the first flow rate value is within the first preset flow rate range, the first valve resistance coefficient can be used as the second valve resistance coefficient. If the first flow rate value is not within the first preset flow rate range, the flow rate value of each pipeline is set within the first preset flow rate range, and the flow rate value set within the first preset flow rate range is defined as the second flow rate value. The second valve resistance coefficient of each valve is calculated based on the second flow rate value. If the calculation is successful, the resistance coefficient of each valve that is successfully calculated is the obtained second valve resistance coefficient of each valve. If the calculation fails, the pipeline system of the pipeline network model needs to be adjusted, and steps S1 to S5 are repeated until the second valve resistance coefficient of each valve is obtained. Specifically, the resistance coefficient of each pipeline valve is set as the independent variable, with its minimum value being the resistance coefficient when the valve is fully open and its maximum value being set to 80. The flow rate of each pipeline segment (i.e., the target variable) is set to 2Q. req >Q>1.2Q reqThen, the resistance coefficient of each valve is calculated. If the valve adjustment is successful (i.e., the resistance coefficient of each pipeline is successfully calculated), the corresponding valve resistance coefficient is recorded as the second valve resistance coefficient. When the valve adjustment fails (the calculation fails), the pipeline system needs to be adjusted, including but not limited to adjusting the corresponding pipe diameter, adjusting the pipeline route, and replacing accessories such as pumps. Furthermore, existing commercial software can be used for trial calculations. When the flow rate Q in the pipeline exceeds 2Q... req When this happens, the opening of one or more valves needs to be reduced, and the Q value needs to be recalculated through trial and error or iteration. The goal is to obtain Q values ​​that are 1.2-2 times the required Q value. req If the flow rate does not reach the first preset flow range regardless of the valve opening adjustment, then the pipeline system needs to be adjusted, and steps S1 to S5 need to be repeated until the flow rate Q reaches the first preset flow range, thereby obtaining the second valve resistance coefficient for each valve.

[0101] S6: Obtain the first valve opening based on the resistance coefficient-valve opening curve and the second valve resistance coefficient.

[0102] In step S4, the second valve resistance coefficient of each valve is obtained, and the first valve opening is obtained based on the existing resistance coefficient-valve opening curve. If the corresponding valve opening cannot be found through the curve, the corresponding pipeline needs to be adjusted. Specifically, pipeline system adjustments include, but are not limited to, corresponding pipe diameter adjustments, pipeline route adjustments, and replacement of accessories such as pumps, etc., and then step S1 is repeated.

[0103] S7: Apply the first valve opening to the actual ship pipeline system to obtain the flow rate value in the actual ship pipeline system, and record it as the third flow rate value;

[0104] Reference Figure 2 The system executes the first valve opening output and adjusts the valve opening on-site. When the on-site valve has an opening indication, it is adjusted according to the valve opening (0-100%) output by simulation calculation. When there is no opening indication, for ease of on-site operation, debugging guidance is provided for 1 / 4 opening, 1 / 2 opening, 3 / 4 opening, and fully open. In the on-site debugging process of this embodiment, the orifice diameter of the throttling orifice plate is used to equivalently simulate the valve opening in the pipeline network model. Furthermore, during the execution of the first valve opening or other valve openings, the orifice diameter parameter of the throttling orifice plate under the valve opening can be calculated by the correspondence between the valve resistance coefficient corresponding to the valve opening and the resistance coefficient of the throttling orifice plate, thereby realizing the execution of the first valve opening or other valve openings.

[0105] The calculation method for local resistance in a one-dimensional pipeline is shown in formula (2):

[0106] ξa =ξ+ξ orifice (2)

[0107] In formula (2):

[0108] ξ a — Valve resistance coefficient with opening degree, where 'a' represents the valve opening degree: 0-100% opening degree (or: 1 / 4 opening degree, 1 / 2 opening degree, 3 / 4 opening degree, and fully open);

[0109] ξ—Valve resistance coefficient when fully open;

[0110] ξ orifice — Corresponding resistance coefficient of the orifice plate.

