CN112224359B - Ship power distribution method capable of being used in different navigational speed modes - Google Patents

Ship power distribution method capable of being used in different navigational speed modes Download PDF

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CN112224359B
CN112224359B CN202010776712.8A CN202010776712A CN112224359B CN 112224359 B CN112224359 B CN 112224359B CN 202010776712 A CN202010776712 A CN 202010776712A CN 112224359 B CN112224359 B CN 112224359B
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ship
rudder
thrust
propeller
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王晓原
夏媛媛
姜雨函
朱慎超
曹志伟
王曼曼
高杰
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Navigation Brilliance Qingdao Technology Co Ltd
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    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B63—SHIPS OR OTHER WATERBORNE VESSELS; RELATED EQUIPMENT
    • B63B—SHIPS OR OTHER WATERBORNE VESSELS; EQUIPMENT FOR SHIPPING 
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Abstract

The invention relates to a ship thrust distribution method capable of being used in different navigational speed modes, which comprises the following steps: (1) establishing a thrust calculation mathematical model of various thrusters of the ship; (2) establishing a rudder force calculation mathematical model of the ship; (3) establishing a ship stress model based on various propeller thrust calculation mathematical models and rudder force calculation mathematical models of the ship; (4) optimally establishing an optimization objective function based on the power consumption and the distribution effect of various propellers, and establishing corresponding constraint conditions based on the mechanical properties of various propellers and a ship stress model; (5) and solving the optimized objective function by using an optimization algorithm to obtain the actual thrust value of each thruster. The thrust distribution optimization problem under the low-speed and medium-high speed modes can be realized by utilizing the combination of double propellers, double rudders and lateral thrusters.

Description

Ship power distribution method capable of being used in different navigational speed modes
Technical Field
The invention belongs to the technical field of ship thrust distribution, relates to a ship thrust distribution method, and particularly relates to a ship power distribution method capable of being used in different navigational speed modes.
Background
With the emergence of ships with different purposes and the increasing number of ships, the position control capability of the ships in navigation becomes more and more important. The ship with the good dynamic positioning technology can not only efficiently complete various tasks, but also ensure that the ship is in a safe environment at any time. With the continuous progress of science and technology, the dynamic positioning technology of ships becomes more and more advanced.
In the dynamic positioning technology, a thrust distribution system is an important component in the technology, and is used for distributing command acting force and moment obtained by calculation of a control system to each propeller, and the ship can meet the dynamic positioning requirement with the least energy consumption through the cooperation of the propellers.
At the present stage, due to the limitation of ship types and purposes, most of research is based on a thrust distribution optimization strategy of a full-rotation propeller and a lateral propeller, and the optimization research on the thrust distribution method of the ship with a paddle-rudder combination and the lateral propeller is less. In the existing research, thrust distribution under medium and high speed is realized only by using the condition that a propeller is used for driving, and thrust distribution in the low-speed process is not realized.
In view of the above technical defects in the prior art, it is urgently needed to develop a ship power distribution method which can be used in different navigational speed modes.
Disclosure of Invention
In order to solve the defects and shortcomings of the problems, the invention provides a ship thrust distribution method capable of being used in different navigational speed modes, which can realize the thrust distribution optimization problem in low-speed and medium-high speed modes by using the combination of double-oar and double-rudder plus a lateral thruster.
In order to achieve the above purpose, the invention provides the following technical scheme:
a ship thrust distribution method capable of being used in different navigational speed modes is characterized by comprising the following steps:
(1) establishing a thrust calculation mathematical model of various thrusters of the ship;
(2) establishing a rudder force calculation mathematical model of the ship;
(3) establishing a ship stress model based on thrust calculation mathematical models and rudder calculation mathematical models of various propellers of a ship;
(4) optimally establishing an optimization objective function based on the power consumption and the distribution effect of various propellers, and establishing corresponding constraint conditions based on the mechanical properties of various propellers and a ship stress model;
(5) and solving the optimized objective function by using an optimization algorithm to obtain the actual thrust value of each thruster.
Preferably, in the step (3), a ship stress model at a medium-high speed, that is, at a ship speed of more than 3kn, and a ship stress model at a low speed, that is, at a ship speed of less than or equal to 3kn, are established based on a thrust calculation mathematical model and a rudder force calculation mathematical model of various propellers of the ship, respectively.
