*AIRBAG_PARTICLE

LS-DYNA Input Interface KeywordDefines a Finite Volume Method airbag.

Format

(1) (2) (3) (4) (5) (6) (7) (8)
*AIRBAG_PARTICLE_{OPTION}
If OPTION = ID, insert the following line
(1) (2) (3) (4) (5) (6) (7) (8)
monvol_ID Title
(1) (2) (3) (4) (5) (6) (7) (8)
surf_IDex Surf_type_ex surf_IDin Surf_type_in
Text Pext Nvent Tswitch
Iair Ngas Ninj
Add Nvent cards for each vent
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surf_IDv Surf_type_v Avent FUNCT_ID FUNCP_ID
If Iair > 0, add the card
(1) (2) (3) (4) (5) (6) (7) (8)
Pair Tair Mw_air A_air B_air C_air
Add Ngas cards for definition of multi-component gas injection
(1) (2) (3) (4) (5) (6) (7) (8)
FM_ID (I) FT_ID (I) Mw (I) A (I) B (I) C (I)
Add Ninj cards for definition of injection holes through shell elements on external surface
(1) (2) (3) (4) (5) (6) (7) (8)
EID (I) VID (I)

Definition

Field Contents SI Unit Example
OPTION
ID
monvol_ID Airbag identifier.

(Integer)

Title Title.

(Character)

surf_IDex Airbag external surface identifier.

(Integer)

Surf_type_ex External set type.
= 0 (Default)
The surf_IDex is a segment set.
0
The surf_IDex is a set of parts.

(Integer)

surf_IDin Airbag internal surface identifier.

(Integer)

Surf_type_in Internal set type.
= 0 (Default)
The surf_IDin is a segment set.
0
The surf_IDin is a set of parts.

(Integer)

Text External temperature.

Default = 295 K (Real)

[ K ]
Pext External pressure.

(Real)

[ Pa ]
Nvent Number of vent holes.

(Integer)

Tswitch Time to switch from finite volume airbag to uniform pressure airbag.

(Real)

[ s ]
Iair Material definition for external air.
= 0 (Default)
Predefined material for air created.
> 0
Air material is created according to the airbag card input.

(Integer)

Ngas Number of injected gas components.

(Integer)

Ninj Number of injection holes.

(Integer)

surf_IDv Airbag vent surface identifier.

(Integer)

Surf_type_v Surface set type.
= 0 (Default)
The surf_IDv is a part ID.
0
The surf_IDv is a set of parts.

(Integer)

Avent Scaling coefficient for vent area.

Default = 1 (Real)

FUNCT_ID Function identifier for vent area scaling coefficient as function of time.

(Integer)

FUNCP_ID Function identifier for vent area scaling coefficient as function of overpressure.

(Integer)

Pair External pressure (overwrites Pext).

Default = Pext (Real)

[ Pa ]
Tair External temperature (overwrites Text).

Default = Text (Real)

[ K ]
MW_air Molar molecular weight of air.

(Real)

A_air Constant head capacity parameter for air.

(Real)

J mole MathType@MTEF@5@5@+= feaahqart1ev3aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq=Jc9 vqaqpepm0xbba9pwe9Q8fs0=yqaqpepae9pg0FirpepeKkFr0xfr=x fr=xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaWaamWaaeaada WcaaqaaiaabQeaaeaacaqGTbGaae4BaiaabYgacaqGLbaaaaGaay5w aiaaw2faaaaa@3C7C@
B_air Linear head capacity parameter for air.

(Real)

[ J mole .K ] MathType@MTEF@5@5@+= feaagKart1ev2aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq=Jc9 vqaqpepm0xbba9pwe9Q8fs0=yqaqpepae9pg0FirpepeKkFr0xfr=x fr=xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaWaamWaaeaada WcaaqaaiaabQeaaeaacaqGTbGaae4BaiaabYgacaqGLbGaaeOlaiaa bUeaaaaacaGLBbGaayzxaaaaaa@3DFE@
C_air Quadratic head capacity parameter for air.

