KR102434772B1 - System and method for providing sea margin of a vessel and computer-readable recording medium thereof - Google Patents

Abstract

The ship's seamargin derivation system according to an embodiment of the present invention simulates or test-runs the ship's sailing process, analyzes the actual operational performance of the ship, and through this, the ship's seamargin derives seamargin. A system for deriving a derivation device and a device database in which various data of the derivation device and the device for derivation of the ship are stored. The operation information extracted to analyze the operation performance of the ship, the marine environment information according to the operation route of the ship, the operation command speed of the ship, and the hull pollution effect coefficient of the ship are stored, and the shimajin of the ship is derived. The device includes the marine environment information according to the navigation route of the ship, the AIS data or the navigation information extracted from the real ship measurement device, the operation command speed of the ship, the hull pollution effect coefficient of the ship, and the dynamic characteristics of the ship The first RPM of the engine is derived by performing a simulation according to the navigation route of the ship using the maneuverable motion equation that can be simulated, and extracted from the AIS data or the real ship measuring device under the condition that the ship operates in still water. The second RPM of the engine is derived by performing a simulation according to the navigation route of the ship using the operation information, the operation command speed of the ship, and a steering motion equation capable of simulating the dynamic characteristics of the ship, and the derivation By calculating the first output of the engine from the first RPM of the obtained engine, and calculating the second output of the engine from the derived second RPM of the engine, shimajin = ((first output) - (second output) )) / (second output) is characterized in deriving the ship's shimajin.

Description

A system and method for deriving a ship's simazine, a computer program for executing the method on a computer is recorded, and a computer readable recording medium

The present invention provides a system and method for deriving a ship's margin that can simulate or test the ship's operating process to analyze the actual operating performance of the ship and derive the ship's margin through this, and a method for executing the method on a computer. It relates to a computer-readable recording medium in which a computer program is recorded.

As the economic efficiency of a ship is evaluated in terms of fuel consumption due to high oil prices, a design request for a ship with higher efficiency has been raised from ship owners.

Recently, discussions on the application of Energy Efficiency Design Index (EEDI), Energy Efficiency Operational Indicator (EEOI), and Energy Efficiency Management Plan (EEMP) have been discussed by the International Maritime Organization (International Maritime Organization). , IMO). In particular, regulations of the International Organization for Standardization have been updated to evaluate the ship's performance in consideration of the energy efficiency index from the stage of ship building and test operation.

The point is not to judge the minimum required performance of the ship specified in the contract and required specifications based on the model test results and test operation results, but based on the estimated value of the actual performance of the ship that will operate in various environmental conditions.

Such changes are related to the demands of ship owners who want to verify the performance of ships built by considering various environmental and operating conditions for the performance of ships estimated on the premise of ideal operating conditions at the design stage, and the estimation and verification of actual ship performance. It is in line with the technology development direction of each shipyard that has been conducting research.

As such, as the issue of improving operational efficiency of ships has emerged as a major agenda in the era of high oil prices, various approaches are being made to monitor ship operation data and to estimate actual ship performance.

In many cases, shipping companies that operate fleets monitor the operational status of multiple ships and then take a statistical approach from the perspective of big data. From this point of view, the need for research on techniques to physically estimate the ship's performance is being raised.

In addition, requests for estimating the sea margin of the ship as well as the estimation of such real ship operation performance are being raised from ship owners.

On the other hand, the effective horsepower of the ship or the horsepower of the engine relates to a case where a ship without attachments to the bottom or propeller moves straight forward without the influence of water depth, water surface width, and wind direction. However, a ship that is actually operating should add horsepower considering the actual sailing condition to the horsepower for this ideal situation. The amount of horsepower to be added in this way is called shimajin. Shimazin cannot be simply determined because it depends on various conditions such as route, season, type, engine type, speed, and number of days of operation after departure.

Shimazin is a value selected and presented by the ordering owner and charterer based on the ship operation data currently in operation, and a specific calculation method or estimation method is not determined.

Therefore, there is a need for a method capable of accurately predicting or estimating the ship's shimajin.

The present invention has been devised to solve the above prior technical needs, and an object of the present invention is a system and method capable of deriving a ship's marginal displacement based on physical grounds such as resistance, self-navigation, motion, and maneuvering of a ship; An object of the present invention is to provide a computer-readable recording medium in which a computer program for executing the method in a computer is recorded.

A ship's sea margin derivation system according to an aspect of the present invention is a ship's sea margin derivation for simulating or test-driving a ship's operation process to analyze the actual operational performance of the ship and deriving a sea margin through this. A system for deriving the ship's margin by a device database in which various data of a device and a device for deriving the ship's marginal displacement are stored. The operation information extracted to analyze the operation performance of the ship, the marine environment information according to the operation route of the ship, the operation command speed of the ship, and the hull pollution effect coefficient of the ship are stored, and the shimajin derivation device of the ship uses a steering motion equation capable of simulating the marine environment information according to the navigation route of the ship, the AIS data or the navigation information extracted from the real ship measurement device, the navigation command speed of the ship, and the dynamic characteristics of the ship to derive the first RPM of the engine by performing a simulation according to the navigation path of the ship, and the navigation information extracted from the AIS data or the real ship measurement device, under the condition that the ship operates in still water, and the operation of the ship The second RPM of the engine is derived by performing a simulation according to the navigation path of the ship using the command speed and the steering motion equation capable of simulating the dynamic characteristics of the ship, and the engine is derived from the first RPM of the engine. calculating the first output of , and calculating the second output of the engine from the derived second RPM of the engine, simjin = ((first output) - (second output)) / (second output) It is characterized by deriving the ship's shimajin through the

In addition, the operation information extracted from the AIS data or the real ship measurement data may be a position, a bow angle, and a draft of the ship.

