Wave generation-current generation-vibration table combined loading method based on test wave elements

Abstract

The invention discloses a wave generation-flow generation-vibration table combined loading method based on test wave elements, and the method comprises the steps: starting a flow generation device to form a stable flow field, and monitoring the flow velocity uniformity in real time through a flow velocity sensor; starting wave making equipment to generate a target wave, synchronously acquiring wave crest arrival time through a wave sensor arranged along the wave propagation direction, and calculating a wave period and a wave propagation speed; selecting the wave crest of the wave period of the target characteristic wave, calculating the phase time offset according to the phase of the target characteristic wave, and calculating the propagation time of the target characteristic wave based on the wave propagation speed, the horizontal distance from the wave sensor to the center of the vibration table and the phase time offset; and obtaining the initial loading time of the vibration table, and calculating the final starting time of the vibration table according to the initial loading time of the vibration table and the target characteristic wave propagation time. According to the invention, the loading time sequence and parameters of the vibration table are accurately controlled, and accurate and synchronous loading of waves, ocean currents and vibration is realized.

Description

Technical Field

[0001] The present invention relates to the technical field of hydrodynamic tests, and particularly to a combined loading method of wave generation - current generation - shaking table based on measured wave elements. Background Art

[0002] In hydrodynamic tests, to study the dynamic response and adaptability of ocean engineering structures, it is usually necessary to simulate complex ocean environmental conditions, including various dynamic loading scenarios such as waves, ocean currents, and underwater vibrations. These dynamic conditions are usually realized by wave generators, current generation devices, and underwater shaking tables respectively. However, the existing technologies face many problems in realizing combined loading.

[0003] Currently, there is no effective linkage trigger and coupling control method established between the shaking table and the wave generator, making it difficult to achieve precise synchronous loading of waves and the vibration of the shaking table. This lack of technology directly leads to the difficulty in maintaining consistency in the time and space of the effects of wave and vibration loading during the test, limiting the dynamic accuracy of real ocean environment simulation. In addition, the existing methods also fail to provide an accurate combined loading method for different working conditions, lacking effective control of the complex coupling relationship between waves, ocean currents, and vibrations, and the authenticity and controllability of test results are greatly limited.

[0004] Furthermore, under the action of the flow field, the elements of waves (such as wave height, wave speed, etc.) will change, and the wave parameters obtained by theoretical calculation are difficult to accurately reflect the actual wave characteristics in the test. Therefore, how to measure the actual wave elements in real time through sensors to correct the loading parameters has become an innovative requirement in the current combined loading method.

[0005] Therefore, proposing a combined loading method of wave generation - current generation - shaking table based on measured wave elements to solve the difficulties existing in the prior art is an urgent problem for those skilled in the art. Summary of the Invention

[0006] The purpose of the present invention is to provide a combined loading method of wave generation - current generation - shaking table based on measured wave elements, accurately control the loading timing and parameters of the shaking table, achieve precise synchronous loading of waves, ocean currents, and vibrations, and avoid the problems of coupling failure and asynchronous loading in the prior art.

[0007] To achieve the above purpose, the present invention provides the following solution:

[0008] A combined loading system of wave generation - current generation - shaking table based on measured wave elements, comprising:

[0009] Wave-making equipment, current-making equipment and underwater shaking table are used to generate target waves and a stable flow field, as well as simulate ground motions and mechanical vibrations; at least two groups of wave sensors and flow velocity sensors; a control system is used to collect sensor data in real time, calculate loading parameters, and synchronously trigger the combined loading of multiple devices.

[0010] A combined loading method of wave-making - current-making - shaking table based on measured wave elements is applied to the above-mentioned combined loading system of wave-making - current-making - shaking table based on measured wave elements, and includes the following steps:

[0011] S1. Start the current-making equipment to form a stable flow field, and monitor the flow velocity uniformity in real time through the flow velocity sensor;

[0012] S2. Start the wave-making equipment to generate target waves, synchronously collect the wave crest arrival times through wave sensors arranged along the wave propagation direction, and calculate the wave period and wave propagation speed;

[0013] S3. Select the wave crest of the wave period where the target characteristic wave is located, calculate the phase time offset according to the phase of the target characteristic wave, and calculate the propagation time of the target characteristic wave based on the wave propagation speed, the horizontal distance from the wave sensor to the center of the shaking table, and the phase time offset;

[0014] S4. Obtain the initial loading time of the shaking table, and calculate the final starting time of the shaking table according to the initial loading time of the shaking table and the propagation time of the target characteristic wave, so as to realize the synchronous coupling loading of the target characteristic wave and the motion of the shaking table.

