WO2024069777A1

WO2024069777A1 - Analytical device and program

Info

Publication number: WO2024069777A1
Application number: PCT/JP2022/036056
Authority: WO
Inventors: 徹郎柳田
Original assignee: 日本郵船株式会社
Priority date: 2022-09-28
Filing date: 2022-09-28
Publication date: 2024-04-04

Abstract

An analytical device (40) comprises: a first determining means (412) for determining an amount of increase in a first torque coefficient of a propeller caused by a change in an entire surface state including a hull of a ship and the propeller; a first acquiring means (411) for acquiring a value indicating the surface state of the propeller; a second determining means (413) for determining, using this value, an amount of increase in a second torque coefficient of the propeller caused by a change in the surface state of the propeller; a third determining means (414) for determining, using the amount of increase in the first torque coefficient and the amount of increase in the second torque coefficient, an amount of increase in a third torque coefficient of the propeller caused by a change in the surface state of the hull; and an output means (46) for outputting the amount of increase in the second torque coefficient, and the amount of increase in the third torque coefficient.

Description

Analytical device and program

The present invention relates to a technology for analyzing the causes of deterioration in ship performance.

Technology for evaluating hull fouling is known (for example, Patent Document 1).

JP 2018-27740 A

Factors that can cause a ship's performance to decline include those caused by the surface condition of the propeller and those caused by the surface condition of the hull. Depending on the cause of the ship's performance decline, the maintenance method may differ. However, with conventional technology, it was not possible to distinguish and evaluate whether the cause of the ship's performance decline was caused by the surface condition of the propeller or the surface condition of the hull.

The purpose of this invention is to make it possible to distinguish and evaluate whether the cause of a decline in ship performance is due to the surface condition of the propeller or the surface condition of the hull.

One aspect of the present invention provides an analysis device that includes a first determination means for determining an increase in a first torque coefficient of the propeller caused by a change in the overall surface condition including the ship's hull and propeller, a first acquisition means for acquiring a value indicating the surface condition of the propeller, a second determination means for determining an increase in a second torque coefficient of the propeller caused by a change in the surface condition of the propeller using the value, a third determination means for determining an increase in a third torque coefficient of the propeller caused by a change in the surface condition of the hull using the increase in the first torque coefficient and the increase in the second torque coefficient, and an output means for outputting the increase in the second torque coefficient and the increase in the third torque coefficient.

The third determination means may determine the difference between the increase in the first torque coefficient and the increase in the second torque coefficient as the increase in the third torque coefficient.

The first determination means may determine the increase in the first torque coefficient using the torque and rotation speed of the propeller measured while the ship is sailing.

The analysis device may further include a storage means for storing correspondence information indicating a correspondence between the increase in the second torque coefficient of at least one propeller obtained from the past performance of at least one ship and the effect obtained by maintenance of the at least one propeller, and a generation means for generating effect information indicating the effect obtained by maintenance of the propeller according to the increase in the second torque coefficient based on the correspondence information, and the output means may output the generated effect information.

The analysis device may further include a storage means for storing correspondence information indicating a correspondence between the increase in the third torque coefficient of at least one propeller obtained from the past performance of at least one ship and the effect obtained by maintenance of the hull of the at least one ship, and a generation means for generating effect information indicating the effect obtained by maintenance of the hull according to the increase in the third torque coefficient based on the correspondence information, and the output means may output the generated effect information.

The analysis device further includes a storage means for storing first correlation information indicating a correlation between past first voyage conditions of at least one ship and an increase in the second torque coefficient of at least one propeller actually caused by navigation in accordance with the first voyage conditions of the at least one ship, and second correlation information indicating a correlation between the first voyage conditions and an increase in the third torque coefficient of the at least one propeller actually caused by navigation in accordance with the first voyage conditions of the at least one ship, a second acquisition means for acquiring second voyage conditions planned for the ship, and an estimation means for estimating, based on the first correlation information and the second correlation information, the increase in the second torque coefficient and the increase in the third torque coefficient of the propeller when the ship navigates in accordance with the second voyage conditions, respectively, and the output means may further output the estimated increase in the second torque coefficient and the estimated increase in the third torque coefficient.

Another aspect of the present invention provides a program for causing a computer to execute the steps of: determining an increase in a first torque coefficient of the propeller caused by a change in the overall surface condition including the ship's hull and the propeller; acquiring a value indicating the surface condition of the propeller; using the value to determine an increase in a second torque coefficient of the propeller caused by a change in the surface condition of the propeller; using the increase in the first torque coefficient and the increase in the second torque coefficient to determine an increase in a third torque coefficient of the propeller caused by a change in the surface condition of the hull; and outputting the increase in the second torque coefficient and the increase in the third torque coefficient.

The present invention makes it possible to distinguish and evaluate whether the cause of a decline in ship performance is due to the surface condition of the propeller or the surface condition of the hull.