Preferably, the establishing of the thrust force calculation mathematical model of the various thrusters of the ship in the step (1) specifically includes:
(1.1) establishing a thrust calculation mathematical model of the main thrust propeller, wherein,
when driving, Tm＝(1-tp)·KT(J)ρnm 2D4
When backing, Tm＝-0.75(1-tp)·KT(J)ρnm 2D4
In the formula, TmThrust for the m-th main propeller, tpIs the thrust derating fraction, KT(J) Is the thrust coefficient, J is the advance coefficient, rho is the seawater density, nmThe rotating speed of the mth main pushing propeller is shown, and D is the diameter of the main pushing propeller;
wherein the thrust derating fraction tpEstimated using the holter lop formula:
Figure GDA0003311882510000021
in the formula, CBThe square coefficient of the ship is shown, D is the diameter of a main pushing propeller, B is the width of the ship, and T is the draught depth;
(1.2) establishing a thrust calculation mathematical model of the lateral thruster, wherein,
when the rotating shaft rotates forwards,
Figure GDA0003311882510000022
when the rotation is carried out in the reverse direction,
Figure GDA0003311882510000031
Tfexpressing the thrust of the f-th lateral thruster, a is a fitting coefficient, nfThe rotational speed of the f-th lateral thruster.
Preferably, the step (2) of establishing a rudder force calculation mathematical model of the ship specifically includes:
Figure GDA0003311882510000032
in the formula, Tx,iIs the component force of the steering force of the ith rudder in the ship length direction,
Ty,iis the component force of the steering force of the ith rudder in the width direction of the ship,
Niis a rotation moment formed by the rudder force component of the ith rudder along the width direction of the ship around the rotation center of the ship,
t' is a rudder resistance derating coefficient, and the calculation formula is as follows:
Figure GDA0003311882510000033
FN,ithe normal force of the ith rudder is the positive pressure of the ith rudder,
Figure GDA0003311882510000034
CN,icalculating the normal force coefficient of the ith rudder by using a rattan well formula to obtain:
Figure GDA0003311882510000035
lambda is the flare-to-side ratio of the rudder,
Uithe incoming flow velocity of the leading edge of the rudder blade of the ith rudder, AiThe rudder blade area of the ith rudder,
αiis the effective angle of attack, δ, of the ith rudderiIs the ithA rudder angle of the rudder;
k1representing the influence of the hull on the incoming flow velocity of the rudder,
k1＝(1-ωR)2
Figure GDA0003311882510000036
in the formula,. DELTA.omegaRThe influence of the shape of the stern on the wake fraction of the rudder blade,
Figure GDA0003311882510000041
w is the influence of the arrangement position of the rudder on the wake fraction of the rudder blade
Figure GDA0003311882510000042
h1The distance between the lower edge of the rudder blade and the baseline of the ship body,
h2the height of the rudder is set as the height of the rudder,
h is the distance between the hull base line and the intersection point of the rudder stock central line and the hull,
k2representing the influence of the wake of the main propeller on the incoming flow speed of the rudder, k2＝1，
k3Representing the influence of the presence or absence of a rudder post on the incoming flow velocity of the rudder, k without a rudder post3＝1，
αHThe calculation formula of the correction factor of the lateral force of the ship body induced by steering is as follows:
Figure GDA0003311882510000043
xHthe calculation formula of the distance from the steering induced hull transverse force action center to the ship gravity center is as follows:
xH＝-L(0.4+0.1CB)
wherein L is the length of the ship,
x2the longitudinal distance between the rotation center of the rudder blade and the center of gravity of the ship.
Preferably, wherein, established in the step (3)
The ship stress model at medium and high speed is
Figure GDA0003311882510000044
In the formula, ymThe distance from the rotation center of the mth main propulsion propeller to the center line of the ship body, yiThe distance between the rotation center of the ith rudder blade and the center line of the ship body is tauxThe expected thrust of all the propellers on the ship along the ship length direction; tau isyThe expected thrust of all the thrusters on the ship along the width direction of the ship; mzThe expected moment of all the thrusters on the ship along the heave direction, and M is the number of main push propellers of the ship;
the ship stress model at low speed is
Figure GDA0003311882510000051
In the formula, xfThe longitudinal distance from the F-th lateral thruster to the center of gravity of the ship is defined, and F is the number of the lateral thrusters of the ship.
