Processing math: 100%

/DFS/LASER

Block Format Keyword Enable to model laser impact taking into account laser-matter interaction. 1

Format

(1) (2) (3) (4) (5) (6) (7) (8) (9) (10)
/DFS/LASER/laser_ID/unit_ID
SLAS fct_IDLAS STAR fct_IDTAR      
Hn VCp K0   Rd   KS  
Np Nc                
IEL1 IEL2 IEL3 IEL4 IEL5 IEL6 IEL7 IEL8 IEL9 IEL10
IEL11 etc IELNp              

Definitions

Field Contents SI Unit Example
laser_ID Laser line identifier.

(Integer, maximum 10 digits)

 
unit_ID Unit Identifier

(Integer, maximum 10 digits)

 
SLAS Laser intensity scale factor.

(Real)

 
fct_IDLAS Laser intensity time function number.

(Real)

 
STAR Target absorption scale factor.

(Real)

 
fct_IDTAR Target absorption temperature function number.

(Integer)

[K]
Hn Plasma parameter.

Hn=hvkB

Where,
h
Planck constant.
kB
Boltzmann constant.
v
Laser frequency.

(Real)

[K]
VCp Enthalpy of vaporization.

(Real)

[JkgK]
K0 Inverse bremsstrahlung coefficient K0. 6

(Real)

[m5]
Rd Inverse bremsstrahlung coefficient RdkB . 6

(Real)

[K]
KS Compliment absorption in vapor. 5

(Real)

[m5mole2]
Np Number of plasma elements between laser and target.

(Integer)

 
Nc Target element number. 1

(Integer)

 
IELi List of plasma elements (i=1,..., Np). 3

(Integer)

 

Comments

  1. Laser-matter interaction requires material laws enabling different phases: solid, liquid, and gas. It also needs to have a correct behavior with high pressure (several megabars) and high temperatures (more than 10000K). /MAT/LAW26 (SESAM) must also be used.
  2. This option is available only in 2D analysis.
  3. Plasma elements must be entered in the order from laser to target.
  4. It is assumed the laser beam is perpendicular to the target.
  5. KS=67000(ρwA)2 is taken from K. Daree's plasma ignition model.
  6. (1)
    I=I0ntargetnlaserIabsorbed
    (2)
    Iabsorbed=(1eKΔx)I
    (3)
    K=432π3kBTneniZ2e6hcm32ev3(1ehvkBT)gff=K0(Rdhv)3(RdkBT)12(n2iZ3)(1ehvkBT)gff

    Usually, K0=9.468×104m5 and Rdk=157750K .