FIG. 1 illustrates an example of an analysis system according to an embodiment. FIG. 2 illustrates an example of a configuration of a server device. FIG. 2 is a diagram showing an example of the relationship between the surface roughness of a propeller and the performance of the propeller. FIG. 4 is a diagram showing an example of a first table and a second table. 13 is a flowchart showing an example of the operation of a server device for analyzing a deterioration in ship performance. 11 is a sequence chart showing an example of an operation for analyzing a correlation between navigation conditions and an increase amount of a torque coefficient. 10 is a flowchart showing an example of an operation for estimating a deterioration in performance of a vessel.

Configuration Fig. 1 is a diagram showing an example of an analysis system 1 according to an embodiment. The analysis system 1 analyzes whether the cause of the performance degradation of the ship 11 is due to the surface condition of the propeller 110 or the surface condition of the hull. The "hull" here refers to the outer hull structure of the ship 11 and does not include the propeller 110. The surface condition includes surface roughness and fouling. This fouling refers to the attachment of biological deposits called biofilms, barnacles, and the like.

In this embodiment, the increase in the torque coefficient is used as an index value indicating the deterioration of the performance of the ship 11. The performance of the ship 11 is shown by a performance curve showing the relationship between the rotation speed, horsepower, and fuel consumption. According to this performance curve, assuming the same rotation speed, when the torque coefficient of the propeller 110 increases, the torque increases according to the relationship Q = Kq x ρn^2 x D^5, and therefore the horsepower and fuel consumption, which are the product of the torque and the rotation speed, also increase. Here, Q is the torque of the main shaft, Kq is the total torque coefficient, ρ is the density of seawater, n is the rotation speed of the main engine, and D is the propeller diameter. Furthermore, in practice, it is required to keep the thrust constant in order to maintain the ship speed, but when the torque coefficient increases due to the deterioration of the propeller surface condition, the thrust coefficient also decreases, so it is necessary to increase the rotation speed according to the relationship T = Kt x ρn^2 x D^4. Here, T is the thrust, Kt is the thrust coefficient, ρ is the density of seawater, n is the rotation speed of the main engine, and D is the propeller diameter. This effect also increases torque, horsepower, and fuel efficiency. In this way, when the torque coefficient of the propeller 110 increases, the performance of the vessel 11 decreases. Therefore, the increase in the torque coefficient is an index value that indicates the decrease in performance of the vessel 11.

The analysis system 1 includes a terminal device 10 and a server device 40. The terminal device 10 is mounted on a ship 11. The terminal device 10 and the server device 40 are connected to a network 52. The network 52 includes, for example, a communication satellite 50 and the Internet. Note that although only a single ship 11 is shown in FIG. 1, multiple ships 11 may be included.

The ship 11 has a propeller 110 and is propelled by the rotation of the propeller 110. In addition to the terminal device 10 described above, the ship 11 is provided with various sensors (not shown). The various sensors include a tachometer, a torque sensor, a speedometer, a positioning sensor, and a thermometer (all not shown). The tachometer measures the rotation speed of the main engine of the ship 11, i.e., the rotation speed of the propeller 110. The torque sensor measures the torque of the main shaft of the propeller 110. The speedometer measures the speed of the ship 11. The positioning sensor measures the position of the ship 11 at a predetermined time interval. The positioning sensor is, for example, a GNSS (Global Navigation Satellite System) receiver. The route of the ship 11 is obtained by connecting the positions of the ship 11 measured by the positioning sensor in a chronological order. The thermometer measures seawater temperature. The terminal device 10 acquires the output of various sensors and transmits the acquired output or information obtained from this output to the server device 40 via the network 52.

FIG. 2 is a diagram showing an example of the configuration of the server device 40. The server device 40 is installed on land. The server device 40 separately determines and outputs the increase in the total torque coefficient including the propeller 110 and the hull, the increase in the torque coefficient of the propeller 110, and the increase in the torque coefficient of the hull. The server device 40 is an example of an "analysis device" according to the present invention. The server device 40 comprises a processor 41, a memory 42, a storage 43, a communication IF (Interface) 44, an input unit 45, and a display unit 46. Each unit of the server device 40 is connected via a bus.

The processor 41 executes a program to control each part of the server device 40 and perform various calculations. The processor 41 includes, for example, one or more CPUs (Central Processing Units). The memory 42 is used by the processor 41 to perform various processes. The memory 42 includes, for example, a ROM (Read Only Memory) and a RAM (Random Access Memory). The storage 43 stores various data used by the processor 41. This data includes a first table 431 and a second table 432. The storage 43 includes, for example, a HHD (Hard Disk Drive) or an SSD (Solid State Drive). The storage 43 is an example of a "storage means" according to the present invention. In addition, the memory 42 or the storage 43 stores a program for realizing the functions of the server device 40. The communication IF 44 performs data communication with other devices according to a predetermined communication standard. The input unit 45 inputs a signal according to a user's operation to the processor 41. The input unit 45 includes, for example, a keyboard and a mouse. The display unit 46 displays various information. The display unit 46 includes, for example, a liquid crystal display. The display unit 46 is an example of the "output means" according to the present invention.