[0111] Based on the resistance coefficient of the fourth valve, the resistance coefficient of the corresponding orifice plate in the pipeline is obtained, thereby calculating and outputting the orifice plate diameter parameters. Due to space limitations, only an angled orifice plate is used as an example here, its structure as follows: Figure 4 As shown. (Refer to...) Figure 4 In the figure, the orifice plate 2 is installed inside the pipe 1, and the orifice plate 3 is provided on the upper part of the orifice plate 2. The relationship between the resistance coefficient and the parameters of the orifice plate is shown in formula (3):

[0112]

[0113] In formula (3):

[0114] ξ orifice —Drag coefficient;

[0115] A up —Cross-sectional area of ​​the pipe upstream of the throttling orifice plate;

[0116] A down —Cross-sectional area of ​​the pipe downstream of the orifice plate;

[0117] A orifice —Orifice area of ​​the throttling plate.

[0118] Among them, A up and A down The parameters are known.

[0119] It should be noted that orifice plates also include various types, such as those with changes in area between upstream and downstream, and those with smooth transitions. The corresponding formulas can be used to solve the problem.

[0120] Reference Figure 2 After the valve opening is adjusted, the actual flow rate Q of the corresponding pipe section is read and recorded. r The actual traffic value Q r This is recorded as the third flow value.

[0121] S8: Calculate the error between the third flow rate value and the model flow rate value corresponding to the first valve opening, and determine whether the error value is within the preset error range;

[0122] Reference Figure 2 Calculate the third flow value Q r The error value between the model flow rate value and the first valve opening degree.

[0123] In this embodiment, it is determined whether the error range is met. Q is the flow rate value corresponding to the pipeline model when the first valve opening is executed, that is, the first flow rate value or the second flow rate value; Q r This is the third flow rate value read from the actual ship's piping system. The determination is made as to whether the third flow rate value is within the preset error range.

[0124] S9: When the third flow value is within the preset error range, the valve opening corresponding to the third flow value within the preset error range is taken as the final valve opening. Alternatively, it is determined whether the third flow value is within the second preset flow range, and the valve opening corresponding to the third flow value within the second preset flow range is taken as the final valve opening.

[0125] In one embodiment, reference is made to Figure 2 When the error value is within the error range, the first valve opening is executed as the final valve opening, and data that meets the error range is entered into step ② for error analysis. When the error value is outside the error range, the data parameters of pipelines, valves, and other components in the pipeline network model are corrected, and steps S1 to S7 are re-executed until the error value is within the error range. The second valve opening is then obtained and used as the final valve opening. Data that does not meet the error range is entered into step ① for error analysis. The equipment parameters and fluid parameters in the calculation model are then corrected to obtain a new calculation model.

[0126] In another embodiment, reference is made to Figure 2 When the error value is within the error range, the data that meets the error range is entered ② for error analysis. Then, it is further determined whether the third flow rate value is within the second preset flow rate range. The valve opening corresponding to the third flow rate value within the second preset flow rate range is taken as the final valve opening. Specifically, the second preset flow rate range is Q. r <1.1Q req Q r Q is the third flow value. req This represents the traffic demand value. If Q... r >1.1Q reqThis indicates that the pipeline is prone to vibration and requires adjustments to the pipeline system, including but not limited to adjusting the corresponding pipe diameter, adjusting the pipeline route, replacing accessories such as pumps, and increasing the strength of supports. Then, return to execute S1. If Q r <1.1Q req The valve opening corresponding to the flow rate at that time will be the final valve opening. The flow rate range can affect the presence or absence of vibration within the pipeline network to some extent. Excessive pipeline vibration can affect the service life of the pipeline system. Therefore, this embodiment uses the flow rate range to determine the vibration state within the actual pipeline system, in order to ensure that the pipeline vibration is minimized and to increase the service life of the pipeline system.

[0127] Similarly, when the error value is outside the error range, the data parameters of the pipelines, valves, and other components in the pipeline network model are corrected, and steps S1 to S7 are re-executed until the error value is within the error range. The second valve opening is then obtained and used as the final valve opening. Data that does not meet the error range is entered ① for error analysis. The equipment and fluid parameters in the calculation model are then corrected to obtain a new calculation model.