In addition, the marine environment information according to the navigation route of the ship may be information about wind and waves acquired by ECMWF.

In addition, the steering motion equation, the longitudinal dynamic fluid force acting on the hull, propeller and rudder of the ship, the lateral dynamic fluid force acting on the hull and rudder of the ship, and the hull and rudder of the ship In order to calculate the dynamic fluid force in the yaw direction, each dynamic fluid force acting on the ship is configured as a mathematical model for each hull, propeller and rudder, and the mathematical model verified through the model test result or trial run result for the configured mathematical model It can be an equation.

In addition, the shimajin deriving device of the ship sets the ship's navigation command speed, the initial position of the ship, the initial bow angle, and the initial draft extracted from the AIS data or the real ship measurement data as initial conditions, and the Set the target point of the ship among the AIS data or the real ship measurement data, calculate the rudder angle for moving to the target point in the initial condition, and determine whether the current draft of the ship and the initial draft are the same, and the determination If the current draft of the ship and the initial draft are the same as a result of and the initial draft are different, the operating performance of the ship may be simulated using the coefficient information re-estimated by re-estimating the coefficients of the steering motion equation as an empirical formula, the steering motion equation, and the calculated rudder angle.

In addition, the shimajin deriving device of the ship changes the rudder angle of the rudder by the calculated rudder angle, and the first of the engine based on the longitudinal and lateral forces and the yaw moment received by the ship moving to the target point. RPM and a second RPM of the engine may be derived.

In addition, the ship's shimajin derivation apparatus may derive the first RPM by considering the hull pollution effect coefficient of the ship stored in the apparatus database as the total resistance increase.

In addition, the hull pollution effect coefficient of the ship may be calculated from the rate of the speed decrease for each re-docking period of the ship.

In addition, the sea margin derivation method of a ship according to an aspect of the present invention is a method of simulating or test-driving a ship's operation process to analyze the actual operational performance of the ship and deriving the sea margin of the ship through this. , a first step of setting a steering motion equation capable of simulating the dynamic characteristics of the ship; Extracts operation information to analyze the operation performance of the ship from AIS data or real ship measurement data collected from AIS or a real ship measurement device, obtains marine environment information according to the ship's navigation route, and obtains the ship's operation command speed A second step of inputting; a third step of deriving a first RPM of the engine by performing a simulation according to the navigation route of the ship using the extracted navigation information, the acquired marine environment information, the input navigation command speed, and the steering motion equation; a fourth step of deriving a second RPM of the engine by performing a simulation according to the navigation route of the ship using the extracted navigation information, the input navigation command speed, and the steering motion equation; a fifth step of calculating a first output of the engine from the first RPM and calculating a second output of the engine from the second RPM; And from the first output and the second output, a sixth step of deriving the margin of the ship by using the margin = ((first output) - (second output)) / (second output); characterized in that

In addition, the operation information extracted from the AIS data or the real ship measurement data may be a position, a bow angle, and a draft of the ship.

In addition, the marine environment information according to the navigation route of the ship may be information about wind and waves obtained from the ECMWF.

In addition, in the first step, the longitudinal dynamic fluid force acting on the hull, propeller and rudder of the ship, the lateral dynamic fluid force acting on the hull and rudder of the ship, and the hull and rudder of the ship In order to calculate the dynamic fluid force in the yaw direction, each dynamic fluid force acting on the ship is configured as a mathematical model for each hull, propeller and rudder, and the mathematical model verified through the model test result or trial run result for the configured mathematical model You can set up an equation.

In addition, each of the third and fourth steps of performing a simulation according to the navigation route of the ship using the steering motion equation is extracted from the ship's navigation command speed and the AIS data or the real ship measurement data. A step of setting the initial position, initial bow angle and initial draft of the vessel as initial conditions; A step B of setting a target point of the vessel among the AIS data or the real ship measurement data; C step of calculating a rudder angle for moving to the target point in the initial condition; Step D of determining whether the current draft of the ship and the initial draft are the same; and, if the current draft of the ship and the initial draft are the same as a result of the determination in step D, the steering motion equation and coefficient information; The operation performance of the ship is simulated using the calculated rudder angle, and if the current draft of the ship and the initial draft are different as a result of the determination in step D, the coefficient of the steering motion equation is re-estimated as an empirical expression and re-estimated. The navigation performance of the vessel may be simulated using the estimated coefficient information, the steering motion equation, and the calculated rudder angle.

In addition, the first RPM of the engine or the second RPM of the engine based on the longitudinal and lateral forces and the yaw moment received by the ship moving to the target point by changing the rudder angle of the rudder with the calculated rudder angle It may further include step E of deriving.

In addition, in the second step, the hull pollution effect coefficient of the ship is additionally input, and in the third step, the first RPM can be derived by considering the hull pollution effect coefficient of the ship as an increase in total resistance.

In addition, the hull pollution effect coefficient of the ship may be calculated from the rate of the speed decrease for each re-docking period of the ship.

In addition, it is possible to provide a computer-readable recording medium in which a computer program for executing the method of deriving an optimal route of a ship according to the present invention on a computer is recorded.

According to an embodiment of the present invention, it is possible to derive the ship's shimajin based on a physical basis by using traditional element technologies such as resistance, self-navigation, movement, and steering of the ship.

In addition, the ship's operating performance is analyzed using the AIS data or real ship measurement data collected from the AIS or the real ship measurement device, using the ship's operation information, marine environment information, and the steering motion equation that can simulate the ship's dynamic characteristics. can do.

