Merge pull request #14745 from ericvmueller/master

FDS Source: tweak experimental ember snag model so embers can catch o…

Author: ericvmueller

Source/part.f90

@@ -2710,12 +2710,11 @@ SUBROUTINE MOVE_IN_GAS
    ! experimental ember snag model
    IF (LP%EMBER .AND. LPC%EMBER_SNAG_FACTOR>0._EB) THEN
       STUCK=.FALSE.
-      ! constrain max packing ratio to 1
-      EMBER_PACKING_RATIO = MIN(1._EB, EMBER_VOLUME * LP%PWT * LP%RVC)
+      ! constrain packing ratio between 0 and 1
+      EMBER_PACKING_RATIO = MAX(MIN(1._EB, EMBER_VOLUME * LP%PWT * LP%RVC),0._EB)
       LOCAL_PACKING_RATIO = 0._EB
       LPC2_LOOP: DO N_LPC2=1,N_LAGRANGIAN_CLASSES
          LPC2 => LAGRANGIAN_PARTICLE_CLASS(N_LPC2)
-         IF (LPC2%ARRAY_INDEX == LPC%ARRAY_INDEX) CYCLE LPC2_LOOP
          IF (AVG_DROP_RAD(IIG_OLD,JJG_OLD,KKG_OLD,LPC2%ARRAY_INDEX)<TWO_EPSILON_EB) CYCLE LPC2_LOOP
          SELECT CASE(SURFACE(LPC2%SURF_INDEX)%GEOMETRY)
             CASE(SURF_CARTESIAN)
@@ -2728,7 +2727,8 @@ SUBROUTINE MOVE_IN_GAS
          LOCAL_PACKING_RATIO = LOCAL_PACKING_RATIO + AVG_DROP_AREA(IIG_OLD,JJG_OLD,KKG_OLD,LPC2%ARRAY_INDEX)*&
                   AVG_DROP_RAD(IIG_OLD,JJG_OLD,KKG_OLD,LPC2%ARRAY_INDEX)*LPC_GEOM_FACTOR
       ENDDO LPC2_LOOP
-      LOCAL_PACKING_RATIO = MIN(1._EB, LOCAL_PACKING_RATIO)
+      LOCAL_PACKING_RATIO = LOCAL_PACKING_RATIO - EMBER_PACKING_RATIO
+      LOCAL_PACKING_RATIO = MAX(MIN(1._EB, LOCAL_PACKING_RATIO),0._EB)
       CALL RANDOM_NUMBER(RN)
       IF (LOCAL_PACKING_RATIO>TWO_EPSILON_EB .AND. &
          RN<(LOCAL_PACKING_RATIO*EMBER_PACKING_RATIO)**LPC%EMBER_SNAG_FACTOR) THEN