[0128] In an optional embodiment of this example, after step S9, a step of correcting the resistance coefficient-valve opening-Reynolds number curve is further included. This step includes: executing the final valve opening in the actual ship piping system and obtaining the actual resistance coefficient, which is recorded as the third valve resistance coefficient; simultaneously, calculating the Reynolds number according to existing formulas. Based on the final valve opening, the third valve resistance coefficient, and the Reynolds number, the existing resistance coefficient-valve opening-Reynolds number curve is corrected. The third valve resistance coefficient is calculated using the differential pressure reading ΔP of the pressure sensor installed in the actual ship piping system. Furthermore, the relationship curve between valve opening, resistance coefficient, and Reynolds number is corrected and optimized, such as... Figure 3b As shown. It should be noted that, Figure 3a and Figure 3b The flow resistance coefficient and drag coefficient are the same concept; to avoid misunderstanding, this clarification is provided here. This can be determined according to the formula... The resistance coefficient of the third valve is solved, where ΔP is the pressure sensor reading, ρ is the fluid density, v is the flow velocity, and ξ is the resistance coefficient. Simultaneously, the actual Reynolds number is solved using the existing Reynolds number formula.

[0129] Optionally, after correcting the drag coefficient-valve opening-Reynolds number curve, the process also includes correcting the orifice plate parameters in the actual ship piping system. This step includes: calculating the fourth valve drag coefficient for each valve at its corresponding valve opening using the corrected drag coefficient-valve opening-Reynolds number curve; calculating the orifice plate drag coefficient based on the fourth valve drag coefficient and the first valve drag coefficient; calculating the orifice plate diameter parameters based on the orifice plate drag coefficient; and verifying and correcting the orifice plate diameter in the actual ship piping system based on the orifice plate diameter parameters.

[0130] Specifically, refer to Figure 2 Adopt the revised Figure 3b The resistance coefficient of each valve at its corresponding valve opening degree is solved using the curve to obtain the resistance coefficient of the fourth valve. The resistance coefficient of the fourth valve is then used to calculate and verify the parameters of the orifice plate. The orifice diameter parameters of the orifice plate are solved using the above formulas (2) and (3). After on-site commissioning, the orifice diameter parameters of the orifice plate are verified and corrected.

[0131] The above data was entered into data entry ③, and error analysis was performed by combining data entry ① and data entry ②. After long-term system operation, the data obtained from the analysis are shown in Tables 2-4.

[0132] Table 2 Confidence of Valid Outputs

[0133] Error range ≤2％ ≤5％ ≤8％ ≤20％ Confidence <![CDATA[X1]]> <![CDATA[X2]]> <![CDATA[X3]]> <![CDATA[X4]]>

[0134] Note: X1 = (Number of times with error value ≤ 2%) / (Number of times with error value ≤ 20%);

[0135] X2 = (Number of times with an error value ≤ 5%) / (Number of times with an error value ≤ 20%);

[0136] X3 = (Number of times with an error value ≤ 8%) / (Number of times with an error value ≤ 20%);

[0137] X4 = (Number of times with an error value ≤ 20%) / (Number of times with an error value ≤ 20%), X4 = 100%.

[0138] Table 3. Statistics of Flow Calculation Results Output

[0139] Output Effective (≤20%) Ineffective (>20%) Proportion <![CDATA[X5]]> <![CDATA[X6]]>

[0140] Note: X5 = Valid attempts / (Valid attempts + Invalid attempts);

[0141] X6 = Number of invalid attempts / (Number of valid attempts + Number of invalid attempts);

[0142] when It is considered valid when It is deemed invalid at that time.

[0143] Table 4. Statistical Analysis of Orifice Plate Calculation Results

[0144] Output ≤20％ ＞20％ Proportion <![CDATA[X7]]> <![CDATA[X8]]>

[0145] Note: X7 = Number of times the error value is less than or equal to 20% / Total number of times;

[0146] X8 = Number of times the error value is greater than 20% / Total number of times.

[0147] Based on the valid output confidence level and the calculated statistical results, the model can provide a basis for system reliability assessment and subsequent general optimization design. After extensive data collection and training, the model can achieve efficient and accurate commissioning of the pipeline system. It should be noted that the values ​​in the above scheme (e.g., the opening step values ​​for valves without opening indicators, and the flow error limit of 20%) are only illustrative and are not intended to limit their numerical range.