In addition, by estimating each output (power) according to the presence or absence of an environmental load through the analyzed ship's operational performance, and calculating this difference as the output due to the environmental load, that is, the increase in power, the increase in power is an objective basis for estimating the shimajin. It can be secured by this, and through this, it is possible to respond to the needs of various ship owners.

In addition, by additionally considering the increase in the total resistance of the ship through the coefficient of the hull pollution effect of the ship, it is possible to derive a more objective shimajin considering the operation period of the ship.

1 is a view showing a schematic configuration of a ship's shimajin system according to the present invention.
2 is a view showing a method for deriving the shimajin of a ship according to the present invention.
3 is a view showing a navigation route of a ship according to an embodiment of the present invention.
4 is a diagram illustrating marine environment information according to a navigation route of a ship according to an embodiment of the present invention.
5 is a view comparing the results of simulation according to the navigation route of the ship and the route actually operated by the ship according to an embodiment of the present invention.
6 is a view showing the operation speed of the vessel, which is simulated according to the operation path of the vessel while taking into account the presence or absence of an environmental load, when the operation command speed of the vessel is 20 knots according to an embodiment of the present invention.
7 is a view showing the operating speed of the vessel, which is simulated according to the vessel's operating path while taking into account the presence or absence of an environmental load, when the vessel's operating command speed is 12 knots according to an embodiment of the present invention.
8 is a view showing the relationship between the operating speed of the vessel, the average RPM, and the relative ratio according to the presence or absence of an environmental load by performing a simulation according to the operation path of the vessel according to an embodiment of the present invention.
9 is a view showing the relationship between the operating speed of the corresponding vessel, the average output, and the relative ratio according to the presence or absence of an environmental load by performing a simulation according to the operation path of the vessel according to an embodiment of the present invention.
10 is a view showing the rate of speed decrease according to the operating period of a ship according to an embodiment of the present invention.
11 is a graph showing a linearized graph of the rate of speed decrease according to the operating period of a ship according to an embodiment of the present invention.
12 is a graph showing the shimajin of a ship in consideration of the environmental load and the hull pollution effect coefficient of the ship according to an embodiment of the present invention.

Since the present invention can have various changes and can have various embodiments, specific embodiments are illustrated in the drawings and described in detail.

However, this is not intended to limit the present invention to specific embodiments, and should be understood to include all modifications, equivalents and substitutes included in the spirit and scope of the present invention. In describing each figure, like reference numerals have been used for like elements.

And/or when the term appears, it includes a combination of a plurality of related description items or any of a plurality of related description items.

When an element is referred to as being “connected” or “connected” to another element, it is understood that it may be directly connected or connected to the other element, but other elements may exist in between. it should be On the other hand, when it is mentioned that a certain element is "directly connected" or "directly connected" to another element, it should be understood that there is no other element in the middle.

The terms used in the present application are only used to describe specific embodiments, and are not intended to limit the present invention. The singular expression includes the plural expression unless the context clearly dictates otherwise. In the present application, terms such as “comprise” or “have” are intended to designate that a feature, number, step, operation, component part, or a combination thereof described in the specification exists, and includes one or more other features or It should be understood that the existence or addition of numbers, steps, operations, components, parts, or combinations thereof does not preclude the possibility of addition.

Unless defined otherwise, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Terms such as those defined in commonly used dictionaries should be interpreted as having a meaning consistent with the meaning in the context of the related art, and should not be interpreted in an ideal or excessively formal meaning unless explicitly defined in the present application. does not

Hereinafter, a system and method for deriving a ship's shimajin according to an embodiment of the present invention will be described in detail with reference to FIGS. 1 to 12 .

1 is a view showing the schematic configuration of a ship's shimajin system according to the present invention, Figure 2 is a view showing a shimajin derivation method for a ship according to the present invention, Figure 3 is a view showing an embodiment of the present invention It is a view showing the navigation route of a ship, and FIG. 4 is a diagram showing marine environment information according to the navigation route of the ship according to an embodiment of the present invention, and FIG. It is a view comparing the result of performing a simulation according to the route and the operation route actually operated by the ship, and FIG. 6 is a view showing the presence or absence of an environmental load when the ship's operation command speed is 20 knots according to an embodiment of the present invention. It is a view showing the operation speed of the vessel that has been simulated according to the operation route of the vessel, and FIG. 7 is a view showing the operation speed of the vessel while considering the presence or absence of environmental load when the operation command speed of the vessel is 12 knots according to an embodiment of the present invention. It is a view showing the operating speed of the corresponding vessel that has been simulated according to the operating path, and FIG. 8 is a simulation according to the operating path of the vessel according to an embodiment of the present invention. It is a view showing the relationship of the relative ratio according to the presence or absence, and FIG. 9 is a diagram showing the relative ratio according to the operation speed, average output, and environmental load of the vessel by performing a simulation according to the operation path of the vessel according to an embodiment of the present invention. It is a view showing the relationship, and FIG. 10 is a view showing the rate of decrease in speed according to the operating period of the ship according to an embodiment of the present invention, and FIG. 11 is the speed according to the operating period of the ship according to an embodiment of the present invention. It is a graph showing a linearized ratio of degradation, and FIG. 12 is a graph showing a ship's shimajin in consideration of the environmental load and the ship's hull pollution effect coefficient according to an embodiment of the present invention.

In the derivation of the ship's shimajin according to an embodiment of the present invention, the simulation is performed along the navigation path of the ship using the steering motion equation that can simulate the dynamic characteristics of the ship, with and without an environmental load. After calculating each output (power), the difference of the average output is divided by the output when there is no environmental load, and this value is defined as the ship's marginal displacement.

As shown in FIG. 1 , the system for deriving the shimajin of a ship according to an aspect of the present invention analyzes the actual operational performance of the ship by simulating or test-driving the operation process of the ship and deriving the shimajin of the ship through this. It is composed of a device database in which various data of the simazine derivation device of the ship and the shimajin derivation device of the ship are stored.

