FDS Source: add time ramp RAMP_ZETA_0 for INITIAL_UNMIXED_FRACTION on COMB

Author: rmcdermo

Source/cons.f90

@@ -439,6 +439,7 @@ MODULE GLOBAL_CONSTANTS
 INTEGER :: N_PASSIVE_SCALARS=0                                      !< Number of passive scalars
 INTEGER :: N_TOTAL_SCALARS=0                                        !< Number of total scalars, tracked and passive
 INTEGER :: N_FIXED_CHEMISTRY_SUBSTEPS=-1                            !< Number of chemistry substeps in combustion routine
+INTEGER :: ZETA_0_RAMP_INDEX=0                                      !< Ramp index for initial unmixed fraction
 
 LOGICAL :: OUTPUT_CHEM_IT=.FALSE.
 LOGICAL :: REAC_SOURCE_CHECK=.FALSE.

Source/fire.f90

@@ -96,12 +96,13 @@ SUBROUTINE COMBUSTION_GENERAL_LOAD_BALANCED(T,DT)
 USE PHYSICAL_FUNCTIONS, ONLY: GET_SPECIFIC_GAS_CONSTANT,GET_MASS_FRACTION_ALL,GET_SPECIFIC_HEAT,GET_MOLECULAR_WEIGHT, &
                               GET_SENSIBLE_ENTHALPY_Z,IS_REALIZABLE
 USE CHEMCONS, ONLY: DO_CHEM_LOAD_BALANCE
+USE MATH_FUNCTIONS, ONLY: EVALUATE_RAMP
 
 INTEGER :: NM,I,J,K,NC, CHEM_SUBIT_TMP,CHEM_SUBIT_TMP_OUT,ICC,JCC,INDX,NRECEIVE_CELLS
 INTEGER :: NCHEM_ACTIVE_CELLS_AND_CC, NCHEM_ACTIVE_CELLS_AND_CC_GLOBAL, IERR, NCHEM_ACTIVE_CELLS, NCHEM_ACTIVE_CC
 REAL(EB), INTENT(IN) :: T,DT
 REAL(EB) :: ZZ_GET(1:N_TRACKED_SPECIES),DZZ(1:N_TRACKED_SPECIES),&
-            REAC_SOURCE_TERM_TMP(N_TRACKED_SPECIES),Q_REAC_TMP(N_REACTIONS),VCELL,PRES
+            REAC_SOURCE_TERM_TMP(N_TRACKED_SPECIES),Q_REAC_TMP(N_REACTIONS),VCELL,PRES,ZETA_0,TSI
 LOGICAL :: Q_EXISTS
 TYPE (CC_CUTCELL_TYPE), POINTER :: CC
 LOGICAL :: IS_CHEM_ACTIVE
@@ -175,7 +176,10 @@ SUBROUTINE COMBUSTION_GENERAL_LOAD_BALANCED(T,DT)
 !       For 1 MPI process (serial) distribution is not needed.
 !------
 
- DO_CHEM_LOAD_BALANCE_IF : IF(N_MPI_PROCESSES > 1 .AND. DO_CHEM_LOAD_BALANCE) THEN
+TSI = T-T_BEGIN
+ZETA_0 = EVALUATE_RAMP(TSI,ZETA_0_RAMP_INDEX)*INITIAL_UNMIXED_FRACTION
+
+CHEM_LOAD_BALANCE_IF : IF(N_MPI_PROCESSES > 1 .AND. DO_CHEM_LOAD_BALANCE) THEN
    IF (.NOT. ALLOCATED(NCHEM_ACTIVE_CELLS_AND_CC_RANK_WISE)) ALLOCATE(NCHEM_ACTIVE_CELLS_AND_CC_RANK_WISE(N_MPI_PROCESSES))
    NCHEM_ACTIVE_CELLS_AND_CC_RANK_WISE = 0
    CALL MPI_ALLGATHER(NCHEM_ACTIVE_CELLS_AND_CC,1,MPI_INTEGER,NCHEM_ACTIVE_CELLS_AND_CC_RANK_WISE,1,MPI_INTEGER,MPI_COMM_WORLD,IERR)
@@ -205,7 +209,7 @@ SUBROUTINE COMBUSTION_GENERAL_LOAD_BALANCED(T,DT)
          ! Call combustion integration routine for Cartesian cell (I,J,K)
          CALL COMBUSTION_MODEL( T,DT,ZZ_GET,Q_OUT,MIX_TIME_OUT,CHI_R_OUT,&
                                 CHEM_SUBIT_TMP_OUT,REAC_SOURCE_TERM_TMP,Q_REAC_TMP,&
-                                MYTEMP,MYRHO,PRES,MYMU,DELTA,VOL)
+                                MYTEMP,MYRHO,PRES,MYMU,DELTA,VOL,ZETA_0)
          !***************************************************************************************
 
