CN110020459A - Based on Dynamic mesh ship with wave the motion simulation method on course-and-bearing - Google Patents
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Abstract
The invention discloses one kind based on Dynamic mesh ship with wave the motion simulation method on course-and-bearing, comprising: using the governing equation of CFD, establish turbulence model, establish Simulation Strategy that VOF model, the computation model navigated by water in channel flow using Dynamic mesh, ship, ship are navigated by water in channel flow.The present invention obtains the time history image on corrugated by simulation channel flow second order Stoke wave, realize the generation of wave, propagation, deformation, wave absorption process.
Description
Technical field
The present invention relates to one kind based on Dynamic mesh ship with wave the motion simulation method on course-and-bearing.
Background technique
With the development of ocean engineering, shipping work gradually moves towards deep-sea by coastal waters, and people propose the security performance of ship
Increasingly higher demands out.Ship at sea when driving, will receive the disturbance of the factors such as sea wind, wave, ocean current, will occur each
Kind oscillating motion.In these disturbing factors, wave is the main reason for causing ship rocking movement.Therefore, wave pair is studied
The disturbance of attitude of ship attracts people's attention.
The research that wave disturbs hull, has some scholars to carry out academic research to this very early, and main method has the side CFD
Method and experimental method.CFD approach is shown by computer numerical value calculation and image, to including fluid flowing and the phases such as heat transfer
The analysis that the system for closing physical phenomenon is done.And the cost of experimental method is huge, generally using less.The beginning of the sixties in 19th century, Fu
The rolling that your moral is put forward for the first time ship movement is theoretical.To in the 1950s, the research that wave disturbs ship achieve it is great
Breakthrough is the introducing of spectrum analysis method, and nineteen fifty-three, Pearson came (Pierson) and holy Denis (StDenis) two people will be used in
The theory that the communications field handles noise is applied to movement of the ship in irregular water wave, proposes that hull is transported in irregular water wave
Dynamic theoretical method.To in the six-freedom degree simulation study of hull, many semi-physical emulation platforms are used both at home and abroad, such as day
Vessel simulator, the attitude of ship control platform of the Maritime Affairs University Of Dalian etc. of this IHI company research and development, propose with the sine of rule
Wave replaces interference of the practical wave research wave to ship.The Wang Xi of the Central China University of Science and Technology in 2007 is with MATLAB software to root
Numerical simulation is carried out according to the hull heaving and pitching of modified strip theory, derives that Wigley ship model makees heaving in regular wave
The equation of movement and pitching.2011, the wave making that the influence of the Ni Chong of Shanghai Communications University this consideration free surface is carried out
Drag evaluation encrypts grid around hull when carrying out grid dividing, and using the grid near hull as with volume mesh one
It rises and does rigid motion, the navigation posture of S60 ship has been forecast using dynamic mesh model.2014, the Tao Yi of the Maritime Affairs University Of Dalian
Ship wave force model in the regular wave based on CFD is studied in culvert, it was demonstrated that using the technique study ship of CFD numerical simulation
Oceangoing ship wave force is feasible and result accuracy is higher.
Comprehensive forefathers are to ship with the research of wave motion, it is known that CFD approach is to ship with wave motion Field Flow Numerical Simulation
Reliability and accuracy can clearly obtain its Flow Field Distribution information compared to theoretical values calculating, compared to experimental method
Economic cost has been saved again.In addition it is known that wave is regarded as sine wave to carry out theoretical research by most scholar, but in reality
In the ocean of border, scholar points out that the wave of ship in motion is not centainly sine wave.
Summary of the invention
The purpose of the present invention is to provide a kind of from the wave simulated under true sea situation based on Dynamic mesh ship
With wave on course-and-bearing motion simulation method.
