CN112765860A - Combustion simulation method for wind-blowing alcohol burner flame - Google Patents
Combustion simulation method for wind-blowing alcohol burner flame Download PDFInfo
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Abstract
The invention discloses a combustion simulation method of a wind-blowing alcohol lamp flame, which is characterized in that a grid is utilized to discretize a scene, a Navier-Stokes equation is decomposed into an external force item, a diffusion item, a advection item and a projection item by adopting a finite difference method, and two key factors of influence of thermal buoyancy and vortex force on the flame are particularly considered when the external force item is solved; the method comprises the steps of calculating resultant force of particles under the condition of introducing unilateral wind according to the Newton kinematics principle, performing linear interpolation on the speed, the temperature and the density of the particles at the center of the particles, recalculating the positions of the particles, storing updated particle attribute values in the centers of corresponding grid units, traversing the grid units to obtain the attribute values of the particles, drawing the attribute values in a scene in real time, and realizing dynamic simulation of the flame in a unilateral wind environment.
Description
Technical Field
The invention belongs to the technical field of interdisciplines combining computer graphics and virtual reality, and particularly relates to a combustion simulation method of a wind-blowing alcohol burner flame.
Background
Virtual simulation is an important research branch in computer graphics, and people and objects in a real scene are simulated by using a computer and displayed in a three-dimensional space mode, so that the interaction between the people and the computer is more intuitive. The flame simulation is widely applied to a plurality of fields such as education and teaching, game development, film production, military simulation training and the like. Particularly, in the field of middle school education, experiments such as chemistry, physics, biology and the like of the alcohol burner are widely used, explosion or fire can be caused, and certain danger exists.
At present, for the simulation of the wind-blown flame, the shape and the appearance of the flame are not very true, the phenomenon that the whole flame deviates from a normal movement track is caused, the local deformation of the flame is lacked, the flame is slightly rigid, and the authenticity is greatly reduced. Aiming at the problems, the influence of parameters such as buoyancy, pressure, vortical force, temperature, density and speed on the flame is researched, the shape of the flame of the alcohol burner in a unilateral wind environment is simulated and analyzed under the condition of introducing wind power, a unilateral wind blowing alcohol burner combustion simulation algorithm is designed, and the dynamic simulation of the shape of the flame in the unilateral wind environment is realized.
Disclosure of Invention
The invention aims to provide a combustion simulation method of a wind-blown alcohol burner flame, which is characterized in that the influence of parameters such as buoyancy, pressure, vortical force, temperature, density and speed on the flame is explored by analyzing the solving process of relevant parameters of a wind-blown alcohol burner flame model, the shape of the alcohol burner flame in a unilateral wind environment is simulated and analyzed under the condition of introducing wind power, a combustion simulation algorithm of the unilateral wind-blown alcohol burner flame is designed, and the problem of dynamic simulation of the shape of the flame in the unilateral wind environment is solved.
In order to achieve the purpose, the invention adopts the following technical scheme:
a combustion simulation method of a wind-blowing alcohol burner flame comprises the following steps:
step 1: initializing the attribute values of the speed, the temperature and the density of the flame particles, and acquiring the current central position and the speed, the temperature and the density of the current central position.
Step 2: the flame can be acted by various forces during combustion, the external force items mainly comprise buoyancy, self gravity, wind power, pressure and vortex force, then the Navier-Stokes equation is decomposed by means of a Helmholtz-Hodge method under the premise of following the mass conservation law, and the whole movement process of the flame is simulated through a diffusion item, an advection item and a projection item;
and step 3: when the flame is acted by wind, calculating resultant force of flame particles, the central position of the current flame particles and the speed, temperature and density of the position;
and 4, step 4: and calculating the new position of the flame particles subjected to the wind and the speed, the temperature and the density of the new position.
Further, the specific steps of step 1 include:
selecting a MAC (mark-and-cell method) with proper precision to discretize the scene, and then initializing the attribute values of the speed, the temperature and the density of the flame particles. Traversing the whole MAC grid unit to obtain the current central position PoscurAnd the velocity Vel of the current center positioncurTemperature TemcurDensity Dencur。
Further, the specific steps of step 2 are:
step 2.1: decomposing a Navier-Stokes equation by using a finite difference format, wherein the Navier-Stokes equation is shown as a formula (1):
in the formula (1), v represents the viscosity coefficient of the flame particles,
represents the gradient operator, u represents the velocity of the flame particle, ρ represents the density of the flame particle, pRepresenting the pressure intensity, f representing the external force of the flame, including self gravity, resistance, wind power and the like.
