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TWOPHASE Block

Short description of what the block is used for

Warning

This block is optional.

Flags Overview

Note

All flags and their description are included in the table below. A detailed description of which values are possible for each input flag follows.

Flag Required Description
NSEEDS No Nonnegative integer variable, determines the number of seeds. If it is 0, no discrete phase will be considered unless the massflow_part s has value larger than zero.
MASSFLOW_PART No Nonnegative real variable, determines the mass flow rate of the discrete phase. If it is 0, no discrete phase will be considered unless the nseeds has value larger than zero.
MULTICOMPONENT_EVAP No boolean variable, is .true. when considering multicomponent evaporation model for multiple liquid fuel mixture and .false. otherwise.
NUMBER_COMPONENTS No Nonnegative integer variable, determines the number of liquid fuel mixture components. It is allowed up to four components. It can be 1,2,3 or 4.
MOLFRAC_COMP No It is a one-row of nonnegative real array with a maximum of four values, corresponding to the number of components specified in the previous flag. The sum of these entries should be equal to one. For example: 0.7, 0.1, 0.1, 0.1.
ROSIN_RAMMLER No Boolean variable, is .true. when the Rosen Rammler distribution is considered, and false otherwise.
DIAM_MEAN No Nonnegative real variable, present the mean diameter of the Resin-Rammler distribution
DIAM_MIN No Nonnegative real variable, presents the minimum diameter of the Resin-Rammler distribution
DIAM_MAX No Nonnegative real variable, presents the maximum diameter of the Resin-Rammler distribution
SHAPEFACTOR No Nonnegative real variable, presents the shape factor of the Resin-Rammler distribution
TYPE_SEEDS No Nonnegative integer variable, describes the configuration and arrange-ment of the second phase
TWOPHASE_INIT_TYPE No Nonnegative integer variable can be any value between [0-12], describes the configuration and arrangement of the second phase.
DISCRETE_PHASE_INTEGRATOR No Nonnegative integer number can be 1, or 2. Where 1 for Euler 1st order backward method, and 2 for Runge-Kutta 4th order.
DENS_SEEDS No Nonnegative real number represents the density of the discrete phase in kg/m3
DIAM_SEEDS No Nonnegative real number represents the mean diameter of the discrete phase in m, in case of uniform distribution
TCRITICAL No It is a one-row of nonnegative real array with a maximum of four values, corresponding to the number of components specified in the previous flag. It represents the critical temperature (in Kelvin) of the liquid phase mixture.
TBOILING No It is a one-row of nonnegative real array with a maximum of four values, corresponding to the number of components specified in the previous flag. It represents the boiling temperature (in Kelvin) of the liquid phase mixture.
LATENT_HEAT_MOL No It is a one-row of nonnegative real array with a maximum of four values, corresponding to the number of components specified in the previous flag. It represents the evaporation enthalpy in J/mol of the liquid phase mixture.
CPLIQUID No Nonnegative real number represents the specific heat at constant pressure of the discrete phase mixture in J/(kg.K)
DETAIL_DROPLET_TRANSPORT_PRO No Boolean variable that is set to .true. when the detailed transport properties of the droplet should be calculated (e.g., mass and heat transfer numbers, Schmidt number, Sherwood number, etc.). It should be set to .false. if constant values are to be used instead.
DINO_DROPLET_MINIMUM_DIAM No Non-negative real parameter defining the minimum particle diameter. Any particle with a diameter below this threshold is considered massless and is assumed not to interact with the flow field.
INIT_TEMPERATURE_SEEDS No Nonnegative real number represents the initial temperature of the discrete phase mixture in K
INIT_SEEDS_VELX No Non-negative real parameter specifying the initial x-direction velocity of the discrete-phase droplet (m/s).
INIT_SEEDS_VELY No Non-negative real parameter specifying the initial y-direction velocity of the discrete-phase droplet (m/s).
INIT_SEEDS_VELZ No Non-negative real parameter specifying the initial z-direction velocity of the discrete-phase droplet (m/s).
COLLISION_STIFF No Non-negative real parameter specifying the collision stiffness parameter, works with the fully resolving moving particles simulation
TWO_WAY_COUPLING No Boolean flag: set to .true. to enable two-way coupling between the discrete and continuous phases; set to .false. to apply one-way coupling only.
TWO_WAY_START_IT No Non-negative integer parameter indicating the iteration from which two-way coupling becomes active.
MOM_TRANSFER No Boolean flag: set to .true. to enable two-way momentum coupling between the discrete and continuous phases; set to .false. to apply one-way momentum coupling only.
MASS_TRANSFER No Boolean flag: set to .true. to enable two-way mass transfer coupling between the discrete and continuous phases; set to .false. to apply one-way mass transfer coupling only
ENEG_TRANSFER No Boolean flag: set to .true. to enable two-way heat transfer coupling between the discrete and continuous phases; set to .false. to apply one-way heat transfer coupling only
SURFACEPOINT_MANUALLY No Boolean parameter enabling manual selection of the number of surface-distribution points when set to .true.; automatic/default behavior is used when .false..
NSURFPOINT No Non-negative integer parameter determines the number of points over the immersed body in fully resolved simulation
FORCING_TYPE No Non-negative integer parameter specifying the type of the force: 0 for static objects, and 1 for moving objects
DF_IBM_DATA No String variable, defines the name of a ASCII file describing a specific geometry of the immersed boundary with direct force method