The server device 40 functions as a first acquisition means 411, a first determination means 412, a second determination means 413, a third determination means 414, a generation means 415, a second acquisition means 416, an analysis means 417, an estimation means 418, and a display control means 419. These functions are realized by the processor 41 executing a program stored in the memory 42 or the storage 43.

The first acquisition means 411 acquires the main engine RPM, main shaft torque, and ship speed measured while the ship 11 is sailing from the terminal device 10. Specifically, the first acquisition means 411 transmits an acquisition request for this information to the terminal device 10. In response to this acquisition request, the terminal device 10 transmits to the server device 40 the RPM measured by the rotation measuring meter while sailing, the torque measured by the torque sensor, and the ship speed measured by the ship speed meter. The first acquisition means 411 receives the RPM, torque, and ship speed transmitted from the terminal device 10.

The first acquisition means 411 also acquires the surface roughness of the propeller 110 after the ship 11 has sailed. This surface roughness is determined by inspecting the propeller 110 while the ship 11 is moored. For example, a diver may determine the surface roughness of the propeller 110 using a lubricant gauge. Alternatively, an underwater drone may determine the surface roughness of the propeller 110 using a measuring device. The surface roughness of the propeller 110 determined in this manner is added to the voyage record of the ship 11. The first acquisition means 411 may acquire the surface roughness of the propeller 110 included in the voyage record from the terminal device 10 in a manner similar to that described above. Alternatively, a user may input the surface roughness of the propeller 110 using the input unit 45, and the first acquisition means 411 may acquire the surface roughness input by the user.

The first determination means 412 determines the increase in the torque coefficient of the propeller 110 (hereinafter referred to as the "total torque coefficient") caused by a change in the overall surface condition including the propeller 110 and the hull of the ship 11. The total torque coefficient is an example of the "first torque coefficient" according to the present invention. First, the first determination means 412 calculates the total torque coefficient using the main engine rotation speed and main shaft torque acquired by the first acquisition means 411. The total torque coefficient is calculated by the following formula (1).

Kq=Q/ρn^2D^5・・・(1)
In formula (1), Kq is the total torque coefficient, Q is the torque of the main shaft, ρ is the density of seawater, n is the rotation speed of the main engine, and D is the propeller diameter. The rotation speed of the main engine may be the average value of the rotation speed of the main engine acquired by the first acquisition means 411, or may be the last measured value. Similarly, the torque of the main shaft may be the average value of the torque of the main shaft acquired by the first acquisition means 411, or may be the last measured value. The density of seawater is a constant. The propeller diameter is a constant for each ship 11.

Then, the first determination means 412 calculates the increase in the total torque coefficient calculated this time relative to the total torque coefficient at a reference point in time, such as before sailing. The total torque coefficient at this reference point in time is calculated in advance using, for example, the initial value of the rotation speed of the main engine of the ship 11 and the initial value of the torque of the propeller 110, and is stored in the storage 43.

The second determination means 413 determines the amount of increase in the torque coefficient of the propeller 110 (hereinafter referred to as the "propeller-derived torque coefficient") caused by a change in the surface condition of the propeller 110 of the ship 11. The propeller-derived torque coefficient is an example of the "second torque coefficient" according to the present invention. First, the second determination means 413 determines the propeller-derived torque coefficient using the surface roughness of the propeller 110 acquired by the first acquisition means 411. The propeller-derived torque coefficient is found based on the relationship between the surface roughness of the propeller 110 and the performance of the propeller 110.

3 is a diagram showing an example of the relationship between the surface roughness of the propeller 110 and the performance of the propeller 110. In the graph shown in FIG. 3, the vertical axis indicates the torque coefficient, and the horizontal axis indicates the advance coefficient. Among the surface roughnesses A to E, surface roughness A is the smallest, and the surface roughness increases in the order of A, B, C, D, and E. According to this graph, when the advance coefficient is constant, as the surface roughness increases, the torque coefficient also increases. Note that, for the torque coefficient, advance coefficient, and surface roughness constituting the graph, experimental values obtained from tank tests or calculated values obtained from CFD (Computational Fluid Dynamics) numerical calculations are used in the initial state. The graph shown in FIG. 3 is created using these experimental values or calculated values. In addition, when actual measured values are obtained by the navigation of at least one ship 11, each data constituting the graph may be overwritten and updated with the actual measured values. The advance coefficient is calculated by the following formula (2).

J = Va/(n × D) ... (2)
In formula (2), J is the advance coefficient, Va is the propeller advance speed, n is the main engine RPM, and D is the propeller diameter. The main engine RPM may be the average value of the main engine RPMs acquired by the first acquisition means 411, or may be the last measured value. The propeller diameter is a constant for each ship 11. The propeller advance speed is calculated by the following formula (3).