The device database includes navigation information extracted to analyze the navigation performance of a ship among AIS data or real ship measurement data collected from AIS or a real ship measurement device, marine environment information according to the navigation route of the ship, operation command speed of the ship, and a hull fouling effect coefficient of the vessel is stored.

AIS is an automatic vessel identification device that collects AIS data of all vessels in operation. The AIS data of the vessel collected in this way contains information such as the current position, speed, and draft for each time of the vessel.

Such AIS is a device that is obligatory to be mounted on ships of a certain size or larger, and it is a device that transmits the operation information of its own ship and shares the operation information by receiving the operation information of other ships. This AIS is used to acquire AIS data of other ships and is used to increase operational stability, and it is possible to receive AIS data of ships currently moving on land as well. It is possible to obtain information.

The real ship operation information acquired from shipyards and shipping companies includes all information available from AIS, and similar information can be acquired through a separate real ship measurement device.

Operation information may be extracted to analyze the operation performance of the ship from the AIS data or the actual ship measurement data collected from the AIS or the real ship measurement device.

The operation information extracted from AIS data includes static data, dynamic data, Voyage related data, safety related message, etc. In static data, 1) IMO number, in dynamic data, 1) Ship's position with accuracy indication and integrity status, 2) Time in UTC, 3) Speed over ground, Voyage related data, 1) Ship's draft, etc. can be used. In addition, the same information can be collected through a separate solid line measuring device. Preferably, the operation information for analyzing the operation performance of the ship among the AIS data or the real ship measurement data collected from the AIS or the real ship measurement device may be the position, the bow angle, and the draft of the ship.

On the other hand, the marine environment information according to the navigation route of the ship may be information about the wind and waves on the navigation route. Information on these winds and waves is available from the European Center for Medium-Range Weather Forecasts (ECMWF), the National Oceanic and Atmospheric Administration (NOAA), and the National Data Buoy Center (NDBC). ), etc., may be obtained through various sources, and preferably may be obtained from ECMWF.

The ship's operation command speed refers to the speed that is the standard of the ship in performing simulations according to the ship's navigation route using the steering motion equation to be described later. The operation command speed of such a ship may be selected in consideration of various factors such as the type, size, and type of the ship, and may be set in the range of 5 to 30 knots, which is the speed at which the ship normally operates. However, it is not limited to these figures, and it is of course possible to set a range of 40 knots or more in the case of a high-speed boat.

In addition, the hull pollution effect coefficient of the ship may be stored in the device database.

Various kinds of marine life such as shells and barnacles are attached to the part below the waterline where the hull is submerged in seawater. act as a degrading factor. For this reason, not only when a vessel under construction is anchored on the quay wall, but also in the case of a vessel in operation, after a certain period of operation, re-docking to remove marine organisms attached to the hull is performed regularly or irregularly. The redocking period is usually decided between 1 to 5 years.

In the present invention, the hull pollution effect coefficient can be calculated from the rate of speed decrease for each re-docking period of the ship.

Specifically, as shown in FIGS. 10 and 11 , the hull pollution effect coefficient can be set as a representative value obtained by linearizing the speed reduction ratio according to the operation period of the ship. In the case of FIG. 10, it can be seen that the operation of removing the marine life attached to the hull through the first re-docking was performed as the operation period reached the third year, and thereafter, it can be seen that there are two more re-docking. It can be seen that the speed of the ship steadily decreases before re-docking, and the speed of the ship increases again by removing the marine life attached to the hull through re-docking.

The hull pollution effect coefficient according to the present invention is used as a factor that considers the increase in total resistance in calculating the output when there is an environmental load. Since these hull pollution effect coefficients can be obtained based on real ship operation data or can be obtained by known algorithms and methods, there is no particular limitation on the method of obtaining or deriving them. do.

Hereinafter, the operation of the ship's margin derivation device in the ship's margin derivation system according to the present invention will be described.

The ship's shimajin derivation device uses the above-described marine environment information according to the ship's navigation route, navigation information extracted from AIS data or real ship measurement data, and a steering motion equation that can simulate the ship's operation command speed and the dynamic characteristics of the ship. It is possible to derive the RPM of the engine by performing a simulation according to the navigation route of the ship.

Since the steering motion equation has a model test result or a trial run result for the target ship, the mathematical model is verified using the model test result or the test run result of the ship to form a steering motion equation capable of simulating the dynamic characteristics of the target ship.

The steering motion equation according to the present invention can be expressed by Equation 1 below.

,

은 선박의 속도 시간 변화율을 의미한다. r은 선박의

위치의 선체 중앙부를 기준으로 회전하는 각속도를,

은 각속도의 시간변화율을 가리킨다. X, Y, N은 각각 선체에 작용하는 종방향, 횡방향의 힘과 요모멘트를 의미한다.Here, m is the mass of the ship and Izz is the mass moment of inertia of the ship. u and v denote the longitudinal and transverse velocity of the vessel, respectively,

,

is the rate of change of the ship's speed with time. r is the ship's

The angular velocity of rotation with respect to the center of the hull at the position,

is the time rate of change of the angular velocity. X, Y, and N mean the longitudinal and transverse forces and yaw moments acting on the hull, respectively.

The forces and moments acting on the hull can be divided by Equation (2). The subscript H stands for hull, P stands for propeller, R stands for rudder, WI stands for wind, and WA stands for wave.