Step 2.2: solving an external force term, wherein the resultant force of the external force on the flame particles is f, and the calculation formula is as follows (2):
in the formula (2), the reaction mixture is,
is the change in the velocity of the flame particles,
is a change in time.
And calculating the temperature T of the flame particles by utilizing a cubic linear interpolation method, and storing the temperature T into a corresponding MAC grid unit. The calculation formula of the temperature T of the flame particles is shown as the formula (3):
T＝(1-t)*a+t*b
formula (3)
In the formula (3), a and b represent values obtained by previous interpolation.
Then, the thermal buoyancy is solved, and the formula is shown as the formula (4):
Ffloating body＝σ(T-T0)j-G-α·ρ
Formula (4)
In formula (4), σ represents buoyancy; t represents the temperature of the flame particle at that time; t is0Representing ambient temperature, with a default value of 0; j represents the vertical direction vector (0,1, 0); g represents gravity; alpha represents a buoyancy factor; ρ represents the density of the flame particles. When the temperature difference is larger, the thermal buoyancy is obtained to be larger.
Calculating the direction of the vortex, wherein the calculation formula is shown as the formula (5):
in the formula (5), N represents the direction of swirl
Representing the gradient operator and u representing the velocity of the flame particle.
After the vortex direction is calculated, the vortex force F between the flame particles can be calculatedVortex deviceThe calculation formula is shown in formula (6):
in the formula (6), ε represents the viscous dissipation by vortex, ΔxIs the difference in x-coordinate, N is the direction of the vortex,
is the gradient operator, u is the velocity of the flame particle.
Step 2.3: solving a diffusion term, wherein the mathematical expression form of the diffusion term is shown as the following formula (7):
in the formula (7), the reaction mixture is,
is the change in the velocity of the flame particles,
in the form of a change in time, for example,
is a gradient operator, u is the velocity of the flame particle, and v is the viscosity coefficient of the flame particle.
Solving the diffusion term by using the Euler method, and converting the above formula (7) into a formula (8) of the following form by adopting the Jacobi (Jacobi) iterative idea:
in the formula (8), α represents a diffusion factor of the flame for controlling the diffusion effect, β ═ α +4 is a constant, and x and b represent fields to be diffused.
Step 2.4: and solving an advection term, wherein the advection term represents the velocity field of the flame and represents the change of the flame particles convected by the velocity field in unit time. The MacCormack (MacCormack) method of the semi-Lagrange method is adopted for solving. Meanwhile, an alcohol burner flame is constructed based on a particle system, a particle emitter in a scene emits a certain number of flame particles in an active area, the flame particles are initialized and endowed with geometric attributes and non-geometric attributes, the flame particles move in the scene according to the initialized speed, and the flame particles with the service life value of 0 are deleted along with the gradual decrease of the service life, namely the complete life process of the death is completed. The mathematical expression form of the advection term is shown as formula (9):
in the formula (9), the reaction mixture is,
is the change in the velocity of the flame particles,
in the form of a change in time, for example,
is the gradient operator, u is the velocity of the flame particle.
The MacCormack method is shown in equation (10):
in the formula (10), A represents advection, ARWhich represents the opposite advection of the flow,
representing the velocity component of the flame,
represents the amount before advection,
represents the amount after advection of the fluid,
represents an intermediate amount.
Step 2.5: the projection terms represent the pressure and density values of the fire particles, and are the most time-consuming solution of the whole equation. However, for the simulation of the flame, the influence of the mutual collision between the flame particles on the shape of the flame is not particularly large, so that the mutual collision between the flame particles can be ignored, and the calculation amount of the system is reduced.
For solving the density rho of the flame particles, firstly, the central position pos (x) of the MAC grid is obtained1,y1,z1) And reading the speed u of the flame particles recorded by the position grid unit, and calculating the position change of the flame particles within the time delta t, as shown in the formula (11).
pos(x2,y2,z2)＝pos(x1,y1,z1) -u.DELTA t formula (11)
And finally, carrying out three times of linear interpolation to obtain the density rho of the position, and storing the density value as an attribute value of the flame particle in the MAC grid unit.