Va = Vs × (1-w) ... (3)
In formula (3), Va is the propeller forward speed, Vs is the ship speed, and 1-w is the wake coefficient. The ship speed may be the average value of the ship speeds acquired by the first acquisition means 411, or may be the last measured value. The wake coefficient may be a constant, or may be obtained by other methods such as a method based on a tank test of a model ship, a method using an estimation chart, or a method using an approximate calculation formula. Note that as the surface roughness increases, the thrust coefficient decreases, so that in order to obtain the required ship speed, it is necessary to increase the rotation speed of the main engine. The forward speed may be obtained by taking this factor into account.

Once the forward advance coefficient is calculated using formulas (2) and (3), the second determination means 413 determines the torque coefficient corresponding to the forward advance coefficient and the surface roughness of the propeller 110 acquired by the first acquisition means 411 as the propeller-derived torque coefficient in the graph shown in Figure 3.

As another example, the second determination means 413 may determine the propeller-derived torque coefficient corresponding to the surface roughness of the propeller 110 acquired by the first acquisition means 411 based on a performance database indicating the correspondence between the surface roughness of the propeller 110 and the propeller-derived torque coefficient. This performance database is created based on the past performance of at least one ship 11 and is stored in the storage 43.

Then, the second determination means 413 calculates the increase in the propeller-derived torque coefficient calculated this time relative to the propeller-derived torque coefficient at a reference point in time, such as before sailing. The propeller-derived torque coefficient at this reference point in time is determined in advance using, for example, an initial value of the surface roughness of the propeller 110, an initial value of the RPM of the main engine of the ship 11, and an initial value of the ship speed of the ship 11, and is stored in the storage 43.

The third determination means 414 determines the increase in the torque coefficient of the propeller 110 (hereinafter referred to as the "hull-derived torque coefficient") caused by a change in the surface condition of the hull of the ship 11. The hull-derived torque coefficient is an example of the "third torque coefficient" according to the present invention. Specifically, the third determination means 414 calculates the increase in the hull-derived torque coefficient using the increase in the total torque coefficient determined by the first determination means 412 and the increase in the propeller-derived torque coefficient determined by the second determination means 413. The increase in the hull-derived torque coefficient is the difference between the increase in the total torque coefficient and the increase in the propeller-derived torque coefficient, and is calculated by the following formula (4).

ΔKq_C＝ΔKq_A－ΔKq_B・・・(4)
In equation (4), ΔKq_C is the increase in the hull-derived torque coefficient, ΔKq_A is the increase in the total torque coefficient, and ΔKq_B is the increase in the propeller-derived torque coefficient.

The generating means 415 generates effect information indicating the effect obtained when the maintenance of the propeller 110 is performed according to the increase in the propeller-derived torque coefficient, based on the first table 431 stored in the storage 43. The generating means 415 also generates effect information indicating the effect obtained when the maintenance of the hull is performed according to the increase in the hull-derived torque coefficient, based on the second table 432 stored in the storage 43.

4 is a diagram showing an example of the first table 431 and the second table 432. The first table 431 shows the correspondence relationship between the increase in the propeller-derived torque coefficient and the effect obtained by the maintenance of the propeller 110 for each type of ship 11. The first table 431 is an example of the "correspondence information" according to the present invention. The first table 431 stores the type of ship 11, the increase in the propeller-derived torque coefficient, and the maintenance effect information in association with each other. The increase in the propeller-derived torque coefficient and the maintenance effect information are obtained from the past performance of at least one ship 11. The maintenance effect information is, for example, a value indicating the proportion of the fuel consumption amount reduced by the maintenance. The maintenance effect information may also be the amount of fuel consumption reduced by the maintenance converted into the price of heavy oil. The generating means 415 reads out the maintenance effect information associated with the type of ship 11 and the increase in the propeller-derived torque coefficient determined by the second determining means 413 from the second table 432.

The second table 432 shows the correspondence between the increase in the hull-derived torque coefficient and the effect obtained by the maintenance of the hull for each type of ship 11. The second table 432 is an example of the "correspondence information" according to the present invention. The second table 432 stores the type of ship 11, the increase in the hull-derived torque coefficient, and the effect information of the maintenance in association with each other. As with the first table 431, the increase in the hull-derived torque coefficient and the effect information of the maintenance are obtained from the past performance of at least one ship 11. As with the first table 431, the effect information of the maintenance may be a value indicating the proportion of the fuel consumption reduced by the maintenance, or may be the amount of fuel consumption reduced by the maintenance converted into the price of heavy oil. The generating means 415 reads out the effect information associated with the type of ship 11 and the increase in the hull-derived torque coefficient determined by the third determining means 414 from the second table 432.

The second acquisition means 416 acquires actual navigation conditions of at least one ship 11 and planned navigation conditions of the ship 11. The actual navigation conditions are navigation conditions when at least one ship 11 has sailed in the past. The second acquisition means 416 receives the actual navigation conditions from the terminal device 10 by sending an acquisition request for the actual navigation conditions to the terminal device 10, similar to the first acquisition means 411 described above. The actual navigation conditions are an example of the "first navigation conditions" according to the present invention. The planned navigation conditions are navigation conditions planned for the ship 11. The planned navigation conditions are an example of the "second navigation conditions" according to the present invention. The second acquisition means 416 may acquire the planned navigation conditions from the terminal device 10 by the same method as described above, or may acquire the planned navigation conditions input in response to a user's operation using the input unit 45.