Preferably, wherein, established in the step (4)
The optimization objective function is:
Figure GDA0003311882510000052
wherein M is the total number of main propeller on the ship, F is the total number of lateral propeller on the ship, sxFor thrust distribution errors in the direction of the length of the ship, syFor thrust distribution errors in the width direction of the ship, szFor distributing errors in moment about the centre of rotation of the vessel, w1…w5Is the weight;
(a) the equation is constrained as:
in the medium-high speed mode:
Figure GDA0003311882510000053
in the low-speed mode:
Figure GDA0003311882510000061
(b) the inequality constraint is:
rudder angle constraint
δmin≤δ≤δmax
δmax＝min(δ0+Δδ,δ′max)
δmin＝max(δ0-Δδ,δ′min)
δ′max，δ′minThe maximum rudder angle and the minimum rudder angle which can be realized by the rudder;
delta is the variable quantity of the rudder angle in a single operation period;
δ0the current rudder angle of the ship;
thrust restraint:
Tmin≤Tm≤Tmax
Tmin≤Tf≤Tmax
Tmax＝min(T0+ΔT,T′max)
Tmin＝max(T0-ΔT,T′min)
Tfeither as 0 (in high speed mode)
T′max，T′minMaximum and minimum thrusts that can be achieved for each thruster;
delta T is the variable quantity of thrust in a single operation period of each thruster;
T0the current thrust value of the ship.
Preferably, in the step (5), a genetic algorithm in a modern optimization theory is used as an optimization algorithm to solve the optimization objective function, so as to obtain an actual thrust value of each propeller.
Compared with the prior art, the ship power distribution method capable of being used in different navigational speed modes has the following beneficial technical effects:
1. based on different navigational speeds, different modes of medium-high speed thrust distribution and low-speed thrust distribution are respectively designed, and the continuity of thrust distribution in the ship motion process can be ensured.
2. The function of the propeller is fully adopted in the low-speed thrust distribution mode, the thrust distribution is realized by utilizing the combined action of the forward and reverse rotation of the main thrust propeller and the lateral thruster, and the optimal solution is obtained by comparing the energy consumption and the error of the double propellers in four modes formed in different states.
3. The optimization method for full-speed-domain thrust distribution is provided for the existing double-paddle and double-rudder ship, the dynamic positioning transformation technology of the existing ship is greatly facilitated, the ship transformation time can be greatly saved, and the transformation cost is saved.
4. The combination of the low-speed mode and the medium-high speed mode can more specifically consider the first factors required under different modes, and the requirements of high precision and low energy consumption during low-speed navigation and medium-high speed navigation are considered, so that the actual effect of dynamic positioning is optimized.
Drawings
Fig. 1 is a flow chart of the thrust allocation method of a ship, which can be used in different navigational modes, according to the present invention.
Fig. 2 is a schematic diagram of an exemplary marine propulsor arrangement.
Detailed Description
The present invention is further illustrated by the following examples, which are not intended to limit the scope of the present invention.
The invention relates to a ship thrust distribution method capable of being used in different navigational speed modes, which can realize ship power distribution in a low-speed mode and a medium-high speed mode.
Fig. 1 shows a flow chart of the thrust distribution method of a ship of the present invention, which can be used in different navigational modes. As shown in fig. 1, the method for distributing the thrust of the ship, which can be used in different navigational speed modes, of the present invention comprises the following steps:
firstly, a thrust calculation mathematical model of various propellers of a ship is established.
Consider a propeller for a ship that has both a main propulsion propeller and a side propulsion propeller. Therefore, in the invention, corresponding thrust calculation mathematical models are required to be established for the main thrust propeller and the lateral thruster respectively.
1. And establishing a thrust calculation mathematical model of the main thrust propeller.
Since the lateral force of the main propulsion propeller is a minimum value compared to the longitudinal force and does not affect the ship motion, the lateral force is generally ignored in the calculation. Therefore, only the longitudinal forces generated by the main thrust propeller are considered here, and the transverse forces generated by the main thrust propeller are not considered. And, the thrust calculation mathematical model when driving and backing is considered separately. Wherein the content of the first and second substances,
when driving, Tm＝(1-tp)·KT(J)ρnm 2D4
When backing, Tm＝-0.75(1-tp)·KT(J)ρnm 2D4。
In the formula, TmThrust for the m-th main propeller, tpIs the thrust derating fraction, KT(J) Is the thrust coefficient, J is the advance coefficient, rho is the seawater density, nmThe rotating speed of the mth main propeller is shown, and D is the diameter of the main propeller.
Wherein, the thrust coefficient K of the main propellerT(J) The size of the speed coefficient is in functional relation with the speed coefficient J, the size of the speed coefficient is determined according to the current ship state,
Figure GDA0003311882510000081
wherein, ω ispIs the wake fraction of the main thrust propeller,
ωp＝0.55CB-0.2
v is the ship speed, n is the rotating speed of the main pushing propeller, and D is the diameter of the main pushing propeller. Of course, in the specific calculation, the open water characteristic curve of the propeller can be searched according to the speed coefficient, and the size of the speed coefficient is obtained.
Wherein the thrust derating fraction tpEstimated using the holter lop formula:
Figure GDA0003311882510000082
in the formula, CBThe coefficient is the square coefficient of the ship, D is the diameter of the main pushing propeller, B is the width of the ship, and T is the draft.