Further, the step 3 specifically includes:
assuming that a left side wind exists in a scene, the Newton kinematics formula shows that the motion trajectory of the flame particles in an ideal environment deviates, and the stress F at the moment is shown as formula (12):
F＝Ffloating body+FWind power+G+FVortex device
Formula (12)
In the formula (12), FFloating bodyBuoyancy to which the flames are subjected, FWind powerWind force to which the flames are subjected, G gravity to which the flames are subjected, FVortex deviceThe flame is subjected to a vortex force.
Calculating the center position Pos of the flame particlemidThe calculation formula is shown in formula (13):
Posmid＝Poscur-Δt·Poscur/2
formula (13)
In formula (13), PoscurΔ t is the time interval for the previous center position.
At a central position PosmidRespectively carrying out linear interpolation on the velocity, temperature and density attributes of the flame particles to obtain the velocity Vel of the central positionmidTemperature TemmidDensity Denmid。
Further, the step 4 specifically includes:
calculating the new position Pos of the flame particlenewThe calculation formula is shown in formula (14):
Posnew＝Poscur-Δt·Velmid
formula (14)
In formula (14), PoscurΔ t is the time interval for the previous center position.
At a new position PosnewThe properties of the flame particles are subjected to linear interpolation to obtain new velocitiesDegree VelnewTemperature TemnewDensity DennewAnd storing the obtained new attribute value in the center of the corresponding MAC grid unit.
Compared with the prior art, the invention has the advantages and beneficial effects that:
according to the method, the influence of parameters such as buoyancy, pressure, vortex force, temperature, density and speed on the flame is explored by analyzing the solving process of the relevant parameters of the wind-blowing alcohol burner flame model, the shape of the flame of the alcohol burner flame in a unilateral wind environment is simulated and analyzed under the condition of introducing wind power, the combustion simulation algorithm of the unilateral wind-blowing alcohol burner flame is designed, and the problem of dynamic simulation of the shape of the flame in the unilateral wind environment is solved.
Drawings
Fig. 1 is a schematic 36 by 21 grid;
FIG. 2 is a schematic diagram of the analysis of the stress of the alcohol burner flame particles in a left wind environment;
FIG. 3 is a schematic diagram showing the movement law of particles of the alcohol lamp flames under the action of left wind;
FIG. 4 shows the simulation effect of 26 frames under different precision grids;
fig. 5 is a graph of the effect of different precision MAC grids on the simulation.
Detailed Description
The present invention will be further described with reference to the accompanying drawings and preferred embodiments, which are implemented on the premise of the technical solution of the present invention, and give detailed embodiments and procedures, but the scope of the present invention is not limited to the following embodiments.
The invention relates to a combustion simulation method of a wind-blowing alcohol burner flame, which is implemented according to the following steps:
step 1: initializing the speed, temperature, density and other attribute values of the flame particles;
step 1.1: and selecting a MAC grid with proper precision to discretize the scene. As shown in fig. 4, the effect of simulating flames when rendering to the 26 th frame is shown when discretizing the scene by grids with different precisions. As can be seen from FIG. 4, with the improvement of the grid precision, the grid cells are divided more finely, the stored flame particle attribute values are more accurate, and the simulation of the flame is more accurate and more real. Because the algorithm of the invention is that the MAC grid unit traversed by layers acquires the attribute value of the flame particle, the higher the grid precision is, as shown in FIG. 5, the frame frequency of the system is remarkably reduced, the more time is consumed, and the real-time performance is also remarkably reduced. Therefore, when the grid precision is 36 × 21, the simulation effect of the flame is more balanced in reality and real-time, so that the wind-blowing alcohol burner flame combustion simulation of the present invention is performed with the grid precision of 36 × 21 as shown in fig. 1.
Step 1.2: traversing the whole MAC grid unit to obtain the current central position PoscurAnd the velocity Vel of the current center positioncurTemperature TemcurDensity Dencur。
Step 2: the flame can be acted by various forces during combustion, the external force items mainly comprise buoyancy, self gravity, wind power, pressure and vortex force, then the equation is decomposed under the premise of following the mass conservation law by means of a Helmholtz-Hodge method, and the whole process of the movement of the flame is simulated through a diffusion item, a advection item and a projection item. The method comprises the following specific steps:
step 2.1: decomposing a Navier-Stokes equation by using a finite difference format, wherein the Navier-Stokes equation is shown as a formula (1):
in the formula (1), v represents the viscosity coefficient of the flame particles,
representing a gradient operator, u representing the speed of the flame particles, rho representing the density of the flame particles, p representing the pressure, and f representing the external force borne by the flame, including self gravity, resistance, wind power and the like.
