A ship regional seawater cooling system flow balance control method

Abstract

The present application belongs to the field of ship and ocean engineering manufacturing technology, and particularly relates to a ship regional seawater cooling system flow balance control method, comprising: full opening of each branch remote control valve; adjusting the bypass pipeline flow to reach a set value; adjusting according to the branch flow from large to small; if the flow of other branches or the total pipe exceeds the tolerance range during the adjustment of the branch, repeating step S3 until the flow adjustment of the branch with the smallest flow is completed; when the flow of each branch is within the tolerance range, the flow reaches balance, and the adjustment is completed. The present application can automatically control the opening degree of the remote control valve of each branch, automatically adjust the cooling water flow of each branch, establish new flow balance, and make the whole regional seawater cooling system run smoothly when the water volume of each branch of the regional seawater cooling system changes, greatly reducing the difficulty of personnel operation.

Description

Technical Field

[0001] This invention relates to the field of shipbuilding and marine engineering manufacturing technology, and in particular to a method for flow balance control of a ship's regional seawater cooling system. Background Technology

[0002] Large marine transport platforms such as engineering vessels, offshore engineering projects, and luxury cruise ships are equipped with numerous and diverse mechanical devices, many of which require large amounts of cooling seawater to maintain normal operation. Small vessels typically use dedicated seawater cooling pumps for each piece of equipment; however, for large vessels and offshore engineering projects, due to the large number of devices, the trend is towards a unified cooling seawater supply to all equipment in designated areas, along with centralized monitoring of each area. Regional seawater cooling systems use fewer cooling pumps, which is beneficial for ship management and reduces ship weight. However, the large number of cooling devices served by a regional seawater cooling system inevitably leads to system complexity.

[0003] Currently, most common regional seawater cooling water systems employ manual control measures, leading to the following technical problems:

[0004] 1) During the commissioning of the regional seawater cooling system, it is difficult to adjust the flow balance of each branch and the commissioning cycle is long.

[0005] 2) Dynamic hydraulic imbalance is prone to occur in cooling water pipe networks. In regional seawater cooling systems, when a cooling water user stops operating and the cooling water supply to its branch is cut off, the flow change in that branch will affect the original system flow balance, resulting in uneven flow distribution throughout the cooling system and failure to meet usage requirements.

[0006] It should be noted that the information disclosed in the background section above is only used to enhance the understanding of the background of the present invention, and therefore may include information that does not constitute prior art known to those skilled in the art. Summary of the Invention

[0007] The purpose of this invention is to solve the technical problems existing in the background art. To this end, a flow balance control method for a ship's regional seawater cooling system is provided. Through reasonable remote control valve adjustment logic, the regional seawater cooling system can quickly and efficiently establish a new system flow balance under changing operating conditions, reducing the difficulty of operation for crew members.

[0008] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0009] A method for flow balance control of a ship's regional seawater cooling system includes the following steps:

[0010] Step S1: Open all remote control valves on each branch;

[0011] Step S2: Adjust the flow rate of the bypass pipeline to reach the set value;

[0012] Step S3: Adjust the branch flow rates in descending order;

[0013] Step S4: If the flow rate of other branches or the main pipe exceeds the tolerance range when adjusting the branch, repeat step S3 until the branch with the minimum flow rate completes the flow rate adjustment.

[0014] Step S5: When the flow rate of each branch is within the tolerance range, the flow rate reaches balance, and the adjustment ends.

[0015] The following is a further defined technical solution of the present invention: the bypass pipeline and each branch are monitored for flow in real time by a flow meter, and the flow meter is electrically connected to the controller.

[0016] The following is a further defined technical solution of the present invention: the remote control valve is configured as a remote control flow regulating valve, and the remote control valve is electrically connected to the controller.

[0017] The following is a further defined technical solution of the present invention, wherein the tolerance range of branch flow or main pipe flow is 0 to 10%.

[0018] The following is a further defined technical solution of the present invention: when adjusting the flow rate of the bypass pipeline, the remote control valve adjusts the opening degree in an adjustment step of 1% and an adjustment cycle of 1 second.

