/SPH/INOUT

Block Format Keyword Describes the SPH inlet/outlet conditions.

Format

(1) (2) (3) (4) (5) (6) (7) (8) (9) (10)
/SPH/INOUT/condition_ID
condition_name
Ityp part_ID surf_ID Dist node_ID1 node_ID2 node_ID3 Fcut
Input read only if surf_ID = 0, node_ID1 = 0, node_ID2 = 0 and node_ID3 = 0 22, 23, 24
(1) (2) (3) (4) (5) (6) (7) (8) (9) (10)
XM YM ZM        
XM1 YM1 ZM1        
XM2 YM2 ZM2        
Ityp =1 - General Inlet 12 through 16
(1) (2) (3) (4) (5) (6) (7) (8) (9) (10)
fct_IDr Fscaler       fct_IDE FscaleE  
fct_IDVn                  
Ityp =2 - General Outlet 17, 18, 19
(1) (2) (3) (4) (5) (6) (7) (8) (9) (10)
      fct_IDP FscaleP        
Blank Format
Ityp =3 - Non-Reflective Frontiers (NRF) 19, 20, 21
(1) (2) (3) (4) (5) (6) (7) (8) (9) (10)
      fct_IDP FscaleP l c    
Blank Format

Definitions

Field Contents SI Unit Example
condition_ID Inlet/Outlet condition identifier

(Integer, maximum 10 digits)

 
condition_name Inlet/Outlet condition name

(Character, maximum 100 characters)

 
Ityp Condition type 22 24
=1
General inlet. the surface must be meshed, only a surface Id can be input.
=2
General outlet
=3
Non-reflective frontiers (NRF)
=4
Control section. Control tool, only used for mass flux measurement.

(Integer)

 
part_ID Part identifier is used in order to define the SPH particles concerned by the condition.

(Integer)

 
surf_ID Surface identifier

(Integer)

 
Dist Distance from the surface for particle control

(Real)

[ m ]
node_ID1 Optional ID of node 1 (Itype ≠ 1)

(Integer)

 
node_ID2 Optional ID of node 2 (Itype ≠ 1)

(Integer)

 
node_ID3 Optional ID of node 3 (Itype ≠ 1)

(Integer)

 
Fcut Optional Cutoff frequency (Itype ≠ 1)

Default = 0 (Real)

 
XM Optional X coordinate of M (Itype ≠ 1)

(Real)

 
YM Optional Y coordinate of M (Itype ≠ 1)

(Real)

 
ZM Optional Z coordinate of M (Itype ≠ 1)

(Real)

 
XM1 Optional X coordinate of M1 (Itype ≠ 1)

(Real)

 
YM1 Optional Y coordinate of M1 (Itype ≠ 1)

(Real)

 
ZM1 Optional Z coordinate of M1 (Itype ≠ 1)

(Real)

 
XM2 Optional X coordinate of M2 (Itype ≠ 1)

(Real)

 
YM2 Optional Y coordinate of M2 (Itype ≠ 1)

(Real)

 
ZM2 Optional Z coordinate of M2 (Itype ≠ 1)

(Real)

 
fct_IDr Function fr(t) identifier for density

(Integer)

 
Fscaler Density scale factor

Default = 0.0 (Real)

[ kg m 3 ]
fct_IDE Function fE(t) identifier for energy

(Integer)

 
FscaleE Energy per volume unit scale factor

Default = 0.0 (Real)

[ J m 3 ]
fct_IDVn Function fVn(t) identifier for velocity in normal direction

(Integer)

 
fct_IDP Function fP(t) identifier for pressure

(Integer)

 
FscaleP Pressure scale factor

Default = 1.0 (Real)

[ Pa ]
l c Characteristic length 21

(Real)

[ m ]