[0015] Preferably, in S2, synchronously collecting the wave crest arrival times through wave sensors arranged along the wave propagation direction and calculating the wave period and wave propagation speed specifically includes:

[0016] Arrange two groups of wave sensors along the wave propagation direction, namely wave sensor one and wave sensor two. The horizontal distance between the two groups of wave sensors is L. Start synchronously collecting wave data from t = 0. Select the same characteristic wave crest, and record its absolute time t1 when it arrives at wave sensor one and its absolute time t2 when it arrives at wave sensor two. Calculate the wave period T according to the time difference T = t2 - t1 of the wave crest arriving at different wave sensors; calculate the wave propagation speed v according to the time difference between the two groups of wave sensors and the known distance L:

[0017]

[0018] Among them, Δt is the time difference of the wave crest arriving at different wave sensors, and Δt = t2 - t1.

[0019] Preferably, in S3, calculating the propagation time of the target characteristic wave based on the wave propagation speed, the horizontal distance from the wave sensor to the center of the shaking table, and the phase time offset specifically includes:

[0020] Calculate the time t for the target wave to propagate from Wave Sensor 2 to the shaking table based on the wave propagation speed and the horizontal distance from Wave Sensor 2 to the center of the shaking table. D :

[0021]

[0022] Where D is the horizontal distance from Wave Sensor 2 to the center of the shaking table; calculate the propagation time t of the target characteristic wave. wave :

[0023] t wave = t3 + t D + t phase

[0024] Where t3 is the absolute time when the wave crest reaches Wave Sensor 2, and t phase is the phase time offset of the target characteristic wave.

[0025] Preferably, in S4, the initial loading time of the shaking table is determined by the seismic waveform model and the control system, and is calculated according to the seismic wave loading parameters, in combination with the acceleration-time curve and the dynamic response characteristics of the shaking table.

[0026] Preferably, in S4, according to the initial loading time of the shaking table and the propagation time of the target characteristic wave, the formula for calculating the final start time of the shaking table is as follows:

[0027] t start = t wave - t eq

[0028] Where t start is the start time of the shaking table, and t eq is the initial loading time of the shaking table.

[0029] The present invention also provides a non-transitory computer-readable storage medium, on which a computer program is stored, and when the computer program is executed by a processor, it implements a wave-making - current-making - shaking table combined loading method based on test wave elements as described in any one of the above.

[0030] According to the specific embodiments provided by the present invention, the following technical effects are disclosed:

[0031] (1) By measuring the wave propagation characteristics in real time, the present invention accurately controls the loading timing and parameters of the shaking table, realizes the precise synchronous loading of waves, ocean currents and vibrations, and avoids the problems of coupling failure and asynchronous loading in the prior art; this method can more realistically restore the ocean environment characteristics under multiple external forces, and by accurately coupling waves and vibrations, it simulates a more realistic dynamic response of the ocean environment, enhancing the physical fidelity of the test.

[0032] (2) Through the real-time feedback adjustment mechanism, the present invention reduces the test debugging time and error, improves the stability and reliability of the test results, and significantly improves the test efficiency; by measuring the actual wave elements under the influence of the flow field, the problem that the traditional method cannot accurately capture the actual characteristics of the waves is solved, and the accuracy of wave loading is improved; this method is not only applicable to the dynamic response test of ships and ocean structures, but also can be used in various complex marine environment simulation tests such as the adaptability assessment of deep-sea equipment and the anti-wave and anti-wind design of offshore platforms. By calculating the phase time offset of the target characteristic wave, any target wave can be coupled with the shaking table, and at the same time, the wave crest and wave trough of the wave are superimposed on the peak value of the shaking table vibration, and the coupling and superposition of any wave point and the shaking table vibration are achieved. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required to be used in the embodiments. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on these drawings.

[0034] Figure 1 It is a schematic flow chart of a combined wave-making, current-making and shaking table loading method based on measured wave elements provided by the present invention;

[0035] Figure 2 It is an example diagram of calculating the time difference according to the time when the sensor is reached in the present invention;

[0036] Figure 3 It is a schematic diagram of the phase time offset calculated in the present invention;

[0037] Figure 4 It is a plan layout diagram of the combined loading test site in the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0038] The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the drawings in the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, rather than all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the scope of protection of the present invention.

