Ship maneuverability prediction method, system and device by counting propeller performance change in regular waves

Abstract

The invention discloses a ship maneuverability prediction method, a ship maneuverability prediction system and a ship maneuverability prediction device taking propeller performance changes into regular waves. The method comprises the following steps: firstly, calculating the motion response, the second-order wave drift force and the drift moment of a ship body under different regular wave conditions based on a potential flow theory, establishing a wave force fitting equation taking the wave direction and the navigational speed as variables, and performing ship manipulation motion numerical simulation in regular waves based on an obtained calculation result; acquiring an input parameter range of the propeller in a manipulating motion state; establishing a CFD numerical model of ship propeller performance in regular waves, simulating heaving and pitching motion of the propeller under motion response, determining the range of the heaving and pitching motion, and calculating propeller thrust data under different wave conditions and input parameters; and carrying out regression analysis on the propeller thrust data, and fitting to obtain a prediction formula of the propeller thrust coefficient in the regular waves. The formula couples the wavelength-to-length ratio, the advance speed coefficient and the wave direction angle, and quantifies the dynamic influence of the wave on the propeller thrust.

Description

Technical Field

[0001] This invention specifically relates to a method, system, and device for predicting ship maneuverability in regular waves by taking into account changes in propeller performance, belonging to the field of ship and marine engineering hydrodynamics technology. Background Technology

[0002] Predicting ship maneuvering motions in waves is one of the core issues in ship hydrodynamics research. Currently, two main methods are used in engineering: one is self-propulsion maneuvering motion simulation based on computational fluid dynamics (CFD), which has high accuracy but huge computational cost; the other is numerical simulation based on mathematical models of maneuvering motion, such as the MMG model, which obtains the ship's maneuvering trajectory and various motion parameters by solving the maneuvering motion equations that take wave loads into account. This method has high computational efficiency, but does not effectively take into account the dynamic impact of waves on the propeller-rudder system.

[0003] However, existing mathematical models for maneuvering have significant limitations when applied to wave environments. While considerable research has been conducted on the hydrodynamic forces acting on the hull in waves, the hydrodynamic characteristics of appendages such as propellers and rudders are typically estimated using models developed under still water conditions. This simplification fails to accurately describe the impact of wave presence and its induced swaying motion on the aft flow field, particularly neglecting the periodic variations in propeller inflow velocity. All existing models assume the propeller operates in still water, ignoring the dynamic modulation of propeller inflow velocity, wake fraction, and thrust coefficient by wave-induced hull heave / pitch motion. Accurate propeller thrust estimation is crucial for ship maneuvering prediction. Inaccurate thrust calculations not only lead to errors in predicting longitudinal velocity but also indirectly cause inaccurate rudder force calculations, severely impacting the trajectory and state prediction of the entire maneuver. This results in significant deviations in propeller load and power consumption predictions in wave-enhanced maneuvering environments.

[0004] Therefore, a method to solve the above-mentioned technical problems is urgently needed. Summary of the Invention

[0005] To address the problems mentioned in the background section, the present invention aims to provide a method for predicting ship maneuverability in regular waves by taking into account propeller performance variations, comprising the following steps:

[0006] S1. Based on potential flow theory, calculate the motion response, second-order wave drift force and drift moment of the hull under different regular wave conditions, and establish wave force fitting equations with wave direction and speed as variables.

[0007] S2. Based on the calculation results obtained in S1, perform numerical simulation of ship maneuvering motion in regular waves to obtain the range of input parameters of the propeller under maneuvering motion state.

[0008] S3. Establish a CFD numerical model of the propeller performance in regular waves, simulate the heave and pitch motion of the propeller under the motion response described in step S1 and determine the range of the heave and pitch motion, and calculate the propeller thrust data under different wave conditions and the input parameters described in step S2.

[0009] S4. Perform regression analysis on the propeller thrust data calculated in step S3, and obtain the prediction formula for the propeller thrust coefficient in regular waves:

[0010]

[0011] In the above formula, K T This represents the propeller thrust coefficient in still water. This represents the wave influence factor, and the formula for calculating the wave influence factor is:

[0012]

[0013] In the above formula, λ / L represents the wavelength-to-length ratio, J represents the propeller advance coefficient, χ represents the wave direction angle, and C1, C2, C3, C4, and C5 represent constants obtained through regression analysis.

