JP2009286166A - Vessel shape designing method aiming at reduction of increase of in-wave resistance, marine vessel, and program - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a marine vessel designing method capable of optimizing the reduction of increase of in-wave resistance, a marine vessel and a program. <P>SOLUTION: The marine vessel designing method includes a mutual relation setting step 1801, in which the relation of bluntness coefficient and resistance increase coefficient is set based on reflected wave; a resistance increase coefficient value calculation step 1803, in which a bluntness coefficient value calculated from a vessel shape is applied to the setting of the mutual relation step 1801 to obtain a resistance increase coefficient value; a correction step 1804, in which the bluntness coefficient value is corrected by changing the vessel shape; a corrected resistance increase coefficient calculation step 1806, in which the corrected bluntness coefficient value is applied to the setting of the mutual relation step 1801 to obtain a corrected resistance increase coefficient value; and a selection step 1808, in which the obtained corrected resistance increase coefficient value is compared with the resistance increase coefficient value obtained in the resistance increase coefficient value calculation step 1803 to select the vessel shape which indicates the bluntness coefficient value having a smaller resistance increase coefficient value. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a ship shape design method, a ship, and a program, for example, in which the resistance increase in waves is reduced.

  In order to accurately estimate the decrease in ship speed in the actual sea area, it is necessary to accurately estimate the increase in resistance in waves, which is one of the main factors that cause a decrease in ship speed.

  In a general calculation method for increasing resistance in waves, a method of adding a resistance increasing component based on reflected waves to a resistance increasing component based on ship motion is employed. Of these, an estimation formula has been proposed for the resistance component based on the reflected wave for low-speed enlarged ships. This estimation formula is based on the hypothesis that the resistance component based on the reflected wave is reduced as the bluntness coefficient (factor) is reduced. Conventionally, there are a plurality of patent documents in line with this hypothesis.

  For example, in Patent Document 1, a reflected wave reducing structure 12 that can be attached to the main hull as a unitary body or as an additional object is provided, and the reflected wave reducing structure 12 is sharpened from the original water line surface shape as shown in FIG. The technical idea of reducing the increase in wave resistance (by reducing the bluntness coefficient) is disclosed.

  In Patent Document 2, a full water draft valve 10 and a corrugated member 20 having a wedge-shaped horizontal cross section are provided between the full water draft valve 10 and the bow flare 30, and as shown in FIG. A technical idea for sharpening the bow (reducing the bluntness coefficient) and reducing the increase in resistance in waves is disclosed.

  Furthermore, in Patent Document 3, the bow shape of a large-sized enlarged ship is changed from the standard hull form T2 as shown in Fig. 1 to the optimally shaped T1 (bluntness coefficient is reduced) to reduce resistance increase in waves. The technical idea to be disclosed is disclosed.

Patent Document 4 discloses a technical idea in which a convex three-dimensional bow cap is attached to a bow valve and the bow valve portion is thickened as shown in FIG. However, the technical idea disclosed here is for the purpose of reducing the wave-making resistance, not for reducing the resistance in the waves, and the bow valve mounted is located far below the waterline. It is what is attached to.
Japanese Patent Laid-Open No. 2004-314943 JP 2007-069835 A JP 09-136686 A JP 2006-051915 A

  As described above, in the conventional techniques, the idea of resetting the bluntness coefficient to a high direction for the purpose of reducing the resistance in the waves is not disclosed at all in these conventional examples, and the bowed parts are all sharpened. The only thing that made the bluntness coefficient small.

  However, in the case of dredgers such as large container ships in recent years, there has been no example of demonstrating the relationship between the bluntness coefficient (factor) and the resistance increase coefficient in the past, and resistance in waves by reducing the bluntness coefficient (factor). There is a risk that the estimation accuracy of an increase in resistance in waves in the short wavelength region may be reduced because the estimation formula for reducing the frequency falls outside the applicable range. Neither of these prior arts was predicted to be effectively applicable to dredgers. This is because until now it has been criticized on the premise that lowering the bluntness coefficient is a measure to reduce drag in the waves.

  However, the inventors of the present application have discovered and focused on the fact that, depending on the ship, particularly the bow shape, making the bluntness coefficient uniform may not necessarily reduce the resistance in waves. Therefore, we have been investigating how to optimize the relationship between the ship shape and the reduction of resistance in the waves, and we have continued to study how to optimize it. On the other hand, it has been clarified by experiments of the present inventor that there is a numerical range in which the resistance in waves increases. This application was created as a result of these examinations and studies.

  Therefore, the present invention faces a new problem of optimizing the increase in wave resistance according to the shape of the ship, which has been overlooked in the above-described prior art. In other words, this application was made in order to provide a solution that could not be achieved by the prior art, and in particular, depending on the shape of the ship, it is also effective for the range where the resistance in waves increases by lowering the bluntness coefficient. It is another object of the present invention to provide a ship shape design method, ship, and program capable of reducing the resistance in waves and optimizing the increase in resistance in waves.

