CN116341424A - Comprehensive calculation method for water flow force acting on ship - Google Patents
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Abstract
The invention discloses a comprehensive calculation method of water flow force acting on a ship, which belongs to the technical field of port and channel engineering and comprises the following steps: determining main parameters required by calculation, including design water level, design mud elevation, water flow velocity, vertical line length, width, ship draft corresponding to ship loading degree, ship waterline length and ship square coefficient; judging the directions of the transverse component force, the longitudinal component force and the deflection moment of the water flow force, and determining the flow direction angle of the water flow and the longitudinal axis of the ship; calculating the designed water depth; and thirdly, calculating a transverse component of the water flow force acting on the ship, a longitudinal component of the water flow force acting on the ship and a deflection moment of the water flow force acting on the ship. The calculation method solves the problems of inconvenience in consulting the graph, small calculation result and the like in the traditional method, thereby improving the accuracy and the practicability of water flow force calculation in port engineering.
Description
Technical Field
The invention belongs to the technical field of port and channel engineering, and particularly relates to a comprehensive calculation method of water flow force acting on a ship.
Background
Along with the continuous improvement of the technical level of coastal port construction in China and the development of the enlargement and specialization of ships in the world, wharfs also show the trend of enlargement and deep hydration. A number of large open deepwater terminals such as ocean mountain ports, ningbo ports, zhoushan ports and the like have been built at present. However, the moored waters of open deepwater wharfs are subjected to complex natural environmental conditions such as wind, waves, currents, etc. In addition, the large ship is large in size, deep in draft and high in superstructure, so that under the action of wind, waves and currents, the stress area is large, and the motion response of the ship, the mooring force of the ship and the impact force are increased. The excessive ship movement amplitude can influence the normal loading and unloading operation of the wharf, for example, the generated ship impact force and mooring force are too large, and cable breakage accidents are easy to cause, so that serious threat is formed to the safe production of the wharf and the ship. Therefore, in dock design, the ship load is an important consideration, and reasonable determination of the ship load is important to ensure safe operation of the dock.
In ports where ships are built in islands, the water flow force is an important component of the ship load, especially in situations where the waves are somewhat covered and attenuated. The influence on the ship operation and mooring safety increases because the water flow direction in the island group is rapid and greatly changed. For example, in a certain harbor area of the mountain harbor in China, cable breakage accidents have occurred, wherein water flow is an important accident factor.
Many scholars at home and abroad research the water flow force acting on the ship and obtain a certain research result. These achievements are applied in international organization and in guidelines or standard specifications of various countries, including the "mooring facility guidelines" of the international maritime forum (OCIMF) of petroleum companies, the "maritime building headquarters" of the united kingdom, the "Design of Marine Facilities" ASCE in the united states, the Third Edition "of the united states department of defense design manual (UFC), the japanese standard (OCDI) and the current" harbour engineering load specifications "of our country (JTS 144-1-2010). However, there is a certain difference in water flow force calculated using the standard specifications of these countries.
At present, in the internationally common water flow force calculation method, the water flow force is generally decomposed into transverse component force perpendicular to the longitudinal axis of the ship
Longitudinal component parallel to the longitudinal axis of the ship +.>
And the deflection moment generated by the action of the water flow on the ship>
The general formula for calculating the water flow force is as follows:
water flow force transverse component:
（1）
longitudinal component of water flow force:
（2）
deflection moment:
（3）
or:
（4）
wherein:
-the coefficient of the lateral component of the water flow force; />
-the longitudinal component coefficient of the water flow force; />
-a hydraulic deflection torque coefficient; />
-water flow force eccentricity coefficient; />
-water density; />
-water flow rate; />
-the vertical line of the vessel is long; />
-a vessel draft corresponding to the vessel loading.
From the above formula, it is known that under the condition of knowing the ship scale, the water flow velocity and the water flow direction, the water flow force is calculated by taking the water flow force transverse component coefficient, the water flow force longitudinal component coefficient, the water flow force deflection moment coefficient, the water flow force eccentric coefficient and other coefficients into consideration. These coefficients are related to factors such as the ship type, relative water depth (water depth/ship draft or ship draft/water depth), and angle of flow (angle of water flow from the longitudinal axis of the ship).