2. And establishing a thrust calculation mathematical model of the lateral thruster.
The lateral thrusters have a differential between forward and reverse rotation and therefore should be set up separately when building the thrust mathematical model. Wherein the content of the first and second substances,
when the rotating shaft rotates forwards,
Figure GDA0003311882510000091
when the rotation is carried out in the reverse direction,
Figure GDA0003311882510000092
in the formula, TfExpressing the thrust of the f-th lateral thruster, a is a fitting coefficient which is obtained by fitting the thrust-rotating speed curve of the lateral thruster, nfThe rotational speed of the f-th lateral thruster.
And secondly, establishing a rudder force calculation mathematical model of the ship.
The ship has two steering engines, namely a left steering engine and a right steering engine, so that the left and right points are considered when a ship rudder force calculation mathematical model is established. The method comprises the following steps of establishing a rudder force calculation mathematical model of a ship:
Figure GDA0003311882510000093
in the formula，Tx,iIs the component force of the steering force of the ith rudder in the ship length direction,
Ty,iis the component force of the steering force of the ith rudder in the width direction of the ship,
Niis a rotation moment formed by the rudder force component of the ith rudder along the width direction of the ship around the rotation center of the ship,
t' is a rudder resistance derating coefficient, and the calculation formula is as follows:
Figure GDA0003311882510000094
FN,ithe normal force of the ith rudder is the positive pressure of the ith rudder,
Figure GDA0003311882510000095
CN,icalculating the normal force coefficient of the ith rudder by using a rattan well formula to obtain:
Figure GDA0003311882510000096
lambda is the spanwise ratio of the rudder,
Uithe incoming flow velocity of the leading edge of the rudder blade of the ith rudder, AiThe rudder blade area of the ith rudder,
αifor the effective angle of attack of the ith rudder, the approximation is taken as: alpha is alphai＝δi，δiThe rudder angle of the ith rudder;
k1representing the influence of the hull on the incoming flow velocity of the rudder,
k1＝(1-ωR)2
Figure GDA0003311882510000101
in the formula,. DELTA.omegaRThe influence of the shape of the stern on the wake fraction of the rudder blade,
Figure GDA0003311882510000102
w is the influence of the arrangement position of the rudder on the wake fraction of the rudder blade
Figure GDA0003311882510000103
h1The distance between the lower edge of the rudder blade and the baseline of the ship body,
h2the height of the rudder is set as the height of the rudder,
h is the distance between the hull base line and the intersection point of the rudder stock central line and the hull,
k2representing the influence of the wake of the main propeller on the incoming flow speed of the rudder, k2＝1，
k3Representing the influence of the existence of a rudder post on the incoming flow speed of a rudder, in the invention, the ship is a ship without the rudder post, and k is used when the rudder post is absent3＝1，
αHThe calculation formula of the correction factor of the lateral force of the ship body induced by steering is as follows:
Figure GDA0003311882510000104
xHthe calculation formula of the distance from the steering induced hull transverse force action center to the ship gravity center is as follows:
xH＝-L(0.4+0.1CB)
wherein L is the captain of the ship
x2The longitudinal distance between the rotation center of the rudder blade and the center of gravity of the ship.
And thirdly, establishing a ship stress model based on thrust calculation mathematical models and rudder calculation mathematical models of various propellers of the ship.
In the invention, a ship stress model is established at medium and high speed, namely when the ship speed is more than 3kn, and at low speed, namely when the ship speed is less than or equal to 3kn, respectively based on a thrust calculation mathematical model and a rudder force calculation mathematical model of various propellers of the ship. Wherein kn is the ship speed unit, and 1kn is 1.852 km/h. In particular, the amount of the solvent to be used,
the ship stress model at medium and high speed is
Figure GDA0003311882510000111
In the formula, ymThe distance from the rotation center of the mth main propulsion propeller to the center line of the ship body, yiThe distance between the rotation center of the ith rudder blade and the center line of the ship body is tauxThe expected thrust of all the propellers (including a main thrust propeller and a side thruster) on the ship along the length direction of the ship; tau isyThe expected thrust of all the propellers on the ship in the width direction of the ship; mzThe expected moment of all the thrusters on the ship along the heave direction, and M is the number of main push propellers of the ship.
The ship stress model at low speed is
Figure GDA0003311882510000112
In the formula, xfThe longitudinal distance from the F-th lateral thruster to the center of gravity of the ship is defined, and F is the number of the lateral thrusters on the ship.
And fourthly, optimally establishing an optimization objective function based on the power consumption and the distribution effect of various propellers, and establishing corresponding constraint conditions based on the mechanical properties of various propellers and a ship stress model.