Here, X, Y, and N may be calculated by Equations 3 to 12, respectively.

where m _x , n _y are the added masses in the longitudinal and transverse directions, L _pp is the length between water lines of the ship, T is the draft of the ship, U is the actual speed at which the ship is moving, and ρ is the density of seawater. and β is the drift angle. At this time, if the draft of the ship is different from the draft of the previous stage (the initial draft or the draft before moving to the target point), the design draft set for each speed of the ship and the resistance coefficient of the ballast are linearly interpolated, and the re-estimated resistance coefficient value is reflected. do.

Here, ur is the product of the longitudinal speed and the transverse speed of the target vessel.

where x _G is the distance from the position of the longitudinal center of gravity (LCG) to the center of the vessel.

where t is the thrust reduction coefficient, ρ is the density of seawater, n is the RPM/60 of the propeller, D _p is the diameter of the propeller, and K _T is the thrust coefficient. t and K _T are obtained through model testing.

및

은 러더각이다.where t _R is the coefficient of interference between the hull and the rudder, F _N is the direct pressure acting on the rudder (port, stbd means the direction),

and

is the rudder angle.

Here, α _H is the interference coefficient between the hull and the rudder, F _{N_PORT} is calculated using the density of seawater, the area of the rudder (PORT), the slope of the rudder (PORT) lift coefficient according to the angle of incidence, and the flow angle of incidence, F _{N_STBD} is also It is calculated using the gradient of the rudder (STBD) lift coefficient according to the density of seawater, the area of the rudder (STBD), the angle of incidence, and the angle of incidence.

X _H is the coefficient of interference between the hull and the rudder.

In addition, in order to obtain the wind load in the steering motion equation of the ship, it must be arranged in terms of the relative speed and the relative angle of incidence, and can be calculated using Equation 10 below.

는 바람의 종 방향 상대 속도이고,

는 바람의 횡 방향 상대 속도를 가리킨다.

는 종 방향 상대 속도의 제곱과 횡 방향 상대 속도의 제곱을 더한 값을 제곱근으로 계산한 값이며,

는 선체에 입사되는 상대 입사각을 가리킨다.here,

is the longitudinal relative speed of the wind,

denotes the relative speed in the transverse direction of the wind.

is the square root of the sum of the square of the longitudinal relative speed and the square of the transverse relative speed,

is the relative angle of incidence incident on the hull.

The wind load acting on the hull is calculated using Equation 11 below.

Here, C _X , C _Y , and C _N refer to the dimensionless wind load coefficients. _AT is the longitudinal projected area above the waterline of the ship, and A _L is the transverse projected area. ρ _air refers to the density of air, and L _OA refers to the total length of the vessel.

The wave load can be calculated using Equation 12. Only the average wave drift force is considered as the wave load in the steering motion equation.

는 파의 진폭을 가리킨다. E(ω)는 ITTC(International Towing Tank Committee)파 스펙트럼을 의미한다. 선박의 이동속도, 평균 파도 주기, 파도의 방향에 따라 선형 보간을 한 뒤 파랑 하중을 조종운동방정식에 외력으로 고려한다.where QTF is the average wave drift force, ω is the frequency, α is the wave incidence angle,

indicates the amplitude of the wave. E(ω) denotes an International Towing Tank Committee (ITTC) wave spectrum. After linear interpolation is performed according to the ship's moving speed, average wave period, and wave direction, the wave load is considered as an external force in the steering motion equation.

Meanwhile, in the case of Equation 2, the force and moment acting on the hull are calculated in consideration of the hull, the propeller, the rudder, the wind, and the waves. This is the formula to calculate the force and moment acting on the hull considering the environmental load.

If the factors related to wind and waves are subtracted from here, the force and moment acting on the hull are calculated without considering the environmental load, that is, under the still water operating conditions.

Calculating the longitudinal dynamic fluid force acting on the hull, propeller and rudder, the lateral dynamic fluid force acting on the hull and rudder, and the yaw dynamic fluid force acting on the hull and rudder is defined by Equations 3 to 9 Here, the load by the wind can be obtained from Equations 10 and 11, and the load due to the wave can be obtained through Equations 12 and 13.

In other words, when the environmental load is taken into account by acquiring marine environmental information according to the navigation route of the ship, the forces and moments acting on the hull can be obtained through Equations 3 to 12, The forces and moments acting on the hull, propeller and rudder can be obtained through Equations 3 to 9, ignoring the load caused by wind and waves.

The apparatus for deriving shimajin for a ship according to an embodiment of the present invention performs a simulation according to the navigation route of the ship using the steering motion equation under the condition that there is an environmental load, and as a result, the engine's first RPM to derive And, when there is no environmental load, that is, a simulation is performed according to the navigation route of the ship using the steering motion equation using the steering motion equation as a prerequisite for operation in still water, and as a result, the second RPM of the engine is derived.

In other words, when there is an environmental load as a prerequisite, the derived RPM is named as a first RPM, and when operating in still water is a prerequisite, the derived RPM is named as a second RPM.

The method of simulating the operating performance of a ship through the above-described steering motion equation is the same, except whether the environmental load is considered or not, only whether the force and moment acting on the hull are calculated in consideration of wind and waves.

Hereinafter, a process for simulating the ship's operating performance by the apparatus for deriving a ship's shimajin according to an embodiment of the present invention will be described in detail.

The apparatus for deriving a ship's shimajin according to an embodiment of the present invention receives a specific section of the ship for estimating the navigation performance from AIS data or real ship measurement data, and the initial position of the ship, the initial bow angle, the initial draft, and the operation command speed Set as the initial condition, set the target point during the movement path of the ship among AIS data or solid ship measurement data, calculate the rudder angle for moving from the initial condition to the target point, and the above-mentioned steering motion equation and coefficient information. It simulates the ship's operating performance by calculating the longitudinal and lateral forces and the yaw moment received by the ship moving to the target point by using it.