Flags Details

Nseeds
  • Type: Integer (-)
  • Values: Whatever suits your simulation.
  • Default: 1
  • Decription:number of discrete phase particles/droplet that is imposed onto the domain for initialization.

Massflow_part
  • Type: Real (kg/s)
  • Values: Whatever suits your simulation.
  • Default: 1E-5 kg/s
  • Description: the mass flow rate of of discrete phase (particle or droplets) that is imposed onto the domain for initialization.

Multicomponent_evap
  • Type: boolean
  • Values: True/False
  • Default: False
  • Description:boolean variable, is .true. when considering multicomponent evaporation model for multiple liquid fuel mixture and .false. otherwise.

Number_components
  • Type: Integer
  • Values: 1,2,3, or 4
  • Default: 1 [-]
  • Description: Nonnegative integer variable, determines the number of liquid fuel mixture components. It is allowed up to four components. It can be 1,2,3 or 4.

Molfrac_comp
  • Type: Real
  • Values: [0-1.0]
  • Default: 1.0, 0.,0., 0.
  • Description: Mole fraction of multiple liquid fuel mixture. It is a one-row array with a maximum of four values, corresponding to the number of components specified in the previous flag. The sum of these entries should be equal to one. For example: 0.7, 0.1, 0.1, 0.1.

Rosin_rammler
  • Type: Logical
  • Values: True/False
  • Default: True
  • Description: Boolean varaible, is .true. when the Rosen Rammler distribution is considered, and false otherwise.

Diam_mean
  • Type: Real [m]
  • Values: Whatever suits your simulation.
  • Default: 10.D-6 [m]
  • Description:Nonnegative real variable, present the mean diameter of the Resin-Rammler distribution. It is recommended to be much smaller than the grid resolution

Diam_min
  • Type: Real [m]
  • Values: Whatever suits your simulation.
  • Default: 8.D-6 [m]
  • Description:Nonnegative real variable, present the minimum diameter of the Resin-Rammler distribution. It is recommended to be much smaller than the grid resolution

Diam_max
  • Type: Real [m]
  • Values: Whatever suits your simulation.
  • Default: 16.D-6 [m]
  • Description:Nonnegative real variable, present the maximum diameter of the Resin-Rammler distribution. It is recommended to be much smaller than the grid resolution

Shapefactor
  • Type: Real [-]
  • Values: Whatever suits your simulation.
  • Default: 3.2 [-]
  • Description:Nonnegative real variable, present the shape factor of the Resin-Rammler distribution. It is recommended to be between 1.0 to 10.0

Type_seeds
  • Type: Integer
  • Values: 0-4
  • Default: 2
  • Description:nonnegative integer variable, determines the type of the seeds. 0 corresponds to massless tracers; 1 represents point force solid particles; 2 represents non-resolved droplets; 3 represents resolved spheres; 4 represents resolved fixed objects.

