Fix logic error in AirDens handling in FAST_Subs

ExtInfw was incorrectly receiving a 0 for the air density due to a logic error introduced when ExtInfw_Init was relocated to after AeroDyn

Also add AirDens initialization output from AeroDisk (this gets passed to ServoDyn)

modules/aerodisk/src/AeroDisk.f90

@@ -261,7 +261,8 @@ subroutine Init_InitY(ErrStat3,ErrMsg3)
          InitOut%WriteOutputUnt(i) = p%OutParam(i)%Units
       end do
       ! Version
-      InitOut%Ver = ADsk_Ver
+      InitOut%Ver     = ADsk_Ver
+      InitOut%AirDens = p%AirDens
    end subroutine Init_InitY
 END SUBROUTINE ADsk_Init
 

modules/aerodisk/src/AeroDisk_Registry.txt

@@ -65,6 +65,7 @@ typedef  ^        InitInputType     FlowFieldType        *FlowField        -  -
 typedef  ^        InitOutputType    CHARACTER(ChanLen)   WriteOutputHdr   {:} - -   "Names of the output-to-file channels"   -
 typedef  ^        InitOutputType    CHARACTER(ChanLen)   WriteOutputUnt   {:} - -   "Units of the output-to-file channels"   -
 typedef  ^        InitOutputType    ProgDesc             Ver               -  - -   "This module's name, version, and date"   -
+typedef  ^        InitOutputType    ReKi                 AirDens           -  - -   "Air density" "kg/m^3"
 
 
 # ..... Inputs ....................................................................................................................

modules/aerodisk/src/AeroDisk_Types.f90

@@ -86,6 +86,7 @@ MODULE AeroDisk_Types
     CHARACTER(ChanLen) , DIMENSION(:), ALLOCATABLE  :: WriteOutputHdr      !< Names of the output-to-file channels [-]
     CHARACTER(ChanLen) , DIMENSION(:), ALLOCATABLE  :: WriteOutputUnt      !< Units of the output-to-file channels [-]
     TYPE(ProgDesc)  :: Ver      !< This module's name, version, and date [-]
+    REAL(ReKi)  :: AirDens = 0.0_ReKi      !< Air density [kg/m^3]
   END TYPE ADsk_InitOutputType
 ! =======================
 ! =========  ADsk_InputType  =======
@@ -634,6 +635,7 @@ subroutine ADsk_CopyInitOutput(SrcInitOutputData, DstInitOutputData, CtrlCode, E
    call NWTC_Library_CopyProgDesc(SrcInitOutputData%Ver, DstInitOutputData%Ver, CtrlCode, ErrStat2, ErrMsg2)
    call SetErrStat(ErrStat2, ErrMsg2, ErrStat, ErrMsg, RoutineName)
    if (ErrStat >= AbortErrLev) return
+   DstInitOutputData%AirDens = SrcInitOutputData%AirDens
 end subroutine
 
 subroutine ADsk_DestroyInitOutput(InitOutputData, ErrStat, ErrMsg)
@@ -663,6 +665,7 @@ subroutine ADsk_PackInitOutput(RF, Indata)
    call RegPackAlloc(RF, InData%WriteOutputHdr)
    call RegPackAlloc(RF, InData%WriteOutputUnt)
    call NWTC_Library_PackProgDesc(RF, InData%Ver) 
+   call RegPack(RF, InData%AirDens)
    if (RegCheckErr(RF, RoutineName)) return
 end subroutine
 
@@ -677,6 +680,7 @@ subroutine ADsk_UnPackInitOutput(RF, OutData)
    call RegUnpackAlloc(RF, OutData%WriteOutputHdr); if (RegCheckErr(RF, RoutineName)) return
    call RegUnpackAlloc(RF, OutData%WriteOutputUnt); if (RegCheckErr(RF, RoutineName)) return
    call NWTC_Library_UnpackProgDesc(RF, OutData%Ver) ! Ver 
+   call RegUnpack(RF, OutData%AirDens); if (RegCheckErr(RF, RoutineName)) return
 end subroutine
 
 subroutine ADsk_CopyInput(SrcInputData, DstInputData, CtrlCode, ErrStat, ErrMsg)

modules/openfast-library/src/FAST_Subs.f90

@@ -766,6 +766,7 @@ SUBROUTINE FAST_InitializeAll( t_initial, p_FAST, y_FAST, m_FAST, ED, SED, BD, S
          RETURN
       END IF
 
+      ! AeroDyn may override the AirDens value.  Store this to inform other modules
       AirDens = Init%OutData_AD%rotors(1)%AirDens
 
    ELSEIF ( p_FAST%CompAero == Module_ADsk ) THEN
@@ -795,6 +796,9 @@ SUBROUTINE FAST_InitializeAll( t_initial, p_FAST, y_FAST, m_FAST, ED, SED, BD, S
       CALL SetModuleSubstepTime(Module_ADsk, p_FAST, y_FAST, ErrStat2, ErrMsg2)
          CALL SetErrStat(ErrStat2,ErrMsg2,ErrStat,ErrMsg,RoutineName)
 
+      ! AeroDisk may override the AirDens value.  Store this to inform other modules
+      AirDens = Init%OutData_ADsk%AirDens
+
    END IF ! CompAero
 
    IF ( p_FAST%CompAero == Module_ExtLd ) THEN
@@ -815,6 +819,7 @@ SUBROUTINE FAST_InitializeAll( t_initial, p_FAST, y_FAST, m_FAST, ED, SED, BD, S
             RETURN
          END IF
 
+         ! ExtLd may override the AirDens value.  Store this to inform other modules
          AirDens = Init%OutData_ExtLd%AirDens
 
       END IF
@@ -824,8 +829,7 @@ SUBROUTINE FAST_InitializeAll( t_initial, p_FAST, y_FAST, m_FAST, ED, SED, BD, S
    ! ........................
    ! No aero of any sort
    ! ........................
-   IF ( (p_FAST%CompAero /= Module_AD) .and. (p_FAST%CompAero /= Module_ExtLd) ) THEN
-   ELSE
+   IF ( (p_FAST%CompAero == Module_None) .or. (p_FAST%CompAero == Module_ExtInfw)) THEN
       AirDens = 0.0_ReKi
    ENDIF