In order to achieve such an object, a ship shape designing method according to claim 1 of the present invention for reducing the increase in resistance in waves is a resistance increase coefficient K _AW based on a reflected wave defined by the following equation of the hull.
K _AW = B _f・ α ₁・ (1 + α ₂ )
B _f : Bluntness coefficient α ₁ : Drafting effect term
1 + α ₂ : In the relationship between the velocity effect term and the brandtness coefficient B _f
Burantonesu factor _{B f} is a hull shape which is 0.04 to 0.187, the Burantonesu factor _{B f} is reset to be in the range of 0.12 to 0.32, with reduced resistance increase coefficient _{K AW} low It is configured as a feature.

By providing such a configuration, when Burantonesu coefficient (Konami) _{B f} is in the form of about 0.04 to 0.187, a little larger Burantonesu factor _{B f} on the contrary to the common general knowledge, i.e. bow By enlarging the shape, a reduction in resistance increase based on the reflected wave is achieved more effectively and appropriately. That is, the past uniformly, when only the direction of the design to reduce the Burantonesu coefficient (Konami) B _f in order to reduce the resistance increase based on the reflected wave has been performed, rather reflected wave by bow shape in which The resistance based on has increased. In the present invention, based on various studies and experiments, when the bluntness coefficient (direction wave) _Bf is a shape of about 0.04 to 0.187, the bow shape is enlarged, that is, the bluntness coefficient _Bf is As a result of finding out that the resistance increase based on the reflected wave can be further reduced by increasing the value a little, the resistance increase reduction is optimized by setting the bluntness coefficient _Bf reset value in the range of 0.12 to 0.32. It is the one that has been determined.

  As a result, the estimation accuracy of the resistance increase based on the reflected wave is improved, and the design based on the correction of the resistance increase estimation method particularly in a short wavelength region which is important in a large ship is appropriately achieved.

Further, in order to achieve the above object, the ship shape designing method according to claim 2 of the present application for reducing the increase in resistance in waves sets the relationship between the bluntness coefficient _Bf and the resistance increase coefficient K _AW based on the reflected wave. A correlation setting step, a resistance increase coefficient K _AW value calculating step for obtaining a resistance increase coefficient K _AW value by applying a bluntness coefficient B _f value calculated from the hull shape to the setting of the correlation step, and changing the hull shape a correction step for correcting the Burantonesu coefficient B _f value, the modified modified Burantonesu coefficient B _f value the correlation fitting setting step obtains the corrected resistance increase coefficient K _AW value correction resistance increase coefficient K _AW value in this correction step a calculation step, and modifying the resistance increase coefficient K _AW value obtained by this correction resistance increase coefficient K _AW value calculating step said resistor Configured with a selection step of pressurizing the coefficient by comparing the K _AW value calculating said resistance increase factor K _AW value obtained in step, selecting a hull showing the Burantonesu coefficient B _f value of the resistance increase factor K Write _AW value is smaller Can also be done.

In this case, in particular, the relationship set in the correlation setting step is
(In the figure, K _AW : resistance increase coefficient (non-dimensional), B _f : bluntness coefficient (non-dimensional), F _n : fluid number (non-dimensional))
Or
(In the figure, ρ: fluid density (kg / m ³ ), g: gravitational acceleration (m / s ² ), ζa: wave amplitude (m), B: ship width (m), K _AW : resistance increase coefficient ( dimensionless), _{B f:} Burantonesu coefficient (dimensionless), _{F n:} Froude number (dimensionless))
Or
(The symbols in the figure are the same as above.)
Or
(The symbols in the figure are the same as above.)
Or
(In the table, F _n : Fluid number (dimensionless), ρ: Fluid density (kg / m ³ )
,
g: gravitational acceleration (m / s ² ), ζa: wave amplitude (m), B: ship width (m),
B _f : Brandtness coefficient (non-dimensional), K _AW : Resistance increase coefficient (non-dimensional))
Or
(The symbols in the table are the same as above.)
In each of these charts, the Brantness coefficient B _f value of 0.3 or less and the resistance increase coefficient K _AW value related thereto or B of 0.3 · ship width (m) or less. The B _f value (m) and the related 0.5ρ · g · ζ a ² · B · K _AW value (kN) may also be displayed.

By configuring as described above, after the relationship between the bluntness coefficient B _f and the resistance increase coefficient K _AW based on the reflected wave is set in the correlation setting step, the modified bluntness coefficient B _{f is} changed by variously changing the hull shape. to obtain a value, it will select the hull showing the Burantonesu coefficient B _f value of the smaller resistance increase coefficient K _AW values in the selection step. Further, in this case, the range / numerical value in which the bluntness coefficient _Bf value should be corrected is clarified specifically. For this reason, it is possible to obtain a ship shape in which the increase in resistance due to the reflected wave becomes smaller. Therefore, the estimation accuracy of the resistance increase based on the reflected wave is improved, and the correction of the resistance increase estimation method in a short wavelength region which is particularly important for a large ship is appropriately achieved.

Further, in order to achieve the above-mentioned object, a ship aiming at increasing and reducing resistance in waves according to claim 4 of the present application has a bluntness at least above the vicinity of the waterline of the hull having a bluntness coefficient _Bf of 0.04 to 0.187. It is characterized by the fact that a bow attachment with a coefficient _Bf of 0.12 to 0.32 is attached to reduce the resistance in waves.