[0014] Preferably, in step S1, the wave conditions include wavelength, wave height, and wave direction angle, and the motion response includes the motion response amplitude operator (RAO) for heave and roll motions and their phases.

[0015] Preferably, the input parameters of the propeller include the hull speed and the propeller effective wake fraction.

[0016] Preferably, in step S3, the overlapping mesh technology and rigid body motion module of CFD software are used to define a multi-region computational domain, and the heave and pitch forced motion determined by RAO are applied to the propeller.

[0017] The present invention also provides a ship maneuverability prediction system that takes into account propeller performance changes in regular waves, for implementing the above method, comprising:

[0018] The potential flow calculation module is used to calculate the hull's motion response, second-order wave drift force, and drift torque under different regular wave conditions;

[0019] The maneuvering motion simulation module is used to perform numerical simulation of ship maneuvering motion in regular waves to obtain the range of input parameters for the propeller under maneuvering motion conditions.

[0020] The CFD calculation module is used to establish a CFD numerical model of the propeller performance of a ship in regular waves and to calculate propeller thrust data under different wave conditions and input parameters.

[0021] The data regression analysis and fitting module is used to perform regression analysis on the calculated propeller thrust data and fit it to obtain a prediction formula for the propeller thrust coefficient in regular waves.

[0022] The present invention also provides a ship maneuverability prediction device that takes into account the changes in propeller performance in regular waves. It integrates the ship maneuverability prediction system described above and embeds the prediction formula of the propeller thrust coefficient into the MMG maneuverability model for numerical prediction of ship maneuvering motion in regular waves.

[0023] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0024] I. This invention introduces a wave influence factor and establishes a propeller thrust prediction formula based on the wavelength-to-length ratio, propeller advance coefficient, and wave direction angle. This quantifies the dynamic influence of regular waves on propeller thrust and solves the problem of insufficient prediction accuracy caused by the simplified processing of propeller hydrodynamic characteristics in the prior art.

[0025] Second, this invention employs a technical approach combining "potential flow calculation + maneuverability modeling + CFD simulation + formula fitting," balancing computational accuracy and efficiency. CFD simulation ensures data reliability, and the fitting formula is easily embedded into existing MMG models without incurring significant additional computational costs. Considering the dynamic modulation effect of wave-induced hull heave / pitch motion on propeller inflow velocity, wake fraction, and thrust coefficient, it significantly improves the accuracy of propeller thrust prediction in waves. Furthermore, the simulation conditions cover various wavelengths, speeds, and wave angles. The formula structure is concise, the physical meaning of the parameters is clear, and its applicability is wide. Verification shows a high goodness of fit, accurately reflecting the nonlinear variation trend of the propeller thrust coefficient.

[0026] Third, it is applicable to propeller thrust prediction under different regular wave conditions, providing key technical support for high-precision prediction of ship maneuvering motion in waves, and can be applied to engineering scenarios such as ship design and navigation safety assessment. Attached Figure Description

[0027] For ease of explanation, the present invention will be described in detail below with reference to specific embodiments and accompanying drawings.

[0028] Figure 1 A schematic diagram of a method for predicting ship maneuverability in regular waves by taking into account changes in propeller performance.

[0029] Figure 2 This is a schematic diagram of the wave direction angle defined in the embodiments of the present invention;

[0030] Figure 3(a) is a curve of the second-order wave force fitting of the hull in the x-direction calculated in the embodiment of the present invention;

[0031] Figure 3(b) is a curve of the second-order wave force in the y-direction of the hull calculated in the embodiment of the present invention.

[0032] Figure 3(c) is a curve of the second-order wave moment in the z-direction of the hull calculated in the embodiment of the present invention.

[0033] Figure 4 This is a schematic diagram of the fixed coordinate system and the body coordinate system used to describe the motion of the ship in an embodiment of the present invention;

[0034] Figure 5 This is a schematic diagram illustrating the speed change of the ship in regular waves according to an embodiment of the present invention;

[0035] Figure 6 This is a schematic diagram illustrating the variation of propeller wake fraction in regular waves according to an embodiment of the present invention;

[0036] Figure 7 This is a schematic diagram of the propeller heave motion in an embodiment of the present invention;

[0037] Figure 8 This is a schematic diagram of the propeller pitching motion in an embodiment of the present invention;

[0038] Figure 9 This is a schematic diagram of the computational domain settings and boundary conditions for propeller CFD calculations in an embodiment of the present invention. Detailed Implementation

[0039] To make the objectives, technical solutions, and advantages of this invention clearer, the invention is described below with reference to specific embodiments shown in the accompanying drawings. However, it should be understood that these descriptions are merely exemplary and not intended to limit the scope of the invention. Furthermore, descriptions of well-known structures and technologies are omitted in the following description to avoid unnecessarily obscuring the concept of the invention.