The analysis means 417 analyzes the correlation between the actual sailing conditions acquired by the second acquisition means 416 and the increase in the propeller-derived torque coefficient determined by the second determination means 413. The analysis means 417 also analyzes the correlation between the actual sailing conditions acquired by the second acquisition means 416 and the increase in the hull-derived torque coefficient determined by the third determination means 414. The increase in the propeller-derived torque coefficient and the increase in the hull-derived torque coefficient determined by the second determination means 413 and the third determination means 414 are the actual increase in the propeller-derived torque coefficient and the increase in the hull-derived torque coefficient affected by past sailing in accordance with the actual sailing conditions in at least one ship 11, respectively. Each correlation may be formulated. Furthermore, the analysis of the correlation may be performed using AI (Artificial Intelligence).

The estimation means 418 estimates the increase in the propeller-derived torque coefficient when the ship 11 navigates according to the planned navigation conditions acquired by the second acquisition means 416, based on the correlation between the actual navigation conditions and the increase in the propeller-derived torque coefficient. The estimation means 418 also estimates the increase in the hull-derived torque coefficient when the ship 11 navigates according to the planned navigation conditions acquired by the second acquisition means 416, based on the correlation between the actual navigation conditions and the increase in the hull-derived torque coefficient. The estimation method of the estimation means 418 may be, for example, a method of estimating the increase in the propeller-derived torque coefficient or the increase in the hull-derived torque coefficient that is correlated with the actual navigation conditions that are most similar to the planned navigation conditions in the correlation.

The display control means 419 causes the display unit 46 to display the increase in the total torque coefficient, the increase in the propeller-derived torque coefficient, and the increase in the hull-derived torque coefficient determined by the first determination means 412, the second determination means 413, and the third determination means 414, as well as the maintenance effect information generated by the generation means 415. The display control means 419 also causes the display unit 46 to display the increase in the propeller-derived torque coefficient and the increase in the hull-derived torque coefficient estimated by the estimation means 418.

5 is a flowchart showing an example of an operation of the server device 40 for analyzing the performance degradation of the ship 11. This operation is started in response to a user's operation using the input unit 45, for example, while the ship 11 is moored at a quay after sailing.

In step S101, the first acquisition means 411 acquires the main engine RPM, the torque of the main shaft of the propeller 110, and the ship speed measured while the ship 11 is sailing from the terminal device 10. The first acquisition means 411 receives this information from the terminal device 10 by sending an acquisition request for this information to the terminal device 10.

In step S102, the first determination means 412 determines the increase in the total torque coefficient. First, the first determination means 412 calculates the total torque coefficient by substituting the main engine rotation speed and torque acquired in step S101 into the above-mentioned formula (1). Next, the first determination means 412 calculates the increase in the total torque coefficient calculated this time relative to the total torque coefficient at a reference point, such as before sailing.

In step S103, the first acquisition means 411 acquires the surface roughness of the propeller 110 after sailing. The first acquisition means 411 receives the surface roughness of the propeller 110 from the terminal device 10 by transmitting a request to acquire the surface roughness of the propeller 110 to the terminal device 10. Alternatively, the user may input the surface roughness using the input unit 45, and the first acquisition means 411 may acquire the surface roughness input by the user.

In step S104, the second determination means 413 determines the increase in the propeller-derived torque coefficient. First, the second determination means 413 calculates the forward speed by substituting the ship speed acquired in step S101 into the above-mentioned formula (3). Next, the second determination means 413 calculates the forward speed and the main engine RPM acquired in step S101 into the above-mentioned formula (4) to calculate the forward coefficient. Furthermore, the second determination means 413 determines the torque coefficient corresponding to this forward coefficient and the surface roughness of the propeller 110 acquired in step S103 as the propeller-derived torque coefficient based on the graph shown in FIG. 3. Then, the second determination means 413 calculates the increase in the propeller-derived torque coefficient calculated this time relative to the propeller-derived torque coefficient at a reference point, such as before sailing.

In step S105, the third determination means 414 determines the increase in the hull-derived torque coefficient. The third determination means 414 substitutes the increase in the total torque coefficient and the increase in the propeller-derived torque coefficient determined in steps S102 and S104 into the above-mentioned formula (4) to calculate the increase in the hull-derived torque coefficient.

In step S106, the first determination means 412, the second determination means 413, and the third determination means 414 store in the storage 43 the increase in the total torque coefficient, the increase in the propeller-derived torque coefficient, and the increase in the hull-derived torque coefficient determined in steps S102, S104, and S105, respectively.

