RU2746488C1 - Method of determining underwater object positioning hydrodynamic characteristics - Google Patents

Abstract

FIELD: shipbuilding.

SUBSTANCE: invention relates to production of underwater vehicles and can be used for prediction of trajectories of underwater vehicles performing complex maneuvering. Inner computational grid around three-dimensional electronic model of underwater object is shaped to spherical shape with center of sphere coinciding with point of rotation. Aft horizontal sternplanes (SP), upper vertical rudder (UVR), lower vertical rudder (LVR), bow diving planes (BDP) or fairwater diving planes (FDP) forming local deformable computational grids with the possibility of shifting SP by an angle δ_SP, UVR at angle δ_UVR, LVR at angle δ_LVR, BDP per angle δ_BDP or FDP at angle δ_FDP. Submarine angular movements are sequentially set by angles of attack α, drift β and bank θ at different angles of rudders of rudders δ_SP, δ_UVR, δ_LVR, δ_BDP or δ_FDP. As a result, stationary hydrodynamic effects on underwater object are determined with consideration of rudders at different values of angles of attack α, drift β and bank θ, and analyzed. Positional hydrodynamic characteristics of the underwater facility are determined with account of rudders.

EFFECT: higher safety and accuracy of underwater object control.

1 cl, 8 dwg

Description

The invention relates to the management of ships, in particular, underwater vehicles, is intended to determine the parameters of stability and controllability of an underwater object and can be used to predict the trajectories of underwater vehicles performing complex maneuvering.

There is a known method for determining the positional hydrodynamic characteristics of an underwater object, based on a separate calculated determination of these characteristics for the bare hull of an underwater object and plumage, followed by summing up these characteristics (see Pantov E.N., Makhin N.N., Sheremetov B.B. Fundamentals of the theory movement of underwater vehicles / EN Pantov. - L .: Shipbuilding, 1973. - pp. 59-67).

The disadvantage of this method is only an approximate account of the shape of the body of the underwater object and the influence of rudder shifts, which leads to errors.

Experimental methods for determining the positional hydrodynamic characteristics of an underwater object are also known, based on testing physical models of an underwater object in a water or air environment (see Firsov G.A. Controllability of the ship / G.A. Firsov. - L .: Publishing house of VVMIU named after F. E. Dzerzhinsky, 1954. pp. 60-67). During testing, the flow flows around a fixed physical model of an underwater object. The measurement of the forces and moments acting on the physical model in the flow is carried out using special scales.

The disadvantage of these methods is the presence of errors due to the scale effect, as well as the high cost of producing physical models of the underwater object.

There is also known "Method for determining the damping hydrodynamic characteristics of a ship" (pat.RU No. 2690305, publ. 05/31/2019, IPC: B63N 25/00) - taken as a prototype, including the determination of the center of rotation of the ship, its angular velocity, damping hydrodynamic characteristics of the ship, at the same time, a three-dimensional electronic model of the ship is formed, an internal computational grid in the form of a spherical segment is formed around this three-dimensional electronic model, an internal computational grid in the form of a spherical segment is designed to rotate together with a three-dimensional electronic model relative to the external computational grid. In the computational domain occupied by the inner and outer computational grids, the distribution of the flow velocity and pressure fields is determined, the velocity of fluid movement at the inlet relative to the flow boundary of the computational domain is set equal to the linear velocity of the ship's motion, while the oscillations of the three-dimensional electronic model are set in the drift angle, in As a result, unsteady hydrodynamic effects on a three-dimensional electronic model are determined: the components of the hydrodynamic force and moment in a connected coordinate system, analyze them and determine the values of hydrodynamic effects at drift angles equal to zero, then determine the damping hydrodynamic characteristics of the ship, and the obtained damping hydrodynamic characteristics are used when performing a complex maneuver by ship.

The disadvantage of this method is the inability to determine the positional hydrodynamic characteristics of the ship, as well as not taking into account the influence of rudder shifting, which leads to errors.

The objective of the invention is to improve the safety of control of an underwater object when it performs complex maneuvers by increasing the accuracy of predicting its movement along a given trajectory using computer modeling based on the calculated positional hydrodynamic characteristics of the underwater object, taking into account the rudder shifts, which reduces the error in determining the diameter of the circulation of the underwater object when maneuvering, thereby reducing the likelihood of navigational accidents.