[0039] To make the above objects, features and advantages of the present invention more obvious and understandable, the present invention will be further described in detail below with reference to the drawings and specific embodiments.

[0040] As Figure 2As shown in the figure, a combined wave-making - current-making - shaking table loading system based on test wave elements provided by the present invention includes:

[0041] A wave-making device, a current-making device and an underwater shaking table, which are used to generate target waves and a stable flow field, and simulate ground motion and mechanical vibration; at least two groups of wave sensors and flow velocity sensors; a control system, which is used to collect sensor data in real time, calculate loading parameters, and synchronously trigger the combined loading of multiple devices.

[0042] As Figure 1 shown, a combined wave-making - current-making - shaking table loading method based on test wave elements, which is applied to the above-mentioned combined wave-making - current-making - shaking table loading system based on test wave elements, includes the following steps:

[0043] S1. Start the current-making device to form a stable flow field, and monitor the flow velocity uniformity in real time through the flow velocity sensor;

[0044] S2. Start the wave-making device to generate target waves, synchronously collect the wave crest arrival time through the wave sensors arranged along the wave propagation direction, and calculate the wave period and wave propagation speed;

[0045] S3. Select the wave crest of the wave period where the target characteristic wave is located, calculate the phase time offset according to the phase of the target characteristic wave, and calculate the propagation time of the target characteristic wave based on the wave propagation speed, the horizontal distance from the wave sensor to the center of the shaking table and the phase time offset;

[0046] S4. Obtain the initial loading time of the shaking table, and calculate the final starting time of the shaking table according to the initial loading time of the shaking table and the propagation time of the target characteristic wave, so as to realize the synchronous coupling loading of the target characteristic wave and the motion of the shaking table.

[0047] Specifically, S1 includes: starting the current-making device, setting the target flow velocity and direction to form a stable flow field; using the flow velocity sensor to monitor the flow field state to ensure that the flow velocity is uniform and stable.

[0048] Further, in S2, synchronously collecting the wave crest arrival time through the wave sensors arranged along the wave propagation direction and calculating the wave period and wave propagation speed specifically include:

[0049] Start the wave-making device, and the wave-making device is specifically set as a wave generator. Set the starting moment of the wave generator as t = 0 and start to generate target waves; arrange two groups of wave sensors along the wave propagation direction, namely wave sensor one and wave sensor two. The horizontal distance between the two groups of wave sensors is L, and start to synchronously collect wave data from the moment of t = 0; select the same characteristic wave crest, and record its absolute time t1 when it arrives at wave sensor one and its absolute time t2 when it arrives at wave sensor two; calculate the wave period T according to the time difference T = t2 - t1 of the wave crest arriving at different wave sensors asFigure 2 As shown in the figure; according to the time difference between two groups of wave sensors and the known distance L, calculate the wave propagation speed v:

[0050]

[0051] Among them, Δt is the time difference for the wave crest to reach different wave sensors, and Δt = t2 - t1.

[0052] Furthermore, to achieve the coupled loading of the target characteristic wave and the specific vibration position of the shaking table, it is necessary to calculate the time for the target characteristic wave to propagate to the center of the shaking table. The specific steps are as follows:

[0053] Select the wave crest of the wave period where the target characteristic wave is located, and record the absolute time t3 when the wave crest reaches the second wave sensor;

[0054] Calculate the phase time offset t of the target characteristic wave within the wave period phase According to the phase φ (range: [0, 2π]) of the target characteristic wave within the wave period, calculate the time offset of the target characteristic wave relative to the wave crest as Figure 3 shown as:

[0055]

[0056] Among them: T is the wave period, calculated by T = t2 - t1; φ represents the phase position of the target characteristic wave within the wave period (such as the wave trough φ1 = π, the quarter wave period φ2 = π / 2, etc.).

[0057] According to the wave propagation speed and the horizontal distance from the second wave sensor to the center of the shaking table, calculate the time t for the target wave to propagate from the second wave sensor to the shaking table D :

[0058]

[0059] Among them, D is the horizontal distance from the second wave sensor to the center of the shaking table; calculate the time t for the target characteristic wave to propagate to the center of the shaking table wave is:

[0060] t wave = t3 + t D + t phase

[0061] Among them, t3 is the absolute time when the wave crest reaches the second wave sensor, and t phase is the phase time offset of the target characteristic wave.