In the invention, the established optimization objective function is as follows:
Figure GDA0003311882510000113
wherein M is the total number of main propeller on the ship, F is the total number of lateral propeller on the ship, sxFor thrust distribution errors in the direction of the length of the ship, syFor thrust distribution errors in the width direction of the ship, szFor moment about the centre of rotation of the vesselError of fit, w1…w5Is a weight, wherein, w1…w4Initial value of 1, w5The initial value is 1, and the specific value can be corrected and determined according to the actual performance of the ship and the actual ship test result of the ship;
(a) the equation is constrained as:
in the high-speed mode:
Figure GDA0003311882510000121
in the low-speed mode:
Figure GDA0003311882510000122
(b) the inequality constraint is:
rudder angle constraint
δmin≤δ≤δmax
δmax＝min(δ0+Δδ,δ′max)
δmin＝max(δ0-Δδ,δ′min)
δ′max，δ′minThe maximum rudder angle and the minimum rudder angle which can be realized by the rudder;
delta is the variable quantity of the rudder angle in a single operation period;
δ0the current rudder angle of the ship;
thrust restraint:
Tmin≤Tm≤Tmax
Tmin≤Tf≤Tmax
Tmax＝min(T0+ΔT,T′max)
Tmin＝max(T0-ΔT,T′min)
Tfeither as 0 (in high speed mode)
T′max，T′minMaximum thrust achievable for each propellerAnd a minimum thrust;
delta T is the variable quantity of thrust in a single operation period of each thruster;
T0the current thrust value of the ship.
And fifthly, solving the optimized objective function by using an optimization algorithm to obtain the actual thrust value of each thruster.
Preferably, the genetic algorithm in the modern optimization theory can be used as an optimization algorithm to solve the optimization objective function to obtain the actual thrust value of each propeller.
The following takes the stressed ship of fig. 2 as an example to describe a specific application of the ship thrust distribution method of the present invention that can be used in different navigational speed modes.
The ship has the advantages that during middle-high speed (namely, the ship speed is higher than 3kn) navigation, transverse force generated by side thrust hardly plays a role in ship movement, and during middle-high speed navigation, due to the fact that the ship inertia is large, the requirement on positioning accuracy during navigation is relatively loose, and therefore when high-speed thrust distribution is performed, a double-propeller and double-rudder (namely, a lateral propeller is not adopted, namely, the thrust of the lateral propeller is zero) + the forward mode is adopted to achieve a corresponding thrust distribution optimization task.
Firstly, establishing a ship stress model according to a propeller layout:
Figure GDA0003311882510000131
wherein: t is1Thrust generated by a No. 1 main thrust propeller;
T2thrust generated by a No. 2 main thrust propeller;
Tx,leftforces acting on the left rudder in the x direction, i.e. the longitudinal direction of the ship, NleftA force acting on the left rudder in the y direction, i.e., the ship width direction;
Tx,rightforces acting in the x-direction, i.e. the longitudinal direction of the ship, N, for the right rudderrightA force acting on the right rudder in the y direction, i.e., the ship width direction;
y1the distance between the rotation center of the main pushing propeller and the center line of the ship body; y is2The distance between the rotation center of the rudder blade and the center line of the ship body is shown;
τxfor the desired force to be achieved in the direction of the length of the vessel, τyFor the desired force to be achieved in the width direction of the ship, MzThe desired moment to be achieved about the centre of rotation of the vessel.
The force model is rewritten to a matrix form:
Figure GDA0003311882510000141
coefficient matrix:
Figure GDA0003311882510000142
x2the longitudinal distance from the rotation center of the rudder blade to the gravity center of the ship;
the optimization objective function is:
Figure GDA0003311882510000143
wherein: the first term and the second term are thrust and normal force generated by the propeller and the rudder respectively, the third term, the fourth term and the fifth term are errors of actual thrust and expected thrust, and w is1…w5Is a weight value.
(1) And (3) constraint of an equation:
Figure GDA0003311882510000144
T1thrust generated by a No. 1 main thrust propeller;
T2thrust generated by a No. 2 main thrust propeller;
sxfor thrust distribution error in the x-direction, sxFor thrust distribution error in the y-direction, szTo rotate inThe moment distribution error of the core is determined,
(2) inequality constraint
Rudder angle constraint
δmin≤δ≤δmax
δmax＝min(δ0+Δδ,δ′max)
δmin＝max(δ0-Δδ,δ′min)
δ′max，δ′minThe maximum rudder angle and the minimum rudder angle which can be realized by the rudder.