The relationship charts of transverse component coefficients and longitudinal component coefficients of water flow force, flow direction angles and relative water depths of tankers and LNG ships under different loading degrees are provided in guidelines and standard specifications at home and abroad. However, for other ship types such as container ships, etc., no corresponding data is given. For example, the OCIMF "mooring facility guidelines" provides data for tankers and LNG vessels, and the British "general marine architecture guidelines" only contains plots of the transverse component coefficients of water flow versus angle for dry cargo vessels, tankers and container vessels under deep water conditions, and provides a map of correction coefficients for the effect of relative water depths, but does not indicate vessel loading and does not contain other vessel types such as LNG vessels. Similarly, the us ASCE Design of Marine Facilities, third Edition and japanese specifications also provide graphs of the transverse component coefficients of water flow force as a function of direction angle and relative water depth, but do not specify the ship type and its loading.
In addition, in China, the port engineering load Specification has some defects in the calculation method. First, the ship type is not specified; secondly, when the flow direction angle of the water flow is more than or equal to 0 degree and less than 15 degrees or more than or equal to 165 degrees and less than or equal to 180 degrees, the transverse component force coefficient of the water flow force is the same, which is not in accordance with the actual situation; thirdly, when the included angle between the water flow direction and the longitudinal axis of the ship is 90 degrees, the calculated transverse component force is 0, and the longitudinal component force is maximum, contrary to common knowledge, in fact, in this case, the transverse component force should reach the maximum value, and the longitudinal component force should be 0; fourth, the relative water depth range in the current calculation method is 1.1-1.5, and corresponding data is not provided for the case that the water depth/ship draft is greater than 1.5; finally, the results of the calculations are significantly smaller than the international standard specifications and test results, which are indicated in some published papers.
The method for determining the component force coefficient of the water flow force is basically described by a relation graph or a table, and if the influence of various ship types and different loading degrees is considered, a large number of relation graphs and tables are needed for investigation, so that the method is difficult to use and inconvenient to use. Meanwhile, the water flow calculated by adopting the standard specifications of each country also has certain difference, and the calculation result of the current specification of China is obviously smaller than the international standard specification and test result, and the defects still exist, so how to more reasonably determine the water flow used on the ship is one of the key problems to be solved in the technical field of the current port channel engineering.
Disclosure of Invention
Aiming at the problems existing in the prior art, the invention provides a comprehensive calculation method for water flow force acting on a ship, which solves the problems of inconvenience and inaccuracy in calculation of water flow force components acting on the ship in the port engineering field.
The invention is realized in such a way that a comprehensive calculation method of water flow force acting on a ship is characterized in that: the method comprises the following steps:
determining main parameters required by calculation, including design water level, design mud elevation, water flow velocity, vertical line length, width, ship draft corresponding to ship loading degree, ship waterline length and ship square coefficient;
judging the directions of the transverse component force, the longitudinal component force and the deflection moment of the water flow force, and determining the flow direction angle of the water flow and the longitudinal axis of the ship; calculating the designed water depth;
and thirdly, calculating a transverse component of the water flow force acting on the ship, a longitudinal component of the water flow force acting on the ship and a deflection moment of the water flow force acting on the ship.