Step 2.2: solving an external force term, wherein the resultant force of the external force on the flame particles is f, and the calculation formula is as follows (2):
in the formula (2), the reaction mixture is,
is the change in the velocity of the flame particles,
is a change in time.
And calculating the temperature T of the flame particles by utilizing a cubic linear interpolation method, and storing the temperature T into a corresponding MAC grid unit. The calculation formula of the temperature T of the flame particles is shown as the formula (3):
T＝(1-t)*a+t*b
formula (3)
In the formula (3), a and b represent values obtained by previous interpolation.
Then, the thermal buoyancy is solved, and the formula is shown as the formula (4):
Ffloating body＝σ(T-T0)j-G-α·ρ
Formula (4)
In formula (4), σ represents buoyancy; t represents the temperature of the flame particle at that time; t is0Representing ambient temperature, with a default value of 0; j represents the vertical direction vector (0,1, 0); g represents gravity; alpha represents a buoyancy factor; ρ represents the density of the flame particles. When the temperature difference is larger, the thermal buoyancy is obtained to be larger.
Calculating the direction of the vortex, wherein the calculation formula is shown as the formula (5):
in the formula (5), N represents the direction of swirl,
representing the gradient operator and u representing the velocity of the flame particle.
After the vortex direction is calculated, the vortex force F between the flame particles can be calculatedVortex deviceThe calculation formula is shown in formula (6):
in the formula (6), ε represents the viscous dissipation by vortex, ΔxIs the difference in x-coordinate, N is the direction of the vortex,
is the gradient operator, u is the velocity of the flame particle.
Step 2.3: solving a diffusion term, wherein the mathematical expression form of the diffusion term is shown as the following formula (7):
in the formula (7), the reaction mixture is,
is the change in the velocity of the flame particles,
in the form of a change in time, for example,
is a gradient operator, u is the velocity of the flame particle, and v is the viscosity coefficient of the flame particle.
Solving the diffusion term by using the Euler method, and converting the above formula (7) into a formula (8) of the following form by adopting the Jacobi (Jacobi) iterative idea:
in the formula (8), α represents a diffusion factor of the flame for controlling the diffusion effect, β ═ α +4 is a constant, and x and b represent fields to be diffused.
Step 2.4: and solving an advection term, wherein the advection term represents the velocity field of the flame and represents the change of the flame particles convected by the velocity field in unit time. The MacCormack method of the semi-Lagrange method is used for solving. Meanwhile, an alcohol burner flame is constructed based on a particle system, a particle emitter in a scene emits a certain number of flame particles in an active area, the flame particles are initialized and endowed with geometric attributes and non-geometric attributes, the flame particles move in the scene according to the initialized speed, and the flame particles with the service life value of 0 are deleted along with the gradual decrease of the service life, namely the complete life process of the death is completed. The mathematical expression form of the advection term is shown as formula (9):
in the formula (9), the reaction mixture is,
is the change in the velocity of the flame particles,
the time change is represented by a gradient operator, and u is the velocity of the flame particle.
The MacCormack method is shown in equation (10):
in the formula (10), A represents advection, ARWhich represents the opposite advection of the flow,
representing the velocity component of the flame,
represents the amount before advection,
represents the amount after advection of the fluid,
represents an intermediate amount.
Step 2.5: the projection terms represent the pressure and density values of the fire particles, and are the most time-consuming solution of the whole equation. However, for the simulation of the flame, the influence of the mutual collision between the flame particles on the shape of the flame is not particularly large, so that the mutual collision between the flame particles can be ignored, and the calculation amount of the system is reduced.
For solving the density rho of the flame particles, firstly, the central position pos (x) of the MAC grid is obtained1,y1,z1) And reading the speed u of the flame particles recorded by the position grid unit, and calculating the position change of the flame particles within the time delta t, as shown in the formula (11).
pos(x2,y2,z2)＝pos(x1,y1,z1) -u.DELTA t formula (11)
And finally, carrying out three times of linear interpolation to obtain the density rho of the position, and storing the density value as an attribute value of the flame particle in the MAC grid unit.