Twophase_init_type
  • Type: Integer
  • Values: [0-12]
  • Default: 0
  • Description: nonnegative integer variable, describes the configuration and arrangement of the second phase. The following are available types
    • 0 ---> random distribusion
    • 1 ---> particles move up
    • 2 ---> particles move down
    • 3 ---> cluster sheet in the center
    • 4 ---> cluster sheet move as jet
    • 5 ---> temporally evolving jet of particles, randomlly distributed
    • 6 ---> spherical cloud of droplets
    • 7 ---> jet inlet spray (not coded yet)
    • 8 ---> two particles collide
    • 9 ---> one particle in the center
    • 10 ---> fixed objective
    • 11 ---> round spatially evolving jet
    • 12 ---> planar spatially evolving jet

Discrete_phase_integrator
  • Type: Integer
  • Values: 1 or 2
  • Default: 1
  • Description: Nonnegative integer number can be 1, or 2. Where 1 for Euler 1st order backward method, and 2 for Runge-Kutta 4th order.

Dens_seeds
  • Type: Real [kg/m3]
  • Values: Whatever suits your simulation.
  • Default: 851 [kg/m3]
  • Description:Nonnegative real number represents the density of the discrete phase in kg/m3

Diam_seeds
  • Type: Real [m]
  • Values: Value.
  • Default: 10.D-6 [m]
  • Description: Nonnegative real number represents the mean diameter of the discrete phase in m, in case of uniform distribution

Tcritical
  • Type: Real [K]
  • Values: Whatever suits your simulation.
  • Default: 351.39, 505.15, 0.0, 0.0,
  • Description: It is a one-row of nonnegative real array with a maximum of four values, corresponding to the number of components specified in the previous flag. It represents the critical temperature (in Kelvin) of the liquid phase mixture.

Tboiling
  • Type: Real [K]
  • Values: Whatever suits your simulation.
  • Default: 351.39, 505.15, 0.0, 0.0, [K]
  • Description: It is a one-row of nonnegative real array with a maximum of four values, corresponding to the number of components specified in the previous flag. It represents the boiling temperature (in Kelvin) of the liquid phase mixture.

Latent_heat_mol
  • Type: Real [J/mol]
  • Values: Whatever suits your simulation
  • Default: 38.56D3, 62.3D3, 0.d0, 0.d0 [J/mol]
  • Description:It is a one-row of nonnegative real array with a maximum of four values, corresponding to the number of components specified in the previous flag. It represents the evaporation enthalpy in J/mol of the liquid phase mixture.

Cpliquid
  • Type: Real [J/(kg.K]
  • Values: Whatever suits your simulation
  • Default: 2300.D0, [J/(kg.K)]
  • Description:Nonnegative real number represents the specific heat at constant pressure of the discrete phase mixture in J/(kg.K)

Detail_droplet_transport_pro
  • Type: Logical
  • Values: True/False
  • Default: True
  • Description: A Boolean variable that is set to .true. when the detailed transport properties of the droplet should be calculated (e.g., mass and heat transfer numbers, Schmidt number, Sherwood number, etc.). It should be set to .false. if constant values are to be used instead.

Dino_droplet_minimum_diam
  • Type: Real [m]
  • Values: 1.D-6 [m]
  • Default: 1.D-6 [m]
  • Description:Non-negative real parameter defining the minimum particle diameter. Any particle with a diameter below this threshold is considered massless and is assumed not to interact with the flow field.

Init_temperature_seeds
  • Type: Real [K]
  • Values: >300 [K]
  • Default: 300 [K]
  • Description: Nonnegative real number represents the initial temperature of the discrete phase mixture in K

Init_seeds_velx
  • Type: Real [m/s]
  • Values: Whatever suits your simulation
  • Default: 30 m/s
  • Description:Non-negative real parameter specifying the initial x-direction velocity of the discrete-phase droplet (m/s).

Init_seeds_vely
  • Type: Real [m/s]
  • Values: Whatever suits your simulation
  • Default: 30 m/s
  • Description:Non-negative real parameter specifying the initial y-direction velocity of the discrete-phase droplet (m/s).

Init_seeds_velz
  • Type: Real [m/s]
  • Values: Whatever suits your simulation
  • Default: 30 m/s
  • Description:Non-negative real parameter specifying the initial z-direction velocity of the discrete-phase droplet (m/s).