Delta is the variable quantity of the rudder angle in a single operation period;
δ0the current rudder angle of the ship;
thrust restraint:
Tmin≤Ti≤Tmax
Tmax＝min(T0+ΔT,T′max)
Tmin＝max(T0-ΔT,T′min)
T′max，T′minthe maximum thrust and the minimum thrust that can be achieved by the propeller.
Δ T is the variable amount of thrust within a single operating cycle;
T0the current thrust value of the ship is obtained;
after the thrust distribution mathematical model is established, the thrust distribution model is solved by using a genetic algorithm in a modern optimization theory as an optimization algorithm to obtain the actual thrust value of each propeller.
When the high-speed sailing vehicle is in low-speed sailing, the main engine is divided into two modes, namely a forward sailing mode and a reverse sailing mode, for the fixed pitch propeller, the thrust calculation in the two modes is different, when the reverse sailing mode is considered, in order to reduce power consumption, the reverse sailing mode is only used as a braking means, and reverse sailing is not adopted. Therefore, the modes of the two main machines are combined into 4 combinations (the maximum value of the thrust generated by the side-pushing forward and reverse directions is the same).
Figure GDA0003311882510000161
And respectively solving the component force of each propeller in the four combinations, comprehensively comparing the optimization results of the four combinations, and taking the minimum objective function value as the optimization result.
Ship stress model:
Figure GDA0003311882510000162
x3the longitudinal distance from the No. 3 lateral thruster to the gravity center of the ship;
x4the longitudinal distance from the No. 4 lateral thruster to the gravity center of the ship;
the ship stress model is rewritten into a matrix form:
Figure GDA0003311882510000163
coefficient matrix:
Figure GDA0003311882510000164
the optimization objective function is:
Figure GDA0003311882510000165
wherein: the first term and the second term are thrust and normal force generated by the propeller and the rudder respectively, the third term, the fourth term and the fifth term are errors of actual thrust and expected thrust, and w is1…w5Is a weight value.
(1) And (3) constraint of an equation:
Figure GDA0003311882510000171
T1is No. 1 main push propellerThe thrust generated;
T2thrust generated by a No. 2 main thrust propeller;
T3thrust generated by the No. 3 lateral thruster;
T4thrust generated by a No. 4 lateral thruster;
sxfor thrust distribution error in the x-direction, syFor thrust distribution error in the y-direction, szAn error is distributed to the moment about the center of rotation,
(2) constraint of inequality
Rudder angle constraint
δmin≤δ≤δmax
δmax＝min(δ0+Δδ,δ′max)
δmin＝max(δ0-Δδ,δ′min)
δ′max，δ′minThe maximum rudder angle and the minimum rudder angle which can be realized by the rudder.
Delta is the variable quantity of the rudder angle in a single operation period;
δ0the current rudder angle of the ship;
thrust restraint:
Tmin≤Ti≤Tmax
Tmax＝min(T0+ΔT,T′max)
Tmin＝max(T0-ΔT,T′min)
T3＝T4either as 0 (in high speed mode)
T′max，T′minThe maximum thrust and the minimum thrust that can be achieved by the propeller.
Δ T is the variable amount of thrust within a single operating cycle;
T0the current thrust value of the ship.
After the thrust distribution mathematical model is established, the thrust distribution model is solved by using a genetic algorithm in a modern optimization theory as an optimization algorithm to obtain the actual thrust value of each propeller.
The invention provides an optimization method for full-speed domain thrust distribution for the existing double-oar and double-rudder ship, greatly facilitates the dynamic positioning modification technology of the existing ship, and can greatly save the ship modification time and the modification cost. Meanwhile, the combination of the low-speed mode and the medium-high speed mode can more specifically consider the first factors required under different modes, and the requirements of high precision required during low-speed navigation and low energy consumption required during high-speed navigation are taken into consideration, so that the actual effect of dynamic positioning is optimized. The above examples of the present invention are merely examples for clearly illustrating the present invention and are not intended to limit the embodiments of the present invention. Other variations and modifications will be apparent to persons skilled in the art in light of the above description. Not all embodiments are exhaustive. All obvious changes and modifications which are obvious to the technical scheme of the invention are covered by the protection scope of the invention.