In step S107, the generating means 415 generates effect information indicating the effect of performing maintenance. For example, assume that the type of the vessel 11 is type X, the increase in the propeller-derived torque coefficient determined in step S103 is Δ1, and the increase in the hull-derived torque coefficient determined in step S105 is Δ2. In this case, the generating means 415 reads out effect information associated with type X and the increase in the propeller-derived torque coefficient Δ1 from the first table 431. The generating means 415 also reads out effect information associated with type X and the increase in the propeller-derived torque coefficient Δ2 from the second table 432.

In step S108, the display control means 419 causes the display unit 46 to display the increase in the total torque coefficient, the increase in the propeller-derived torque coefficient, and the increase in the hull-derived torque coefficient stored in the storage 43, as well as the maintenance effect information generated in step S107.

The user can see the degree of performance degradation of the vessel 11 by looking at the increase in the total torque coefficient. In addition, the user can see whether the cause of the performance degradation of the vessel 11 is due to the surface condition of the propeller 110, the surface condition of the hull, or both, by looking at the increase in the propeller-derived torque coefficient and the increase in the hull-derived torque coefficient. Therefore, the user can perform appropriate maintenance according to the cause of the performance degradation of the vessel 11, such as performing only maintenance of the propeller 110 if the cause of the performance degradation of the vessel 11 is due to the surface condition of the propeller 110. In addition, the user can see the effect of performing maintenance of the propeller 110 or the hull by looking at the maintenance effect information. Therefore, the user may prioritize the maintenance of the propeller 110 or the hull, whichever is more effective.

The operation shown in FIG. 5 is repeated, for example, for multiple ships 11, each time an inspection of each ship 11 is performed. It is preferable to inspect the ship 11 each time it is moored at a quay after a voyage, but there are cases where inspection cannot always be performed before or after a voyage. Therefore, inspection of the ship 11 may be performed at a specified timing, such as when it is moored at a quay after a specified period of time has passed or when it is moored at a specific quay. In this way, the storage 43 accumulates the increase in the total torque coefficient, the increase in the propeller-derived torque coefficient, and the increase in the hull-derived torque coefficient for multiple ships 11.

FIG. 6 is a sequence chart showing an example of an operation for analyzing the correlation between sailing conditions and the increase in torque coefficient. The performance degradation of the ship 11 is affected by the sailing conditions of the ship 11. Therefore, by analyzing the increase in the total torque coefficient, the increase in the propeller-derived torque coefficient, and the increase in the hull-derived torque coefficient of at least one ship 11 obtained by the operation for analyzing the performance degradation of the ship 11 described above, and the actual sailing conditions of the ship 11, the correlation between them can be found. This operation may be started each time the operation for analyzing the performance degradation of the ship 11 described above for one ship 11 is completed, or may be started at a specified timing, or may be started when the user performs an operation using the input unit 45 to instruct the operation for analyzing the correlation.

In step S201, the second acquisition means 416 of the server device 40 acquires actual sailing conditions from the terminal device 10 of the ship 11 that is the subject of analysis in the operation of analyzing the performance degradation of the ship 11 described above. Specifically, the second acquisition means 416 of the server device 40 receives the actual sailing conditions from the terminal device 10 by sending an acquisition request for the actual sailing conditions to the terminal device 10. The actual sailing conditions include, for example, the ship speed, route, and seawater temperature of the ship 11. In step S202, the second acquisition means 416 of the server device 40 stores the actual sailing conditions received from the terminal device 10 in the storage 43.

In step S203, the analysis means 417 of the server device 40 uses the actual navigation conditions, the increase in the propeller-derived torque coefficient, and the increase in the hull-derived torque coefficient stored in the storage 43 to analyze the correlation between the actual navigation conditions of the ship 11 and each of the increase in the propeller-derived torque coefficient and the increase in the hull-derived torque coefficient when the ship 11 navigates in accordance with the actual navigation conditions.

In step S204, the analysis means 417 of the server device 40 stores the analysis results of step S203 in the storage 43. As a result, the storage 43 stores first correlation information indicating the correlation between the actual navigation conditions and the increase in the propeller-derived torque coefficient, and second correlation information indicating the correlation between the actual navigation conditions and the increase in the hull-derived torque coefficient.

FIG. 7 is a flowchart showing an example of an operation for estimating the performance degradation of the ship 11. It is not always possible to inspect the propeller 110 every time the ship 11 is moored to a quay. If the propeller 110 is not inspected, the surface roughness of the propeller 110 cannot be determined, and the increase in the propeller-derived torque coefficient cannot be obtained, making it impossible to analyze the performance degradation of the ship 11. In such a case, an operation for estimating the performance degradation of the ship 11 is performed. This operation is started, for example, when the user performs an operation using the input unit 45 to instruct an operation for estimating the performance degradation of the ship 11 before the ship 11 sets sail.

In step S301, the second acquisition means 416 of the server device 40 acquires the planned voyage conditions of the ship 11. The planned voyage conditions may be acquired from the terminal device 10 of the ship 11, or may be input in response to a user's operation using the input unit 45.

