ALE Kinematic Conditions

Boundary Conditions

Boundaries with Lagrangian materials are declared automatically Lagrangian.

Nodes can be declared Lagrangian.

Constraints can be applied separately or simultaneously on:
  • Material velocity
  • Grid velocity

These constraints can be applied in one or several directions of a skew reference frame.

When the flag is set to 1, boundary condition is activated with global reference frame or skew reference frame.
図 1.

i = DOF with respect to global reference frame or skew reference frame

VELOCITY: Vi = 0

ACCELERATION: π i = 0

The boundary conditions can be changed during Engine runs with /BCS or /BCSR Engine options.

ALE Links

An ALE link is identical to a rigid link. The secondary node sets' grid velocity can be controlled by two main nodes, M1 and M2.

There are three options to choose from:
Option 0
Velocity is linearly interpolated with respect to order of input.(1)
W N I = W M 1 + ( W M 2 W M 12 ) I N + 1 MathType@MTEF@5@5@+= feaagKart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbwvMCKf MBHbqefqvATv2CG4uz3bIuV1wyUbqedmvETj2BSbqefm0B1jxALjhi ov2DaebbnrfifHhDYfgasaacH8srps0lbbf9q8WrFfeuY=Hhbbf9v8 qqaqFr0xc9pk0xbba9q8WqFfea0=yr0RYxir=Jbba9q8aq0=yq=He9 q8qqQ8frFve9Fve9Ff0dmeaacaGacmGadaWaaiqacaabaiaafaaake aacaWGxbWaaSbaaSqaaiaad6eacaWGjbaabeaakiabg2da9iaadEfa daWgbaWcbaGaamytaiaaigdaaeqaaOGaaGjcVlaaykW7cqGHRaWkda qadaqaaiaadEfadaWgaaWcbaGaamytaiaaikdaaeqaaOGaeyOeI0Ia am4vamaaBaaaleaacaWGnbaabeaakmaaBaaaleaacaaIXaGaaGOmaa qabaaakiaawIcacaGLPaaadaWcaaqaaiaadMeaaeaacaWGobGaey4k aSIaaGymaaaaaaa@4F23@
Option 1
Velocity is set to maximum absolute velocity of main nodes.(2)
W N I = W M 1 if | W M 1 | < | W M 2 | MathType@MTEF@5@5@+= feaagKart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq=Jc9 vqaqpepm0xbba9pwe9Q8fs0=yqaqpepae9pg0FirpepeKkFr0xfr=x fr=xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGaam4vamaaBa aaleaacaWGobGaamysaaqabaGccqGH9aqpcaWGxbWaaSbaaSqaaiaa d2eacaaIXaaabeaakiaaywW7caqGPbGaaeOzaiaaywW7daabdaqaai aadEfadaWgaaWcbaGaamytaiaaigdaaeqaaaGccaGLhWUaayjcSdGa eyipaWZaaqWaaeaacaWGxbWaaSbaaSqaaiaad2eacaaIYaaabeaaaO Gaay5bSlaawIa7aaaa@4DC6@
Option 2
Velocity is set to minimum absolute velocity of main nodes.(3)
W N I = W M 1 if | W M 1 | < | W M 2 | MathType@MTEF@5@5@+= feaagKart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq=Jc9 vqaqpepm0xbba9pwe9Q8fs0=yqaqpepae9pg0FirpepeKkFr0xfr=x fr=xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGaam4vamaaBa aaleaacaWGobGaamysaaqabaGccqGH9aqpcaWGxbWaaSbaaSqaaiaa d2eacaaIXaaabeaakiaaywW7caqGPbGaaeOzaiaaywW7daabdaqaai aadEfadaWgaaWcbaGaamytaiaaigdaaeqaaaGccaGLhWUaayjcSdGa eyipaWZaaqWaaeaacaWGxbWaaSbaaSqaaiaad2eacaaIYaaabeaaaO Gaay5bSlaawIa7aaaa@4DC6@
The input data is specified at each restart run.