Claims (5)

1. A ship thrust distribution method capable of being used in different navigational speed modes is characterized by comprising the following steps:
(1) establishing a thrust calculation mathematical model of various propellers of the ship;
(2) establishing a rudder force calculation mathematical model of the ship;
(3) establishing a ship stress model based on thrust calculation mathematical models and rudder force calculation mathematical models of various propellers of a ship;
(4) optimally establishing an optimization objective function based on the power consumption and the distribution effect of various propellers, and establishing corresponding constraint conditions based on the mechanical properties of various propellers and a ship stress model;
(5) solving the optimized objective function by using an optimization algorithm to obtain the actual thrust value of each thruster;
in the step (3), a ship stress model at a medium and high speed and a ship stress model at a low speed are established respectively based on a thrust calculation mathematical model and a rudder force calculation mathematical model of various propellers of a ship, wherein the medium and high speed is that the ship speed is greater than 3kn, and the low speed is that the ship speed is less than or equal to 3 kn;
the establishing of the thrust calculation mathematical model of the various thrusters of the ship in the step (1) specifically comprises the following steps:
(1.1) establishing a thrust calculation mathematical model of the main thrust propeller, wherein,
when driving, Tm＝(1-tp)·KT(J)ρnm 2D4
When backing, Tm＝-0.75(1-tp)·KT(J)ρnm 2D4
In the formula, TmThrust for the m-th main propeller, tpIs the thrust derating fraction, KT(J) Is the thrust coefficient, J is the advance coefficient, rho is the seawater density, nmThe rotating speed of the mth main pushing propeller is shown, and D is the diameter of the main pushing propeller;
wherein the thrust derating fraction tpEstimated using the holter lop formula:
Figure FDA0003464092780000011
in the formula, CBThe square coefficient of the ship is shown, D is the diameter of a main pushing propeller, B is the width of the ship, and T is the draught depth;
(1.2) establishing a thrust calculation mathematical model of the lateral thruster, wherein,
when the glass is rotated forward,
Figure FDA0003464092780000021
when the rotation is carried out in the reverse direction,
Figure FDA0003464092780000022
Tfexpressing the thrust of the f-th lateral thruster, a is a fitting coefficient, nfThe rotational speed of the f-th lateral thruster.
2. The method for distributing the thrust of the ship capable of being used in different navigational speed modes according to claim 1, wherein the mathematical model for calculating the rudder force of the ship established in the step (2) is specifically:
Figure FDA0003464092780000023
in the formula, Tx,iIs the component force of the steering force of the ith rudder in the ship length direction,
Ty,iis the component force of the steering force of the ith rudder in the width direction of the ship,
Niis a rotation moment formed by the rudder force component of the ith rudder along the width direction of the ship around the rotation center of the ship,
t' is a rudder resistance derating coefficient, and the calculation formula is as follows:
Figure FDA0003464092780000024
FN,ithe normal force of the ith rudder is the positive pressure of the ith rudder,
Figure FDA0003464092780000025
CN,icalculating the normal force coefficient of the ith rudder by using a rattan well formula to obtain:
Figure FDA0003464092780000026
lambda is the spanwise ratio of the rudder,
Uithe incoming flow velocity of the leading edge of the rudder blade of the ith rudder, AiThe rudder blade area of the ith rudder,
αiis the effective angle of attack, δ, of the ith rudderiThe rudder angle of the ith rudder;
k1representing the vessel rudderThe influence of the speed of the incoming flow,
k1＝(1-ωR)2
Figure FDA0003464092780000027
in the formula,. DELTA.omegaRThe influence of the shape of the stern on the wake fraction of the rudder blade,
Figure FDA0003464092780000031
w is the influence of the arrangement position of the rudder on the wake fraction of the rudder blade
Figure FDA0003464092780000032
h1The distance between the lower edge of the rudder blade and the baseline of the ship body,
h2the height of the rudder is set as the height of the rudder,
h is the distance between the hull base line and the intersection point of the rudder stock central line and the hull,
k2representing the influence of the wake of the main propeller on the incoming flow speed of the rudder, k2＝1，
k3Representing the influence of the presence or absence of a rudder post on the incoming flow velocity of the rudder, k without a rudder post3＝1，
αHThe calculation formula of the correction factor of the lateral force of the ship body induced by steering is as follows:
Figure FDA0003464092780000033
xHthe calculation formula of the distance from the steering induced hull transverse force action center to the ship gravity center is as follows:
xH＝-L(0.4+0.1CB)
wherein L is the length of the ship,
x2the centre of rotation of the rudder blade being spaced from the centre of gravity of the vesselA longitudinal distance.
3. Method for distributing the thrust of a ship applicable to different navigational modes according to claim 2, wherein said step (3) is carried out by establishing
The ship stress model at medium and high speed is
Figure FDA0003464092780000034
In the formula, ymThe distance from the rotation center of the mth main propulsion propeller to the center line of the ship body, yiThe distance between the rotation center of the ith rudder blade and the center line of the ship body is tauxThe expected thrust of all the propellers on the ship along the ship length direction; tau isyThe expected thrust of all the propellers on the ship in the width direction of the ship; mzThe expected moment of all the propellers on the ship along the heave direction, and M is the number of main push propellers of the ship;
the ship stress model at low speed is
Figure FDA0003464092780000041
In the formula, xfThe longitudinal distance from the F-th lateral thruster to the center of gravity of the ship is defined, and F is the number of the lateral thrusters of the ship.
