Test method for measuring navigation parameters of ship in navigable tunnel

Abstract

The invention discloses a test method for measuring navigation parameters of a navigation tunnel ship, which belongs to the technical field of navigation tunnels and comprises the following steps: determining a navigation tunnel model scale according to a model range and test site requirements; according to the navigation tunnel model scale, a test water tank and a ship model are manufactured; installing a navigation element test system and a test data synchronous acquisition system on the ship model; injecting water into the test water tank until the water depth meets the test group requirement, and placing the ship model at the front end of the test water tank; starting the test data synchronous acquisition system, and initializing the navigation element test system in a still water state; determining the main engine power according to the relationship between the still water speed of the ship and the main engine power; the ship model is started based on the host power, the test data synchronous acquisition system is used for acquiring the longitudinal distance data of the ship and the vertical distance data of the stern in real time, and ship navigation parameters such as the ship opposite-shore navigational speed, the ship navigation resistance and the stern sinkage are obtained through calculation.

Description

Technical Field

[0001] The invention belongs to the technical field of navigable tunnels, and in particular relates to a test method for measuring navigation parameters of ships in navigable tunnels. Background Art

[0002] In the design process of navigable tunnels, accurately obtaining the navigation parameters of ships is a key link. At present, although there are some methods for estimating the navigation parameters of ships in general restricted waterways, the cross-sectional coefficient of navigable tunnels is extremely small and the navigation conditions are complex. Therefore, relevant parameters are mainly obtained by ship model tests. The existing ship model test methods mainly include towing methods and motion conversion methods. The towing method uses a trailer-type ship model test pool to keep the trailer towing the ship model in a certain direction and speed; the motion conversion method converts the movement of the ship relative to the water flow into the movement of the water flow relative to the ship, that is, constraining the horizontal movement of the ship and allowing the water flow to move in a certain direction and speed. Both methods can measure the navigation parameters of the ship at a fixed speed.

[0003] However, the cross-section blocking effect in the navigable tunnel is obvious, the ship's navigation resistance increases, the hull sinks, and the actual speed on the other side is significantly lower than that in open waters, and can even drop to about 50%. In addition, due to the influence of ship waves, the ship's navigation speed in the tunnel changes dynamically, and parameters such as navigation resistance and sinking also change dynamically. The existing towing method and motion conversion method cannot simulate this complex dynamic navigation process, and the corresponding parameter measurement method is no longer applicable to the acquisition of dynamic navigation parameters in navigable tunnels. Summary of the invention

[0004] In order to solve the above technical problems, the present invention proposes a test method for measuring navigation parameters of ships in navigable tunnels to solve the problems existing in the above prior art.

[0005] To achieve the above-mentioned object, in a first aspect, the present invention provides a test method for determining navigation parameters of a ship in a navigable tunnel, comprising:

[0006] Determine the scale of the navigation tunnel model according to the navigation tunnel scale and test site requirements;

[0007] According to the scale of the navigation tunnel model, a test water tank and a ship model are manufactured;

[0008] Installing a navigation element test system and a test data synchronization acquisition system on the ship model;

[0009] Fill the test water tank with water until the water depth reaches the test group requirement, and place the ship model at the front end of the test water tank;

[0010] Starting the test data synchronous acquisition system to initialize the navigation element test system in a static water state;

[0011] Determine the main engine power according to the relationship between the ship's still water speed and the main engine power; start the ship model based on the main engine power, and use the test data synchronization acquisition system to collect the ship's longitudinal distance and stern sinking data in real time;

[0012] The ship's navigation parameters are calculated based on the ship's longitudinal distance and stern vertical distance data.

[0013] Preferably, the test water tank is used to simulate the water-passing part of a navigation tunnel and is plastered with cement mortar;

[0014] A movable partition is arranged inside the test water tank, and the width of the test water tank is adjusted by the movable partition.

[0015] Preferably, the hull of the ship model is made of fiberglass, supplemented with lead weights to keep the draft of the model similar to that of the prototype, and is installed with a power system and remotely controlled.

[0016] Preferably, the navigation element testing system includes a laser rangefinder and an underwater ultrasonic rangefinder, the laser rangefinder is installed on the shore wall at one end of the test water tank, and the underwater ultrasonic rangefinder is installed on the stern bottom plate.

[0017] Preferably, the ship navigation element testing system and the test data synchronization acquisition system are interconnected.