The technical solution of the invention is as follows:
One kind based on Dynamic mesh ship with wave the motion simulation method on course-and-bearing, it is characterized in that: include it is following
Step:
(1) governing equation of CFD is used:
Mass-conservation equation (1), momentum conservation equation (2) and energy conservation equation (3)；
Wherein ρ is density, and t is the time, and u is velocity vector, Su、SvAnd SwIt is the broad sense source item of momentum conservation equation,
In, u, v and w are the component of velocity vector u in the x, y and z directions respectively, and μ is dynamic viscosity, and λ is second viscosity；For viscosity
For the incompressible fluid of constant, source item zero；T indicates temperature, and k indicates fluid heat transferring coefficient, cpIndicate specific heat capacity, STIt indicates
Viscous dissipation heat, for incompressible fluid, heat exchange amount is smaller, can be neglected；
(2) turbulence model is established
In view of in navigation, density of sea water varies less ship, will not fluid flow generate influence outstanding, then can not
Compression fluid with when equal algorithm obtain Reynolds and be averaged Navier-Stokes equation are as follows:
Wherein ρ is density, and t is the time, and μ is dynamic viscosity, and p is pressure, SiIt is broad sense source item, the true speed of v fluid flowing
Degree,For average speed, v ' is the difference of Real Flow Field speed and average speed；
(3) VOF model is established
VOF model simulates two by solving the volumetric ratio of the individual equation of momentum and processing across each fluid in region
Kind or three kinds of immiscible fluids；Ship at sea has gas and liquid two phase flow when driving, at interface, passes through VOF method
To carry out analysis and solution to water and air interface；Since fluid has continuity, fluid can be regarded as by countless small unit groups
At continuous media every physical quantity of fluid can be gone out with mathematical description by space coordinate and the function of time；By the side VOF
The calculating of method obtains the continuity equation of each unit volume fraction of each phase, so that it may the freedom of Simulating Multiphase fluid-mixing
Surface；
(4) Dynamic mesh is used
Dynamic mesh is for simulating because rigid motion occurs for fluid domain boundary, and also or boundary deforms and causes to flow
Body domain can pass through User-Defined Functions with the time change flow field problem that deformation occurs, definition of the hull in FLUENT
UDF file defines the rigid motion of hull；Ship is moved with channel flow, can be deformed in boundary, then grid can be sent out
Changing, thus new grid must be generated using the smooth and reconfiguration technique in dynamic mesh；
In any one control volume, the integral conservation law of broad sense scalar Φ is [12]:
In formula, ρ is density；U is speed flowrate；ugFor the Grid Velocity of mobile grid；Γ is diffusion coefficient；SΦFor source
?；For the boundary of control volume V；
Time-derivative item in formula (6)-formula (9)；It can be write as with single order backward difference format:
In formula, n and n+1 are different time horizons；V on n+1 layern+1It is calculated by formula (7):
In formula, dV/dt is the time-derivative of control volume；In order to meet grid law of conservation, the time-derivative of control volume by
Formula (8) calculates:
In formula, nfFor the surface grids number for controlling volume；AjFor the area vector of face j；Dot product ug,j○AjIt is calculated by formula (9):
In formula, δ VjFor the spatial volume that control volume face j is inswept in time interval Δ t；
(5) computation model that ship navigates by water in channel flow
Assuming that ship navigates by water on channel flow sea, establish centered on ship, i.e., ship is always positioned at coordinate O point, with course line
Direction is the right-handed coordinate system of x-axis, i.e. the front-left of ship is y-axis, and surface is z-axis, and shape feature is respectively by captain L, ship
Wide BLIt is described with tri- parameters of moldeed depth D, mathematic(al) representation is as follows:
Parameter value therein are as follows:
Wigley ship model parameter list
| Captain L (m) | Beam BL(m) | Moldeed depth D (m) |
| 2 | 0.2 | 0.125 |
In this model, entire computational domain is two-dimensional rectangular, and a length of 14 meters, 4 meters wide, entrance is set as speed entrance, outlet
For pressure export, upper and lower interface is set as symmetrical border；Unstrctured grid division is carried out using GAMBIT convection current field areas, to ensure
The good capture of flow behavior in boundary layer, thus divided using non-uniformity interval, and appropriate net is carried out at liquid-gas interface
Lattice encryption；
(6) Simulation Strategy that ship navigates by water in channel flow
Numerical simulation is carried out with wave motion to ship using ANSYS FLUENT software, in navigation, hull Boundary motion
Rule is unknown, and can generate and couple with flow field around, thus writes UDF file to define the rotary inertia of hull, and beat
The rolling freedom degree of oceangoing ship of sailing simulates hull floading condition；Simulation and tracking to free surface use VOF method, the method
By calculating the liquid volume fraction tectonic movement interface of each grid cell, and then determine free surface position, it is with higher
Resolution ratio and precision；
The numerical simulation that ship navigates by water in wave, the back wave that the manufacture and boundary that need to carry out Numerical wave generate disappear
It removes；Numerical wavemaking is carried out using the second order Stoke wave of channel flow；Wave absorption uses numerical value beach model；
It is transient state unstable process that ship, which at sea moves, and turbulence model, which uses, captures preferably adverse pressure gradient flow field
SST K-W model is emulated；According to Wigley ship model, the computational domain grid of computational domain and ship is drawn using GAMBIT
Figure, and it is conducted into FLUENT, second order stoke wave is simulated, and then simulate movement feelings of the Wigley ship under this second order stoke wave
Condition.
