Shield wharf wave numerical value processing method

Abstract

The invention discloses a wave numerical value processing method for a shielded wharf, which relates to the technical field of wave forecasting and comprises the following steps of: obtaining a specific relational expression between forecast values and measured values of model boundary wave conditions and wind condition parameters; setting a wave mathematical model by adopting swan wave numerical simulation software, and simulating to obtain predicted values of historical in-port wave conditions and wind condition parameters by combining the predicted values of the historical model boundary wave conditions and wind condition parameters; deducing to obtain a specific relational expression between the forecast value and the measured value of the wave condition and wind condition parameters in the harbor; obtaining forecast values of the latest wave condition and wind condition parameters of the model boundary, and correcting the forecast values; and performing simulation to obtain initial forecast values of the wave conditions and the wind condition parameters in the harbor, and performing correction to obtain final forecast values of the wave conditions and the wind condition parameters in the harbor. According to the method, the forecast value of the in-port wave of the shielded wharf can be obtained according to the forecast value of the out-port wave, so that the operation arrangement of ships in the port is guided, and basic data support is provided for the operation management of the port.

Description

Technical Field

[0001] The present invention relates to the technical field of wave forecasting, and more particularly to a wave numerical processing method for a sheltered pier. Background Art

[0002] Wave data, as an important basic input condition, affects the safety of port operations. At present, there are generally two methods for obtaining waves in the port: 1) real-time monitoring through buoys, but this monitoring has the characteristics of delay and cannot carry out refined management of the operation of port ships; 2) purchasing data from existing forecast models, such as Windy forecast data, but these data only have forecast values ​​for waves outside the port, and no forecast values ​​for waves in the protected dock port, so they cannot directly guide the operation arrangements of ships in the port. The prior art, such as the invention patent application with application publication number CN110728042A, discloses a method for quickly forecasting long-term scale coastal wave elements, which can realize the prediction of nearshore wave elements based on long-term scale wind conditions, wave conditions and tide level data in the open sea. However, in actual applications, the marine environment changes rapidly, resulting in poor real-time performance of the predicted nearshore wave elements. If the data is not updated in time, the forecast results may be out of touch with the actual situation, and there is room for improvement. Summary of the invention

[0003] An object of the present invention is to provide a numerical processing method for waves at a sheltered wharf, which realizes wave forecasting in the port, adapts to changes in the marine environment, and effectively improves the accuracy of the forecast.

[0004] In order to achieve these objectives and other advantages of the present invention, according to one aspect of the present invention, the present invention provides a wave numerical processing method for a sheltered pier, comprising the following steps: Step 1: obtaining the predicted values ​​and measured values ​​of the boundary wave and wind condition parameters of the historical model outside the port, and deriving a specific relationship formula 1 between the predicted values ​​and measured values ​​of the boundary wave and wind condition parameters of the model outside the port; Step 2: using SWAN wave numerical simulation software to set up a mathematical model of waves in the port, combining the predicted values ​​of the boundary wave conditions and wind condition parameters of the historical model outside the port, and simulating the predicted values ​​of the historical wave conditions and wind condition parameters in the port; Step 3: obtaining the measured values ​​of the historical wave and wind parameters in the port, combining the predicted values ​​of the historical wave and wind parameters in the port, and deriving a second specific relationship between the predicted values ​​and the measured values ​​of the wave and wind parameters in the port; Step 4: obtaining the forecast value and measured value of the latest wave condition and wind condition parameters of the model boundary outside the port, and correcting the forecast value of the latest wave condition and wind condition parameters of the model boundary outside the port according to the specific relationship formula 1 between the forecast value and the measured value of the wave condition and wind condition parameters of the model boundary outside the port, so as to obtain the forecast value of the latest wave condition and wind condition parameters of the model boundary after correction; Step 5: According to the mathematical model of the wave in the harbor, combined with the forecast values ​​of the latest wave and wind parameters at the modified model boundary, simulate and obtain the initial forecast values ​​of the wave and wind parameters in the harbor; Step six, obtaining the measured values ​​of the latest wave and wind parameters in the port, and correcting the initial forecast values ​​of the wave and wind parameters in the port according to the specific relationship between the forecast values ​​and the measured values ​​of the wave and wind parameters in the port to obtain the final forecast values ​​of the wave and wind parameters in the port.

[0005] Preferably, the wave and wind condition parameters include wave height, wave period, wave direction, wind speed and wind direction.