With this configuration, when the shape of the bluntness coefficient (direction wave) _Bf is about 0.04 to 0.187, the bluntness coefficient _Bf is slightly increased contrary to the conventional technical common sense. As a result of based on the particular point of view that the reduction of the increase in resistance based on the reflected wave is achieved more effectively and appropriately by enlarging the shape of the part, specifically, the bluntness coefficient B _f reset value is set to 0. By attaching the bow attachment to the hull in the range of 12 to 0.32, the resistance increase based on the reflected wave can be reduced as a whole ship, and it can also be applied to existing ships.

Further, in order to achieve the above object, a ship which attained Waves resistance increase reduced according to Claim 5 of the present application, Burantonesu coefficient B _f is at least of the bow shape of痩型ship 0.04 to 0.187 The upper part is enlarged from the vicinity of the water line, and the bluntness coefficient _{Bf is set} to 0.12 to 0.32.

By constructing in this way, as an alternative to mounting a bow attachment to the hull that specifically sets the bluntness coefficient B _f reset value in the range of 0.12 to 0.32, the bow shape, at least from the vicinity of the waterline By enlarging the bow shape itself of the upper part, the same effect, that is, the increase in resistance based on the reflected wave can be reduced as a whole ship, and it can be applied to a new ship from the design stage.

In order to achieve the above object, a program according to claim 6 of the present application sets a relationship between the bluntness coefficient _Bf and the resistance increase coefficient K _AW based on the reflected wave and stores it in the resistance increase coefficient storage means. And a resistance increase coefficient for obtaining a resistance increase coefficient K _AW value by applying the correlation setting means to be calculated and a bluntness coefficient B _f value calculated from the hull shape to the information relating to the correlation setting read from the resistance increase coefficient storage means and K _AW value calculating means, the mutual and correction means, the modified modified Burantonesu coefficient B _f value in this correction means read from the resistance increase coefficient storage means for modifying the Burantonesu coefficient B _f value changing the hull Fixed resistance increase coefficient K _AW value calculation for obtaining the correction resistance increase coefficient K _AW values by fitting the information relating to the relationship set Compared with the step, the resistance increase coefficient K _AW value obtained by modifying the resistance increase coefficient K _AW value obtained by this correction resistance increase coefficient K _AW value calculating means and the resistance increase coefficient K _AW value calculating means, the resistance configured to function as a selecting means for selecting a hull showing the Burantonesu coefficient B _f values towards increasing the coefficient K _AW value is small.

Here, the resistance increase coefficient storage means is a RAM (random access) for storing information relating to a certain relationship defined or estimated between the bluntness coefficient B _f and the resistance increase coefficient K _AW based on the reflected wave. It is realized by a memory) or a ROM (read only memory) or other storage device.

Here, the correlation setting means defines a certain estimated relationship established between the bluntness coefficient B _f and the resistance increase coefficient K _AW based on the reflected wave, for example, by reading from a plot value of experimental data, This is realized by a subroutine or subprogram having an algorithm for outputting and storing this in the resistance increase coefficient storage means, or by storing these in a storage medium.

Here, the resistance increase coefficient K _AW value calculating means calculates the bluntness coefficient B _f value from the temporarily set hull shape, reads the correlation setting information from the resistance increase coefficient storage means, and calculates the calculated B _f value. Is applied to the correlation setting information, and is realized by a subroutine or subprogram having an algorithm for obtaining the resistance increase coefficient K _AW value, or by storing these in a storage medium.

Here, the correction means modifies the Burantonesu coefficient B _f value by changing the hull variously, subroutine or subprogram with an algorithm so as to obtain a modified Burantonesu coefficient B _f value, or storing them in a storage medium Realized by what

Here, the corrected resistance increase coefficient K _AW value calculating means is an algorithm that calculates the corrected resistance increase coefficient K _AW value by applying the corrected bluntness coefficient B _f value obtained above to the above-described correlation setting information. This is realized by a subroutine or a subprogram that is included, or by storing these in a storage medium.

Here, the selection means compares the corrected resistance increase coefficient K _AW value obtained above with the above resistance increase coefficient K _AW value, and corresponds to the bluntness coefficient B _f value with the smaller resistance increase coefficient K _AW value. This is realized by a subroutine or subprogram having an algorithm for selecting a hull shape to be selected and outputting the selected hull shape to a certain output unit, or by storing these in a storage medium.

By configuring as described above, each of the resistance increase coefficient storage means, the correlation setting means, the resistance increase coefficient K _AW value calculation means, the correction means, the corrected resistance increase coefficient K _AW value calculation means, and the selection means is a subroutine or These functions are realized as subprograms, which are executed on a general-purpose PC (personal computer), for example, so that each function can be achieved by these subroutines or subprograms even in a general-purpose computer.

According to the shape design method of the ship which attained Waves resistance increase reduced according to the present invention, the hull shape Burantonesu factor _{B f} is from 0.04 to 0.187, the Burantonesu factor _{B f} is from 0.12 to 0 reconfigure to be in the range of .32, since kept low resistance increase coefficient K _AW, even if the shape of approximately from 0.04 to 0.187 and more to reduce the resistance increase based on the reflected wave Effectively and properly achieved.