[0018] Preferably, the ship navigation parameters include: ship speed to shore, ship navigation resistance and stern sinking amount;

[0019] The ship's speed across the shore is calculated based on the longitudinal distance of the ship;

[0020] The ship's sailing resistance is calculated based on the ship's speed data to the shore;

[0021] The stern sinking amount is calculated through the stern vertical distance.

[0022] Preferably, the formula for calculating the ship's speed across the shore is:

[0023] ;

[0024] Where V is the ship's speed across the shore; Dl n 、Dl n-1 are the nth and n-1th data of the ship's longitudinal distance series respectively; Δt l It is the sampling time interval of the laser rangefinder.

[0025] Preferably, the formula for calculating the ship's sailing resistance is:

[0026] ;

[0027] ;

[0028] ;

[0029] ;

[0030] ;

[0031] ;

[0032] ;

[0033] Among them, R is the ship's navigation resistance, S is the wet surface area of ​​the hull, , L w is the waterline length of the ship, d is the designed draft of the ship, C B is the ship's square coefficient, B is the ship's width (m); Fr h is the water depth Froude number, , L is the length of the ship; K b is the coefficient that characterizes the lateral contraction effect of the tunnel; W is the tunnel width; h is the water depth; a, b, c, d' are regression coefficients.

[0034] Preferably, the formula for calculating the stern sinking amount is:

[0035]

[0036] Where, T is the stern sinking amount; Dv1, Dv n are the first and nth data of the ship vertical distance series respectively; Δt v It is the sampling time interval of the laser rangefinder.

[0037] In a second aspect, the present invention further discloses a computer-readable storage medium having a computer program stored thereon, which implements the steps of the method described in the first aspect when executed by a processor.

[0038] Compared with the prior art, the present invention has the following advantages and technical effects:

[0039] The present invention provides a test method for determining navigation parameters of ships in a navigable tunnel. First, according to the scale of the navigable tunnel and the requirements of the test site, the scale of the navigable tunnel model is determined; according to the scale of the navigable tunnel model, a test water tank is made; according to the scale of the navigable tunnel model, a ship model is made; secondly, a navigation element test system and a test data synchronization acquisition system are installed on the ship model; then, water is poured into the test water tank until the water depth reaches the test group requirement, and the ship model is placed at the front end of the test water tank; further, the test data synchronization acquisition system is started, and the navigation element test system is initialized in a static water state; according to the relationship between the static water speed of the ship and the main engine power, the main engine power is determined; based on the main engine power, the ship model is started, and the ship navigation parameters are obtained by using the test data synchronization acquisition system; finally, the ship longitudinal distance and the stern vertical distance data are collected in real time, and the ship's opposite shore speed, the ship's navigation resistance and the stern sinking amount are calculated by using a calculation formula.

[0040] The present invention can realistically simulate the navigation process of ships in a navigation tunnel prototype, and the tunnel width can be adjusted, and can more effectively reflect the impact of the scale blocking effect of the navigation tunnel on the navigation parameters of ships. Compared with the traditional method, the prediction accuracy of the present invention is higher for obtaining the navigation parameters of ships in the navigation tunnel. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] The drawings constituting a part of the present application are used to provide a further understanding of the present application. The illustrative embodiments and descriptions of the present application are used to explain the present application and do not constitute an improper limitation on the present application. In the drawings:

[0042] Figure 1 A top view of a test device according to an embodiment of the present invention;

[0043] Figure 2 A longitudinal cross-sectional view of a test device according to an embodiment of the present invention;

[0044] Figure 3 A transverse cross-sectional view of a test device according to an embodiment of the present invention;

[0045] Figure 4 This is a schematic diagram of the relationship between the still water speed of a ship and the main engine power according to an embodiment of the present invention;

[0046] Figure 5 This is a schematic diagram of a ship-to-shore speed test result according to an embodiment of the present invention;

[0047] Figure 6 This is a schematic diagram of the sailing resistance test results of an embodiment of the present invention;

[0048] Figure 7 Schematic diagram of ship sinking test results according to an embodiment of the present invention. DETAILED DESCRIPTION

[0049] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application can be combined with each other. The present application will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0050] It should be noted that the steps shown in the flowcharts of the accompanying drawings can be executed in a computer system such as a set of computer executable instructions, and that, although a logical order is shown in the flowcharts, in some cases, the steps shown or described can be executed in an order different from that shown here.