In the above technical solution, it is preferable that the transverse component of the water flow force acting on the ship is
，/>
The calculation is performed according to the following formula:
in the method, in the process of the invention,
-the coefficient of the lateral component of the water flow force;
In the above technical solution, it is preferable that the water flow force transverse component coefficient
The calculation is performed according to the following formula:
in the method, in the process of the invention,
d-design water depthdDesign water level-design mud level elevation;
In the above technical solution, it is preferable that the longitudinal component of the water flow force acting on the ship
，/>
The calculation is performed according to the following formula:
in the method, in the process of the invention,
-a longitudinal component of force generated by the shape resistance;
In the above-described aspect, it is preferable that the longitudinal component force generated by the shape resistance force
The calculation is performed according to the following formula:
in the method, in the process of the invention,
-a longitudinal shape drag coefficient of the vessel;
design water depth asd=Design water level-design mud level elevation, whend/D≤1.5，
When =0.27d/D＞1.5，
=0.17。
In the above-described aspect, it is preferable that the frictional resistance generates a longitudinal component force
The calculation is performed according to the following formula:
in the method, in the process of the invention,
-coefficient of friction of the hull;
In the above technical solution, it is preferable that the friction resistance coefficient of the hull
The calculation is performed according to the following formula:
in the method, in the process of the invention,
-reynolds number of the water flow acting on the vessel;
In the above technical solution, it is preferable that the Reynolds number of the water flow acting on the ship
The calculation is performed according to the following formula:
in the method, in the process of the invention,
-water flow rate;
In the above technical solution, it is preferable that the wet surface area below the waterline of the ship
The calculation is performed according to the following formula:
in the method, in the process of the invention,
-long waterline of the vessel;
In the above-described solution, it is preferable that the water flow force acting on the ship deflects the moment
，/>
The calculation is performed according to the following formula:
in the method, in the process of the invention,
-eccentricity factor;
The invention has the advantages and effects that:
according to the comprehensive calculation method for the water flow force acting on the ship, provided by the invention, the influence of different types of ship types on the water flow force is comprehensively considered, and the load condition of the ship under the action of the water flow can be more accurately calculated by establishing the relation between the characteristic coefficients of different ship types and the water flow force. Compared with the inconvenience of consulting a large number of different graphs when using the universal standard, the method provides a more convenient and efficient way for calculating the water flow force component by simplifying the calculation process.
Through verification, the result obtained by the method is basically consistent with the actual test result, and the difference is smaller than the calculation result of the international main standard specification. Compared with the existing calculation method in China, the calculation method provided by the invention can more accurately estimate the water flow force, and makes up the defect of the existing method in the aspect of water flow force calculation.
The calculation method provided by the invention can be used for more scientifically evaluating the load condition of the ship brought by the water flow in the port, thereby being beneficial to reasonably designing the port and formulating an effective ship operation strategy. In addition, the calculation method of the invention can be widely applied to the fields of ship design, port engineering, navigation safety and the like, and has wide application prospect and economic benefit.
In conclusion, the calculation method provided by the invention has remarkable advantages and practical application value in the technical field of port channel engineering, can solve the load problem of the ship under the action of water flow, provides scientific technical support for reasonable design of port engineering and ship operation safety, has wide application potential in the fields of ship design, port engineering, navigation safety and the like, and is expected to generate positive social and economic benefits in the related fields.
Drawings
FIG. 1 is a cross-sectional view of a ship berthing dock front in an embodiment of the present invention;
FIG. 2 is a schematic view of the direction of flow angle and water flow direction when the ship is port;
FIG. 3 is a schematic view of the direction of flow angle and direction of water flow when starboard flows;
FIG. 4 is a graph showing the comparison between the calculated result and the test result of the horizontal component of the water flow force in the embodiment of the invention;
FIG. 5 is a graph showing the comparison between the calculated results and the test results of the longitudinal component of the water flow force in the embodiment of the invention;
FIG. 6 is a graph showing the comparison between the calculated results and the test results of the hydraulic deflection moment in the embodiment of the present invention;
FIG. 7 is a graph showing the comparison between the calculation result of the horizontal component of the water flow force and the international standard calculation result in the embodiment of the present invention;
FIG. 8 is a graph comparing the calculation result of the longitudinal component of the water flow force with the international standard calculation result in the embodiment of the present invention;
FIG. 9 is a graph comparing the calculated results of the deflection moment of the water flow force with the calculated results of the international standard in the embodiment of the present invention;
FIG. 10 is a flow chart of a method in an embodiment of the invention.
Detailed Description
The present invention will be described in further detail with reference to the following examples in order to make the objects, technical solutions and advantages of the present invention more apparent. It should be understood that the specific embodiments described herein are for purposes of illustration only and are not intended to limit the scope of the invention.