According to the shape design method of the ship which attained Waves resistance increase reduced according to the present invention, to obtain a modified Burantonesu coefficient B _f value by changing various hull shapes, Burantonesu coefficient of resistance increase factor K Write _AW value is smaller Since the hull shape showing the _Bf value is selected, a reduction in resistance increase based on the reflected wave is achieved more effectively and appropriately.

In addition to this, according to the shape design method for a ship that aims to reduce the resistance increase in waves according to the present invention, FIG. 10 to FIG. 13 (however, in FIG. 10 and FIG. 12, K _AW : resistance increase coefficient (dimensionless) ), B _f : Brandtness coefficient (non-dimensional), F _n : Froude number (non-dimensional), FIG. 11 and FIG. 13, ρ: Fluid density (kg / m ³ ), g: Gravitational acceleration (m / s ² ) , Ζa: wave amplitude (m), B: ship width (m), K _AW : resistance increase coefficient (non-dimensional), B _f : bluntness coefficient (non-dimensional), F _n : Froude number (non-dimensional)) As shown in the figure, the range / numerical value for which the bluntness coefficient _Bf value is to be corrected is specifically clarified, so that it is possible to obtain a ship shape in which the increase in resistance due to the reflected wave becomes smaller. Therefore, the estimation accuracy of the resistance increase based on the reflected wave is improved, and the correction of the resistance increase estimation method in a short wavelength region which is particularly important for a large ship is appropriately achieved.

According to the ship which attained Waves resistance increase reduced according to the present invention, when Burantonesu factor B _f is in the form of about 0.04 to 0.187, the Burantonesu factor B _f on the contrary to the common general knowledge little Therefore, it is possible to appropriately reduce the resistance increase based on the reflected wave as a whole by attaching the bow attachment to the hull that specifically sets the bluntness coefficient B _f reset value in the range of 0.12 to 0.32. Will be achieved. Furthermore, since the design based on the correction of the resistance increase estimation method is realized as a bow attachment, it can be added not only to a newly built ship but also to a ship having an existing bow type.

According to the ship aiming at increasing and decreasing the resistance in waves according to the present invention, as an alternative to attaching a bow attachment with a bluntness coefficient _Bf reset value in the range of 0.12 to 0.32, to the hull. Since the bow shape itself is enlarged in the shape, at least the upper part from the vicinity of the waterline, the resistance increase based on the reflected wave can be appropriately achieved as a whole ship.

  Furthermore, the design based on the correction of the resistance increase estimation method is appropriately achieved. In particular, the above shape can be adopted from the design stage when building a new ship.

  In this case, the effect is similarly achieved even if the enlargement is performed including the upper and lower portions in the vicinity of the water line.

According to the program of the present invention, each of the resistance increase coefficient storage means, the correlation setting means, the resistance increase coefficient K _AW value calculation means, the correction means, the corrected resistance increase coefficient K _AW value calculation means, and the selection means is a subroutine or a sub. Realized as programs and can be executed by installing them on a general-purpose PC (personal computer), for example, so that the shape design of the ship that reduces resistance in waves can be automatically processed by the program without using a dedicated machine It is realized by. If only the program is installed, the function can be realized even with a general-purpose machine, and convenience is enhanced. Further, even when a change is made, it is only necessary to change the data or algorithm of the corresponding part of the program, so that maintainability independent of the mounting machine is improved.

The best mode for carrying out the present invention will be described below with reference to the drawings. In the following, the scope necessary for explanation for achieving the object of the present invention will be schematically shown, and the scope necessary for explanation of the relevant part of the present invention will be mainly explained, and the explanation will be omitted. Are according to known techniques.
(Technical investigations and considerations leading to the invention)
As a technical investigation / examination matter leading to the present invention, an embodiment of the present invention related to a ship shape design method for increasing and decreasing resistance in waves will be described.
A First, the calculation method will be described.
(1) in regular waves resistance increases regularly wave in the resistance increase _{(R AW)} is determined by divided into resistance increase based on the motion _{(R AWM)} and resistance increase based on the reflected wave _{(R AWR)} [Expression 1] .

・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ (1)
Among these, the increase in resistance based on the reflected wave is determined by the equation [2] from the bluntness coefficient (B _f ), the draft effect term (α ₁ ), and the velocity effect term (1 + α ₂ ).

・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ (2)
here,

・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ (3)

・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ (4)

・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ (5)
I ₁ and K ₁ are the first type primary deformation Bessel function and the second type primary deformation Bessel function, respectively, I and II are the integration ranges shown in FIG. 1, ρ: fluid density, g: gravitational acceleration, ζa: incidence Wave amplitude, B: Ship width, dl: Microline element along the water surface, k: Wave number, d: Drafting, F _n ; Froude number, α: Angle of encounter between ship and wave, βw: Hull water surface Of the inclination angle.
In addition, the above [Equation 1] to [Equation 5] are well-known techniques such as “Sai Fujii, Yutaka Takahashi: Experimental research on estimation method of resistance increase in waves of a hypertrophic ship, Japan Shipbuilding Society papers, No.137. , "Showa 50".