The task is achieved by the fact that the proposed method for determining the positional hydrodynamic characteristics of an underwater object includes determining the center of rotation of an underwater object, forming a three-dimensional electronic model of an underwater object, an internal computational grid is formed around this three-dimensional electronic model, the internal computational grid is rotatable together with a three-dimensional electronic model underwater object relative to the external computational grid. In the computational domain occupied by the internal and external computational grids, the distribution of the flow velocity and pressure fields is determined, the velocity of fluid movement at the inlet relative to the flow boundary of the computational domain is set equal to the linear velocity of the underwater object, while, in contrast to the prototype, the internal computational grid around the three-dimensional The electronic model of an underwater object is formed into a spherical shape, with the center of the sphere coinciding with the point of rotation of the underwater object. Local deformable computational grids are formed around the aft horizontal rudders (KGR), the upper vertical rudder (VVR), the lower vertical rudder (NVR), forward horizontal rudders (NGR) or the cutting horizontal rudders (RGR), with the possibility of shifting the aft horizontal rudders to the angle δ _KGR , upper vertical rudder (VVR) at an angle of δ _VVR , lower vertical rudder (HBP) at an angle of δ _HBR , bow horizontal rudders at an angle of δ _NGR or cutting horizontal rudders at an angle of δ _RGR . The angular displacements of the underwater object are sequentially set along the angles of attack α, drift β and roll θ at different angles of rudder shifting δ _GSR , δ _VVR , δ _NVR , δ _NGR or δ _RGR . As a result, the stationary hydrodynamic effects on the underwater object are determined, taking into account the rudder shifts at different values of the angles of attack α, drift β and roll θ, they are analyzed and then the positional hydrodynamic characteristics of the underwater object are determined according to the ratios:

here

с _х - coefficient of positional hydrodynamic force along the ОХ axis;

F _x - component of the positional hydrodynamic force along the ОХ axis;

m _x - coefficient of positional hydrodynamic moment relative to the OX axis;

M _x - component of the positional hydrodynamic moment relative to the OX axis;

with _y - coefficient of positional hydrodynamic force along the OY axis;

F _y - component of the positional hydrodynamic force along the OY axis;

m _y is the coefficient of the positional hydrodynamic moment relative to the OY axis;

M _y - component of the positional hydrodynamic moment relative to the OY axis;

c _z - coefficient of positional hydrodynamic force along the OZ axis;

F _z - component of the positional hydrodynamic force along the OZ axis;

m _{z is the} coefficient of the positional hydrodynamic moment relative to the OZ axis;

M _z is the component of the positional hydrodynamic moment relative to the OZ axis, then these positional hydrodynamic characteristics are used in computer modeling to predict the movement of an underwater object under complex maneuvering conditions.

The significance of the differences between the proposed method and the prototype is determined as follows. Sequential execution of operations aimed at the formation of an internal spherical computational grid with the center of the sphere coinciding with the point of rotation of the underwater object, with the possibility of rotation together with a three-dimensional electronic model of the underwater object relative to the external computational grid and local deformable computational grids with the possibility of shifting the rudders, allows you to set angular displacements underwater object at angles of attack α, drift β and roll θ in the flow and, thus:

- to improve the accuracy of predicting the movement of an underwater object along a given trajectory using computer modeling based on the calculated positional hydrodynamic characteristics of the underwater object,

- to reduce the error in determining the diameter of the circulation of an underwater object during maneuvering.

Thus, the combination of these essential features allows achieving a new technical result, namely:

to increase the safety of control of an underwater object when performing complex maneuvers;

- to improve the control accuracy of an underwater object.

The essence of the method for determining the positional hydrodynamic characteristics of an underwater object, taking into account the rudder shifts, is illustrated by drawings, where

in fig. 1 is a diagram showing the setting of the angular displacements of an underwater object in terms of the angle of attack;

in fig. 2 is a diagram showing the setting of the angular displacements of the underwater object in terms of the drift angle;

in fig. 3 is a diagram showing the assignment of angular displacements of an underwater object along the roll angle;

in fig. 4 is a diagram showing the shifting of aft horizontal rudders;

in fig. 5 is a diagram showing the transfer of the upper vertical rudder;

in fig. 6 is a diagram showing the transfer of the lower vertical rudder;

in fig. 7 is a diagram showing the transfer of the forward horizontal rudders;

in fig. 8 is a diagram showing the shifting of the cutting horizontal rudders.

To determine the positional hydrodynamic characteristics of the underwater object, an internal spherical computational grid 2 is formed near the three-dimensional electronic model of the underwater object 1 with the center of the sphere coinciding with the point of rotation of the three-dimensional electronic model of the underwater object. The internal spherical computational grid 2 is rotatable together with a three-dimensional electronic model of the underwater object 1 relative to the external computational grid 3. Around the aft horizontal rudders 4, the upper vertical rudder 5, the lower vertical rudder 6, the bow horizontal rudders 7 or the cutting horizontal rudders 8, local deformable computational grids 9, 10, 11, 12, 13, with the possibility of shifting the aft horizontal rudders 4 to the angle δ _GSR , the upper vertical rudder 5 to the angle δ _VVR , the lower vertical rudder 6 to the angle δ _HBR , bow horizontal rudders 7 to the angle δ _NGR or felling horizontal rudders 8 at an angle δ _RGR . In the computational domain formed by internal 2, external 3 and local deformable computational grids 9, 10, 11, 12, 13, the distribution of the flow velocity and pressure fields is determined. The velocity of fluid movement at the inlet with respect to the flow boundary of the computational domain is set equal to the linear velocity of movement of the underwater object. A flow coordinate system is introduced with the origin at the point of rotation of the underwater object (point O). The OX axis is directed parallel to the oncoming flow velocity vector into the bow, OY - upward, OZ - to the starboard side. The angular displacements of the underwater object are sequentially set along the angles of attack α, drift β and roll θ at different angles of rudder shifting δ _GSR , δ _VVR , δ _NVR , δ _NGR or δ _RGR . As a result, the stationary hydrodynamic effects on the underwater object are determined, taking into account the rudder shifts at different values of the angles of attack α, drift β and roll θ, they are analyzed and then the positional hydrodynamic characteristics of the underwater object are determined according to the ratios:

here

с _х - coefficient of positional hydrodynamic force along the ОХ axis;