And 4, step 4: when the particle emitter randomly emits particles to a scene, the movement direction of the particles is acted by the gravity, buoyancy, wind power and the like of the particle emitter, as shown in fig. 2, the stress is more complex, and the movement state and the shape of the alcohol burner flame are changed accordingly. Assuming that there is a left side wind in the scene, as shown in fig. 3, it can be known by combining the newton kinematic formula that the trajectory of the flame particle in the ideal environment deviates, and the stress at this time is shown in equation (12).
F＝FFloating body+FWind power+G+FVortex device
Formula (12)
In the formula (12), FFloating bodyBuoyancy to which the flames are subjected, FWind powerWind force to which the flames are subjected, G gravity to which the flames are subjected, FVortex deviceThe flame is subjected to a vortex force.
Calculating the center position Pos of the flame particlemidThe calculation formula is shown in formula (13):
Posmid＝Poscur-Δt·Poscur/2
formula (13)
In formula (13), PoscurΔ t is the time interval for the previous center position.
At a central position PosmidRespectively carrying out linear interpolation on the velocity, temperature and density attributes of the flame particles to obtain the velocity Vel of the central positionmidTemperature TemmidDensity Denmid。
And 5: calculating the new position Pos of the flame particlenewThe calculation formula is shown in formula (14):
Posnew＝Poscur-Δt·Velmid
formula (14)
In formula (14), PoscurΔ t is the time interval for the previous center position.
At a new position PosnewRespectively carrying out linear interpolation on the attributes of the flame particles to obtain new velocity VelnewTemperature TemnewDensity DennewAnd storing the obtained new attribute value in the center of the corresponding MAC grid unit.
The above description is only a preferred embodiment of the present invention, but the scope of the present invention is not limited thereto. All equivalent changes, simplifications and modifications which do not depart from the spirit and scope of the invention are intended to be covered by the scope of the invention.
Claims (6)
1. A combustion simulation method of a wind-blowing alcohol burner flame is characterized by comprising the following steps:
step 1: initializing the attribute values of the speed, the temperature and the density of the flame particles, and acquiring the current central position and the speed, the temperature and the density of the current central position.
Step 2: decomposing a Navier-Stokes equation by an external force term applied to the flame during combustion by means of a Helmholtz-Hodge method under the premise of following a mass conservation law, and simulating the whole motion process of the flame by a diffusion term, an advection term and a projection term;
and step 3: when the flame is acted by wind, calculating resultant force of flame particles, the central position of the current flame particles and the speed, temperature and density of the position;
and 4, step 4: and calculating the new position of the flame particles subjected to the wind and the speed, the temperature and the density of the new position.
2. The method for simulating the combustion of a wind-blown alcohol burner flame as claimed in claim 1, wherein the specific steps of the step 1 comprise:
and selecting a MAC grid with proper precision to discretize the scene, and initializing the attribute values of the speed, the temperature and the density of the flame particles. Traversing the whole MAC grid unit to obtain the current central position PoscurAnd the velocity Vel of the current center positioncurTemperature TemcurDensity Dencur。
3. The method of claim 1, wherein in step 2, the external force term mainly comprises buoyancy, self-gravity, wind force, pressure, and vortex force.
4. The method for simulating combustion of a wind-blown alcohol burner flame according to claim 1 or 3, wherein the specific steps of the step 2 are as follows:
step 2.1: decomposing a Navier-Stokes equation by using a finite difference format, wherein the Navier-Stokes equation is shown as a formula (1):
in the formula (1), v represents the viscosity coefficient of the flame particles,
representing a gradient operator, u representing the speed of the flame particles, rho representing the density of the flame particles, p representing the pressure, and f representing the external force borne by the flame, including self gravity, resistance and wind power;
step 2.2: solving an external force term, wherein the resultant force of the external force on the flame particles is f, and the calculation formula is as follows (2):
in the formula (2), the reaction mixture is,
is the change in the velocity of the flame particles,
is a change in time;
calculating the temperature T of the flame particles by utilizing a cubic linear interpolation method, and storing the temperature T into a corresponding MAC grid unit, wherein the calculation formula of the temperature T of the flame particles is shown as the formula (3):
T＝(1-t)*a+t*b
formula (3)
In the formula (3), a and b represent values obtained by previous interpolation;
then, the thermal buoyancy is solved, and the formula is shown as the formula (4):
Ffloating body＝σ(T-T0)j-G-α·ρ
Formula (4)