At this time, it is determined whether the draft of the target ship for moving to the target point and the initial draft are the same in the initial condition. Operational performance is simulated, and if the current draft of the target ship and the initial draft or the draft at the previous target point are different, the coefficient of the steering motion equation is re-estimated as an empirical formula, and the operation of the target ship using the re-estimated coefficient information and the steering motion equation Simulate performance. If the initial draft of the ship or the draft at the previous target point is different, the resistance coefficients of the design draft and the ballast draft set for each speed of the ship are linearly interpolated, and the steering motion equation is solved by reflecting the estimated resistance coefficient value.

More specifically, the ship's shimajin derivation device calculates the longitudinal and lateral forces and yaw moment received by the target ship moving to the above-described target point through the above-mentioned equations, and calculates the longitudinal and lateral directions and The actual operating performance of the target ship can be estimated based on the results including the engine RPM and rudder angle obtained using the lateral force and yaw moment.

On the other hand, the ship's shimajin derivation apparatus derives the RPM of the engine in the case where the environmental load is considered by the above-described simulation process and the environmental load is not, that is, in the still water operating conditions, respectively, and when the environmental load is considered, the first RPM As a result, in the case of the operation condition in still water, it is derived as the 2nd RPM.

The apparatus for deriving the shimajin of the ship may calculate the first output and the second output of the engine from the derived first and second RPMs of the engine, respectively.

In general, it is expressed as the power V required for the vessel to sail at the speed V[m/s] while receiving the resistance [R _T ]. Here, R _T ∝ V ² (total resistance is proportional to almost the square of the speed), so the above equation can be changed to P ∝ V ³ . That is, the power required for the navigation of the ship, that is, the output is proportional to the third power of the speed.

By using the first output and the second output calculated in this way, the ship's Shim-jin and Shim-jin derivation apparatus can obtain the ship's Shim-jin through the following equation.

Shimazine = ((1st output) - (2nd output)) / (2nd output)

On the other hand, the ship's shimajin derivation system according to an embodiment of the present invention may additionally consider the hull pollution effect coefficient of the ship as an increase in total resistance in deriving the first RPM in consideration of the environmental load.

Specifically, the increase in resistance due to hull pollution may be included in the term X _H expressed by Equation 3 above. As mentioned above, X _H is proportional to the square of U , that is, the actual speed of the ship, that is, U ² , and X _UU is a coefficient obtained through model tests, etc. At this time, the hull pollution effect coefficient may be reflected in the X _UU . For example, if the hull pollution effect coefficient is 1%/month, the increase in resistance can be considered in the form of X _UU *(1+0.01).

Hereinafter, a method of deriving an optimal route for a ship according to the present invention will be described with reference to FIGS. 3 to 12 .

First, a steering motion equation that can simulate the dynamic characteristics of a ship is established (Step 1). The steering motion equation is an equation for calculating the longitudinal force, lateral force, and yaw moment received by the ship, and can be set with reference to Equations 1 to 12 described above.

Next, in order to analyze the operation performance of the vessel from the AIS data or the actual vessel measurement data collected from the AIS or the real ship measurement device, the operation information is extracted, the marine environment information is obtained according to the operation route of the ship, and the operation command speed of the ship Enter (2nd step).

Here, the operation information from which the AIS data is extracted includes static data, dynamic data, Voyage related data, safety related message, etc., among static data, 1) IMO number, and among dynamic data, 1) Ship's position with accuracy indication and integrity Status, 2) Time in UTC, 3) Speed over ground, Voyage related data, 1) Ship's draft, etc. can be used. In addition, the same information can be collected through a separate solid line measuring device. Preferably, the operation information for analyzing the operation performance of the ship among the AIS data or the real ship measurement data collected from the AIS or the real ship measurement device may be the position, the bow angle, and the draft of the ship.

More specifically, it is possible to selectively acquire flight information for a specific period from among AIS data or solid line measurement data. The sailing route of the ship that departed and operated to Japan as of June 17, 2016 over about 26 days was selected, and the movement route taken from the AIS data of the ship is well illustrated in FIG. 3 .

In addition, the marine environment information according to the navigation route of the ship may be acquired through sources such as ECMWF, NOAA, NDBC, etc. as information about wind and waves on the navigation route, preferably from the ECMWF.

FIG. 4 shows information about wind and waves obtained from the ECMWF in the navigation route of the ship shown in FIG. 3 .

In addition, the ship's operation command speed is the speed of the ship as a reference in performing the simulation through the steering motion equation, and any value within the speed range at which the ship can operate can be set and input. In one embodiment of the present invention, the ship's operation command speed was set to a value between 12 knots and 20 knots.

Next, a simulation is performed according to the navigation path of the vessel using the extracted navigation information, the acquired marine environment information, the input navigation command speed, and the steering motion equation set in the first step, so that the first engine Derive the RPM (3rd step).

Specifically, the section of the vessel is set (starting point and arrival point), and initial conditions are set using the initial position, initial bow angle and initial draft, which are information of the departure point among the set sections, and the input operation command speed. And the target point of the ship is set along the movement path of the set section, and the target point is determined as the point where the rudder angle needs to be changed, and the final target point is determined after passing through a plurality of transit target points during the movement of the ship. Calculates the rudder angle of the ship to move from the initial position to the next set target point, and determines whether the draft information of the ship included in the AIS data or the real ship measurement data of the ship moving to this target point is the same as the initial draft. . As a result of this determination, if the draft of the ship included in the AIS data of the ship moving to the target point is the same as the initial draft, the maneuvering performance of the ship is simulated using the steering motion equation and coefficient information (fluid force differential coefficient) set in the first step. . After the simulation is performed, it is determined whether or not the target point is reached, and if the determination result does not reach the target point, the simulation is repeated, and when the final target point is reached, the simulation is terminated. On the other hand, when the draft information of the ship included in the ship's AIS data or the real ship measurement data is different from the initial draft, the coefficient of the steering motion equation (fluid force differential coefficient) is re-estimated in an empirical way. The coefficient is a resistance coefficient, and based on the design draft and ballast draft set for each speed of the ship, the design draft and ballast draft set for the speed of the target ship are estimated using a linear interpolation method. Using this re-estimated coefficient information and the steering motion equation, the ship's operating performance is simulated. Through the above-mentioned steering motion equation, the longitudinal force, lateral force, and yaw moment that the vessel receives when the vessel moves to the target point are calculated, and the calculated longitudinal force, lateral force and yaw direction received by the vessel are calculated. The first RPM of the engine is derived through the moment.