[0019] The following is a further defined technical solution of the present invention: when the actual flow rate of the branch deviates from the set value by 0 to 10%, the remote control valve does not make any adjustment.

[0020] The following is a further defined technical solution of the present invention: when adjusting the branch flow, the deviation between the actual flow of the branch and the set value is 10-20% or -10-0%, and the remote control valve adjusts the opening by adjusting the step size of 0.5% and the adjustment cycle of 0.3s.

[0021] The following is a further defined technical solution of the present invention: when adjusting the branch flow, the deviation between the actual flow of the branch and the set value is 20-40% or -30--10%, and the remote control valve adjusts the opening by adjusting the step size of 1% and the adjustment cycle of 0.3s.

[0022] The following is a further defined technical solution of the present invention: when adjusting the branch flow, if the actual flow of the branch deviates from the set value by more than 40% or less than -30%, the remote control valve adjusts the opening by an adjustment step of 3% and an adjustment cycle of 0.3s.

[0023] The following is a further defined technical solution of the present invention. The method is used to achieve flow balance in a ship area seawater cooling system, wherein the ship area seawater cooling system includes: a main pipeline, a bypass pipeline, and multiple cooling branches;

[0024] A seawater tank, a shut-off valve, a centrifugal water pump, and a shut-off check valve are installed sequentially on the main pipeline.

[0025] A flow meter, a shut-off valve, a flow regulating valve, a pressure sensor, and two shut-off check valves are installed sequentially on the bypass pipeline.

[0026] A static balancing valve, a flow meter, a flow regulating valve, two parallel user branches, and a shut-off check valve are sequentially installed on the cooling branch.

[0027] The user branch line is equipped with a static balancing valve, a cooling device, a flow meter, a pressure sensor, and a shut-off check valve in sequence.

[0028] Compared with the prior art, the present invention has the following technical effects:

[0029] This invention designs a flow balance control method for a ship's regional seawater cooling system. When the water volume in each branch of the regional seawater cooling system changes, the method can automatically adjust the cooling water flow in each branch by controlling the opening of the remote-controlled valves, establish a new flow balance, and ensure the stable operation of the entire regional seawater cooling system, greatly reducing the difficulty of operation for personnel.

[0030] The present invention will be further described below with reference to the accompanying drawings and embodiments. Attached Figure Description

[0031] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0032] Figure 1 This is a schematic diagram of the connection relationship of the ship area seawater cooling system in this invention;

[0033] Figure 2 This is a schematic diagram of the branch variable step size adjustment strategy in this invention;

[0034] Figure 3 This is a flowchart of the method of the present invention. Detailed Implementation

[0035] To make the above-mentioned objects, features, and advantages of the present invention more apparent and understandable, specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings. Many specific details are set forth in the following description to provide a thorough understanding of the present invention. However, the present invention can be practiced in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0036] This embodiment uses Figure 1 Taking the ship's regional seawater cooling system shown as an example, the control method of this embodiment will be explained.

[0037] The ship's regional seawater cooling system includes: a main pipeline, a bypass pipeline, and three cooling branch lines. The main pipeline is equipped with, in sequence, a seawater tank, a shut-off valve, a centrifugal water pump, and a shut-off check valve. The bypass pipeline is equipped with, in sequence, a flow meter, a shut-off valve, a flow regulating valve, a pressure sensor, and two shut-off check valves. The cooling branch lines are equipped with, in sequence, a static balancing valve, a flow meter, a flow regulating valve, two parallel user branches, and shut-off check valves; specifically, the user branches are equipped with, in sequence, a static balancing valve, cooling equipment, a flow meter, a pressure sensor, and a shut-off check valve.

[0038] The ship's regional seawater cooling system draws water from the seawater tank using centrifugal pumps and employs a two-stage flow control system consisting of a main pipeline (i.e., the main pipe) and branch pipelines (i.e., bypass pipelines and three cooling branch lines). Each user branch line is equipped with a static balancing valve (or other manually controlled valve) to ensure that the flow distribution in each branch line meets the usage requirements under rated operating conditions. Simultaneously, each cooling branch line is equipped with a remote-controlled flow regulating valve and a flow meter. When the flow rate of the regional seawater cooling system fluctuates or when the flow rate is redistributed due to the start-up and shutdown of the cooled equipment, the flow meter feedback closed-loop control adjusts the opening of the remote-controlled valve to establish a new balance in the system's cooling water flow.