[0040] It should also be noted that, in order to avoid obscuring the invention with unnecessary details, only the structures and / or processing steps closely related to the solution according to the invention are shown in the accompanying drawings, while other details that are not closely related to the invention are omitted.

[0041] Specific Implementation Method 1: This invention provides a method for predicting ship maneuverability in regular waves by taking into account changes in propeller performance, including the following steps:

[0042] S1. Based on potential flow theory, the motion response, second-order wave drift force, and drift moment of the hull under different regular wave conditions are calculated. A wave force fitting equation with wave direction and speed as variables is established. Preferably, this embodiment relies on the frequency domain calculation module in ANSYS AQWA software to sheet the existing hull model. Based on potential flow theory, considering the calculation problem of wetted surfaces, it is necessary to divide the waterline and align the waterline at the z=0 plane. On the other hand, for the frequency domain calculation module in ANSYS AQWA, the mesh size determines the spatial dispersion and wavelength resolution of the calculation process, and affects the range of values ​​and the number of points in the final result. The mesh smoothness is set to high, the minimum mesh size is designed to be about 1 / 380 of the ship length, the maximum mesh size is designed to be about 1 / 290 of the ship length, and the mesh growth rate is 1.2. This invention calculates the motion response, second-order wave drift force, and drift moment under multi-angle and multi-velocity conditions. The wave direction is defined as follows: Figure 2 As shown in Figure 3, the calculated second-order wave forces are fitted into equations with wave direction and speed as variables for subsequent maneuverability numerical simulations.

[0043] S2. Based on the calculation results obtained in S1, perform numerical simulation of ship maneuvering motion in regular waves to obtain the range of input parameters of the propeller under maneuvering motion state.

[0044] This embodiment establishes a three-degree-of-freedom mathematical model of ship maneuvering motion, including pitch, sway, and yaw, with its coordinate system defined as follows: Figure 4 As shown in the diagram. O0x0y0z0 is a fixed spatial coordinate system, with point O0 fixed at a point on Earth. O0x0 points due north, and O0y0 points due east. Oxyz is a body-following coordinate system, which moves with the ship's motion. O is fixed within the ship's center, Ox points towards the bow, and Oy points to the right of the bow. The Oxy plane is at sea level.

[0045] Based on the Newton-Euler equations, the dynamic equations for the three free motions of the ship are as follows:

[0046]

[0047] Based on coordinate transformation, the kinematic equations for the three-degree-of-freedom motion of the ship can be established as follows:

[0048]

[0049] Where u, v, and r represent the velocities in the x, y, and z directions, respectively; m x and m y J represents the added mass of the manipulation motion in the x and y directions, respectively; zz The additional moment of inertia represents the heading direction, and ψ represents the heading angle.

[0050] Preferably, for forces and moments X, Y, and N, the present invention adopts the MMG model expression:

[0051]

[0052] In this model, the subscripts 'H', 'P', and 'R' represent the hull, propeller, and rudder, respectively. The subscript 'W' represents the wave, which is substituted into the second-order wave drift force and drift moment calculated based on potential flow theory in Part 1. The hydrodynamic model for the hull and rudder continues to use the hydrodynamic model in still water, and the specific form for the hull is as follows:

[0053]

[0054] Where X' vv 、X' vr 、X' rr Y' v Y' r Y' vvv Y' vvr Y' vrr Y' rrr 、N' v 、N' r 、N' vvv 、N' vvr 、N' vrr 、N' rrr Represents hydrodynamic parameters, which can be obtained from constrained model tests; C0 represents the hydrostatic drag coefficient experienced by the hull; X' H Y' H and N' H represent the dimensionless forms of force and torque, respectively; v' and r' are the dimensionless forms of v and r, respectively. The dimensionless method used in this paper is as follows:

[0055]

[0056]

[0057] Where ρ represents the density of water; L represents the length of the ship; d represents the width of the ship; and V represents the speed of the ship.