Next, the second RPM of the engine is derived by performing a simulation according to the navigation route of the ship using the extracted navigation information, the input navigation command speed, and the steering motion equation set in the first step (fourth). step).

The second RPM of the engine is a condition of operation in the still water, and there is only a difference between the first RPM and whether environmental loads are considered, and the specific process of deriving the second RPM is the first RPM of the third step. It is the same as the extraction process.

As shown in FIGS. 5 to 7, when comparing the position and speed of the vessel calculated based on the AIS route, if the route point is well followed and there is a diagonal change in the entire route and in the section with the diagonal change It was found that some loss of ship speed is occurring according to the characteristics, but considering that this is a phenomenon that can only occur during actual operation, it can be confirmed that the ship follows the operation command speed well.

Next, a first output and a second output of the engine are calculated from the derived first RPM and second RPM of the engine, respectively (fifth step). As mentioned above, the output of the engine can be calculated by utilizing the point that the power required for the navigation of the ship, that is, the output is proportional to the third power of the speed.

As shown in FIGS. 8 and 9 , it can be confirmed that the average RPM has a linear relationship to the speed, and the average output has a cubic relationship.

Finally, from the calculated first and second outputs of the engine, the ship's margin is derived using the following equation (seventh step).

Shimazine = ((1st output) - (2nd output)) / (2nd output)

8 and 9 show graphs in which the relative ratio of the average RPM and the average output according to the presence or absence of an environmental load is calculated.

On the other hand, in the method of deriving the shimajin of a ship according to an embodiment of the present invention, the accuracy of shimajin can be increased by additionally considering a portion in which resistance increases as marine organisms such as barnacles or shells are attached to the hull. have.

In the second step, the hull pollution effect coefficient of the ship is additionally input, and in the third step, the first RPM can be derived by considering the hull pollution effect coefficient of the ship as an increase in total resistance.

Here, as described above, the ship's hull pollution effect coefficient may be a value calculated from the rate of speed decrease for each re-docking period of the ship.

Specifically, the increase in resistance due to hull pollution may be included in the term X _H expressed by Equation 3 above. As mentioned above, X _H is proportional to the square of U , that is, the actual speed of the ship, that is, U ² , and X _UU is a coefficient obtained through model tests, etc. At this time, the hull pollution effect coefficient may be reflected in the X _UU . For example, if the hull pollution effect coefficient is 1%/month, the increase in resistance can be considered in the form of X _UU *(1+0.01).

10 and 11, the rate of the speed decrease according to the operating period of the vessel and a graph obtained by linearizing it are shown.

On the other hand, FIG. 12 is a graph showing the shimajin in consideration of the environmental load and the ship's hull pollution effect coefficient (0.4518%/month) based on the design draft of the ship and the ship's operation command speed (20 knots) according to an embodiment of the present invention. , and it can be seen that the shimajin of approximately 7 to 28% is estimated depending on the redocking period.

In the above, the present invention has been described with reference to the embodiments shown in the drawings. However, the present invention is not limited thereto, and various modifications or other embodiments within the scope equivalent to the present invention are possible by those of ordinary skill in the art to which the present invention pertains. Accordingly, the true protection scope of the present invention should be defined by the following claims.

100: ship's shimajin derivation device 200: device database

Claims (17)