[0051] Embodiment 1

[0052] This embodiment provides a test method for determining navigation parameters of a ship in a navigable tunnel, comprising:

[0053] S1. Determine the model scale according to the navigation tunnel scale and test site requirements. The navigation tunnel model scale is generally L r =20~30.

[0054] S2. Make a test water tank according to the scale of the navigation tunnel model. The length of the test water tank is designed according to the actual navigation tunnel length. The width of the test water tank is designed according to 1.8 times the ship width. The height of the test water tank is equal to the maximum water depth of the test water tank plus 10cm of surplus height and rounded up. Among them, the maximum water depth of the test water tank = the designed draft of the ship + the maximum surplus water depth of 4m.

[0055] Step S2 is an innovative method for determining the initial scale of the tunnel model;

[0056] The test water tank is used to simulate the water-passing part of the navigation tunnel (the closed round arch structure on the top of the tunnel has no effect on the navigation of ships and is not simulated. Only the water-passing part below can be simulated). Cement mortar is used for plastering;

[0057] As an innovative implementation method, a movable partition is arranged inside the sink, so that the width of the sink can be adjusted within a certain range.

[0058] S3, make a ship model according to the scale of the navigable tunnel model, and calibrate the relationship between the ship's still water speed and main engine power in an open water environment with no wind.

[0059] The ship model is processed and installed in geometric scale according to the actual ship line diagram, propeller blade diagram and rudder blade diagram. The hull is made of fiberglass and supplemented with lead weights to keep the draft of the model similar to that of the prototype. A power system is installed and it is remotely controlled.

[0060] S4, install the navigation element test system and the test data synchronization acquisition system.

[0061] The navigation element test system includes a laser rangefinder and an underwater ultrasonic rangefinder. The laser rangefinder is installed on the bank wall at one end of the test tank, and the underwater ultrasonic rangefinder is installed on the stern bottom plate. The ship navigation element test system is interconnected with the test data synchronization acquisition system.

[0062] Figure 1 A top view of the test device of this embodiment;

[0063] Figure 2 is a longitudinal cross-sectional view of the test device of this embodiment;

[0064] Figure 3 It is a transverse cross-sectional view of the test device of this embodiment.

[0065] S5, pour water into the test water tank until the water depth reaches the test group requirement, and place the ship model at the front end of the test water tank.

[0066] S6, start the test data synchronous acquisition system and initialize the navigation element test system in a still water state.

[0067] S7, according to the still water speed of the test group, determine the main engine power, start the ship model, and use the test data synchronization acquisition system to synchronously collect the ship's longitudinal distance and stern sinking data in real time;

[0068] The ship's speed across the shore is calculated using formula (1);

[0069] (1)

[0070] Where V is the ship's speed across the shore; Dl n 、Dl n-1 are the nth and n-1th data of the ship's longitudinal distance series respectively; Δt l It is the sampling time interval of the laser rangefinder.

[0071] The ship's sailing resistance is calculated using formulas (2) to (8);

[0072] (2)

[0073] (3)

[0074] (4)

[0075] (5)

[0076] (6)

[0077] (7)

[0078] (8)

[0079] Where R is the ship's sailing resistance (N), S is the wet surface area of ​​the hull (m 2 ), , L w is the waterline length of the ship (m), d is the designed draft of the ship (m), C B is the ship's square coefficient, B is the ship's width (m); Fr h is the water depth Froude number, , L is the length of the ship (m); K b is the coefficient that characterizes the lateral contraction effect of the tunnel; W is the tunnel width (m); h is the water depth (m); a, b, c, d' are regression coefficients.

[0080] The stern sinking amount is calculated using formula (9):

[0081] (9)

[0082] Where, T is the stern sinking amount; Dv1, Dv n are the first and nth data of the ship vertical distance series respectively; Δt v It is the sampling time interval of the laser rangefinder.

[0083] Compared with the traditional towing method or motion conversion method, the test device in the present invention includes a test water tank, a ship model, and a navigation element testing system, which can truly simulate the navigation process of the ship in the prototype, and the width of the tunnel can be adjusted, which can more effectively reflect the impact of the blocking effect of the navigable tunnel on the navigation parameters of the ship.