[0062] Furthermore, when the shaking table executes ground motion, its motion characteristics are determined by the seismic waveform (such as the acceleration-time curve). The shaking table requires a specific time t eqTo complete the process from startup to achieving the target motion characteristics, the calculation method is as follows:

[0063] In S4, the specific value of the initial loading time of the shaking table is determined by the seismic waveform model and the control system, and is calculated according to the seismic wave loading parameters, in combination with the acceleration-time curve and the dynamic response characteristics of the shaking table.

[0064] Furthermore, in order to achieve synchronous loading of the specific motion target of the shaking table and the target characteristic wave, in S4, according to the initial loading time of the shaking table and the propagation time of the target characteristic wave, the formula for calculating the final startup time of the shaking table is as follows:

[0065] t start =t wave -t eq

[0066] where, t start is the startup time of the shaking table, and t eq is the initial loading time of the shaking table.

[0067] In a specific embodiment, the dynamic response performance of a certain new deep-sea platform under the combined action of waves, ocean currents and vibrations is evaluated. The settings are as follows:

[0068] 1. Test site: A hydrodynamic test pool equipped with wave-making, current-making and shaking table equipment, 50 meters long, 20 meters wide and 3 meters deep.

[0069] Equipment configuration: Wave-making equipment: A linear wave maker with a maximum wave height of 1 meter and a frequency range of 0.5 Hz to 2 Hz.

[0070] Current-making equipment: The flow velocity range is 0.1 m / s to 1 m / s, and the direction is adjustable.

[0071] Underwater shaking table: The load capacity is 2 tons, the displacement range is ±50 mm, and the frequency range is 0.1 Hz to 2 Hz.

[0072] Sensors: 2 groups of wave sensors are installed 5 meters and 15 meters away from the wave maker respectively, with a horizontal spacing of 10 meters.

[0073] Control system: Used to control the loading programs of the wave-making, current-making and shaking table and data acquisition.

[0074] 2. Test steps

[0075] Current-making loading: Start the current-making equipment, set the target flow velocity to 0.4 m / s, and the direction is the same as the wave-making direction; start the flow velocity sensor to monitor the flow velocity state in real time to ensure that the flow velocity is uniform and stable; after the flow field is stable, lock the parameters and record the flow velocity distribution data.

[0076] Wave Loading and Wave Velocity Measurement: Start the wave-making equipment to generate target waves, set the wave height to 0.6 m and the period to 2 s.

[0077] Real-time data acquisition by wave sensors: Record the time t1 = 3.5 s when the characteristic wave peak reaches wave sensor 1; record the time t2 = 5.0 s when the characteristic wave peak reaches wave sensor 2.

[0078] Calculate the wave velocity:

[0079]

[0080] The wave period T = 1.5 s.

[0081] Calculation of the propagation time of the target characteristic wave: Select the wave peak in the period where the characteristic wave is located and record the time t3 = 7.0 s when it reaches wave sensor 2.

[0082] Calculate the phase time offset t of the target characteristic wave phase , assuming the target wave is a half-period wave (phase φ = π):

[0083]

[0084] Calculate the time t for the target wave to propagate to the center of the shaking table wave

[0085]

[0086] Calculation of the loading time of the shaking table: The required loading time t of the shaking table eq is 2.0 s.

[0087] Calculate the starting time of the shaking table

[0088] t start = t wave - t eq = 11.0 - 2.0 = 9.0 s

[0089] Start the shaking table at time t = 9.0 s to load the earthquake ground motion simulation.

[0090] Execution of the combined loading test: The control system starts the wave-making, current-making equipment and the shaking table simultaneously according to the set parameters to ensure the synchronous execution of the three dynamic loadings. The data acquisition equipment records data such as wave height, flow velocity, and vibration acceleration during the whole test.

[0091] The present invention also provides a non-transitory computer-readable storage medium, on which a computer program is stored. When the computer program is executed by a processor, it implements a combined wave-making-current-making-shaking table loading method based on test wave elements as described in any one of the above.

[0092] Through the description of the above embodiments, those skilled in the art can clearly understand that each embodiment can be implemented by means of software plus a necessary general hardware platform, and of course, it can also be implemented by hardware. Based on such an understanding, the essence of the above technical solution, or the part that contributes to the prior art, can be embodied in the form of a software product. This computer software product can be stored in a computer-readable storage medium, such as ROM / RAM, magnetic disk, optical disk, etc., and includes several instructions for causing a computer device (which can be a personal computer, a server, or a network device, etc.) to execute the methods described in each embodiment or some parts of the embodiments.