(Real)

[ J m o l e K 2 ] MathType@MTEF@5@5@+= feaagKart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq=Jc9 vqaqpepm0xbba9pwe9Q8fs0=yqaqpepae9pg0FirpepeKkFr0xfr=x fr=xb9adbaqaaeaaciGaaiaabeqaamaabaabaaGcbaWaamWaaeaada WcaaqaaiaadQeaaeaacaWGTbGaam4BaiaadYgacaWGLbGaeyyXICTa am4samaaCaaaleqabaGaaGOmaaaaaaaakiaawUfacaGLDbaaaaa@4093@
FM_ID (I) Function identifier of gas component mass flow as function of time.

(Integer)

FT_ID (I) Function identifier of gas component temperature as function of time.

(Integer)

MW (I) Molar molecular weight of gas component.

(Real)

A (I) Constant head capacity parameter for gas component.

(Real)

J mole MathType@MTEF@5@5@+= feaahqart1ev3aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq=Jc9 vqaqpepm0xbba9pwe9Q8fs0=yqaqpepae9pg0FirpepeKkFr0xfr=x fr=xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaWaamWaaeaada WcaaqaaiaabQeaaeaacaqGTbGaae4BaiaabYgacaqGLbaaaaGaay5w aiaaw2faaaaa@3C7C@
B (I) Linear head capacity parameter for gas component.

(Real)

[ J mole .K ] MathType@MTEF@5@5@+= feaagKart1ev2aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq=Jc9 vqaqpepm0xbba9pwe9Q8fs0=yqaqpepae9pg0FirpepeKkFr0xfr=x fr=xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaWaamWaaeaada WcaaqaaiaabQeaaeaacaqGTbGaae4BaiaabYgacaqGLbGaaeOlaiaa bUeaaaaacaGLBbGaayzxaaaaaa@3DFE@
C (I) Quadratic head capacity parameter for gas component.

(Real)

[ J m o l e K 2 ] MathType@MTEF@5@5@+= feaagKart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq=Jc9 vqaqpepm0xbba9pwe9Q8fs0=yqaqpepae9pg0FirpepeKkFr0xfr=x fr=xb9adbaqaaeaaciGaaiaabeqaamaabaabaaGcbaWaamWaaeaada WcaaqaaiaadQeaaeaacaWGTbGaam4BaiaadYgacaWGLbGaeyyXICTa am4samaaCaaaleqabaGaaGOmaaaaaaaakiaawUfacaGLDbaaaaa@4093@
EID (I) Shell element number defining position of injector.

(Integer)

[ J kgK ] MathType@MTEF@5@5@+= feaagKart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq=Jc9 vqaqpepm0xbba9pwe9Q8fs0=yqaqpepae9pg0FirpepeKkFr0xfr=x fr=xb9adbaqaaeaaciGaaiaabeqaamaabaabaaGcbaWaamWaaeaada WcaaqaaiaabQeaaeaacaqGRbGaae4zaiabgwSixlaabUeaaaaacaGL BbGaayzxaaaaaa@3DB3@
VID (I) Initial direction of gas inflow at nozzle.
= -1 (Default)
Direction of gas inflow is in shell normal direction.
= -2
Direction of gas inflow is reversed relative to shell normal.

(Integer)

[ J kgK ] MathType@MTEF@5@5@+= feaagKart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq=Jc9 vqaqpepm0xbba9pwe9Q8fs0=yqaqpepae9pg0FirpepeKkFr0xfr=x fr=xb9adbaqaaeaaciGaaiaabeqaamaabaabaaGcbaWaamWaaeaada WcaaqaaiaabQeaaeaacaqGRbGaae4zaiabgwSixlaabUeaaaaacaGL BbGaayzxaaaaaa@3DB3@

Comments

  1. This keyword maps to /MONVOL/FVMBAG2, /MAT/GAS, and /PROP/INJECT1.
  2. External surfaces of airbag should form a closed volume.
  3. Airbag external and internal surfaces should not have any intersections.
  4. Injector holes are defined by shell elements on external surfaces.