The present invention obtains the time history image on corrugated, realizes the life of wave by simulation channel flow second order Stoke wave
At, propagate, deformation, wave absorption process.The feasibility that channel flow under VOF model makes wave is demonstrated, after simulation by image pair
Than the theoretical knowledge of second order Stoke wave, meet its kinetic theory, lays base with wave motion research for following ship
Plinth.In addition the present invention uses two-dimension unsteady state CFD approach, and the Viscous Flow navigated by water under the state of heading sea on direction to ship carries out
Numerical simulation, the results showed that the second order Stoke nonlinear wave simulated using CFD approach can simulate true sea situation, can be very well
Solution forefathers only use single order sine wave as input wave, so that experimental result is had more confidence level；Week is presented in resistant coefficient
The characteristics of phase property changes.The present invention is based on the two-dimension unsteady state CFD approaches of VOF method and high-precision scope of freedom capturing technology to use
In the analog study of ship sea-keeping in wave, provided centainly for motion study of the ship from now in six degree of freedom wave
Basis.
Detailed description of the invention
Present invention will be further explained below with reference to the attached drawings and examples.
Fig. 1 is hull water shed model figure.
Fig. 2 is the grid chart in hull basin.
Fig. 3 is Simulation Strategy flow chart.
Fig. 4 is second order Stoke wave simulation figure.
Fig. 5, Fig. 6, Fig. 7 are the scope of freedom waveform cloud atlas of different moments when ship navigates by water in second order Stoke wave respectively.
Fig. 8, Fig. 9, Figure 10 are that lateral resistance, longitudinal resistance and speed of the ship under the effect of second order Stoke wave are bent respectively
Line chart.
Specific embodiment
1 ship with wave motion numerical simulation mathematical model
The governing equation of 1.1 CFD
CFD (computational fluid dynamics) is shown by computer numerical value calculation and image, to include fluid flowing and
The analysis that the system of the relevant physical phenomenas such as heat transfer is done.CFD can be regarded as in fundamental flowing equations (conservation of mass side
Journey, momentum conservation equation, energy conservation equation) control under the numerical simulation of flowing can be answered by this numerical simulation
The fundamental physical quantity of each position in miscellaneous problem flow field.
Three big laws are abided by three dimensional fluid flowing in basin: mass conservation law, the law of conservation of momentum and the conservation of energy are fixed
Rule.The ship studied herein motion component on seawater face belongs to incompressible viscous fluid, is not related to substantially in research contents
The dissipation of heat is lost, so can not considered about law of conservation of energy.Governing equation is that this three big law of conservation exists
Mathematical description in hydrodynamics is presented as mass-conservation equation (1), momentum conservation equation (2) and energy conservation equation (3).
Wherein ρ is density, and t is the time, and u is velocity vector, Su、SvAnd SwIt is the broad sense source item of momentum conservation equation,
In, u, v and w are the component of velocity vector u in the x, y and z directions respectively, and μ is dynamic viscosity, and λ is second viscosity.For viscosity
For the incompressible fluid of constant, source item is generally zero.T indicates temperature, and k indicates fluid heat transferring coefficient, cpIndicate specific heat capacity, ST
Indicate viscous dissipation heat, for incompressible fluid, heat exchange amount is smaller, can be neglected.
1.2 turbulence model
Turbulence model is a kind of Complex Flows of nonlinearity, but people have been able to through certain numerical methods to rapids
Stream carries out simulation and obtains the result coincideing compared with actually forcing.Turbulent flow is a kind of physical phenomenon of extreme complexity, comprising irregular
Property, diffusivity, three-dimensional vortex fluctuates and dissipates.In simulation of turbulence flow the Reynolds method of average at most,
In view of in navigation, density of sea water varies less ship, will not fluid flow generate influence outstanding, then incompressible fluid
With when equal algorithm obtain Reynolds and be averaged Navier-Stokes equation are as follows:
Wherein ρ is density, and t is the time, and μ is dynamic viscosity, and p is pressure, SiIt is broad sense source item, the true speed of v fluid flowing
Degree,For average speed, v ' is the difference of Real Flow Field speed and average speed.