In order to solve the problems of inconvenience and inaccuracy in calculation of water flow force components acting on ships in the field of port engineering, the invention particularly provides a comprehensive calculation method of water flow force acting on ships. For further explanation of the structure of the present invention, the detailed description is as follows in connection with the accompanying drawings:
a comprehensive calculation method of water flow force acting on a ship comprises the following steps:
step one, determining main parameters required by calculation, including design water level, design mud level elevation and water flow velocity
Vertical line length of ship->
Ship width->
Ship draft corresponding to the ship loading level +.>
Ship waterline length->
And square coefficient of ship>
。
Judging the directions of the transverse component force, the longitudinal component force and the deflection moment of the water flow force, and determining the flow direction angle of the water flow and the longitudinal axis of the ship; and calculating the designed water depth. That is, whether the water flow flows from the port side or the starboard side of the ship is analyzed, and the flow direction angle of the water flow and the longitudinal axis of the ship, the transverse component of the water flow force, the longitudinal component of the water flow force and the direction of the deflection moment of the water flow force are determined. Design water depth asd，dDesign water level-design mud level elevation.
And thirdly, calculating a transverse component of the water flow force acting on the ship, a longitudinal component of the water flow force acting on the ship and a deflection moment of the water flow force acting on the ship.
The transverse component of the water flow force acting on the ship is
，/>
The calculation is performed according to the following formula:
in the method, in the process of the invention,
-the coefficient of the lateral component of the water flow force; />
-Water tightness (t/m) 3 ）；/>
-water flow velocity (m/s); />
-the vertical line length (m) of the vessel; />
-a vessel draft (m) corresponding to the vessel loading.
Setting a ship type coefficient:
the method comprises the steps of establishing a physical model test study of water flow force acting on a ship, wherein a physical model is mainly designed according to geometric similarity and gravity similarity criteria, and ensuring the reliability and the practicability of the model by using the two criteria.
The geometric scale, shape, draft and other data of the ship model in the physical model are obtained according to a certain scale-reducing proportion according to a ship model diagram. The test respectively measures various ship type data, and the transverse force of the bow, the transverse force of the stern, the longitudinal force and the moment born by the ship model under the conditions of different draft and different water depths respectively and reversely calculates the transverse component force coefficient of the water flow force according to the data
Longitudinal component force coefficient of water flow force->
Eccentric coefficient of water flow force +.>
And analyzing each coefficient and ship type, flow direction angle +.>
Design depth of waterdShip draft corresponding to the ship loading level +.>
A functional relationship between them.
Coefficient of transverse component of force for water flow
To integrate the effects of different ship types, the coefficients +.>
And->
Values. And by testing different ship types and fitting out the function curve, the function curve fitted by each type of tested ship type is well fitted with the test value. This way, the different ship types can be represented by means of coefficients and valuesAnd the characteristics are further used for calculating and predicting the transverse component force of the water flow force.
Through physical model test, the coefficients are set
Sum coefficient->
Selected as in table 1 below:
table 1 coefficients
Sum coefficient->
Is of the value of (2)
Coefficient of longitudinal component of force for water flow
Divided into longitudinal shape drag coefficient of ship>
And coefficient of friction of hull->
Wherein->
Is related to the water depth to draft ratio. When (when)d/D≤1.5，/>
Taking 0.27; when (when)d/D＞1.5，/>
Take 0.17./>
Reynolds number and hull roughness correction coefficient for the effect of the water flow on the vessel>
Related to; eccentric coefficient for water flow force->
The influence degree of the change of the flow direction angle is the greatest, the influence of other factors is relatively negligible, and the water flow force eccentric coefficient is obtained by analysis according to the test result>
And the flow direction angle->
A relationship value.
Eccentric coefficient of water flow force
Selected as in table 2 below.