[0148] This embodiment also provides a flow debugging system, referencing... Figure 6 The flow rate adjustment system includes a pipeline network model construction module, a data parameter setting module, a calculation module, a first comparison and judgment module, a valve opening calculation module, an error calculation module, and a second comparison and judgment module. The pipeline network model construction module is used to construct a pipeline network model based on the actual ship's pipeline system. The data parameter setting module is used to set the data parameters of various components in the pipeline network model and the fluid parameters within the pipeline network, and sets the valve resistance coefficient to the minimum; at this point, the corresponding resistance coefficient of the valve is the first valve resistance coefficient. The calculation module is used to calculate the first flow rate value and turbulence intensity value in each pipeline segment based on the data parameters, fluid parameters, and the first valve resistance coefficient. The first comparison and judgment module is used to compare the turbulence intensity value with a preset turbulence intensity range to determine whether the turbulence intensity value is within the preset turbulence intensity range; and to compare the first flow rate value corresponding to the turbulence intensity value within the preset turbulence intensity range with the first preset flow rate range to determine whether the first flow rate value is within the first preset flow rate range, and obtain the second valve resistance coefficient for each valve based on the first flow rate value within the first preset flow rate range. The valve opening calculation module is used to obtain the first valve opening based on the resistance coefficient-valve opening curve and the second valve resistance coefficient. The error calculation module is used to obtain the error value between the third flow rate value and the model flow rate value corresponding to the first valve opening. The second comparison and judgment module is used to determine whether the error value is within a preset error range. When the third flow rate value is within the preset error range, it determines whether the third flow rate value is within a second preset flow rate range. The valve opening corresponding to the third flow rate value that is within the second preset flow rate range is used as the final valve opening.

[0149] Optionally, the first comparison and judgment module further includes a turbulence intensity comparison and judgment module, a flow rate comparison and judgment module, and a trial calculation module. The turbulence intensity comparison and judgment module compares the turbulence intensity value with a preset turbulence intensity range to determine whether the turbulence intensity value falls within the preset turbulence intensity range. The flow rate comparison and judgment module compares the first flow rate value corresponding to the turbulence intensity value within the preset turbulence intensity range with a first preset flow rate range to determine whether the first flow rate value falls within the first preset flow rate range, and obtains the second valve resistance coefficient for each valve based on the first flow rate value within the first preset flow rate range. When the flow rate comparison and judgment module determines that the first flow rate value is not within the first preset flow rate range, the trial calculation module sets the flow rate value of each pipeline within the first preset flow rate range, defines the flow rate value within the first preset flow rate range as the second flow rate value, and calculates the second valve resistance coefficient for each valve based on the second flow rate value.

[0150] Optionally, the flow rate adjustment system also includes a resistance coefficient-valve opening-Reynolds number curve correction module and an orifice plate diameter parameter calculation module. The resistance coefficient-valve opening-Reynolds number curve correction module corrects the resistance coefficient-valve opening-Reynolds number curve based on the third valve resistance coefficient obtained when the final valve opening is executed in the actual ship piping system. The orifice plate diameter parameter calculation module calculates the fourth valve resistance coefficient based on the corrected resistance coefficient-valve opening curve correction module, calculates the orifice plate resistance coefficient based on the fourth valve resistance coefficient and the first valve resistance coefficient, and then calculates the orifice plate diameter parameter based on the orifice plate resistance coefficient.

[0151] In summary, this embodiment exhibits strong self-learning characteristics. As the "on-site flow error determination" in step S8 progresses, the deviation between the actual engineering value and the simulation calculation value gradually decreases, thereby improving the accuracy of the simulation solution. Furthermore, the accuracy of the flow resistance coefficient / valve opening curve also continuously improves. After multiple solutions and corrections, a high-precision model after training and optimization can be formed. The optimized implementation scheme is as follows: Figure 5 As shown, the valve resistance coefficient obtained through simulation calculation can be used to calculate and determine the geometric dimensions of the throttling orifice plate.

[0152] This embodiment verifies the calculation results through simulation debugging and subsequent actual ship debugging and operation data, continuously correcting and optimizing the calculation results to improve the accuracy and reliability of the debugging method. Furthermore, this invention comprehensively collects relevant data in the calculation and debugging process and establishes a database to provide a basis for system reliability assessment and subsequent general optimization design, and to provide data support and design guidance for ship production and operation.

[0153] The above embodiments are merely illustrative of the principles and effects of the present invention and are not intended to limit the invention. Any person skilled in the art can modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by those skilled in the art without departing from the spirit and technical concept disclosed in the present invention should still be covered by the claims of the present invention.