1.3 VOF models
VOF model simulates two by solving the volumetric ratio of the individual equation of momentum and processing across each fluid in region
Kind or three kinds of immiscible fluids.Ship at sea has gas and liquid two phase flow when driving, at interface, can be by the side VOF
Method to carry out analysis and solution to water and air interface.Since fluid has continuity, fluid can be regarded as by countless small units
The continuous media of composition can go out every physical quantity of fluid by space coordinate and the function of time with mathematical description.Pass through VOF
The calculating of method obtains the continuity equation of each unit volume fraction of each phase, so that it may Simulating Multiphase fluid-mixing from
By surface.
1.4 Dynamic mesh
Dynamic mesh is for simulating because rigid motion occurs for fluid domain boundary, and also or boundary deforms and causes to flow
Body domain can pass through User-Defined Functions with the time change flow field problem that deformation occurs, definition of the hull in FLUENT
UDF file defines the rigid motion of hull.Herein, ship is moved with channel flow, can be deformed in boundary, then
Grid can change, thus must generate new grid using the smooth and reconfiguration technique in dynamic mesh.
In any one control volume, the integral conservation law of broad sense scalar Φ are as follows:
In formula, ρ is density；U is speed flowrate；ugFor the Grid Velocity of mobile grid；Γ is diffusion coefficient；SΦFor source
?；For the boundary of control volume V.
Time-derivative item in formula (6)-formula (9).It can be write as with single order backward difference format:
In formula, n and n+1 are different time horizons.V on n+1 layern+1It is calculated by formula (7):
In formula, dV/dt is the time-derivative of control volume.In order to meet grid law of conservation, the time-derivative of control volume by
Formula (8) calculates:
In formula, nfFor the surface grids number for controlling volume；AjFor the area vector of face j.Dot product ug,j○AjIt is calculated by formula (9):
In formula, δ VjFor the spatial volume that control volume face j is inswept in time interval Δ t.
The computation model and Simulation Strategy that 2 ships navigate by water in channel flow
The computation model that 2.1 ships navigate by water in channel flow
Herein using widely used Wigley ship model as research object, folded mould Viscous Flow of the analysis based on CFD approach
The situation of change of resistance and speed of the ship in metres per second.Wigley ship model is widely used in Marine engineering, resistance analysis, hydrodynamic force coefficient
Analysis etc..It is now assumed that ship navigates by water on channel flow sea, establish centered on ship, i.e., ship is always positioned at coordinate O point, with course line
Direction is the right-handed coordinate system of x-axis, i.e. the front-left of ship is y-axis, and surface is z-axis, and shape feature is respectively by captain L, ship
Wide BLIt is described with tri- parameters of moldeed depth D, mathematic(al) representation is as follows:
Parameter value therein is shown in Table 1:
1 Wigley ship model parameter list of table
In this model, entire computational domain is two-dimensional rectangular, and a length of 14 meters, 4 meters wide, entrance is set as speed entrance, outlet
For pressure export, upper and lower interface is set as symmetrical border.Unstrctured grid division is carried out using GAMBIT convection current field areas, to ensure
The good capture of flow behavior in boundary layer, thus divided using non-uniformity interval, and appropriate net is carried out at liquid-gas interface
Lattice encryption.
The Simulation Strategy that 2.2 ships navigate by water in channel flow
Numerical simulation is carried out with wave motion to ship using ANSYS FLUENT software herein, in navigation, hull boundary
The characteristics of motion is unknown, and can generate and couple with flow field around,
Thus UDF file is write to define the rotary inertia of hull, and opens the rolling freedom degree of ship to hull floading condition
It is simulated.Simulation and tracking to free surface use VOF method, the liquid bulk that the method passes through each grid cell of calculating
Fraction tectonic movement interface, and then determine free surface position, resolution ratio and precision with higher[15]。
The numerical simulation that ship navigates by water in wave, the back wave that the manufacture and boundary that need to carry out Numerical wave generate disappear
It removes.Numerical wavemaking is carried out using the second order Stoke wave of channel flow herein.Wave absorption uses numerical value seabeach (Numerical Beach)
Model.