In step S302, the estimation means 418 of the server device 40 estimates the increase in the propeller-derived torque coefficient when the ship 11 navigates in accordance with the planned navigation conditions based on the first correlation information stored in the storage 43. For example, the estimation means 418 estimates the increase in the propeller-derived torque coefficient that is correlated with the actual navigation conditions that are most similar to the planned navigation conditions in the correlation indicated by this first correlation information.

In step S303, the estimation means 418 of the server device 40 estimates the increase in the hull-derived torque coefficient when the ship 11 navigates in accordance with the planned navigation conditions based on the second correlation information stored in the storage 43. For example, the estimation means 418 estimates the increase in the hull-derived torque coefficient that is correlated with the actual navigation conditions that are most similar to the planned navigation conditions in the correlation indicated by this second correlation information.

In step S304, the display control means 419 of the server device 40 causes the display unit 46 to display the increase in the propeller-derived torque coefficient and the increase in the hull-derived torque coefficient estimated in steps S302-S303. This allows the user to know the increase in the propeller-derived torque coefficient and the increase in the hull-derived torque coefficient when the ship 11 is sailing in accordance with the planned sailing conditions. Therefore, the user can perform appropriate maintenance according to the estimated increase in the propeller-derived torque coefficient and the increase in the hull-derived torque coefficient after the ship 11 has sailed in accordance with the planned sailing conditions.

According to the embodiment described above, the increase in the propeller-derived torque coefficient and the increase in the hull-derived torque coefficient are determined and displayed separately, so that the user can distinguish and evaluate whether the cause of the performance degradation of the ship 11 is due to the surface condition of the propeller 110 or the surface condition of the hull. As a result, the user can perform appropriate maintenance according to the cause of the performance degradation of the ship 11. In addition, since the maintenance effect information is displayed, the user can clearly recognize the effect of performing maintenance, and the motivation to perform maintenance can be increased. Furthermore, even if the propeller 110 cannot be inspected to determine the surface roughness of the propeller 110, the increase in the propeller-derived torque of the propeller 110 and the increase in the hull-derived torque are estimated separately when the ship 11 navigates according to the scheduled navigation conditions, so that they can be distinguished and evaluated. As a result, even if the propeller 110 cannot be inspected, appropriate maintenance can be performed according to the increase in the propeller-derived torque of the propeller 110 and the increase in the hull-derived torque.

The above-described embodiment is an example of the present invention, and the present invention is not limited to this embodiment. The above-described embodiment may be modified as in the following modifications. In addition, two or more of the following modifications may be implemented in combination.

In the above-described embodiment, the surface roughness of the propeller 110 is an example of a value indicating the surface condition of the propeller 110, and is not limited to this. For example, the value indicating the surface condition of the propeller 110 may be the degree of contamination of the propeller 110. This degree of contamination indicates the degree of contamination caused by living organisms attached to the surface of the propeller 110. In this modified example, the degree of contamination of the propeller 110 is used instead of the surface roughness of the propeller 110. The second determination means 413 according to this modified example determines the amount of increase in the propeller-derived torque based on the relationship between the degree of contamination of the propeller 110 and the performance of the propeller 110. The method according to this modified example can also determine the amount of increase in the propeller-derived torque.

In the above-described embodiment, in the operation of estimating the performance degradation of the ship 11 shown in FIG. 7, maintenance effect information may be generated and displayed in the same manner as in the operation of analyzing the performance degradation of the ship 11 shown in FIG. 5. The generating means 415 according to this modified example generates effect information indicating the effect obtained when the maintenance of the propeller 110 is performed according to the increase in the propeller-derived torque coefficient estimated by the estimating means 418, based on the first table 431 stored in the storage 43. The generating means 415 according to this modified example generates effect information indicating the effect obtained when the maintenance of the hull is performed according to the increase in the hull-derived torque coefficient estimated by the estimating means 418, based on the second table 432 stored in the storage 43. The display control means 419 causes the display unit 46 to display the maintenance effect information generated by the generating means 415 in addition to the increase in the propeller-derived torque coefficient and the increase in the hull-derived torque coefficient estimated by the estimating means 418. According to this modified example, the user can recognize the effect of performing maintenance according to the increase in the propeller-derived torque of the propeller 110 and the increase in the hull-derived torque estimated by the estimation means 418.

In the above-described embodiment, the increase in the total torque coefficient may be estimated in addition to the increase in the propeller-derived torque coefficient and the increase in the hull-derived torque coefficient. The analysis means 417 according to this modification further analyzes the correlation between the actual sailing conditions and the increase in the total torque coefficient. The storage 43 further stores third correlation information indicating this correlation. The estimation means 418 further estimates the increase in the total torque coefficient based on this third correlation information. The display control means 419 causes the display unit 46 to display the increase in the total torque coefficient estimated by the estimation means 418 in addition to the increase in the propeller-derived torque coefficient and the increase in the hull-derived torque coefficient estimated by the estimation means 418. According to this modification, even if the propeller 110 cannot be inspected, the user can recognize the degree of performance degradation of the ship 11.