Collision_stiff
  • Type: Real [-]
  • Values: Whatever suits for your simulation
  • Default: 5.D5 [-]
  • Description: Non-negative real parameter specifying the collision stiffness parameter, works with the fully resolving moving particles simulation

Two_way_coupling
  • Type: Logical
  • Values: True/False
  • Default: True
  • Description: Boolean flag: set to .true. to enable two-way coupling between the discrete and continuous phases; set to .false. to apply one-way coupling only.

Two_way_start_it
  • Type: Integer [-]
  • Values: Whatever suits your simulation
  • Default: 1
  • Description:Non-negative integer parameter indicating the iteration from which two-way coupling becomes active.

Mom_transfer
  • Type: Logical
  • Values: True/False
  • Default: True
  • Description:Boolean flag: set to .true. to enable two-way momentum coupling between the discrete and continuous phases; set to .false. to apply one-way momentum coupling only

Mass_transfer
  • Type: Logical
  • Values: True/False
  • Default: True
  • Description:Boolean flag: set to .true. to enable two-way mass transfer coupling between the discrete and continuous phases; set to .false. to apply one-way mass transfer coupling only

Eneg_transfer
  • Type: Logical
  • Values: True/False
  • Default: True
  • Description:Boolean flag: set to .true. to enable two-way heat transfer coupling between the discrete and continuous phases; set to .false. to apply one-way heat transfer coupling only

Surfacepoint_manually
  • Type: Logical
  • Values: True/False
  • Default: False
  • Description:Boolean parameter enabling manual selection of the number of surface-distribution points when set to .true.; automatic/default behavior is used when .false. It works only in case of resolved body with direct force immersed boundary method.

Nsurfpoint
  • Type: Integer
  • Values: Whatever suits your simulation
  • Default: 10
  • Description: Non-negative Integer parameter determines the number of points over the immersed body in fully resolved simulation. Works with the direct force immersed boundary method

Forcing_type
  • Type: Integer
  • Values: 0 or 1
  • Default: 0
  • Description:Non-negative integer parameter specifying the type of the force: 0 for static objects, and 1 for moving objects. It works only with direct force immersed boundary method.

Df_ibm_data
  • Type: String
  • Values: 'file_name.dat'
  • Default: 'file_name.dat'
  • Description: String variable, defines the name of a ASCII file describing a specific geometry of the immersed boundary with direct force method

Flags, Details:

&NML_TWOPHASE
    NSEEDS=0,
    MASSFLOW_PART=2.631d-5,
    MULTICOMPONENT_EVAP=.true.,
    NUMBER_COMPONENTS=2,
    MOLFRAC_COMP= 0.9, 0.1, 0.0,0.0,
    ROSIN_RAMMLER=.true.,
    DIAM_MEAN=10.D-6,
    DIAM_MIN=8.D-6,
    DIAM_MAX=12.D-6,
    SHAPEFACTOR=3.2,
    TYPE_SEEDS=2,
    TWOPHASE_INIT_TYPE=12, 
    DISCRETE_PHASE_INTEGRATOR=1,
    DENS_SEEDS=851D0,               
    DIAM_SEEDS=11.D-6,
    TCRITICAL =514.0 , 647.09, 0.0, 0.0, 
    TBOILING  =351.39, 505.15, 0.0, 0.0, 
    LATENT_HEAT_MOL=38.56D3, 62.3D3, 0.d0,0.d0
    CPLIQUID=2300.D0, 
    DETAIL_DROPLET_TRANSPORT_PRO=.true.,
    DINO_DROPLET_MINIMUM_DIAM=1.D-6,
    INIT_TEMPERATURE_SEEDS=300,
    INIT_SEEDS_VELX=0.0D0,
    INIT_SEEDS_VELY=94.3D0,
    INIT_SEEDS_VELZ=0.0D0,
    COLLISION_STIFF=5.D5,
    TWO_WAY_COUPLING=.true.,
    TWO_WAY_START_IT=500,
    MOM_TRANSFER=.true.,
    MASS_TRANSFER=.true.,
    ENEG_TRANSFER=.true.,
    SURFACEPOINT_MANUALLY=.false.,                        
    NSURFPOINT=1752,  
    FORCING_TYPE=0,
    DF_IBM_DATA='fusiform_aneurysm.dat',
\