It is transient state unstable process that ship, which at sea moves, and turbulence model, which uses, captures preferably adverse pressure gradient flow field
SST K-W model is emulated.According to Wigley ship model, the computational domain grid of computational domain and ship is drawn using GAMBIT
Figure, and it is conducted into FLUENT, second order stoke wave is simulated, and then simulate movement feelings of the Wigley ship under this second order stoke wave
Condition, finally carries out analysis discussion, the Simulation Strategy of whole system as shown in scheme 3
3 analysiss of simulation result
3.1 channel flow wave simulations
The propagation of channel flow boundary wave conditions permit analog rule, irregular wave.Channel flow is provided with first-order linear wave
With high-order Stoke wave etc..In order to simulate true sea situation, and waveform becomes apparent from, carried out herein wavelength be 2m, wave height 0.4m,
The sunykatuib analysis of the second order Stoke wave at 0 ° of wave head angle.Its simulation result as shown in figure 4, the wave numerical value due to simulation is smaller, therefore
Scope of freedom wave amplitude is smaller, but can be clearly seen that the scope of freedom of second order Stoke wave in mal-distribution.
The sunykatuib analysis that 3.2 ships move in second order Stoke wave
Herein to Wigley ship type with speed V=1.5m/s, in the wave of wavelength v=3.85m wave amplitude A=0.01925m
In, (head sea) using to meet with wave-to-course angle as 180 degree regimes when flow field and floading condition simulated.The wave scale of the wave is 1 grade,
Smooth sea, (unrestrained 0-0.1 meters high, 1 grade of wind-force).Sea situation description are as follows: ripple or surge is existed simultaneously with ripplet, small wave
In fish scale-shaped, without the spray.Ordinary fishing boat slightly feels shake, and sea wind is still not enough to sailing boat to carry out.Fig. 5,6,7 are ship in single order
When being navigated by water under the promotion of linear wave, the scope of freedom waveform cloud atlas of different moments.
As seen from the figure, during back-propagation, wave fades away wave, and this phenomenon may be due to second order
Stoke wave interacts and couples with wave making when ship's navigation, finally fades away in wave absorption area, utilizes FLUENT software mould
The Stoke waveform drawn up is consistent substantially with theory.
It when ship's navigation, is influenced by wave force, rocks ship, Fig. 8,9,10 are that ship is horizontal and vertical
Resistance coefficient and ship close the change curve of speed, and ship lateral resistance coefficient is presented just in the presence of second order Stoke wave
The characteristics of string cyclically-varying, the later period is slowly stable at 0.And longitudinal resistance coefficient floats up and down 2.9, occurs after 5s larger
Amplitude vibrations.Roll angle when navigating by water of heading sea is smaller, can be ignored.It is 1.5m/s due to giving ship movement velocity herein,
Thus ship closes speed during entire movement and all fluctuates above or below 1.5m/s.
It, may be by wind speed, the influence of the various factors such as ocean current, so that ship must be since sea conditions are complicated and changeable
With irregular water wave movement, can be seen that by above analogue simulation, the second order Stoke simulated using CFD approach is non-thread
Property wave can simulate true sea situation, can solve forefathers only use single order sine wave as input wave, make experimental result more
Has confidence level, also to lay the foundation to research of the ship in six degree of freedom wave later, it can also be used to which ship seakeeping is ground
Study carefully.
4 conclusions
When riding the sea, ship can do oscillating motion with wave.When wave is larger, to the life security of ship's staff
Generation seriously affects, thus herein from true wave is simulated, influence of the wave to ship is studied, is ship in deep-sea
Motion study lays the foundation.Herein by simulation channel flow second order Stoke wave, the time history image on corrugated is obtained, is realized
The generation of wave, propagation, deformation, wave absorption process.The feasibility that channel flow under VOF model makes wave is demonstrated, after simulation
By the theoretical knowledge of image comparison second order Stoke wave, meet its kinetic theory, is studied for following ship with wave motion
It lays the foundation.In addition two-dimension unsteady state CFD approach is used herein, navigates by water the Viscous Flow on direction under the state of heading sea to ship
Carry out numerical simulation, the results showed that the second order Stoke nonlinear wave simulated using CFD approach can simulate true sea situation, energy
Very good solution forefathers only use single order sine wave as input wave, and experimental result is made to have more confidence level；Resistant coefficient is in
The characteristics of existing cyclically-varying.Two-dimension unsteady state CFD approach energy based on VOF method and high-precision scope of freedom capturing technology herein
For the analog study of ship sea-keeping in wave, one is provided for motion study of the ship from now in six degree of freedom wave
Fixed basis.