[0039] This embodiment provides a flow balance control method for a ship's regional seawater cooling system, which includes key strategy points such as flow control points, control strategy parameters, variable step size adjustment, branch adjustment sequence, and system flow balance control process. For example, if the flow rate is too high and exceeds the tolerance, the opening degree is calculated based on the flow deviation and the characteristics of the regulating valve and pipeline. If the flow rate is adjusted to within the tolerance range, the adjustment is complete.

[0040] Flow control point: The tolerance range for branch flow or main pipe flow is 0-10%, that is: control is carried out according to the total deviation of the cooling water demand flow of each cooling water user in the main pipe or branch pipe from 0-10%.

[0041] For bypass pipelines, the flow rate of the pump outlet flow meter is used as the input. The sum of the required flow rates of each branch is subtracted to obtain the required flow rate for bypass. The opening of the bypass valve is adjusted, and the adjustment is stopped when the bypass flow meter reaches this value.

[0042] Control strategy parameters: The parameters that affect the system settling time mainly include the adjustment period T and the adjustment step size of the remote flow control valve opening.

[0043] Variable step size adjustment: segmented processing based on flow deviation; such as Figure 2 As shown, specifically:

[0044] (1) Branch road:

[0045] When the current flow rate deviates from the design flow rate by 0-10%, the remote-controlled flow regulating valve should not be adjusted.

[0046] When the current flow rate deviates from the design flow rate by 10-20% or -10-0%, the remote-controlled flow regulating valve adjusts its opening by an adjustment step of 0.5% and an adjustment cycle of 0.3s.

[0047] When the current flow rate deviates from the design flow rate by 20-40% or -30--10%, the remote-controlled flow regulating valve adjusts its opening by an adjustment step of 1% and an adjustment cycle of 0.3s.

[0048] When the current flow rate deviates from the design flow rate by more than 40% or less than -30%, the remote-controlled flow regulating valve adjusts its opening by an adjustment step of 3% and an adjustment cycle of 0.3s.

[0049] (2) Bypass pipe:

[0050] The bypass pipeline is always adjusted in 1% increments with a 1-second adjustment cycle.

[0051] Branch adjustment sequence: Set two adjustment strategies: coarse adjustment (3%, 1%) and fine adjustment (0.5%).

[0052] When the operating conditions begin to switch, each branch and bypass branch simultaneously begin to adjust according to the coarse adjustment strategy. When a branch reaches the flow control range, the remote control flow regulating valve of the branch switches to fine adjustment mode until each branch reaches the set flow control range.

[0053] System flow balancing control process: mainly includes:

[0054] The flow rate of the bypass pipeline and each branch is monitored in real time by a flow meter, which is electrically connected to the controller.

[0055] All branch remote control valves are fully open. The remote control valves are configured as remote-controlled flow regulating valves and are electrically connected to the controller.

[0056] Adjust the flow rate of the bypass pipeline to reach the set value.

[0057] Adjustments are made according to the branch flow rate from highest to lowest.

[0058] If adjusting a branch causes the flow rate of other branches or the main pipe to exceed the tolerance range, repeat step S3 until the branch with the minimum flow rate completes the flow rate adjustment.

[0059] When the flow rate of each branch is within the tolerance range, the flow rate reaches equilibrium, and the adjustment ends.

[0060] like Figure 3 The above process will be further described as follows:

[0061] 1. All remote control regulating valves on each branch are fully open.

[0062] 2. Adjust the flow rate of the bypass pipeline to reach the set value.

[0063] 3. Adjust the branch with the maximum design flow to the set value; adjusting the branch flow will affect the flow of other branches or the main pipe flow.

[0064] 4. Determine if the bypass flow rate exceeds the tolerance;

[0065] 5. If the result exceeds the limit, repeat steps 2-4.

[0066] 6. If the limit is not exceeded, proceed to the next step.