4. Method according to claim 3, characterized in that said thrust distribution method of a ship that can be used in different navigational modes is established in said step (4)
The optimization objective function is:
Figure FDA0003464092780000042
wherein M is the total number of main propeller on the ship, F is the total number of lateral propeller on the ship, sxIn the direction of the length of the shipThrust distribution error, syError distribution for thrust in the width direction of the vessel, szFor thrust distribution error about the centre of rotation of the vessel, w1…w5Is the weight;
(a) the equation is constrained as:
in the medium-high speed mode:
Figure FDA0003464092780000043
in the low-speed mode:
Figure FDA0003464092780000051
(b) the inequality constraint is:
rudder angle constraint
δmin≤δ≤δmax
δmax＝min(δ0+Δδ,δ′max)
δmin＝max(δ0-Δδ,δ′min)
δ′max，δ′minThe maximum rudder angle and the minimum rudder angle which can be realized by the rudder;
delta is the variable quantity of the rudder angle in a single operation period;
δ0the current rudder angle of the ship;
thrust restraint:
Tmin≤Tm≤Tmax
Tmin≤Tf≤Tmax
Tmax＝min(T0+ΔT,T′max)
Tmin＝max(T0-ΔT,T′min)
Tf0, in high speed mode;
T′max，T′minmaximum thrust and minimum thrust that can be achieved for each propeller;
delta T is the variable quantity of thrust in a single operation period of each thruster;
T0the current thrust value of the ship.
5. The method according to claim 4, wherein in the step (5), the optimization objective function is solved by using a genetic algorithm in modern optimization theory as an optimization algorithm to obtain the actual thrust value of each thruster.
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Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN107301267A (en) * 2017-05-17 2017-10-27 哈尔滨工程大学 A kind of reduction UUV based on NSGA II algorithms is empty the optimization method of rate
CN108572550A (en) * 2018-03-16 2018-09-25 上海交通大学 A kind of online real-time thrust distribution method based on machine learning
CN108594651A (en) * 2018-03-16 2018-09-28 上海交通大学 A kind of dynamic positioning of vessels thrust distribution intelligent optimization method
CN109343353A (en) * 2018-12-17 2019-02-15 珠海萨博思海洋工程有限公司 A kind of intelligent optimization method for the distribution of dynamic positioning ship thrust
CN109683472A (en) * 2018-08-30 2019-04-26 上海海事大学 A kind of watercraft electric propulsion system thrust distribution method based on Model Predictive Control
CN109799826A (en) * 2019-02-20 2019-05-24 上海振华重工(集团)股份有限公司 The thrust distribution method of marine propulsion systems
CN111061285A (en) * 2019-12-12 2020-04-24 哈尔滨工程大学 Ship dynamic positioning thrust distribution method

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN107301267A (en) * 2017-05-17 2017-10-27 哈尔滨工程大学 A kind of reduction UUV based on NSGA II algorithms is empty the optimization method of rate
CN108572550A (en) * 2018-03-16 2018-09-25 上海交通大学 A kind of online real-time thrust distribution method based on machine learning
CN108594651A (en) * 2018-03-16 2018-09-28 上海交通大学 A kind of dynamic positioning of vessels thrust distribution intelligent optimization method
CN109683472A (en) * 2018-08-30 2019-04-26 上海海事大学 A kind of watercraft electric propulsion system thrust distribution method based on Model Predictive Control
CN109343353A (en) * 2018-12-17 2019-02-15 珠海萨博思海洋工程有限公司 A kind of intelligent optimization method for the distribution of dynamic positioning ship thrust
CN109799826A (en) * 2019-02-20 2019-05-24 上海振华重工(集团)股份有限公司 The thrust distribution method of marine propulsion systems
CN111061285A (en) * 2019-12-12 2020-04-24 哈尔滨工程大学 Ship dynamic positioning thrust distribution method

Non-Patent Citations (3)

* Cited by examiner, † Cited by third party
Title
无人艇的双桨双舵推力优化分配仿真;刘梦佳等;《造船技术》;20180228(第341期);正文第1-7页 *
神经网络船舶航向控制的研究;朱武亭;《工程科技Ⅱ辑》;20070228;C036-35 *
船舶动力定位的智能控制及推力分配研究;刘洋;《工程科技Ⅱ辑》;20140531;C036-10 *

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