          RESULTS_TO_SEND_ARRAY(1:N_TRACKED_SPECIES,INDX) = ZZ_GET
@@ -216,7 +220,6 @@ SUBROUTINE COMBUSTION_GENERAL_LOAD_BALANCED(T,DT)
 
       ENDDO
 
-
       IF (COMBUSTION_ODE_SOLVER == CVODE_SOLVER) THEN
          T_CHEM_ODE = T_CHEM_ODE+CURRENT_TIME()-TNOW2
       ENDIF
@@ -230,7 +233,7 @@ SUBROUTINE COMBUSTION_GENERAL_LOAD_BALANCED(T,DT)
       IF (STOP_STATUS/=NO_STOP) RETURN
    ENDIF !NCHEM_ACTIVE_CELLS_AND_CC_GLOBAL >0
 
-ELSE DO_CHEM_LOAD_BALANCE_IF
+ELSE CHEM_LOAD_BALANCE_IF
 
    IF (NCHEM_ACTIVE_CELLS_AND_CC >0) THEN
       ! Serial chemistry:
@@ -254,7 +257,7 @@ SUBROUTINE COMBUSTION_GENERAL_LOAD_BALANCED(T,DT)
             CALL COMBUSTION_MODEL( T,DT,ZZ_GET,Q(I,J,K),MIX_TIME(I,J,K),CHI_R(I,J,K),&
                                    CHEM_SUBIT_TMP,REAC_SOURCE_TERM_TMP,Q_REAC_TMP,&
                                    TMP(I,J,K),RHO(I,J,K),PRES, MU(I,J,K),&
-                                   LES_FILTER_WIDTH(I,J,K),DX(I)*DY(J)*DZ(K),IIC=I,JJC=J,KKC=K )
+                                   LES_FILTER_WIDTH(I,J,K),DX(I)*DY(J)*DZ(K),ZETA_0,IIC=I,JJC=J,KKC=K )
             !***************************************************************************************
             !IF (STOP_STATUS/=NO_STOP) RETURN
             IF (OUTPUT_CHEM_IT) CHEM_SUBIT(I,J,K) = CHEM_SUBIT_TMP
@@ -278,7 +281,7 @@ SUBROUTINE COMBUSTION_GENERAL_LOAD_BALANCED(T,DT)
                                       CC%CHI_R(JCC),&
                                       CHEM_SUBIT_TMP,REAC_SOURCE_TERM_TMP,Q_REAC_TMP,&
                                       CC%TMP(JCC),CC%RHO(JCC),PRES,MU(I,J,K),&
-                                      LES_FILTER_WIDTH(I,J,K),CC%VOLUME(JCC),IIC=I,JJC=J,KKC=K)
+                                      LES_FILTER_WIDTH(I,J,K),CC%VOLUME(JCC),ZETA_0,IIC=I,JJC=J,KKC=K)
                !***************************************************************************************
                CALL SET_SPECIES_SOURCE_TERM_CUTCELL(DT, ICC, JCC, ZZ_GET, DZZ, REAC_SOURCE_TERM_TMP, Q_REAC_TMP)
             END DO
@@ -291,7 +294,7 @@ SUBROUTINE COMBUSTION_GENERAL_LOAD_BALANCED(T,DT)
          T_CHEM_ODE = T_CHEM_ODE+CURRENT_TIME()-TNOW2
       ENDIF
    ENDIF !NCHEM_ACTIVE_CELLS_AND_CC >0
-ENDIF DO_CHEM_LOAD_BALANCE_IF
+ENDIF CHEM_LOAD_BALANCE_IF
 
 ! This volume refactoring is needed for RADIATION_FVM (CHI_R, Q) and plotting slices:
 IF(CC_IBM) THEN
@@ -712,13 +715,13 @@ END SUBROUTINE GATHER_CELLS_FROM_MPI_PROCESSES
 