(2) Practical correction of resistance increase in regular waves In order to improve the estimation accuracy of resistance increase in waves, the resistance increase estimation method in the short wavelength region, which is particularly important for large ships, will be corrected.

Since the hull motion is small in the short wavelength region, the resistance increase based on the reflected wave is the main factor. We will conduct a model experiment and modify the conventional estimation formula according to the following policy.
(i) The resistance increase based on the reflected wave is corrected.
(ii) Apply to oblique waves.

The experiment was conducted in the applicant's 400 m tank (model ship length 6.3 m), offshore structure test tank (model ship length 3 m), and middle tank (upright wall model).
(i) Correction of resistance increase based on reflected waves
1) Drafting influence term The dimensionless frequency is k _ed by the experiment of the upright wall model.

・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ (6)

(7)

・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ (8)
Here, ω: circular frequency of incident wave, U: ship speed.
2) Speed influence term The speed influence term (1 + α ₂ ) is assumed to be Eq. (9).

・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ (9)
Here, this velocity influence term (1 + α ₂ ) is an increase in resistance (R based on the motion obtained by calculation from the experimental value at the wavelength ship length ratio (λ / L _pp = 0.3) where the motion is small in the regular front wave. _AWm ) is subtracted and _calculated by equation (10).

・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ (10)
2 to 5 show the results of the velocity influence coefficient (C ₂ ) obtained by conducting an experiment of increasing resistance in waves using models of a container ship (captain 300 m), a car carrier (captain 190 m), and a demolition ship (captain 217 m). . From this result, in the speed range where the ship actually operates, it can be approximated well by α ₂ = C ₂ F ₂ , so m = 1 is adopted.
(ii) Extension to oblique wave Although the velocity influence coefficient obtained above is a value in a regular wave heading, the velocity influence coefficient can be obtained by the same procedure even in the oblique wave. Accordingly, if the velocity influence coefficient is obtained by conducting experiments in the oblique waves of the container ship and the car carrier ship, and this is arranged by the bluntness coefficient calculated in the oblique waves, the result is as shown in FIG.

  From this, it can be seen that in the case of a normal hull form, the velocity influence coefficient can be practically estimated by equation (11) even during oblique waves.

(11)

・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ (12)
Here, C _a and C _b are constants not depending on the Bluntness coefficient B _f.

  FIGS. 7 to 9 show the results obtained by correcting the above (i) and (ii) and obtaining an increase in resistance during regular waves for the container ship shown in Table 1. 7-9, it is (lambda); wavelength, Lpp; captain. From this result, it can be seen that the practical correction accurately estimates the experimental value when the speed is changed or in the oblique wave.

When the modification based on the above-mentioned gist of the present invention is added, the relationship between the bluntness coefficient B _f and the resistance increase coefficient K _AW based on the reflected wave is shown in FIGS. 10 to 13 (K _AW : resistance in FIGS. 10 and 12). Increase coefficient (dimensionless), B _f : Bluntness coefficient (dimensionless), F _n : Froude number (dimensionless), ρ: fluid density (kg / m ³ ), g: gravity acceleration ( m / s ² ), ζa: wave amplitude (m), B: ship width (m), K _AW : resistance increase coefficient (non-dimensional), B _f : bluntness coefficient (non-dimensional), F _n : fluid number ( Dimensionless)). Incidentally, in FIG. 11 10, 13 of FIG. 12, a constant multiple values of Burantonesu factor B _f on the horizontal axis, respectively, a constant multiplied by the value of the resistance increase coefficient K _AW based on the vertical axis in the reflected wave, Each is taken. Incidentally, the representation of FIGS. 10 to 13 is only an example, method of expressing the relationship of the resistance increase factor K _AW of the Burantonesu coefficient B _f based on this findings obtained based on the reflected wave, it is possible to freely change. In addition, these FIG. 10 to FIG. 13 can also represent the relationship between the bluntness coefficient B _f and the resistance increase coefficient K _AW as a numerical table. In this case, numerically, it is expressed as a discrete value due to the nature of the numerical table. Further, the value of the constant multiple in FIGS. 11 and 13 is also an example, and the selected constant can be appropriately changed according to the purpose of use.
(First embodiment)
Next, as a first embodiment of the present invention, a description will be given of an embodiment of the present invention related to a ship that aims to increase and decrease resistance in waves. In the following, the scope necessary for explanation for achieving the object of the present invention will be schematically shown, and the scope necessary for explanation of the essential part of the present invention will be mainly explained, and the explanation will be omitted. According to a known technique.

  FIG. 14 is a diagram conceptually showing a horizontal cross section of a ship shape of a ship aiming at increasing and reducing resistance in waves according to this embodiment, and FIGS. 15 and 16 are diagrams conceptually showing a vertical cross section of the ship. It is.

As shown in FIG. 14, the ship according to the present embodiment has a bluntness coefficient B _f and a resistance increase coefficient K based on the reflected wave as shown in FIGS. 10 to 13, which are modified based on the gist of the present invention described above. A ship 1 having a bow portion W1 having a modified shape based on the relationship with the _AW at the bow. Formed as a product. The material of the structure is not particularly limited as long as it has a certain rigidity and durability. In addition, the shape shown in this figure is only an example of the shape to be enlarged, and if the bluntness coefficient is preferably set in the range of 0.12 to 0.32, it is limited to the shape. There is no. According to the prior art, the shape swells outward in a plan sectional view from the bow portion W0 position related to the bluntness coefficient that would have been set.