[0058] For propellers

[0059]

[0060] Among them, t P K represents the thrust reduction factor; n represents the propeller speed in rps; D represents the propeller diameter. T The propeller thrust coefficient is represented by the following expression:

[0061]

[0062] In the above formula, k 0(T) and k 1(T) These are the parameters of the fitting curve for the propeller thrust coefficient and advance coefficient, which are affected by heave and pitch motion; J represents the propeller advance coefficient, and its specific expression is: Among them, V S Represents propeller advance speed; ω P The effective wake fraction of the propeller under maneuvering conditions.

[0063] Under ship maneuvering conditions, changes in the ship's motion state cause significant changes in the inflow behind the ship, thus affecting the ship-propeller interaction coefficient, namely thrust deduction and wake fraction. Thrust deduction characterizes the increased water velocity at the stern caused by the suction effect of the propeller rotation, leading to increased hull drag. Generally, thrust deduction is considered to be minimally affected by maneuvering conditions and can still be considered a constant value. On the other hand, the wake fraction, which characterizes the impact of ship turbulence on the propeller inflow, changes significantly and cannot be simply applied using the still water effective wake fraction. Preferably, this invention uses the following formula to estimate the wake fraction under maneuvering conditions: In the formula, c P ω is the calculation factor. P0 The effective wake fraction in straight flight mode; β P The propeller inlet angle is defined as follows: In the formula, x p ' This is the dimensionless form of the longitudinal position of the propeller.

[0064] Furthermore, unlike the uniform straight-line sailing state, the propeller inlet under maneuvering conditions is not uniform, resulting in significant differences and periodic variations in the blade load at different positions, thus generating a significant lateral force. The relevant equation for propeller lateral force in this invention is as follows: ; In the formula, c YP β is the propeller lateral force coefficient; l is the drift angle; ' P x is the correction factor for the turning motion. P This represents the longitudinal position of the propeller.

[0065] The description of the rudder force and torque is as follows:

[0066]

[0067] Where δ is the rudder angle; x R The x-coordinate of the point of application of the normal force of the rudder; FN Normal rudder force; t R The drag reduction factor represents the drag caused by changes in rudder angle; x H and α H This is the interaction coefficient between the rudder and the hull, related to the lateral force caused by the rear flow field induced by the circulation on the rudder during rudder turning. The normal rudder force F... N The formula is:

[0068] In the above formula, A R Λ is the rudder area. R For the span ratio; V R α is the rudder inflow velocity. R The inflow angle of the rudder, V R and α R The defining formula is:

[0069]

[0070]

[0071] Among them, u R and v R Let be the longitudinal and lateral components of the rudder inflow velocity. The expressions are as follows:

[0072]

[0073] Where ε is the ratio of the wake velocity in front of the rudder to the wake velocity in front of the propeller; ω p For effective accompaniment fraction; η p γ is the percentage of the rudder area located in the propeller wake. R κ is the rectification coefficient; κ is the rudder-propeller interference coefficient.

[0074] Changes in hull velocity and wake fraction in regular waves, such as Figure 5 and Figure 6 As shown, the velocities are divided into V / V0 = 0.7, 0.5, 0.45, and 0.4. Furthermore, since the wake fraction is too small, it is preferable to select a wake fraction of 0, where V0 = 2.196 (Fr = 0.26).

[0075] S3. Establish a CFD numerical model of the propeller performance in regular waves, simulate the heave and pitch motion of the propeller under the motion response described in step S1 and determine the range of the heave and pitch motion, and calculate the propeller thrust data under different wave conditions and the input parameters described in step S2.

[0076] Based on the motion module of STAR-CCM+, forced motion can be applied to the propeller. Using overlapping mesh technology, a computational domain including a rotation domain, a motion domain, and an outer domain is constructed to address the mesh adaptability problem of propeller heave and pitch motions. The propeller, under a uniform inflow, is superimposed with the forced heave and pitch motions determined by the RAO obtained in step S1. The motion equations are as follows:

[0077] Swaying motion:

[0078] Pitching motion:

[0079] Among them, A h It is the amplitude of the heave motion; φ h It is the phase of the heave motion; θ p It is the amplitude of the pitching motion, measured in rad; φ p ω is the phase of the heave motion; ω is the frequency of the heave and pitch motion. A schematic diagram of propeller heave and pitch motion is shown below. Figure 7 and Figure 8 As shown in the figure. Overlapping meshes are selected for subsequent numerical simulations. The overlapping mesh method can effectively handle the mesh adaptability problem caused by motion and overcome the limitations of other methods in terms of geometric motion, thus making it more suitable for simulating unsteady flows. To consider overlapping meshes and propeller motion, a computational domain consisting of three regions is adopted. The rotational domain, the innermost region, simulates the propeller's heave and pitch motion. The propeller motion domain, the middle region, defines the range of heave and pitch motion and uses mesh refinement techniques to improve the accuracy of flow field prediction. The outermost region represents the entire fluid domain. The dimensions and boundary conditions of each region are as follows: Figure 9 As shown. On the other hand, considering the hydrostatic resistance of the hull and the increased drag from waves, the corresponding self-propulsion speed of the propeller can be calculated using the following formula:

[0080]

[0081]

[0082]

[0083]

[0084] In the above formula, T is the propeller thrust, and V S To design the ship speed, ω p0 R is the fraction of the accompanying flow. c For KCS hydrostatic resistance, R w To increase resistance to waves; t p The thrust of the hull is reduced. The final propeller speed n is then calculated. K T (J) may, but is not limited to, using the static water theory calculation method.

[0085] This invention also provides a specific verification method. After performing grid verification, time step verification, and open-water experiment verification, the RAO and its corresponding phase from the first part, along with the calculated self-propelled propeller speed and propeller advance speed, are used as propeller motion inputs. Furthermore, the ranges of speed and wake fraction confirmed in the second part are substituted, and considering different wavelengths and wave directions, the operating conditions shown in Table 1 are selected as sampling points to calculate heave and pitch motion at different speeds and encounter angles.

[0086] Table 1. Ship Turning Calculation Matrix in Waves

[0087]

[0088] S4. Perform regression analysis on the propeller thrust data calculated in step S3, and obtain the prediction formula for the propeller thrust coefficient in regular waves:

[0089]

[0090] This formula quantifies the dynamic impact of regular waves on the propeller thrust coefficient, reflecting the correction factor for propeller thrust under wave conditions relative to still water conditions. In the above formula, K... T This represents the propeller thrust coefficient in still water. This represents the wave influence factor, and the formula for calculating the wave influence factor is:

[0091]

[0092] In the above formula, λ / L represents the wavelength-to-length ratio, reflecting the influence of wave scale on propeller performance; J represents the propeller advance coefficient, characterizing the propeller's operating state; and χ represents the wave direction angle, characterizing the influence of wave direction on propeller inflow. C1, C2, C3, C4, and C5 are empirical coefficients obtained through regression analysis. These empirical coefficients are determined based on operating points, with different numbers of operating points corresponding to different empirical coefficients. This formula shows that the thrust coefficient, based on the still water value, is corrected by a sinusoidal wave term related to wavelength, advance coefficient, and wave direction angle. This formula is the first to couple wave scale, propeller operating state, and wave direction angle, constructing a quantitative model suitable for propeller thrust prediction in regular waves. Specifically, based on the operating condition list in Table 1, which includes multiple operating points with different advance coefficients, wavelengths, and wave angles, CFD calculations were performed under each operating condition. The obtained propeller thrust coefficient results were compared with the thrust coefficient in still water. The propeller thrust coefficient data obtained from all operating conditions under CFD calculations were organized and analyzed. Using the still water thrust coefficient as a benchmark, the wavelength-to-length ratio, propeller advance coefficient, and wave angle wave influence factor were defined. Through multivariate nonlinear regression analysis of the relationship between the still water thrust coefficient and the independent variables, the corresponding empirical coefficients were obtained. The wave influence factor formula obtained from the regression in this embodiment is as follows:

[0093] .

[0094] Specific Implementation Method Two: The contents not mentioned in this implementation method are the same as those in Specific Implementation Method One. In step S1, the wave conditions include wavelength, wave height and wave direction angle, and the motion response includes the motion response amplitude operator (RAO) of heave and pitch motion and its phase.

[0095] Specific implementation method three: The contents not mentioned in this implementation method are the same as those in specific implementation method one or two. The input parameters of the propeller include the ship speed and the propeller effective wake fraction.

[0096] Specific Implementation Method Four: The contents not mentioned in this implementation method are the same as those in Specific Implementation Method One, Two or Three. In step S3, the overlapping mesh technology and rigid body motion module of CFD software are used to define a multi-region computational domain and apply heave and pitch forced motion determined by RAO to the propeller.