Claims

1. A method for adjusting the flow rate of a ship's cooling water system, characterized in that, include: S1: Construct a pipe network model of the ship's cooling water system. The pipe network model includes various components, including pipes and valves. S2: Set the data parameters of each component in the pipeline network model and the fluid parameters in the pipeline network, and set the resistance coefficient of the valve to the minimum. At this time, the resistance coefficient of the valve is the first valve resistance coefficient. S3: Based on the set values ​​of the data parameters, the set values ​​of the fluid parameters, the first valve resistance coefficient, and the relationship curve between the resistance coefficient and the Reynolds number when the valve is fully open, calculate the first flow rate and turbulence intensity value in each section of the pipeline. S4: Compare the turbulence intensity value with a preset turbulence intensity range to determine whether the turbulence intensity value is within the preset turbulence intensity range; S5: Compare the first flow rate value corresponding to the turbulence intensity value within the preset turbulence intensity range with the first preset flow rate range to determine whether the first flow rate value is within the first preset flow rate range, and obtain the second valve resistance coefficient of each valve based on the first flow rate value within the first preset flow rate range; S6: Obtain the first valve opening based on the resistance coefficient-valve opening curve and the second valve resistance coefficient; S7: Apply the first valve opening to the actual ship pipeline system to obtain the flow rate value in the actual ship pipeline system, and record it as the third flow rate value; S8: Calculate the error between the third flow rate value and the model flow rate value corresponding to the first valve opening, and determine whether the error value is within the preset error range; S9: Take the valve opening corresponding to the third flow value within the preset error range as the final valve opening, or continue to determine whether the third flow value is within the second preset flow range, and take the valve opening corresponding to the third flow value within the second preset flow range as the final valve opening.

2. The flow rate debugging method according to claim 1, characterized in that, The step of determining whether the turbulence intensity value is within the preset turbulence intensity range includes: When the turbulence intensity value is within the preset turbulence intensity range, proceed to step S5; When the turbulence intensity value is not within the preset turbulence intensity range, the pipe segment in the pipeline network model is adjusted, and the process returns to step S1.

3. The flow rate debugging method according to claim 1, characterized in that, The step of determining whether the first flow rate value is within the first preset flow rate range includes: When the first flow rate value is within the first preset flow rate range, the first valve resistance coefficient is the second valve resistance coefficient; When the first flow rate value is not within the first preset flow rate range, the flow rate value of each pipeline is set within the first preset flow rate range, and the flow rate value set within the first preset flow rate range is defined as the second flow rate value. The second valve resistance coefficient of each valve is calculated based on the second flow rate value.

4. The flow rate debugging method according to claim 3, characterized in that, The step of calculating the second valve resistance coefficient for each valve based on the second flow rate value includes: If the trial calculation is successful, the resistance coefficient of each valve that is successfully solved is the second valve resistance coefficient obtained for each valve. If the trial calculation fails, the pipeline system of the pipeline network model needs to be adjusted, and steps S1 to S5 are repeated until the second valve resistance coefficient of each valve is obtained.

5. The flow rate debugging method according to claim 1, characterized in that, The step of determining whether the error value is within the preset error range also includes: When the error value is within the preset error range, proceed to step S9; When the error value is not within the error range, the data parameters of the pipelines, valves and other components in the pipeline network model are corrected, and steps S1 to S8 are repeated until the error value is within the preset error range.

6. The flow rate debugging method according to claim 1, characterized in that, The step of determining whether the third flow value is within the second preset flow range includes: If the third flow rate value is within the second preset flow rate range, then the valve opening corresponding to the third flow rate value at this time is the final valve opening. If the third flow rate value is not within the second preset flow rate range, the pipe segment in the pipeline network model is adjusted, and the process returns to step S1 until the third flow rate value is within the second preset flow rate range. The valve opening at this time is recorded as the second valve opening, and the second valve opening is used as the final valve opening.

7. The flow rate debugging method according to claim 1, characterized in that, After determining the final valve opening, the following steps are also included: The final valve opening is executed in the actual ship piping system, and the actual resistance coefficient is obtained and recorded as the third valve resistance coefficient. At the same time, the Reynolds value is obtained. The resistance coefficient-valve opening-Reynolds number curve is corrected based on the final valve opening, the third valve resistance coefficient, and the Reynolds number.