Comments

  1. The surface segments must be orientated so that their normal vectors point towards the interior of the domain.
  2. The surface must be fixed.
  3. In case of an inlet condition, the condition enters particles belonging to its related part, so long as inactive particles are available for this part. The behavior of the particles belonging to the part which is related to the condition is set with respect to the condition characteristics for all particles lying on the positive side of the surface, within the distance Dist from the inlet surface.
  4. In case of an outlet condition, the behavior of the particles belonging to the part which is related to the condition is set with respect to the condition characteristics for all particles lying on the negative side of the surface, within the distance Dist from the outlet surface. Such a particle is deactivated if it does not interact with any non-outgoing particle.
  5. A particle deactivated by an outlet condition can be re-used by an inlet condition acting on the same part for incoming.
  6. If using outlets, order = -1 is recommended in the relative SPH property.
  7. In case of an outlet, the initial net must be provided up to the distance of 2h down to the outlet surface (where h is the smoothing length into the relative property).
    In case of inlet or outlet, the distance must be large enough, in order to control incoming or outgoing particles within at least a distance of 2h.

    Image17
    Figure 1. Inlet/Outlet Conditions Organization Overview
  8. The domains defined by two inlet/outlet surfaces and distances must not overlap.
  9. It is recommended for both, inlets and outlets, particles to be initially defined and controlled within more than twice the smoothing length of the particles.
  10. Inlet/outlet conditions option is allowed for SPMD parallel version. Parallel Arithmetic (same numerical results obtained whatever the number of processors) is not guaranteed for inlet conditions.
  11. Each incoming particle belonging to the part which is related to the condition gets the same mass mp (defined into the geometrical property which is attached to the part).
    A particle belonging to this part is entered at the center of a surface segment each time t such that:(1)
    m p t l a s t t ρ ( t ) S i v ( t ) d t
    Where,
    Si
    Area of the segment
    ρ ( t ) and v ( t )
    The density and velocity of the incoming matier (Lines 2 and 3)
    tlast
    Time at last incoming through this segment

    It is recommended to use a regular surface mesh.

  12. If no inactive particle belonging to this part is available for incoming, the program stops and you should provide a larger set of inactive particles for this part.
  13. If a particle belonging to the part which is related to the condition lies on the positive side of the surface within the Dist, its velocity is set with respect to the data given at Line 5.
  14. If fct_IDr = 0, density of the incoming particles is set to: (2)
    ρ a = F s c a l e r
    else(3)
    ρ a = F s c a l e r f r ( t )
  15. If fct_IDE = 0, energy per volume unit of the incoming particles is set to E a = F s c a l e E , else E a = F s c a l e E f E ( t ) .
  16. If a particle belonging to the part which is related to the condition lies on the negative side of the surface within the Dist, its internal pressure is set with respect to the data given at Line 6.
  17. If the particle does not interact with any non-outgoing particle, the particle is deactivated.
  18. If fct_IDP = 0, internal pressure of the outgoing particles is set to the internal pressure of the closest particle lying above the outlet surface, else it is set to F s c a l e P f P ( t ) .
  19. If a particle belonging to the part which is related to the condition lies on the negative side of the surface within the Dist, its internal pressure is set with respect to the equation:
    (4)
    P t = ρ c V n t + c ( P P ) 2 l c
  20. If fct_IDP = 0, pressure in the far field P is set to FscaleP, else it is set to FscaleP fP(t).
  21. l c is the characteristic length, it allows to compute cutoff frequency f c as:
    (5)
    f c = c 4 π l c
  22. If Itype = 2, 3 or 4, the surface can be defined by a meshed surface (surf_ID > 0), by 3 nodes (node_ID1 > 0, node_ID2 > 0 and node_ID3 > 0) or by the coordinates of 3 nodes (M, M1 and M2).

    sect_paral
    Figure 2.
  23. If Itype = 2, 3 or 4 and if the surface is defined by 3 coordinates, then the surface will be fixed. If the surface is defined by a surface ID or by 3 nodes, the surface will move according to the displacement of the shell elements or nodes.
  24. If Itype = 2, 3 or 4, a computation of the total mass crossing the surface is automatically performed and can be plotted using /TH/SPH_FLOW.