[0006] Preferably, the forecast values ​​of the wave and wind condition parameters at the historical model boundary outside the port and the forecast values ​​of the latest wave and wind condition parameters at the model boundary outside the port both use Windy forecast data, and the measured values ​​of the wave and wind condition parameters at the historical model boundary outside the port and the measured values ​​of the wave and wind condition parameters in the historical port are both obtained by measuring by arranging buoy measuring stations.

[0007] Preferably, the first specific relationship between the predicted values ​​and the measured values ​​of the wave and wind condition parameters of the outer port model boundary and the second specific relationship between the predicted values ​​and the measured values ​​of the wave and wind condition parameters inside the port are obtained by drawing scatter plots and deriving using polynomial fitting.

[0008] Preferably, in step 2, the swan wave numerical simulation software is used to set the mathematical model of the waves in the harbor, including the setting of model parameters and the setting of the model terrain file, wherein the model parameter setting includes the bottom friction parameter and the breaking parameter, both of which adopt the model recommended values; and the model terrain file is generated by SMS terrain making software.

[0009] Preferably, an updating mechanism is further included, i.e., the process of step 1 and step 3 is repeated irregularly to update the specific relationship between the predicted value and the measured value of the wave condition and wind condition parameters at the boundary of the port model and the specific relationship between the predicted value and the measured value of the wave condition and wind condition parameters in the port, specifically: Cluster analysis of marine environmental changes was performed, and marine environmental changes were divided into calm periods, general change periods, and drastic change periods: During the calm period, continuously accumulating the predicted values ​​and measured values ​​of the wave and wind condition parameters of the historical model boundary outside the port, as well as the predicted values ​​and measured values ​​of the wave and wind condition parameters in the historical port, and repeating the process of step 1 and step 3 every 1 to 3 months; During the general change period, the change range of each parameter is monitored in real time. If the cumulative change range of each parameter exceeds a certain threshold, the process of step 1 and step 3 is immediately repeated; During the period of drastic changes, the process of steps 1 and 3 was repeated every 15 to 30 minutes.

[0010] Preferably, during the general change period, the threshold values ​​of the change amplitudes of various parameters are: wave height change 0.5~1.2m, wind speed change 3~6m / s.

[0011] Preferably, the determination method of the quiet period, the normal change period and the drastic change period is: When the wave height is less than 0.3m, the wind speed is less than 3m / s, the current speed is weak, and the water temperature and salinity remain relatively constant, the sea area is judged to be in a calm period; When the wave height is between 0.3 and 0.6 m, the wind speed is between 3 and 6 m / s, the current speed is less than 0.5 knots, the water temperature is between 15 and 18 °C, and the salinity is between 34‰ and 35‰, the sea area is judged to have entered a general change period; When the wave height is greater than 1.5m, the wind speed is greater than 10m / s, the current speed is greater than 1 knot, the water temperature changes suddenly by more than 2°C, and the salinity fluctuates by more than 1‰, the sea area is judged to have entered a period of drastic changes.

[0012] The present invention includes at least the following beneficial effects: the present invention obtains the forecasted values ​​and measured values ​​of the boundary wave and wind parameters of the historical model outside the port, as well as the forecasted values ​​and measured values ​​of the wave and wind parameters in the historical port, respectively derives specific relationship expressions therebetween, and uses these relationship expressions to correct the forecasted values. This method of establishing and correcting relationships based on actual data effectively improves the accuracy of wave forecasts in the port; by performing cluster analysis on changes in the ocean environment, dividing the period into calm periods, general change periods and drastic change periods, and updating specific relationship expressions at different frequencies in different periods, the forecasting method can better adapt to the complex and changeable ocean environment, thereby ensuring the timeliness and accuracy of the forecast results.

[0013] Other advantages, objectives and features of the present invention will be embodied in part through the following description, and in part will be understood by those skilled in the art through study and practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 The present invention is a flowchart of a method for numerically processing waves of a sheltered wharf in a technical solution of the present invention.

[0015] Figure 2 It is a scatter plot of the measured values ​​and predicted values ​​of the wave height at the southern boundary of the historical model outside the port in Example 1 of the present invention.

[0016] Figure 3 This is a schematic diagram of the terrain file of the mathematical model of harbor waves in Example 1 of the present invention.

[0017] Figure 4 This is the wave forecast result at a certain moment in Example 1 of the present invention. DETAILED DESCRIPTION

[0018] The present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments so that those skilled in the art can implement the invention with reference to the description.