[0067] 7. Adjust the secondary flow branch to reach the set value.

[0068] 8. Determine whether the flow rate of the branch that has been adjusted exceeds the tolerance.

[0069] 9. If the result exceeds the limit, repeat steps 3-8.

[0070] 10. If not exceeded, proceed to the next step.

[0071] 11. Adjust the smaller flow branch to reach the set value.

[0072] 12. Determine whether the flow rate of the branch that has been adjusted exceeds the tolerance.

[0073] 13. If the result exceeds the limit, repeat step 3-12.

[0074] 14. If not exceeded, proceed to the next step.

[0075] 15. Continue in this manner, adjusting the branch flow rate in sequence until the branch with the minimum flow rate reaches the set value;

[0076] 16. Determine whether the flow rate of the branch that has been adjusted exceeds the tolerance.

[0077] 17. If the result exceeds the limit, repeat step 3-16.

[0078] 18. If the flow rate is not exceeded, it means that the system has reached flow balance and the adjustment is over.

[0079] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. Any person skilled in the art can make many possible variations and modifications to the technical solution of the present invention, or modify it into equivalent embodiments, without departing from the scope of the present invention's technical solution. Therefore, all equivalent changes made based on the shape, structure, and principle of the present invention without departing from the scope of the present invention's technical solution should be covered within the protection scope of the present invention.

Claims

1. A flow balance control method for a ship's regional seawater cooling system, the method being used to achieve flow balance in the ship's regional seawater cooling system, characterized in that, The ship's regional seawater cooling system includes: main piping, bypass piping, and multiple cooling branch lines; A seawater tank, a shut-off valve, a centrifugal water pump, and a shut-off check valve are installed sequentially on the main pipeline. A flow meter, a shut-off valve, a flow regulating valve, a pressure sensor, and two shut-off check valves are installed sequentially on the bypass pipeline. A static balancing valve, a flow meter, a flow regulating valve, two parallel user branches, and a shut-off check valve are sequentially installed on the cooling branch. Among them, a static balancing valve, a cooling device, a flow meter, a pressure sensor, and a shut-off check valve are installed sequentially on the user branch line; The method includes the following steps: Step S1: Open all remote control valves on each branch; Step S2: Adjust the flow rate of the bypass pipeline to reach the set value; Step S3: Adjust the branch flow rates in descending order; Step S4: If the flow rate of other branches or the main pipe exceeds the tolerance range when adjusting the branch, repeat step S3 until the branch with the minimum flow rate completes the flow rate adjustment. Step S5: When the flow rate of each branch is within the tolerance range, the flow rate reaches equilibrium, and the adjustment ends; When the actual flow rate of the branch deviates from the set value by 0-10%, the remote control valve will not make any adjustment. When adjusting the branch flow, if the actual flow of the branch deviates from the set value by 10~20% or -10~0%, the remote control valve adjusts the opening by adjusting the step size of 0.5% and the adjustment cycle of 0.3s. When adjusting the branch flow, if the actual flow of the branch deviates from the set value by 20~40% or -30~-10%, the remote control valve adjusts the opening by adjusting the step size of 1% and the adjustment cycle of 0.3s. When adjusting the branch flow, if the actual flow of the branch deviates from the set value by more than 40% or less than -30%, the remote control valve adjusts the opening by an adjustment step of 3% and an adjustment cycle of 0.3s.

2. The flow balance control method for a ship's regional seawater cooling system as described in claim 1, characterized in that, The flow rate of the bypass pipeline and each branch is monitored in real time by a flow meter, which is electrically connected to the controller.

3. The flow balance control method for a ship's regional seawater cooling system as described in claim 1, characterized in that, The remote control valve is configured as a remote-controlled flow regulating valve, and is electrically connected to the controller.

4. The flow balance control method for a ship's regional seawater cooling system as described in claim 1, characterized in that, The tolerance range for branch flow or main flow is 0-10%.

5. The flow balance control method for a ship's regional seawater cooling system as described in claim 1, characterized in that, When adjusting the flow rate of the bypass pipeline, the remote control valve adjusts the opening by adjusting the step size in 1% and the adjustment cycle in 1 second.

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