F _x - component of the positional hydrodynamic force along the ОХ axis;

m _x - coefficient of positional hydrodynamic moment relative to the OX axis;

M _x - component of the positional hydrodynamic moment relative to the OX axis;

with _y - coefficient of positional hydrodynamic force along the OY axis;

F _y - component of the positional hydrodynamic force along the OY axis;

m _y is the coefficient of the positional hydrodynamic moment relative to the OY axis;

Mu is the component of the positional hydrodynamic moment relative to the OY axis;

c _z - coefficient of positional hydrodynamic force along the OZ axis;

F _z - component of the positional hydrodynamic force along the OZ axis;

m _z is the coefficient of the positional hydrodynamic moment relative to the OZ axis;

M _z is the component of the positional hydrodynamic moment relative to the OZ axis.

The obtained positional hydrodynamic characteristics of the underwater object, taking into account the rudder shifting, are used in computer modeling to predict the movement of the underwater object under complex maneuvering conditions.

The applicant conducted studies of the considered technical solution "Method for determining the positional hydrodynamic characteristics of an underwater object", aimed at improving the safety of ship control, where an underwater vehicle with certain hydrodynamic characteristics was selected as the object of modeling.

Analysis of the data obtained showed that the error in determining the diameter of the circulation of an underwater object during maneuvering decreases, thereby reducing the likelihood of navigation accidents.

The control accuracy of the underwater object is increased by taking into account the stationary hydrodynamic effects arising from the angular displacements of the underwater object in the flow, taking into account the rudder shifts.

Thus, the technical result of the invention is to improve the safety of control of the underwater object when performing complex maneuvers, as well as to increase the accuracy of control of the underwater object.

Claims (20)

A method for determining the positional hydrodynamic characteristics of an underwater object, including determining the center of rotation of an underwater object, forming a three-dimensional electronic model of an underwater object, an internal computational grid is formed around this three-dimensional electronic model, the internal computational grid is rotatable together with a three-dimensional electronic model of an underwater object relative to an external computational grid , in the computational domain occupied by the internal and external computational grids, the distribution of the fields of velocities and pressures of the flow is determined, the velocity of fluid movement at the inlet relative to the flow boundary of the computational domain is set equal to the linear velocity of movement of the underwater object, characterized in that the internal computational grid around a three-dimensional electronic the models of the underwater object are spherical in shape with the center of the sphere coinciding with the point of rotation of the underwater object, around the aft horizontal rudders (GSR), the upper vertical rudder (VVR), lower vertical rudder (NVR), bow horizontal rudders (NGR) or cutting horizontal rudders (RGR) form local deformable computational grids with the possibility of shifting aft horizontal rudders by angle δ _KGR , upper vertical rudder (VVR) at an angle δ _VVR , lower vertical rudder (HBR) at an angle δ _HBR , bow horizontal rudders at an angle δ _NGR or cutting horizontal rudders at an angle δ _RGR , sequentially set the angular displacements of the underwater object at angles of attack α, drift β and roll θ at different angles of shifting rudders δ _GSR , δ _VVR , δ _NVR , δ _NGR or δ _RGR , as a result, stationary hydrodynamic effects on the underwater object are determined, taking into account rudder shifts at different values of the angles of attack α, drift β and roll θ, analyze them and then determine the positional hydrodynamic characteristics underwater object according to the ratios:

here с _х - coefficient of positional hydrodynamic force along the ОХ axis; F _x - component of the positional hydrodynamic force along the ОХ axis; m _x - coefficient of positional hydrodynamic moment relative to the OX axis; M _x - component of the positional hydrodynamic moment relative to the OX axis; with _y - coefficient of positional hydrodynamic force along the OY axis; F _y - component of the positional hydrodynamic force along the OY axis; m _y is the coefficient of the positional hydrodynamic moment relative to the OY axis; M _y - component of the positional hydrodynamic moment relative to the OY axis; c _z - coefficient of positional hydrodynamic force along the OZ axis; F _z - component of the positional hydrodynamic force along the OZ axis; m _z is the coefficient of the positional hydrodynamic moment relative to the OZ axis; M _z is the component of the positional hydrodynamic moment relative to the OZ axis, then these positional hydrodynamic characteristics are used when performing a complex maneuver by an underwater object.

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