[0019] It should be understood that the terms such as “having”, “including” and “comprising” used herein do not exclude the existence or addition of one or more other elements or combinations thereof.

[0020] Example 1 Wave forecast for a certain fishing port Step 1: Derive the relationship at the southern boundary of the model Obtain the predicted values ​​(Windy forecast data) and measured values ​​(obtained through measurements at buoy stations) of wave conditions (wave height, wave period, wave direction) and wind conditions (wind speed, wind direction) parameters at the southern boundary of the historical model outside the port.

[0021] Taking wave height as an example, a scatter plot of measured values ​​and predicted values ​​is drawn (see Figure 2), and a polynomial fitting is used to obtain the relationship, such as , correlation coefficient R=0.92, and other parameters were calculated using similar methods.

[0022] Step 2: Set up the mathematical model of the harbor wave and simulate the historical parameters of the harbor The model terrain file was generated using SMS terrain making software (see Figure 3), and the mathematical model parameters of the harbor wave were set based on the dynamic spectrum balance equation formula (the recommended values ​​were used for bottom friction parameters and breaking parameters).

[0023] Obtain the forecast values ​​of wave and wind condition parameters at the boundary of the historical model outside the port, and use the SWAN wave numerical simulation software, combined with the model settings, to simulate and obtain the forecast values ​​of wave and wind condition parameters inside the historical port.

[0024] Step 3: Derive the relationship between the wave parameters in the port The actual measured values ​​of historical wave and wind conditions in the port are obtained through observation equipment such as buoys in the port.

[0025] Using a method similar to step 1, the relationship between the measured and predicted values ​​of the wave and wind conditions parameters in the port is obtained.

[0026] Step 4: Obtain and correct the latest forecast value of the southern boundary outside the port Use Windy to obtain the latest forecast values ​​of wave and wind parameters at the southern boundary of the model outside the port.

[0027] According to the relationship obtained in step 1, the latest forecast data is corrected to obtain the corrected latest wave and wind condition parameter forecast values.

[0028] The correction process is as follows: after obtaining the latest wave height forecast value at the southern boundary of the model outside the port, substitute it into the above relationship to calculate the corresponding theoretical measured value. Then, compare the theoretical measured value with the latest measured sample value actually obtained. If it is found that there is a deviation from the expectation, it can be adjusted according to the deviation. For example, if the theoretical measured value is significantly larger than the measured sample, the forecast value can be appropriately reduced; otherwise, it can be appropriately increased. The amplitude of the adjustment is determined according to the linear adjustment strategy.

[0029] For other wave parameters (wave period, wave direction) and wind parameters (wind speed, wind direction), the latest forecast values ​​are corrected according to the above steps to ensure the accuracy of boundary parameters, thus providing a more reliable basis for the subsequent simulation and correction of wave parameters in the port.

[0030] Step 5: Simulate the initial forecast value in the port Based on the mathematical model of harbor waves set in step 2, combined with the revised forecast values ​​of the latest wave and wind parameters at the southern boundary, the initial forecast values ​​of the harbor wave and wind parameters are obtained using the SWAN wave numerical simulation software.

[0031] Step 6: Calculate the final forecast value in the port Combined with the relationship between the measured and predicted values ​​of the wave and wind parameters in the port obtained in step 3, the initial predicted values ​​are corrected to obtain the final predicted values ​​of the wave and wind parameters in the port (see Figure 4). The correction process is the same as above.

[0032] Real-time monitoring and updated judgment During the quiet period, repeat steps 1 and 3 every 2 months to accumulate more data and update the relationship to ensure forecast accuracy.

[0033] During the general change period, a professional marine environment monitoring system is used to monitor key parameters such as wave height and wind speed in real time 24 hours a day. For example, the port is equipped with high-precision wave height meters and wind speed sensors, and data is automatically collected and transmitted to the monitoring center every 10 minutes.

[0034] Set the change amplitude threshold. When the cumulative change of wave height reaches 0.8m and the cumulative change of wind speed reaches 4m / s, the system automatically issues an alarm and triggers the update mechanism. Assume that in a certain day of monitoring, starting from 8 am, the wave height gradually increases from the initial 0.4m, and by 2 pm, it has accumulated a 0.8m increase. At the same time, the wind speed increases from 5m / s to 9m / s, and the cumulative change reaches 4m / s. The monitoring system immediately starts the subsequent update process.

