dtsph.F

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!||====================================================================
!||    dtsph      ../starter/source/materials/time_step/dtsph.F
!||--- called by ------------------------------------------------------
!||    dt105law   ../starter/source/materials/time_step/dt105law.F
!||    dt10law    ../starter/source/materials/time_step/dt10law.F
!||    dt14law    ../starter/source/materials/time_step/dt14law.F
!||    dt1law     ../starter/source/materials/time_step/dt1law.F
!||    dt21law    ../starter/source/materials/time_step/dt21law.F
!||    dt34law    ../starter/source/materials/time_step/dt34law.F
!||    dt37law    ../starter/source/materials/time_step/dt37law.F
!||    dt38law    ../starter/source/materials/time_step/dt138aw.F
!||    dt3law     ../starter/source/materials/time_step/dt3law.F
!||    dt42law    ../starter/source/materials/time_step/dt42law.F
!||    dt51law    ../starter/source/materials/time_step/dt51law.F
!||    dt5law     ../starter/source/materials/time_step/dt5law.F
!||    dt6law     ../starter/source/materials/time_step/dt6law.F
!||    dt70law    ../starter/source/materials/time_step/dt70law.F
!||====================================================================
      SUBROUTINE dtsph(SSP,PM,GEO,PID,MAT, 
     .     RHO0, VIS, 
     .     DELTAX, VOL, DTX)
C------------------------
C     CALCUL DT ELEMENT
C-----------------------------------------------
C   I m p l i c i t   T y p e s
C-----------------------------------------------
#include      "implicit_f.inc"
C-----------------------------------------------
C   G l o b a l   P a r a m e t e r s
C-----------------------------------------------
#include      "mvsiz_p.inc"
C-----------------------------------------------
C   C o m m o n   B l o c k s
C-----------------------------------------------
#include      "vect01_c.inc"
#include      "param_c.inc"
C-----------------------------------------------
C   D u m m y   A r g u m e n t s
C-----------------------------------------------
      my_real
     .     ssp(*), pm(npropm,*),geo(npropg,*), rho0(*), vis(*), 
     .     deltax(*), vol(*), dtx(*)
      INTEGER PID(*),MAT(*)
C-----------------------------------------------
C   L o c a l   V a r i a b l e s
C-----------------------------------------------
      INTEGER I
C     REAL
      my_real
     .   cx(mvsiz), qx(mvsiz), al(mvsiz), 
     .    qa, qb, cns1, cns2
C=======================================================================
      DO i=lft,llt
        cx(i)=ssp(i)
      END DO
 
      DO i=lft,llt
      al(i)=vol(i)**third
      END DO
 
      DO i=lft,llt
        qa  =geo(14,pid(i))
        qb  =geo(15,pid(i))
        cns1=geo(16,pid(i))
        cns2=geo(17,pid(i))*ssp(i)*al(i)*rho0(i)
        qx(i)=(qb+cns1)*ssp(i)+(two*vis(i)+cns2)/(rho0(i)*deltax(i))
      ENDDO
 
      DO i=lft,llt
         dtx(i)=deltax(i)/
     .          max(em20,qx(i)+sqrt(qx(i)*qx(i)+cx(i)*cx(i)))
      END DO
c-----------
      RETURN
      END