Claims (1)
1. one kind based on Dynamic mesh ship with wave the motion simulation method on course-and-bearing, it is characterized in that: include following step
It is rapid:
(1) governing equation of CFD is used:
Mass-conservation equation (1), momentum conservation equation (2) and energy conservation equation (3)；
Wherein ρ is density, and t is the time, and u is velocity vector, Su、SvAnd SwIt is the broad sense source item of momentum conservation equation, wherein u, v
It is the component of velocity vector u in the x, y and z directions respectively with w, μ is dynamic viscosity, and λ is second viscosity；It is constant for viscosity
Incompressible fluid, source item zero；T indicates temperature, and k indicates fluid heat transferring coefficient, cpIndicate specific heat capacity, STIndicate viscosity consumption
Heat dissipation, for incompressible fluid, heat exchange amount is smaller, can be neglected；
(2) turbulence model is established
In view of in navigation, density of sea water varies less ship, will not fluid flow generate influence outstanding, then it is incompressible
Fluid with when equal algorithm obtain Reynolds and be averaged Navier-Stokes equation are as follows:
Wherein ρ is density, and t is the time, and μ is dynamic viscosity, and p is pressure, SiIt is broad sense source item, v fluid flows true velocity,
For average speed, v ' is the difference of Real Flow Field speed and average speed；
(3) VOF model is established
VOF model simulated by solving the volumetric ratio of the individual equation of momentum and processing across each fluid in region two kinds or
Three kinds of immiscible fluids；Ship at sea has gas and liquid two phase flow when driving, at interface, by VOF method come pair
Water and air interface carries out analysis and solution；Since fluid has continuity, fluid can be regarded as and be made of countless small units
Continuous media can go out every physical quantity of fluid by space coordinate and the function of time with mathematical description；Pass through VOF method
It calculates, obtains the continuity equation of each unit volume fraction of each phase, so that it may the Free Surface of Simulating Multiphase fluid-mixing；
(4) Dynamic mesh is used
Dynamic mesh is for simulating because rigid motion occurs for fluid domain boundary, and also or boundary deforms and leads to fluid domain
With the time change flow field problem that deformation occurs, definition of the hull in FLUENT can pass through User-Defined Functions UDF
File defines the rigid motion of hull；Ship is moved with channel flow, can be deformed in boundary, then grid can become
Change, thus new grid must be generated using the smooth and reconfiguration technique in dynamic mesh；
In any one control volume, the integral conservation law of broad sense scalar Φ is [12]:
In formula, ρ is density；U is speed flowrate；ugFor the Grid Velocity of mobile grid；Γ is diffusion coefficient；SΦFor source item；
For the boundary of control volume V；
Time-derivative item in formula (6)-formula (9)；It can be write as with single order backward difference format:
In formula, n and n+1 are different time horizons；V on n+1 layern+1It is calculated by formula (7):
In formula, dV/dt is the time-derivative of control volume；In order to meet grid law of conservation, the time-derivative of control volume is by formula (8)
It calculates:
In formula, nfFor the surface grids number for controlling volume；AjFor the area vector of face j；Dot product ug,j○AjIt is calculated by formula (9):
In formula, δ VjFor the spatial volume that control volume face j is inswept in time interval Δ t；
(5) computation model that ship navigates by water in channel flow
Assuming that ship navigates by water on channel flow sea, establish centered on ship, i.e., ship is always positioned at coordinate O point, with the direction in course line
For the right-handed coordinate system of x-axis, i.e. the front-left of ship is y-axis, and surface is z-axis, and shape feature is respectively by captain L, beam BL
It is described with tri- parameters of moldeed depth D, mathematic(al) representation is as follows:
Parameter value therein are as follows:
Wigley ship model parameter list
In this model, entire computational domain is two-dimensional rectangular, and a length of 14 meters, 4 meters wide, entrance is set as speed entrance, is exported as pressure
Power outlet, upper and lower interface are set as symmetrical border；Unstrctured grid division is carried out using GAMBIT convection current field areas, to ensure boundary
The good capture of intrastratal flow characteristic, thus divided using non-uniformity interval, and carry out appropriate grid at liquid-gas interface and add
It is close；
(6) Simulation Strategy that ship navigates by water in channel flow
Numerical simulation is carried out with wave motion to ship using ANSYS FLUENT software, in navigation, hull Boundary motion rule
It is unknown, and can generates and couple with flow field around, thus writes UDF file to define the rotary inertia of hull, and open ship
The rolling freedom degree of oceangoing ship simulates hull floading condition；Simulation and tracking to free surface use VOF method, and the method passes through
The liquid volume fraction tectonic movement interface of each grid cell is calculated, and then determines free surface position, resolution with higher
Rate and precision；
The numerical simulation that ship navigates by water in wave, the elimination for the back wave that the manufacture and boundary that need to carry out Numerical wave generate；
Numerical wavemaking is carried out using the second order Stoke wave of channel flow；Wave absorption uses numerical value beach model；
It is transient state unstable process that ship, which at sea moves, and turbulence model, which is used, captures preferably SST K- to adverse pressure gradient flow field
W model is emulated；According to Wigley ship model, the computational domain grid chart of computational domain and ship is drawn using GAMBIT, and will
It imports FLUENT, simulates second order stoke wave, and then simulates motion conditions of the Wigley ship under this second order stoke wave.