[0035] During the period of drastic changes, steps 1 and 3 were automatically repeated every 20 minutes with the help of an automated data acquisition and processing system.

[0036] The specific updating process is as follows: re-collect the measured and predicted values ​​of the new wave and wind parameters at the southern boundary of the model outside the port, re-draw the scatter plot and perform polynomial fitting, and update the relationship between the measured and predicted values ​​of the wave and wind parameters at the southern boundary of the model outside the port. For the wave and wind parameters inside the port, the latest measured values ​​are also obtained, combined with the current forecast values, the scatter plot is drawn again and fitted, and the relationship between the measured and predicted values ​​of the wave and wind parameters inside the port is updated.

[0037] The latest forecast values ​​of wave and wind parameters at the southern boundary of the model outside the port are obtained from Windy again, and these latest forecast values ​​are corrected according to the updated relationship at the southern boundary of the model outside the port.

[0038] Based on the established mathematical model of in-harbor waves (the model parameters and terrain files remain unchanged and can be adjusted according to actual conditions if there are special circumstances), combined with the revised forecast values ​​of the latest wave and wind parameters at the southern boundary, the initial forecast values ​​of the in-harbor wave and wind parameters are calculated using the swan wave numerical simulation software.

[0039] Finally, the initial forecast values ​​are corrected based on the updated relationship between the measured values ​​and forecast values ​​of the wave and wind parameters in the port, thus obtaining the final forecast values ​​of the wave and wind parameters in the port. Based on these latest forecast data, the port operation management department can timely adjust the ship's loading and unloading plans, entry and exit arrangements, etc. to ensure the safety and efficiency of port operations.

[0040] Table 1 Comparison of measured and predicted values ​​of wave parameters in the harbor (taking wave height as an example) time Measured value of wave height in the harbor (m) Final forecast value of wave height in the harbor (m) Error value (m) 2024-10-10 08:00 0.65 0.64 0.01 2024-10-11 12:00 0.91 0.93 -0.02 2024-10-12 16:00 0.75 0.72 0.03 2024-10-13 20:00 1.02 1.03 -0.01 It can be seen from Table 1 that the error value between the predicted value of the wave height in the port measured by the method of the present invention and the actual value of the wave height in the port (the difference between the actual value of the wave height in the port and the final predicted value of the wave height in the port) is very small, which proves that the wave numerical processing method for the protected wharf of the present invention can effectively improve the accuracy of the prediction of the wave condition parameters in the port.

[0041] Table 2 Comparison of forecast accuracy improvement after model update in different periods Average error of wave height forecast before update (m) Average error of updated wave height forecast (m) Calm period 0.25 0.15 General change period 0.20 0.12 Period of drastic changes 0.30 0.18 It can be seen from Table 2 that in different periods of marine environmental change, according to the set update mechanism (update every 2 months in calm period, update when threshold is reached in general change period, update every 20 minutes in drastic change period), after re-collecting data and updating the relationship, the average error of wave height forecast is significantly reduced, which proves that the update mechanism of the present invention can effectively improve the accuracy of forecast and provide a more reliable basis for port operation management.

[0042] Although the embodiments of the present invention have been disclosed as above, they are not limited to the applications listed in the specification and the implementation modes, and they can be fully applied to various fields suitable for the present invention. For those familiar with the art, additional modifications can be easily implemented. Therefore, without departing from the general concept defined by the claims and the scope of equivalents, the present invention is not limited to the specific details and the illustrations shown and described herein.

Claims

1. A method for numerically processing waves at a sheltered pier, characterized in that: The following steps are involved: Step 1: obtaining the predicted values ​​and measured values ​​of the boundary wave and wind condition parameters of the historical model outside the port, and deriving a specific relationship formula 1 between the predicted values ​​and measured values ​​of the boundary wave and wind condition parameters of the model outside the port; Step 2: using SWAN wave numerical simulation software to set up a mathematical model of waves in the port, combining the predicted values ​​of the boundary wave conditions and wind condition parameters of the historical model outside the port, and simulating the predicted values ​​of the historical wave conditions and wind condition parameters in the port; Step 3: obtaining the measured values ​​of the historical wave and wind parameters in the port, combining the predicted values ​​of the historical wave and wind parameters in the port, and deriving a second specific relationship between the predicted values ​​and the measured values ​​of the wave and wind parameters in the port; Step 4: obtaining the forecast value and measured value of the latest wave condition and wind condition parameters of the model boundary outside the port, and correcting the forecast value of the latest wave condition and wind condition parameters of the model boundary outside the port according to the specific relationship formula 1 between the forecast value and the measured value of the wave condition and wind condition parameters of the model boundary outside the port, so as to obtain the forecast value of the latest wave condition and wind condition parameters of the model boundary after correction; Step 5: According to the mathematical model of the wave in the harbor, combined with the forecast values ​​of the latest wave and wind condition parameters at the modified model boundary, simulate and obtain the initial forecast values ​​of the wave and wind condition parameters in the harbor; Step six, obtaining the measured values ​​of the latest wave and wind parameters in the port, and correcting the initial forecast values ​​of the wave and wind parameters in the port according to the specific relationship between the forecast values ​​and the measured values ​​of the wave and wind parameters in the port to obtain the final forecast values ​​of the wave and wind parameters in the port.