8. The flow rate debugging method according to claim 7, characterized in that, The steps of executing the final valve opening in an actual ship piping system and obtaining the third valve resistance coefficient include: The resistance coefficient of the throttling orifice plate is calculated based on the resistance coefficient of the third valve and the resistance coefficient of the first valve. Calculate the orifice diameter parameters of the orifice plate based on its resistance coefficient; The final valve opening is determined by adjusting the orifice diameter parameters of the throttling orifice plate in the actual ship's piping system.

9. The flow rate debugging method according to claim 7, characterized in that, The steps for obtaining the resistance coefficient of the third valve include: The resistance coefficient of the third valve is calculated by using the differential pressure readings of pressure sensors installed in the actual ship's piping system.

10. The flow rate debugging method according to claim 7, characterized in that, After correcting the resistance coefficient-valve opening-Reynolds number curve, the following is also included: The fourth valve resistance coefficient for each valve at the corresponding valve opening is calculated using the modified resistance coefficient-valve opening-Reynolds numerical curve. The resistance coefficient of the throttling orifice plate is calculated based on the resistance coefficient of the fourth valve and the resistance coefficient of the first valve. Calculate the orifice diameter parameters of the orifice plate based on its resistance coefficient; The orifice diameter of the orifice plate in the actual ship piping system is inspected and corrected based on the orifice diameter parameters of the orifice plate.

11. A flow rate debugging system, characterized in that, include: The pipeline model building module is used to build a pipeline model based on the actual ship pipeline system. The data parameter setting module is used to set the data parameters of various components in the pipeline network model and the fluid parameters in the pipeline network, and to set the resistance coefficient of the valve to the minimum. At this time, the resistance coefficient of the valve is the first valve resistance coefficient. The calculation module is used to calculate the first flow rate value and turbulence intensity value in each section of the pipeline based on the data parameters, the fluid parameters and the first valve resistance coefficient; The first comparison and judgment module is used to compare the turbulence intensity value with a preset turbulence intensity range to determine whether the turbulence intensity value is within the preset turbulence intensity range; and to compare the first flow rate value corresponding to the turbulence intensity value being within the preset turbulence intensity range with the first preset flow rate range to determine whether the first flow rate value is within the first preset flow rate range, and to obtain the second valve resistance coefficient of each valve based on the first flow rate value being within the first preset flow rate range; The valve opening calculation module is used to obtain the first valve opening based on the resistance coefficient-valve opening curve and the second valve resistance coefficient. The error calculation module obtains a third flow value when the first valve opening is applied to the actual ship pipeline. The error calculation module is used to calculate the error value between the third flow value and the model flow value corresponding to the first valve opening. The second comparison and judgment module is used to determine whether the error value is within a preset error range. When the third flow value is within the preset error range, it determines whether the third flow value is within a second preset flow range, and uses the valve opening corresponding to the third flow value within the second preset flow range as the final valve opening.

12. The flow rate debugging system according to claim 11, characterized in that, The first comparison and judgment module also includes: The turbulence intensity comparison and judgment module is used to compare the turbulence intensity value with a preset turbulence intensity range to determine whether the turbulence intensity value is within the preset turbulence intensity range. The flow comparison and judgment module compares the first flow value corresponding to the turbulence intensity value within the preset turbulence intensity range with the first preset flow range to determine whether the first flow value is within the first preset flow range, and obtains the second valve resistance coefficient of each valve based on the first flow value within the first preset flow range. In the trial calculation module, when the flow comparison and judgment module determines that the first flow value is not within the first preset flow range, the trial calculation module sets the flow value of each pipeline within the first preset flow range, defines the flow value set within the first preset flow range as the second flow value, and calculates the second valve resistance coefficient of each valve based on the second flow value.

13. The flow rate debugging system according to claim 11, characterized in that, The flow debugging system also includes: The drag coefficient-valve opening-Reynolds number curve correction module is used to correct the drag coefficient-valve opening-Reynolds number curve based on the third valve drag coefficient, the final valve opening and Reynolds number obtained when the final valve opening is executed in the actual ship piping system. The orifice plate diameter parameter calculation module is used to calculate the resistance coefficient of the fourth valve based on the corrected resistance coefficient-valve opening-Reynolds number curve correction module, calculate the resistance coefficient of the orifice plate based on the resistance coefficient of the fourth valve and the resistance coefficient of the first valve, and then calculate the orifice plate diameter parameter based on the resistance coefficient of the orifice plate.

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