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| CN201910150378.2A Withdrawn CN110020459A (en) | 2019-02-28 | 2019-02-28 | Based on Dynamic mesh ship with wave the motion simulation method on course-and-bearing |
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Cited By (8)
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| CN111159813A (en) * | 2019-12-18 | 2020-05-15 | 智慧航海（青岛）科技有限公司 | Simulation-based flow-solid coupling analysis method and system for ship slamming on wave |
| CN111222202A (en) * | 2020-01-19 | 2020-06-02 | 智慧航海（青岛）科技有限公司 | Automatic division method for ship body grids based on virtual test platform |
| CN111353253A (en) * | 2020-03-31 | 2020-06-30 | 温州科技职业学院 | Method for realizing multi-column waves with different parameters based on Flow-3D software simulated physical wave-making means |
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| CN112904742A (en) * | 2021-01-15 | 2021-06-04 | 上海海事大学 | Active compensation control method for irregular waves |
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- 2019-02-28 CN CN201910150378.2A patent/CN110020459A/en not_active Withdrawn
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| CN111159813A (en) * | 2019-12-18 | 2020-05-15 | 智慧航海（青岛）科技有限公司 | Simulation-based flow-solid coupling analysis method and system for ship slamming on wave |
| CN111222202A (en) * | 2020-01-19 | 2020-06-02 | 智慧航海（青岛）科技有限公司 | Automatic division method for ship body grids based on virtual test platform |
| CN111222202B (en) * | 2020-01-19 | 2023-08-01 | 智慧航海（青岛）科技有限公司 | Automatic ship grid dividing method based on virtual test platform |
| CN111353253A (en) * | 2020-03-31 | 2020-06-30 | 温州科技职业学院 | Method for realizing multi-column waves with different parameters based on Flow-3D software simulated physical wave-making means |
| CN111353253B (en) * | 2020-03-31 | 2020-12-01 | 温州科技职业学院 | Method for realizing multi-column waves with different parameters based on Flow-3D software simulated physical wave-making means |
| CN111709625B (en) * | 2020-06-04 | 2023-05-26 | 上海佳豪船海工程研究设计有限公司 | Offshore operation rate evaluation system and method for piling ship |
| CN111709625A (en) * | 2020-06-04 | 2020-09-25 | 上海佳豪船海工程研究设计有限公司 | System and method for evaluating offshore operation rate of pile driving barge |
| CN112685976A (en) * | 2021-01-05 | 2021-04-20 | 西安交通大学 | Numerical simulation method of natural circulation system under motion condition |
| CN112904742A (en) * | 2021-01-15 | 2021-06-04 | 上海海事大学 | Active compensation control method for irregular waves |
| CN113505432B (en) * | 2021-06-15 | 2022-09-02 | 大连海事大学 | Method for directly calculating self-navigation point of water jet propulsion trimaran in random waves |
| CN113505432A (en) * | 2021-06-15 | 2021-10-15 | 大连海事大学 | Method for directly calculating self-navigation point of water jet propulsion trimaran in random waves |
| CN115440121A (en) * | 2022-10-21 | 2022-12-06 | 天津大学 | Open channel water flow connection virtual simulation experiment platform, method, system and application |
| CN115440121B (en) * | 2022-10-21 | 2024-03-22 | 天津大学 | Open channel water flow connection virtual simulation experiment platform, method, system and application |
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