  As shown in FIG. 15, the ship 1 is arranged in a range that includes at least a portion corresponding to a water surface or a draft surface height encountered during a voyage. In FIG. 15, it extends upward from the upper part of the bow B <b> 1 toward the upper deck 10 so as to include almost the entire range of the water surface position encountered in the vertical direction. By this structure, it is comprised so that the vicinity of the full load waterline and the vicinity of the lightly loaded waterline may be covered. Alternatively, as shown in FIG. 16, only the upper part may be enlarged from the vicinity of the draft surface.

In the ship 1 having such a configuration, since the bluntness coefficient is preferably set in the range of 0.12 to 0.32 at the upper part of the bow part or at least the vicinity of the draft surface of the bow part, the resistance increase based on the reflected wave is increased. Reduction is achieved more effectively and appropriately. That is, as a comparative control in the first embodiment, so far in the Burantonesu coefficient (Konami) B _f estimation set value, especially in the case of large ships, it has rather resistor based on the reflected wave got increased However, by enlarging the bow shape within a certain range, the resistance increase based on the reflected wave can be appropriately achieved, particularly in the short wavelength region, which is important for large ships.

In the above description, the case where the shape of the bow portion itself is the shape shown in FIGS. 14 to 16 has been described as an example. However, it is realized as an attachment having the above-mentioned bluntness coefficient, and the attachment (structure) is realized as the bow portion. It may be attached to (not shown). In this way, it is possible to improve the estimation accuracy of the resistance increase based on the reflected wave while taking advantage of existing ships as well as new ships, and reduce resistance increase in the short wavelength range even for large existing ships. Is achieved appropriately.

(Second Embodiment)
Next, as a second embodiment, an embodiment of the present invention relating to a program will be described, in particular, an embodiment of a program related to a ship shape design that aims to increase and decrease resistance in waves.

FIG. 17 is a functional configuration diagram of a program according to the present embodiment. As shown in the figure, the wave resistance increase / reduction program 2 according to the present embodiment includes a correlation setting unit 20, a resistance increase coefficient K _AW value calculation unit 22, a correction unit 24, and a correction resistance increase coefficient K _AW. The value calculation unit 26, the selection unit 28, the resistance increase coefficient storage unit 201, and an overall control unit 210 that performs overall control are provided. In addition, for example, a PC (personal computer) in which a program is installed separately from the program 2 has a function of inputting information, and an input unit 3 realized by a keyboard, a mouse, a voice input device, etc. And an output unit 4 having an output function and realized by a display, a printer, or the like.

The correlation setting unit 20 defines a certain relationship between the bluntness coefficient B _f and the resistance increase coefficient K _AW based on the reflected wave, for example, by reading from a plot value of experimental data, and defines this. A subroutine or subprogram having an algorithm to be output and stored in the storage unit 201.

The resistance increase coefficient K _AW value calculation unit 22 calculates a bluntness coefficient B _f value from the set hull shape, reads the correlation setting information from the resistance increase coefficient storage unit 201, and uses the calculated B _f value as the mutual value. A subroutine or subprogram having an algorithm for obtaining the resistance increase coefficient _KAW value by applying it to the relationship setting information.

Correcting unit 24 corrects the Burantonesu coefficient B _f value by changing the hull variously referred subroutine or subprogram with an algorithm so as to obtain a modified Burantonesu coefficient B _f value.

Fixed resistance increase coefficient K _AW value calculating section 26, the correction unit 24 in the resulting modified Burantonesu coefficient B _f value correlation setting unit 20 at a set interrelated set modifications resistance increase coefficient K _AW values by fitting the information A subroutine or subprogram having an algorithm for calculating.

Selecting unit 28 compares the resistance increase coefficient K _AW values obtained by modifying the resistance increase coefficient K _AW value calculating unit modifications resistance increase factor obtained in 26 K _AW and resistivity increase factor K _AW value calculating section 22, refers to a subroutine or subprogram has an algorithm that outputs a hull shape corresponding thereto to select the corresponding hull shape Burantonesu factor B _f value of the resistance increase factor K Write _AW value is smaller in the output unit 4.

The resistance increase coefficient storage unit 201 is a random access memory (RAM) for storing constant relationship information between the bluntness coefficient B _f set by the correlation setting unit 20 and the resistance increase coefficient K _AW based on the reflected wave. Memory) or ROM (Read Only Memory) or other storage device.

  Next, the operation of the program having such a configuration will be described.

FIG. 18 is a flowchart for explaining the operation of the program. As shown in the figure, first, the correlation setting unit 20 sets correlation information between the bluntness coefficient B _f and the resistance increase coefficient K _AW based on the reflected wave (step 1801). The interrelation information obtained in this way is recorded in the resistance increase coefficient storage unit 201 (step 1810).

Next, the overall control unit 210 calculates the bluntness coefficient _Bf value from the hull shape based on a fixed calculation formula (step 1802).