[0093] In this article, specific examples are used to elaborate on the principles and embodiments of the present invention. The description of the above embodiments is only used to help understand the method of the present invention and its core idea; at the same time, for those of ordinary skill in the art, according to the idea of the present invention, there will be changes in the specific implementation manners and application scopes. In summary, the content of this specification should not be construed as a limitation to the present invention.

Claims

1. A combined wave-making, current-making and shaking table loading system based on test wave elements, characterized in that Including: A wave-making device, a current-making device and an underwater shaking table, which are used to generate target waves and a stable flow field, as well as simulate ground motions and mechanical vibrations; at least two groups of wave sensors and flow velocity sensors; a control system, which is used to collect sensor data in real time, calculate loading parameters, and synchronously trigger the combined loading of multiple devices.

2. A combined wave-making, current-making and shaking table loading method based on test wave elements, which is applied to the combined wave-making, current-making and shaking table loading system based on test wave elements described in claim 1, and is characterized in that, Including the following steps: S1. Start the current-making device to form a stable flow field, and use the flow velocity sensor to monitor the flow velocity uniformity in real time; S2. Start the wave-making device to generate target waves, synchronously collect the wave crest arrival time through the wave sensors arranged along the wave propagation direction, and calculate the wave period and wave propagation velocity; S3. Select the wave crest of the wave period where the target characteristic wave is located, calculate the phase time offset according to the phase of the target characteristic wave, and calculate the propagation time of the target characteristic wave based on the wave propagation velocity, the horizontal distance from the wave sensor to the center of the shaking table, and the phase time offset; S4. Obtain the initial loading time of the shaking table, and calculate the final starting time of the shaking table according to the initial loading time of the shaking table and the propagation time of the target characteristic wave, so as to realize the synchronous coupling loading of the target characteristic wave and the motion of the shaking table.

3. A combined loading method of wave generation - current generation - shaking table based on test wave elements according to claim 1, characterized in that, In S2, the synchronous collection of the wave crest arrival time through the wave sensors arranged along the wave propagation direction and the calculation of the wave period and wave propagation velocity specifically include: Arrange two groups of wave sensors along the wave propagation direction, namely wave sensor one and wave sensor two. The horizontal distance between the two groups of wave sensors is L. Start to synchronously collect wave data from t = 0. Select the same characteristic wave crest, and record its absolute time t1 when it arrives at wave sensor one and its absolute time t2 when it arrives at wave sensor two. Calculate the wave period T according to the time difference T = t2 - t1 of the wave crest arriving at different wave sensors. Calculate the wave propagation velocity v according to the time difference between the two groups of wave sensors and the known distance L: Wherein, Δt is the time difference of the wave crest arriving at different wave sensors, and Δt = t2 - t1.

4. A wave-making - current-making - shaking table combined loading method based on test wave elements according to claim 1, characterized in that, In S3, the calculation of the propagation time of the target characteristic wave based on the wave propagation velocity, the horizontal distance from the wave sensor to the center of the shaking table, and the phase time offset specifically includes: Calculate the time t for the target wave to propagate from Wave Sensor 2 to the shaking table based on the wave propagation speed and the horizontal distance from Wave Sensor 2 to the center of the shaking table D : Where D is the horizontal distance from the second wave sensor to the center of the vibration table; calculate the propagation time t of the target characteristic wave wave : t wave = t3 + t D + t phase Among them, t3 is the absolute time when the wave crest reaches the second wave sensor, and t phase is the phase time offset of the target characteristic wave.

5. A combined loading method of wave generation - current generation - shaking table based on test wave elements according to claim 1, characterized in that, The initial loading time of the shaking table in S4 is determined by the seismic waveform model and the control system, and is calculated according to the seismic wave loading parameters, combined with the acceleration-time curve and the dynamic response characteristics of the shaking table.

6. The combined loading method of wave generation - current generation - shaking table based on test wave elements according to claim 4, characterized in that In S4, the formula for calculating the final starting time of the shaking table according to the initial loading time of the shaking table and the propagation time of the target characteristic wave is as follows: t start = t wave - t eq Among them, t start is the starting time of the shaking table, and t eq is the initial loading time of the shaking table.

7. A non-transitory computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by a processor, it implements a wave-making-current-making-shaking table combined loading method based on test wave elements as described in any one of claims 2 to 6.

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