[0097] The present invention also provides a ship maneuverability prediction system that takes into account propeller performance changes in regular waves, for implementing the above method, comprising:

[0098] The potential flow calculation module is used to calculate the hull's motion response, second-order wave drift force, and drift torque under different regular wave conditions;

[0099] The maneuvering motion simulation module is used to perform numerical simulation of ship maneuvering motion in regular waves to obtain the range of input parameters for the propeller under maneuvering motion conditions.

[0100] The CFD calculation module is used to establish a CFD numerical model of the propeller performance of a ship in regular waves and to calculate propeller thrust data under different wave conditions and input parameters.

[0101] The data regression analysis and fitting module is used to perform regression analysis on the calculated propeller thrust data and fit it to obtain a prediction formula for the propeller thrust coefficient in regular waves.

[0102] The present invention also provides a ship maneuverability prediction device that takes into account the changes in propeller performance in regular waves. It integrates the above-mentioned ship maneuverability prediction system and embeds the prediction formula of propeller thrust coefficient into the MMG maneuverability model for numerical prediction of ship maneuvering motion in regular waves.

[0103] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the present invention as claimed. The scope of protection of this invention is defined by the appended claims and their equivalents.

Claims

1. A method of predicting maneuverability of a ship in regular waves taking into account changes in propeller performance, characterized by, The method comprises the following steps: S1, calculating the motion response, second-order wave drift force and drift moment of the ship under different regular wave conditions based on potential flow theory, and establishing a wave force fitting equation with wave direction and speed as variables; S2, based on the calculation results obtained in S1, performing numerical simulation of ship maneuvering motion in regular waves to obtain the input parameter range of the propeller under the maneuvering motion state; S3, establishing a CFD numerical model of the propeller performance in regular waves, simulating the heave and pitch motion of the propeller under the motion response described in S1 and determining the range of heave and pitch motion, and calculating the propeller thrust data under different wave conditions and the input parameters described in S2; S4, performing regression analysis on the propeller thrust data calculated in S3 to obtain the prediction formula of the propeller thrust coefficient in regular waves as follows: ； In the above formula, K T represents the propeller thrust coefficient in still water, represents the wave influence factor, which is solved by the formula: ； In the above formula, λ / L represents the wavelength length ratio, J represents the propeller advance coefficient, χ represents the wave direction angle; C1, C2, C3, C4 and C5 represent constants obtained by regression analysis.

2. The method of predicting maneuverability of a ship in regular waves taking into account changes in propeller performance according to claim 1, characterized in that, In S1, the wave conditions include wavelength, wave height and wave direction angle, and the motion response includes the motion response amplitude operator (RAO) and phase of heave and pitch motion.

3. The method of predicting maneuverability of a ship in regular waves taking into account changes in propeller performance according to claim 2, characterized in that, The input parameters of the propeller include the ship speed and the propeller effective wake fraction.

4. The method of predicting maneuverability of a ship in regular waves taking into account changes in propeller performance according to claim 3, characterized in that, In S3, the CFD software's overlapping grid technology and rigid body motion module are used to define a multi-region calculation domain, and the heave and pitch forced motion determined by the RAO is applied to the propeller.

5. A system for predicting the maneuverability of a ship in regular waves taking into account the changes in propeller performance, for implementing the method according to any one of claims 1 to 4, characterized in that, It comprises: a potential flow calculation module for calculating the motion response, second-order wave drift force and drift moment of the ship under different regular wave conditions; a maneuvering motion simulation module for performing numerical simulation of ship maneuvering motion in regular waves to obtain the input parameter range of the propeller under the maneuvering motion state; a CFD calculation module for establishing a CFD numerical model of the propeller performance in regular waves and calculating the propeller thrust data under different wave conditions and input parameters; a data regression analysis and fitting module for performing regression analysis on the calculated propeller thrust data and fitting the prediction formula of the propeller thrust coefficient in regular waves.

6. A device for predicting the manoeuvrability of a ship in regular waves taking into account the change in propeller performance, characterised in that, The ship maneuverability prediction system of claim 5 is integrated, and the prediction formula of the propeller thrust coefficient of claim 1 is embedded into the MMG maneuverability model for numerical prediction of ship maneuvering motion in regular waves.

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