Then, the resistance increase coefficient _{K AW} value calculating section 22 calculates the resistance increase coefficient _{K AW} values by fitting the correlation information elicited Burantonesu coefficient _{B f} value from the resistance increase coefficient storage unit 201 (step 1803).

Next, the correcting unit 24 changes the hull shape in various ways to correct the bluntness coefficient B _f value (step 1804), checks whether the hull shape satisfies the design conditions and the construction cost, and the like, and the desired corrected brantness. Repeat until the coefficient _Bf value is obtained (step 1805).

Once the desired modifications Burantonesu coefficient _{B f} values are obtained, corrected resistance increase coefficient _{K AW} value calculating unit 26, correlation setting information set correction Burantonesu coefficient _{B f} value obtained in step 1804 and 1805 in step 1801 Is applied to the corrected resistance increase coefficient _KAW value (step 1806).

Next, the selection unit 28 compares the resistance increase coefficient _{K AW} values obtained by modifying the resistance increase coefficient _{K AW} value and steps 1803 obtained in step 1806 (step 1807).

Next, the selection unit 28 selects the hull shape corresponding to the bluntness coefficient B _f value having the smaller resistance increase coefficient K _AW value, and outputs the hull shape corresponding to this to the output unit 4 (step 1808). Then, a series of processing is completed.

As described above in detail, according to the present embodiment, the functions of mutual relationship setting, resistance increase coefficient K _AW value calculation, correction, correction resistance increase coefficient K _AW value calculation, and selection are routinely performed. The functions are realized as subroutines or subprograms, and these functions can be achieved by these subroutines or subprograms even if they are installed on a general-purpose PC (Personal Computer) and executed.

  The present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the spirit of the present invention.

  Further, the above is merely an example of an embodiment for realizing the technical idea according to the present invention, and the technical idea according to the present invention can be applied to other embodiments. is there.

  Furthermore, even if the apparatus, method, and system produced using the present invention are listed and commercialized as a secondary product, the value of the present invention is not reduced at all.

  According to the present invention, especially in the case where the resistance in the wave is effectively reduced even in a range where the resistance in the wave is increased by lowering the bluntness coefficient depending on the shape of the ship, the resistance in the wave is increased. Since the reduction can be optimized, it has great benefits for the entire shipping industry.

It is the figure which showed roughly the coordinate system for the reflected wave which concerns on the technical investigation and examination matter which leads to this invention. The figure which showed roughly the speed influence term of the resistance increase based on the reflected wave which concerns on the technical investigation and examination matter which leads to this invention (in the case of a container ship in the front direction wave, Brantness coefficient _Bf = 0.0585) It is. The figure which showed roughly the speed influence term of the resistance increase based on the reflected wave which concerns on the technical investigation and examination matter which leads to the present invention (in the case of the container ship in the inclination wave, the Brantness coefficient B _f = 0.267) is there. The figure which showed roughly the speed influence term of the resistance increase based on the reflected wave which concerns on the technical investigation and examination matter leading to the present invention (in the case of the car carrier in the front direction wave, the Brantness coefficient B _f = 0.0777) is there. The figure which showed roughly the speed influence term of the resistance increase based on the reflected wave which concerns on the technical investigation and examination matter leading to the present invention (in the case of the demolition ship in the front direction wave, Brantness coefficient B _f = 0.412) is there. It is the figure which showed roughly the speed influence coefficient of the resistance increase based on the reflected wave concerning the technical investigation and examination matter which leads to this invention. Modifications related to technical investigations and considerations leading to the present invention were made, and the resistance increase in the heading wave for the container ship shown in Table 1 (in case of Froude number F _n = 0.247, α = 0deg) It is the figure shown schematically. Make the corrections according to technical investigation and consideration leading to the present invention, with respect to container ship shown in Table 1, an increase in resistance in front Konami (the Froude number F _n = 0.200, the case of alpha = 0 deg) It is the figure shown schematically. Modifications related to technical investigations and considerations leading to the present invention were made, and the resistance increase in the head-to-side wave for the container ship shown in Table 1 (in the case of Froude number F _n = 0.247, α = 40 deg) It is the figure shown schematically. With modifications based on the spirit of the present invention and shows the relationship between the resistance increase coefficient K _AW based on the reflected wave and Burantonesu factor B _f. With modifications based on the spirit of the present invention and shows the relationship between the resistance increase coefficient K _AW based on the reflected wave and Burantonesu factor B _f. With modifications based on the spirit of the present invention and shows the relationship between the resistance increase coefficient K _AW based on the reflected wave and Burantonesu factor B _f. With modifications based on the spirit of the present invention and shows the relationship between the resistance increase coefficient K _AW based on the reflected wave and Burantonesu Factor B _f. It is a figure which shows notionally the horizontal cross section of the ship shape of the ship which aimed at the resistance increase in waves which concerns on the 1st Embodiment of this invention. It is a figure which shows notionally the vertical cross section of the ship shape of the ship which aimed at the resistance increase in waves which concerns on the 1st Embodiment of this invention. It is a figure which shows notionally the vertical cross section of the ship shape of the ship which aimed at the resistance increase in waves which concerns on the 1st Embodiment of this invention. It is a functional block diagram which concerns on the program for performing the ship shape of the ship which aimed at the resistance increase in waves which concerns on the 2nd Embodiment of this invention. It is a flowchart for demonstrating operation | movement of the program which concerns on the 2nd Embodiment of this invention.