In formula (4), σ represents buoyancy; t represents the temperature of the flame particle at that time; t is0Representing ambient temperature, with a default value of 0; j represents the vertical direction vector (0,1, 0); g represents gravity; alpha represents a buoyancy factor; ρ represents the density of the flame particles. When the temperature difference is larger, the obtained thermal buoyancy is larger;
calculating the direction of the vortex, wherein the calculation formula is shown as the formula (5):
in the formula (5), N represents the direction of swirl,
representing a gradient operator, and u represents the velocity of the flame particle;
after the vortex direction is calculated, the vortex force F between the flame particles is calculatedVortex deviceThe calculation formula is shown in formula (6):
in the formula (6), ε represents the viscous dissipation by vortex, ΔxIs the difference in x-coordinate, N is the direction of the vortex,
is a gradient operator, u is the velocity of the flame particle;
step 2.3: solving a diffusion term, wherein the mathematical expression form of the diffusion term is shown as the following formula (7):
in the formula (7), the reaction mixture is,
is the change in the velocity of the flame particles,
in the form of a change in time, for example,
is a gradient operator, u is the velocity of the flame particles, and v is the viscosity coefficient of the flame particles;
solving the diffusion term by using an Eulerian method, and converting the formula (7) into a formula (8) in the following form by adopting a Jacobi iteration thought:
in the formula (8), α represents a diffusion factor of a flame for controlling a diffusion effect, β ═ α +4 is a constant, and x and b represent fields to be diffused;
step 2.4: solving an advection term by adopting a MacCormack method of a half Lagrange method, meanwhile, constructing an alcohol burner flame based on a particle system, transmitting a certain number of flame particles in an active area by a particle transmitter in a scene, initializing the flame particles, endowing the flame particles with geometric attributes and non-geometric attributes, moving in the scene according to the initialized speed, and deleting the flame particles with the service life value of 0 along with the gradual decrease of the service life, namely completing the whole life process of the death; the mathematical expression form of the advection term is shown as formula (9):
in the formula (9), the reaction mixture is,
is the change in the velocity of the flame particles,
in the form of a change in time, for example,
is a gradient operator, u is the velocity of the flame particle;
the MacCormack method is shown in equation (10):
in the formula (10), A represents advection, ARWhich represents the opposite advection of the flow,
representing the velocity component of the flame,
represents the amount before advection,
represents the amount after advection of the fluid,
represents an intermediate amount;
step 2.5: solving the density rho of the flame particles, firstly obtaining the medium of the MAC gridHeart position pos (x)1,y1,z1) Reading the speed u of the flame particles recorded by the position grid unit, and calculating the position change of the flame particles within the time delta t, as shown in formula (11):
pos(x2,y2,z2)＝pos(x1,y1,z1) -u.DELTA t formula (11)
And finally, carrying out three times of linear interpolation to obtain the density rho of the position, and storing the density value as an attribute value of the flame particle in the MAC grid unit.
5. The method for simulating the combustion of a wind-blown alcohol burner flame according to claim 1, wherein the specific steps of the step 4 are as follows:
assuming that a left side wind exists in a scene, the Newton kinematics formula shows that the motion trajectory of the flame particles in an ideal environment deviates, and the stress F at the moment is shown as formula (12):
F＝Ffloating body+FWind power+G+FVortex device
Formula (12)
In the formula (12), FFloating bodyBuoyancy to which the flames are subjected, FWind powerWind force to which the flames are subjected, G gravity to which the flames are subjected, FVortex deviceThe flame is subjected to vortex force;
calculating the center position Pos of the flame particlemidThe calculation formula is shown in formula (13):
Posmid＝Poscur-Δt·Poscur/2
formula (13)
In formula (13), PoscurThe central position of the current surface is shown, and delta t is a time interval;
at a central position PosmidRespectively carrying out linear interpolation on the velocity, temperature and density attributes of the flame particles to obtain the velocity Vel of the central positionmidTemperature TemmidDensity Denmid。
6. The method for simulating the combustion of a wind-blown alcohol burner flame as claimed in claim 1, wherein the specific steps of the step 5 are as follows:
calculating the new position Pos of the flame particlenewThe calculation formula is shown in formula (14):
Posnew＝Poscur-Δt·Velmid
formula (14)
In formula (14), PoscurThe central position of the current surface is shown, and delta t is a time interval;
at a new position PosnewRespectively carrying out linear interpolation on the attributes of the flame particles to obtain new velocity VelnewTemperature TemnewDensity DennewAnd storing the obtained new attribute value in the center of the corresponding MAC grid unit.
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