2. The method for numerically processing waves of a sheltered pier according to claim 1, characterized in that: The wave and wind condition parameters include wave height, wave period, wave direction, wind speed and wind direction.

3. The method for numerically processing waves of a sheltered pier according to claim 1, characterized in that: The forecast values ​​of the wave and wind condition parameters at the historical model boundary outside the port and the forecast values ​​of the latest wave and wind condition parameters at the model boundary outside the port all use Windy forecast data, and the measured values ​​of the wave and wind condition parameters at the historical model boundary outside the port and the measured values ​​of the wave and wind condition parameters in the historical port are all obtained by measuring and arranging buoy measuring stations.

4. The method for numerically processing waves of a sheltered pier according to claim 1, characterized in that: The specific relationship between the predicted value and the measured value of the wave condition and wind condition parameters of the outer port model boundary and the specific relationship between the predicted value and the measured value of the wave condition and wind condition parameters in the port are obtained by drawing scatter plots and deriving them using polynomial fitting.

5. The method for numerically processing waves of a sheltered pier according to claim 1, characterized in that: In the step 2, the mathematical model of the waves in the harbor is set by using the swan wave numerical simulation software, including the model parameter setting and the model terrain file setting. The model parameter setting includes the bottom friction parameter and the breaking parameter, both of which adopt the model recommended values; the model terrain file is generated by using the SMS terrain making software.

6. The method for numerically processing waves of a sheltered pier according to claim 1, characterized in that: The method further includes an updating mechanism, i.e., repeating the process of step 1 and step 3 from time to time, updating the specific relationship between the predicted value and the measured value of the wave condition and wind condition parameters at the boundary of the port model, and the specific relationship between the predicted value and the measured value of the wave condition and wind condition parameters in the port, which is specifically: Cluster analysis of marine environmental changes was performed, and marine environmental changes were divided into calm periods, general change periods, and drastic change periods: During the calm period, continuously accumulating the predicted values ​​and measured values ​​of the wave and wind condition parameters of the historical model boundary outside the port, as well as the predicted values ​​and measured values ​​of the wave and wind condition parameters in the historical port, and repeating the process of step 1 and step 3 every 1 to 3 months; During the general change period, the change range of each parameter is monitored in real time. If the cumulative change range of each parameter exceeds a certain threshold, the process of step 1 and step 3 is immediately repeated; During the period of drastic changes, the process of steps 1 and 3 was repeated every 15 to 30 minutes.

7. The method for numerically processing waves of a sheltered pier according to claim 6, characterized in that: During the general change period, the threshold values ​​of the change amplitudes of various parameters are: wave height changes 0.5~1.2m, and wind speed changes 3~6m / s.

8. The method for numerically processing waves of a sheltered pier according to claim 6, characterized in that: The determination method of the calm period, general change period and drastic change period is as follows: When the wave height is less than 0.3m, the wind speed is less than 3m / s, the current speed is weak, and the water temperature and salinity remain relatively constant, the sea area is judged to be in a calm period; When the wave height is between 0.3 and 0.6 m, the wind speed is between 3 and 6 m / s, the current speed is less than 0.5 knots, the water temperature is between 15 and 18 °C, and the salinity is between 34‰ and 35‰, the sea area is judged to have entered the general change period; When the wave height is greater than 1.5m, the wind speed is greater than 10m / s, the current speed is greater than 1 knot, the water temperature changes suddenly by more than 2°C, and the salinity fluctuates by more than 1‰, the sea area is judged to have entered a period of drastic changes.

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