 
 SUBROUTINE COMBUSTION_MODEL(T,DT,ZZ_GET,Q_OUT,MIX_TIME_OUT,CHI_R_OUT,CHEM_SUBIT_OUT,REAC_SOURCE_TERM_OUT,Q_REAC_OUT,&
-                            TMP_IN,RHO_IN,PRES_IN,MU_IN,DELTA,CELL_VOLUME,IIC,JJC,KKC)
+                            TMP_IN,RHO_IN,PRES_IN,MU_IN,DELTA,CELL_VOLUME,ZETA_0_IN,IIC,JJC,KKC)
 USE MATH_FUNCTIONS, ONLY: EVALUATE_RAMP
 USE PHYSICAL_FUNCTIONS, ONLY: GET_REALIZABLE_MF
 USE COMP_FUNCTIONS, ONLY: SHUTDOWN
 USE CHEMCONS, ONLY: ODE_MIN_ATOL
 INTEGER, INTENT(IN), OPTIONAL :: IIC,JJC,KKC
-REAL(EB), INTENT(IN) :: T,DT,RHO_IN,PRES_IN,MU_IN,DELTA,CELL_VOLUME
+REAL(EB), INTENT(IN) :: T,DT,RHO_IN,PRES_IN,MU_IN,DELTA,CELL_VOLUME,ZETA_0_IN
 REAL(EB), INTENT(OUT) :: Q_OUT,MIX_TIME_OUT,CHI_R_OUT,REAC_SOURCE_TERM_OUT(N_TRACKED_SPECIES),Q_REAC_OUT(N_REACTIONS)
 INTEGER, INTENT(OUT) :: CHEM_SUBIT_OUT
 REAL(EB), INTENT(INOUT) :: ZZ_GET(1:N_TRACKED_SPECIES)
@@ -730,7 +733,7 @@ SUBROUTINE COMBUSTION_MODEL(T,DT,ZZ_GET,Q_OUT,MIX_TIME_OUT,CHI_R_OUT,CHEM_SUBIT_
             Q_REAC_SUM(1:N_REACTIONS),Q_SUM_CHI_R,CHI_R_SUM,TIME_RAMP_FACTOR,&
             TOTAL_MIXED_MASS_1,TOTAL_MIXED_MASS_2,TOTAL_MIXED_MASS_4,TOTAL_MIXED_MASS,&
             ZETA_1,ZETA_2,ZETA_4,D_F,TMP_IN,C_U,DT_SUB_OLD,ERR_EST(N_TRACKED_SPECIES),ERR_TOL(N_TRACKED_SPECIES),ERR_TINY,&
-            ZZ_TEMP(1:N_TRACKED_SPECIES), ATOL(1:N_TRACKED_SPECIES)
+            ZZ_TEMP(1:N_TRACKED_SPECIES),ATOL(1:N_TRACKED_SPECIES)
 INTEGER :: NR,NS,ITER,TVI,RICH_ITER,TIME_ITER,RICH_ITER_MAX
 INTEGER, PARAMETER :: TV_ITER_MIN=5
 LOGICAL :: TV_FLUCT(1:N_TRACKED_SPECIES),EXTINCT,NO_REACTIONS,NO_REAC_2,NO_REAC_4
@@ -761,7 +764,7 @@ SUBROUTINE COMBUSTION_MODEL(T,DT,ZZ_GET,Q_OUT,MIX_TIME_OUT,CHI_R_OUT,CHEM_SUBIT_
    END SELECT
 ENDIF
 
-ZETA_0 = INITIAL_UNMIXED_FRACTION
+ZETA_0 = ZETA_0_IN
 CELL_MASS = RHO_IN*CELL_VOLUME
 
 DT_SUB_MIN = DT/REAL(MAX_CHEMISTRY_SUBSTEPS,EB)

Source/read.f90

@@ -4492,11 +4492,12 @@ END SUBROUTINE PROC_SPEC_2
 SUBROUTINE READ_COMB
 USE CHEMCONS, ONLY: ODE_MIN_ATOL, EQUIV_RATIO_CHECK, MIN_EQUIV_RATIO, MAX_EQUIV_RATIO, DO_CHEM_LOAD_BALANCE
 REAL(EB) :: ODE_REL_ERROR
+CHARACTER(LABEL_LENGTH) :: RAMP_ZETA_0='null'
 NAMELIST /COMB/ CHECK_REALIZABILITY,COMPUTE_ADIABATIC_FLAME_TEMPERATURE, DO_CHEM_LOAD_BALANCE, EQUIV_RATIO_CHECK, &
                 EXTINCTION_MODEL,FINITE_RATE_MIN_TEMP, FIXED_MIX_TIME,FREE_BURN_TEMPERATURE,&
                 INITIAL_UNMIXED_FRACTION, MAX_CHEMISTRY_SUBSTEPS, MAX_EQUIV_RATIO, MIN_EQUIV_RATIO, &
                 N_FIXED_CHEMISTRY_SUBSTEPS, ODE_MIN_ATOL,ODE_REL_ERROR,ODE_SOLVER,SUPPRESSION,TAU_CHEM, &
-                TAU_FLAME,ZZ_MIN_GLOBAL
+                TAU_FLAME,RAMP_ZETA_0,ZZ_MIN_GLOBAL
 
 ODE_SOLVER    = 'null'
 ODE_REL_ERROR = -1._EB
@@ -4563,6 +4564,10 @@ SUBROUTINE READ_COMB
 IF (ODE_MIN_ATOL < 0.D0) ODE_MIN_ATOL = DBLE(0.1_EB*ZZ_MIN_GLOBAL)
 IF (ODE_REL_ERROR > 0._EB) GLOBAL_ODE_REL_ERROR = ODE_REL_ERROR
 
+! Set index for ZETA_0 ramp, if needed
+
+IF (RAMP_ZETA_0 /='null') CALL GET_RAMP_INDEX(RAMP_ZETA_0,'TIME',ZETA_0_RAMP_INDEX)
+
 END SUBROUTINE READ_COMB