Explanation of symbols

2 Wave resistance increase reduction program, 3 input section, 4 output section, 20 correlation setting section, 22 resistance increase coefficient K _AW value calculation section, 24 correction section, 26 correction resistance increase coefficient K _AW value calculation section, 28 selection section , 201 Resistance increase coefficient storage unit, 210 Overall control unit

Claims (6)

Resistance increase coefficient K _AW based on the reflected wave defined by the following equation of the hull
K _AW = B _f・ α ₁・ (1 + α ₂ )
B _f : Bluntness coefficient α ₁ : Drafting effect term
1 + α ₂ : In the relationship between the velocity effect term and the brandtness coefficient B _f
Burantonesu factor _{B f} is a hull shape which is 0.04 to 0.187, the Burantonesu factor _{B f} is reset to be in the range of 0.12 to 0.32, with reduced resistance increase coefficient _{K AW} low A ship shape design method that aims to reduce and increase resistance in waves. A correlation setting step for setting the relationship between the brandness coefficient B _f and the resistance increase coefficient K _AW based on the reflected wave, and a bluntness coefficient B _f value calculated from the hull shape is applied to the setting of the correlation step to increase the resistance increase coefficient K _AW and resistance increase coefficient K _AW value calculation step of obtaining a value, and modifying step of modifying the Burantonesu coefficient B _f value changing the hull shape, the modified modified Burantonesu coefficient B _f values in this modification step of the correlation step a modified resistance increase coefficient K _AW value calculation step of obtaining a correction resistance increase coefficient K _AW values fit to set the resistance increase coefficient K with modified resistance increase coefficient K _AW value obtained by this correction resistance increase coefficient K _AW value calculation step comparing the resistance increase coefficient K _AW value obtained by _AW value calculation step, the resistance increase coefficient K _AW value Shape design method of the ship which attained Waves resistance increase reduced with a selection step of selecting a hull showing the Burantonesu coefficient B _f value again side. The relationship set in the correlation setting step is
(In the figure, K _AW : resistance increase coefficient (non-dimensional), B _f : bluntness coefficient (non-dimensional), F _n : fluid number (non-dimensional))
Or
(In the figure, ρ: fluid density (kg / m ³ ), g: gravitational acceleration (m / s ² ), ζa: wave amplitude (m), B: ship width (m), K _AW : resistance increase coefficient ( dimensionless), _{B f:} Burantonesu coefficient (dimensionless), _{F n:} Froude number (dimensionless))
Or
(The symbols in the figure are the same as above.)
Or
(The symbols in the figure are the same as above.)
Or
(In the table, F _n : Froude number (dimensionless), ρ: Fluid density (kg / m ³ )
,
g: gravitational acceleration (m / s ² ), ζa: wave amplitude (m), B: ship width (m),
B _f : Brandtness coefficient (non-dimensional), K _AW : Resistance increase coefficient (non-dimensional))
Or
(The symbols in the table are the same as above.)
In each of these charts, the Brantness coefficient B _f value of 0.3 or less and the resistance increase coefficient K _AW value related thereto or B of 0.3 · ship width (m) or less. The B _f value (m) and the related 0.5ρ · g · ζa ² · B · K _AW value (kN) are also displayed, and the resistance increase in waves is reduced according to claim 2. Ship shape design method. The top than at least the water line near the hull Burantonesu factor _{B f} is from 0.04 to 0.187, that Burantonesu factor _{B f} is decreased mounting and Waves resistor bow wearable object to be from 0.12 to 0.32 A ship designed to reduce and increase resistance in the waves. The bluntness coefficient _Bf is enlarged from at least the vicinity of the waterline of the bow shape of a dredger with a dredge of 0.04 to 0.187, and the bluntness coefficient _{Bf is set} to 0.12 to 0.32. A ship designed to reduce and increase resistance in waves. Computer
Correlation setting means for setting the relationship between the brandness coefficient B _f and the resistance increase coefficient K _AW based on the reflected wave and storing it in the resistance increase coefficient storage means;
And resistance increase coefficient K _AW value calculating means for determining the resistance increase coefficient K _AW values by fitting the Burantonesu coefficient B _f value calculated from the hull shape on the correlation according to the setting information read from the resistance increase coefficient storing means,
Correcting means for changing the hull shape and correcting the bluntness coefficient B _f value;
Modified modified Burantonesu coefficient B the _f value determining a correction resistance increase coefficient K _AW values by fitting the information relating to the correlation set read from the resistance increase coefficient storage means modifying the resistance increase coefficient K _AW value in this correction means A calculation means;
Comparing the resistance increase coefficient K _AW value obtained by modifying the resistance increase coefficient K _AW value obtained by this correction resistance increase coefficient K _AW value calculating means and the resistance increase coefficient K _AW value calculating means, the resistance increase factor K program for functioning as a selecting means for selecting the hull shape shown towards the Burantonesu coefficient B _f value of _AW value is small.