Various data of the ship's sea margin derivation apparatus and the ship's sea margin derivation device for analyzing the actual operational performance of the ship by simulating or trial running the ship's operation process and deriving sea margin through this are stored. A system for deriving the ship's shimajin by means of a device database, comprising:
The device database includes navigation information extracted to analyze the navigation performance of the ship from AIS data or real ship measurement data collected from AIS or a real ship measurement device, maritime environment information according to the ship's route, and the ship's operation command speed. , the ship's hull pollution effect coefficient is stored,
The ship's shimajin derivation device,
The marine environment information according to the navigation route of the ship, the navigation information extracted from the AIS data or the real ship measurement device, the operation command speed of the ship, the hull pollution effect coefficient of the ship, and the dynamic characteristics of the ship can be simulated. The first RPM of the engine is derived by performing a simulation according to the navigation path of the ship using the steering motion equation in the
Under the condition that the vessel operates in still water, the vessel using the operation information extracted from the AIS data or the solid line measuring device, the vessel’s operating command speed, and a steering motion equation capable of simulating the dynamic characteristics of the vessel The second RPM of the engine is derived by performing a simulation according to the
calculating the first output of the engine from the derived first RPM of the engine, and calculating the second output of the engine from the derived second RPM of the engine,
formula
Shimazine = ((1st output) - (2nd output)) / (2nd output)
A system for deriving the shimajin of the ship, characterized in that through The method of claim 1,
The ship's shimajin deriving system, characterized in that the operation information extracted from the AIS data or the real ship measurement data is a position, a bow angle, and a draft of the ship. The method of claim 1,
The marine environment information according to the sailing route of the ship is information about wind and waves obtained by ECMWF. The method of claim 1,
The steering motion equation is the longitudinal dynamic fluid force acting on the hull, propeller and rudder of the ship, the lateral dynamic fluid force acting on the hull and rudder of the ship, and the yaw direction acting on the hull and rudder of the ship In order to calculate the dynamic fluid force of Ship's shimajin derivation system, characterized in that. 5. The method of claim 4,
The ship's shimajin derivation device,
Setting the operation command speed of the ship, the initial position of the ship extracted from the AIS data or the real ship measurement data, the initial bow angle, and the initial draft as initial conditions,
Set the target point of the ship among the AIS data or the real ship measurement data,
calculating a rudder angle for moving to the target point in the initial condition,
It is determined whether the current draft of the ship and the initial draft are the same,
If the current draft of the ship and the initial draft are the same as the result of the determination, the operation performance of the ship is simulated using the steering motion equation and coefficient information and the calculated rudder angle,
If the current draft of the ship and the initial draft are different as a result of the determination, the coefficient information of the steering motion equation is re-estimated as an empirical equation, the re-estimated coefficient information, the steering motion equation, and the calculated rudder angle. A ship's shimajin derivation system, characterized in that it simulates the ship's operating performance. 6. The method of claim 5,
The ship's shimajin derivation device,
Shimazine derivation system of a ship, characterized in that by changing the rudder angle of the rudder with the calculated rudder angle, and deriving the RPM of the engine based on the longitudinal and lateral forces and the yaw moment received by the ship moving to the target point . 7. The method of claim 6,
The ship's shimajin derivation device,
Shimazine derivation system of a ship, characterized in that the first RPM is derived by considering the hull pollution effect coefficient of the ship as an increase in total resistance 8. The method of claim 7,
The ship's hull pollution effect coefficient is a ship's shimajin derivation system, characterized in that it is calculated from the rate of speed decrease for each re-docking period of the ship. A method of analyzing the actual operation performance of the vessel by simulating or test-driving the operation process of the vessel and deriving the sea margin of the vessel through this,
a first step of setting a steering motion equation capable of simulating the dynamic characteristics of the ship;
In order to analyze the operation performance of the ship from AIS data or real ship measurement data collected from AIS or a real ship measurement device, operation information is extracted, and marine environment information according to the operation route of the ship is obtained, and the hull pollution effect of the ship a second step of inputting a coefficient and inputting a navigation command speed of the vessel;
Using the extracted navigation information, the acquired marine environment information, the inputted hull pollution effect coefficient, the inputted navigation command speed, and the steering motion equation, a simulation is performed according to the navigation route of the ship to determine the first engine of the engine. a third step of deriving RPM;
a fourth step of deriving a second RPM of the engine by performing a simulation according to the navigation route of the ship using the extracted navigation information, the input navigation command speed, and the steering motion equation;
a fifth step of calculating a first output of the engine from the first RPM and calculating a second output of the engine from the second RPM; and
From the first output and the second output,
Shimazine = ((1st output) - (2nd output)) / (2nd output)
a sixth step of deriving the ship's shimajin using
A method of deriving the shimajin of a ship, characterized in that it comprises a. 10. The method of claim 9,
The sailing information extracted from the AIS data or the real ship measurement data is a ship's shimajin derivation method, characterized in that the ship's position, bow angle, and draft are. 10. The method of claim 9,
The marine environment information according to the navigation route of the ship is information about wind and waves obtained from the ECMWF. 10. The method of claim 9,
The first step is
Calculating the longitudinal dynamic fluid force acting on the hull, propeller and rudder of the vessel, the transverse dynamic fluid force acting on the hull and rudder of the vessel, and the yaw dynamic fluid force acting on the hull and rudder of the vessel For each dynamic fluid force acting on the ship, a mathematical model is configured for each hull, propeller, and rudder, and an equation verified through a model test result or a trial run result for the constructed mathematical model is set, characterized in that A method of deriving a ship's shimajin. 13. The method of claim 12,
The third and fourth steps of performing a simulation according to the navigation route of the ship using the steering motion equation are,
A step of setting the operation command speed of the ship, the initial position of the ship extracted from the AIS data or the real ship measurement data, an initial bow angle, and an initial draft as initial conditions;
A step B of setting a target point of the vessel among the AIS data or the real ship measurement data;
C step of calculating a rudder angle for moving to the target point in the initial condition;
D step of determining whether the current draft of the ship and the initial draft are the same;
including,
If the current draft of the ship and the initial draft are the same as the result of the determination in step D, the operation performance of the ship is simulated using the steering motion equation and coefficient information, and the calculated rudder angle,
If the current draft of the ship and the initial draft are different as a result of the determination in step D, the coefficient information of the steering motion equation is re-estimated as an empirical equation, the re-estimated coefficient information, the steering motion equation, and the calculated rudder angle A method of deriving the shimajin of a ship, characterized in that it simulates the operation performance of the ship by using it. 14. The method of claim 13,
By changing the rudder angle of the rudder with the calculated rudder angle, the step E of deriving the RPM of the engine based on the longitudinal and lateral forces received by the ship moving to the target point, and the yaw moment, characterized by further comprising a step E A method of deriving a ship's shimajin. 15. The method of claim 14,
The third step is
A method for deriving the first RPM by considering the hull pollution effect coefficient of the ship as an increase in total resistance. 16. The method of claim 15,
The ship's hull pollution effect coefficient is a method of deriving the shimajin of a ship, characterized in that calculated from the rate of speed decrease for each re-docking period of the ship. A computer program for executing the method of deriving a ship's simazine according to any one of claims 9 to 16 on a computer is recorded, a computer readable recording medium.

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