TABLE 2 Water flow force eccentricity coefficient
The coefficients are derived based on experimental data and theory of physical models of water flow forces acting on the ship and can be used for numerical simulation or prediction of the behavior of different types of physical models of the ship. The derivation of these coefficients is generally based on existing scientific techniques and known means. In the fields of physics, engineering, chemistry, etc., many experimental and theoretical-based methods have been developed to determine these coefficients, such as regression analysis, least squares, finite element methods, etc. By means of these methods, the experimental data can be processed and analyzed, and the required operational coefficients can be extracted therefrom. In addition, there are many mathematical and computational tools available for solving unknown parameters in model equations, such as numerical optimization, calculus, linear algebra, and the like. These tools and techniques can assist in determining these coefficients and further optimize and verify the accuracy and reliability of the physical model.
Coefficient of transverse component of water flow force
The calculation is performed according to the following formula:
in the method, in the process of the invention,
-a vessel draft (m) corresponding to the vessel loading;d-designing the water depth (m); />
、/>
-setting coefficients of the vessel based on a physical model test of the water flow forces acting on the vessel; />
-the angle of flow (°) of the water flow with respect to the longitudinal axis of the vessel;
is the base of natural logarithms.
Longitudinal component of water flow force acting on ship
，/>
The calculation is performed according to the following formula:
in the method, in the process of the invention,
-a longitudinal component (kN) produced by the shape resistance; />
-a longitudinal component (kN) produced by the frictional resistance.
Longitudinal force component due to shape resistance
The calculation is performed according to the following formula:
in the method, in the process of the invention,
-a longitudinal shape drag coefficient of the vessel; />
-Water tightness (t/m) 3 ）；/>
-water flow velocity (m/s);
-width (m); />
-a vessel draft (m) corresponding to the vessel loading; />
-the angle of flow (°) of the water flow with respect to the longitudinal axis of the vessel;
when (when)d/D≤1.5，
Taking 0.27;
when (when)d/D＞1.5，
Take 0.17.
Longitudinal component of friction resistance
The calculation is performed according to the following formula:
in the method, in the process of the invention,
-coefficient of friction of the hull; />
-water density; />
-water flow rate; />
-wet surface area below the waterline of the vessel; />
-angle of flow of water with respect to the longitudinal axis of the vessel.
Wherein the friction resistance coefficient of the ship body
The calculation is performed according to the following formula:
in the method, in the process of the invention,
-reynolds number of the water flow acting on the vessel; />
-hull roughness correction coefficient->
Taking 0.4X10 -3 。
Wherein the Reynolds number of the water flow acting on the ship
The calculation is performed according to the following formula:
in the method, in the process of the invention,
-water flow velocity (m/s); />
-the waterline length (m) of the vessel; />
-the kinematic viscosity coefficient of water (m 2/s); />
-the angle of flow (°) of the water flow with respect to the longitudinal axis of the vessel.
Wherein the kinematic viscosity coefficient of water
The values of table 3 may be used;
TABLE 3 kinematic viscosity coefficient of water
Wherein the wet surface area is below the waterline of the vessel
The calculation is performed according to the following formula:
in the method, in the process of the invention,
-the waterline length (m) of the vessel; />
-a vessel draft (m) corresponding to the vessel loading; />
-square coefficients of the vessel; />
-width (m).
Water flow force deflection moment acting on ship
，/>
The calculation is performed according to the following formula:
in the method, in the process of the invention,
-water flow force eccentricity coefficient; />
-a transverse component (kN) of the water flow force acting on the vessel; />
-the vertical line length (m) of the vessel.
By taking a certain engineering as an embodiment
Step one:
according to the project feasibility study report, the project is stopped at a 30-ten thousand-ton tanker, and the ship-shaped scale is designed as shown in Table 4. Designing high water level +5.8, low water level +2.6m, and mud elevation-22.15 m, see FIG. 1, water flow rate
1.5m/s.
Table 4 30 ten thousand ton tanker scale
Step two:
analyzing water flowDetermining the flow direction angle of water flow and the longitudinal axis of the ship from the starboard incoming flow or the starboard incoming flow of the ship
As well as the direction of the lateral force component of the water flow force, the longitudinal force component of the water flow force and the deflection moment of the water flow force, see in detail figures 2 and 3. In this embodiment, the water flows from the port side of the vessel, and the flow angle of the water flow and the longitudinal axis of the vessel is +.>
15 deg..