In the above-described embodiment, the display of the increase in each torque coefficient and the maintenance effect information is an example of outputting this information, and is not limited to this. For example, the server device 40 may be equipped with a speaker, and audio indicating this information may be output from the speaker. Furthermore, this information may be transmitted from the communication IF 44 to an external device. The speaker or communication IF 44 is an example of an "output means" according to the present invention. Even with the configuration according to this modified example, the user can distinguish and evaluate whether the cause of the performance degradation of the vessel 11 is due to the surface condition of the propeller 110 or the surface condition of the hull.

In the above-described embodiment, the configurations of the analysis system 1, the terminal device 10, and the server device 40 are merely examples, and are not limited to these. The functions of one device may be distributed among multiple devices, or the functions of multiple devices may be collectively carried out by one device.

In the above-described embodiment, the operations of the analysis system 1, the terminal device 10, and the server device 40 are merely examples, and are not limited to these. The order of the processing steps of the analysis system 1, the terminal device 10, and the server device 40 may be changed, or some of the processing steps may be omitted, as long as there is no contradiction.

Another embodiment of the present invention may provide a method having processing steps performed in the analysis system 1, the terminal device 10, and the server device 40. Furthermore, yet another embodiment of the present invention may provide a program executed in the terminal device 10 or the server device 40. This program may be provided by being stored in a computer-readable recording medium, or may be provided by downloading via the Internet, etc.

1: Analysis system, 10: Terminal device, 11: Ship, 40: Server device, 41: Processor, 42: Memory, 43: Storage, 44: Communication IF, 45: Input unit, 46: Display unit, 50: Communication satellite, 52: Network, 110: Propeller, 411: First acquisition means, 412: First determination means, 413: Second determination means, 414: Third determination means, 415: Generation means, 416: Second acquisition means, 417: Analysis means, 418: Estimation means, 419: Display control means

Claims

a first determination means for determining an increase in a first torque coefficient of the propeller caused by a change in an overall surface condition including a hull and a propeller of the vessel;
A first acquisition means for acquiring a value indicating a surface condition of the propeller;
second determining means for determining an increase in a second torque coefficient of the propeller caused by a change in the surface condition of the propeller using the value;
a third determination means for determining an increase in a third torque coefficient of the propeller caused by a change in the surface condition of the hull, using the increase in the first torque coefficient and the increase in the second torque coefficient;
and an output unit that outputs the increase in the second torque coefficient and the increase in the third torque coefficient.
The analyzer according to claim 1 , wherein the third determination means determines the difference between the increase in the first torque coefficient and the increase in the second torque coefficient as the increase in the third torque coefficient.
The analysis device according to claim 1 , wherein the first determination means determines the increase amount of the first torque coefficient by using a torque and a rotation speed of the propeller measured while the ship is sailing.
a storage means for storing correspondence information indicating a correspondence relationship between an increase in the second torque coefficient of at least one propeller, the increase being obtained from past performance of at least one ship, and an effect obtained by maintenance of the at least one propeller;
a generation unit that generates effect information indicating an effect obtained by the maintenance of the propeller according to an increase amount of the second torque coefficient based on the correspondence information,
The analysis device according to claim 1 , wherein the output means outputs the generated effect information.
a storage means for storing correspondence information indicating a correspondence relationship between an increase in the third torque coefficient of at least one propeller, the increase being obtained from past performance of at least one ship, and an effect obtained by maintenance of the hull of the at least one ship;
a generation unit that generates effect information indicating an effect obtained by the maintenance of the hull in accordance with the increase amount of the third torque coefficient based on the correspondence information,
The analysis device according to claim 1 , wherein the output means outputs the generated effect information.
a storage means for storing first correlation information indicating a correlation between past first voyage conditions of at least one ship and an increase in the second torque coefficient of at least one propeller actually caused by navigation in accordance with the first voyage conditions of the at least one ship, and second correlation information indicating a correlation between the first voyage conditions and an increase in the third torque coefficient of the at least one propeller actually caused by navigation in accordance with the first voyage conditions of the at least one ship;
A second acquisition means for acquiring second voyage conditions scheduled for the ship;
an estimation means for estimating an increase in the second torque coefficient and an increase in the third torque coefficient of the propeller when the ship navigates in accordance with the second navigation condition, based on the first correlation information and the second correlation information,
The analysis device according to claim 1 , wherein the output means further outputs the estimated increase in the second torque coefficient and the estimated increase in the third torque coefficient.
On the computer,
determining an increase in a first torque coefficient of the propeller caused by a change in an overall surface condition including a hull and a propeller of the vessel;
obtaining a value indicative of a surface condition of the propeller;
using the value to determine an increase in a second torque coefficient for the propeller caused by a change in surface condition of the propeller; and
determining an increase in a third torque coefficient of the propeller caused by a change in the surface condition of the hull using the first torque coefficient increase and the second torque coefficient increase;
and outputting the increase amount of the second torque coefficient and the increase amount of the third torque coefficient.