[0084] This embodiment provides an application example:

[0085] Input conditions:

[0086] ① The length of the navigation tunnel is 1400m;

[0087] ② The ship size is 130m×16.3m×4.3m (length×width×draft), the waterline length is 123.47m, and the box coefficient is 0.5;

[0088] ③Model scale L r =30

[0089] The prediction results are as follows:

[0090] ① Test tank dimensions: length 46.67m, tank width 1m, tank height 0.38m;

[0091] ② The relationship between ship still water speed and main engine power is shown in Figure 4 ;

[0092] ③ The test results of the ship's speed to the shore, navigation resistance and stern sinking under the test group with a navigation tunnel depth of 6m and a ship's still water speed of 1.5m / s are shown in Figure 5 to Figure 7 .

[0093] Embodiment 2

[0094] This embodiment further discloses a computer-readable storage medium on which a computer program is stored. When the computer program is executed by a processor, the steps of the method described in the first embodiment are implemented.

[0095] The above are only preferred specific implementations of the present application, but the protection scope of the present application is not limited thereto. Any changes or substitutions that can be easily thought of by a person skilled in the art within the technical scope disclosed in the present application should be included in the protection scope of the present application. Therefore, the protection scope of the present application should be based on the protection scope of the claims.

Claims

1. A test method for determining navigation parameters of ships in a navigable tunnel, characterized in that: The following steps are involved: Determine the scale of the navigation tunnel model according to the navigation tunnel scale and test site requirements; According to the scale of the navigation tunnel model, a test water tank and a ship model are manufactured; Installing a navigation element test system and a test data synchronization acquisition system on the ship model; Fill the test water tank with water until the water depth reaches the test group requirement, and place the ship model at the front end of the test water tank; Starting the test data synchronous acquisition system to initialize the navigation element test system in a static water state; Determine the main engine power according to the relationship between the ship's still water speed and the main engine power; start the ship model based on the main engine power, and use the test data synchronization acquisition system to collect the ship's longitudinal distance and stern vertical distance data in real time; The ship's navigation parameters are calculated based on the ship's longitudinal distance and stern vertical distance data.

2. The method according to claim 1, characterized in that The test water tank is used to simulate the water-passing part of the navigation tunnel and is plastered with cement mortar; A movable partition is arranged inside the test water tank, and the width of the test water tank is adjusted by the movable partition.

3. The method according to claim 1, characterized in that The hull of the ship model is made of fiberglass and supplemented with lead weights to keep the draft of the model similar to that of the prototype. A power system is installed and it is remotely controlled.

4. The method according to claim 1, characterized in that: The navigation element test system comprises a laser rangefinder and an underwater ultrasonic rangefinder. The laser rangefinder is installed on the bank wall at one end of the test water tank, and the underwater ultrasonic rangefinder is installed on the stern bottom plate.

5. The method according to claim 1, characterized in that The ship navigation element testing system is connected to the test data synchronization acquisition system.

6. The method according to claim 1, characterized in that Said ship navigation parameters include: ship speed to the shore, ship navigation resistance and stern sinking amount; The ship's speed across the shore is calculated based on the longitudinal distance of the ship; The ship's sailing resistance is calculated based on the ship's speed data to the shore; The stern sinking amount is calculated through the stern vertical distance.

7. The method according to claim 6, characterized in that The formula for calculating the ship's speed across the shore is: ； Where V is the ship's speed across the shore; Dl n 、Dl n-1 are the nth and n-1th data of the ship's longitudinal distance series respectively; Δt l It is the sampling time interval of the laser rangefinder.

8. The method according to claim 6, characterized in that The formula for calculating the ship's sailing resistance is: ； ； ； ； ； ； ； Among them, R is the ship's navigation resistance, S is the wet surface area of ​​the hull, , L w is the waterline length of the ship, d is the designed draft of the ship, C B is the ship's square coefficient, B is the ship's width (m); Fr h is the water depth Froude number, , L is the length of the ship; K b is the coefficient that characterizes the lateral contraction effect of the tunnel; W is the tunnel width; h is the water depth; a, b, c, d' are regression coefficients.

9. The method according to claim 6, characterized in that The formula for calculating the stern sinking is: Where, T is the stern sinking amount; Dv1, Dv n are the first and nth data of the ship vertical distance series respectively; Δt v It is the sampling time interval of the laser rangefinder.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of the method according to any one of claims 1 to 9 are implemented.

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