Calculating the design water depthdDesign water depthd=Design water level—Design mud surface heightAnd (5) processing. In the present embodiment of the present invention,taking design of low water level as an example, design of water depthd=Design of low water level-Design mud elevation=2.6- (-22.15) =24.75 m.
Step three:
calculating the transverse component of the water flow force acting on the ship, wherein the calculation formulas are shown in the formula (5) and the formula (6), and the coefficients are as follows
: sea cargo 0.38, inland cargo 0.33, square barge 0.36 for coefficient +.>
: sea cargo ship 0.05, inland cargo ship 0.10, square barge 0.30. In this embodiment, the 30 ten thousand ton tanker belongs to the offshore cargo ship, coefficient
Sum coefficient->
0.38 and 0.05 were taken separately. The draft of the ship when fully loaded>
Is 22.5m, designs the water depth of low water leveld24.75m, the angle of flow of the water flow with respect to the longitudinal axis of the vessel +.>
15 degrees, water is sea water, and water is watertight>
=1.025t/m 3 Water flow speed->
1.5m/s, the vertical line length of the ship is +.>
326m, solving the above formula in a combined way to calculate the transverse component of the water flow force +.>
。
Calculating longitudinal component force of water flow force acting on ship, the calculation formula is shown in the above formula (7) -formula (12), wherein, for the longitudinal shape of ship, the resistance coefficient
When the water depth is designeddIs in draft with the shipDThe ratio is 0.27 when it is less than or equal to 1.5, and 0.17 when it is greater than 1.5.
In this embodiment, the vessel is at full load at draft
Is 22.5m, designs the water depth of low water leveldThe thickness of the material was set to 24.75m,d/D=1.1 is less than 1.5, ship longitudinal form drag coefficient +.>
Taking 0.27, using the formula (8), the longitudinal component +.>
。
The waterline length of the ship when fully loaded
329m, width->
60m sea at 20 DEG CCoefficient of kinetic viscosity of water->
1.05X10) -6 m 2 S, the longitudinal component force generated by the frictional resistance can be calculated by using the formulas (9) - (12)>
。
Longitudinal force component to be generated by shape resistance
+longitudinal component due to frictional resistance +.>
Namely, formula (7), the total longitudinal component of the water flow force +.>
。
Calculating deflection moment generated by action of water flow on ship
The calculation formula is shown in the formula (13), wherein the water flow force eccentric coefficient is +.>
The values selected in table 2 above. In this embodiment, the flow angle of the water flow with respect to the longitudinal axis of the vessel is +.>
15 degrees, the water flow force eccentric coefficient +.>
0.182 of the transverse component of the water flow force generated by the calculated water flow acting on the ship
The deflection moment generated by the action of the water flow on the ship can be obtained by using the formula (13)>
。
In order to check the reliability of the invention, taking the 30-ten thousand ton tanker of the project as an example, the range of the flow direction angle is enlarged, namely the flow direction angle is 0 degree, 10 degree, 15 degree, 30 degree, 45 degree, 60 degree, 90 degree, 120 degree, 150 degree, 170 degree and 180 degree, and the water depth/ship draft is increasedd/DStill 1.1, water flow rate
Still 1.5m/s, water flow force under different flow direction angles is calculated, and compared with test results and standard formula calculation results of other countries, and detailed figures 4-9 are shown, and from the comparison chart of the test results, the result obtained by the calculation method provided by the invention has good consistency with the test value.
Compared with the calculation results of other national specifications, referring to fig. 7-9, the water flow force calculated by the standard specification of each country also has a certain difference:
(1) For the water flow transverse component, the formula is very consistent with the British, the United states and the OCIMF (third edition);
(2) For the water flow longitudinal component, the longitudinal component of OCIMF and British standard is basically irregular along with the change of the flow direction angle; the formula is the same as the law of the United states (UFC), the calculation result is larger than the United states (UFC), and the longitudinal component force of the water flow calculated by the formula recommended by the invention is in the calculation result of each country;
(3) For the deflection moment of water flow, only mooring equipment guidelines (third edition) and (fourth edition) published by OCIMF in the formulas of each country provide a chart of the deflection moment, and the calculation result of the formula is basically consistent with the result graph rule of the OCIMF and slightly different in size.
In summary, the calculation method recommended by the invention has good reliability, corrects and perfects the calculation method of the water flow force acting on the ship in the current port engineering load specification in China, overcomes the inconvenience of consulting different graphs when using the international standard, is basically consistent with the test result, and has little phase difference compared with the calculation result of the main international standard specification. The invention is beneficial to scientifically and efficiently solving the problem of ship load caused by water flow.
The foregoing description of the preferred embodiments of the invention is not intended to be limiting, but rather is intended to cover all modifications, equivalents, and alternatives falling within the spirit and principles of the invention.
Claims (10)
1. A comprehensive calculation method for water flow force acting on a ship is characterized by comprising the following steps: the method comprises the following steps:
determining main parameters required by calculation, including design water level, design mud elevation, water flow velocity, vertical line length, width, ship draft corresponding to ship loading degree, ship waterline length and ship square coefficient;
judging the directions of the transverse component force, the longitudinal component force and the deflection moment of the water flow force, determining the flow direction angle of the water flow and the longitudinal axis of the ship, and calculating the designed water depth;
and thirdly, calculating a transverse component of the water flow force acting on the ship, a longitudinal component of the water flow force acting on the ship and a deflection moment of the water flow force acting on the ship.
2. The method for comprehensive calculation of water flow force acting on a ship according to claim 1, wherein: the transverse component of the water flow force acting on the ship is
，/>
The calculation is performed according to the following formula:
in the method, in the process of the invention,
coefficient of transverse component of force of water flow；
3. The comprehensive calculation method of water flow force acting on a ship according to claim 2, characterized in that: coefficient of transverse component of water flow force
The calculation is performed according to the following formula:
in the method, in the process of the invention,
-a vessel draft corresponding to the vessel loading;
d -design water depthdDesign water level-design mud level elevation;
4. The method for comprehensive calculation of water flow force acting on a ship according to claim 1, wherein: longitudinal component of water flow force acting on ship
，/>
The calculation is performed according to the following formula:
in the method, in the process of the invention,
-a longitudinal component of force generated by the shape resistance;
5. The method for comprehensively calculating the water flow force acting on the ship according to claim 4, wherein: longitudinal force component due to shape resistance
The calculation is performed according to the following formula:
in the method, in the process of the invention,
-a longitudinal shape drag coefficient of the vessel;
design water depth asd=Design water level-design mud level elevation, whend/D≤1.5，
=0.27 when D/D > 1.5, +.>
=0.17。
6. The method for comprehensively calculating the water flow force acting on the ship according to claim 4, wherein: longitudinal component of friction resistance
The calculation is performed according to the following formula:
in the method, in the process of the invention,
-coefficient of friction of the hull;
7. The method for comprehensively calculating the water flow force acting on the ship according to claim 6, wherein: coefficient of friction of ship body
The calculation is performed according to the following formula:
in the method, in the process of the invention,
-reynolds number of the water flow acting on the vessel;
8. The comprehensive calculation method of water flow force acting on a ship according to claim 7, wherein: reynolds number of water flow acting on ship
The calculation is performed according to the following formula:
in the method, in the process of the invention,
-water flow rate;
9. The method for comprehensively calculating the water flow force acting on the ship according to claim 6, wherein: wet surface area below the waterline of a ship
The calculation is performed according to the following formula:
in the method, in the process of the invention,
-long waterline of the vessel;
10. A method of integrated calculation of the water flow force acting on a vessel according to claim 1, 2 or 3, characterized in that: water flow force deflection moment acting on ship
，/>
The calculation is performed according to the following formula:
in the method, in the process of the invention,
-water flow force eccentricity coefficient;
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