subroutine TD_MainCalculations
    
    Use CCasingLinerChokeVariables
    Use CStringConfigurationVariables
    ! use CSimulationVariables
    Use TD_DrillStemComponents
    Use TD_WellElements
    Use TD_WellGeometry
    Use TD_GeneralData
    Use TD_StringConnectionData
    Use FricPressDropVars
    Use MudSystemVARIABLES
    
    
    implicit none
    
    Integer              :: i
    !Integer              :: TD_SolDuration
    !integer,dimension(8) :: TD_StartTime , TD_EndTime
    
    
    
    TD_TimeStep = 0.1d0     ! Unit: [s]
    !Call TD_StartUp
    !Call TD_WellReadData
    !Call TD_WellElementsReadData
    !Call TD_DrillStemReadData
    !Call TD_PipePropertiesReadData
    !!Call TD_WellGeoConfiguration
    !!Call TD_WellElementsConfiguration
    !!Call TD_StringConnectionModes
    !!Call TD_DrillStemConfiguration
    
    
    
    
    !loop1: do
    
    
        !CALL DATE_AND_TIME(values=TD_StartTime)
    
    
        Call TD_WellGeoConfiguration
        Call TD_WellElementsConfiguration
        Call TD_StringConnectionModes
        Call TD_DrillStemConfiguration
        Call TD_ForceReadData
        
        
!===> Mud properties Read_Data from Fluid Module
        !!TD_NoHorizontalMudElements = TDNoHorizontalMudElements
        !!TD_NoStringMudElements     = TDNoStringMudElements
        !!TD_NoCasingMudElements     = TDNoCasingMudElements
        !!
        !!if (allocated(TDDensity_MudElementArray) .and. (TD_NoHorizontalMudElements+TD_NoStringMudElements+TD_NoCasingMudElements)/=0) then
        !!    if (Allocated(TD_FluidMudDensity))  Deallocate(TD_FluidMudDensity)
        !!    Allocate(TD_FluidMudDensity(TD_NoHorizontalMudElements+TD_NoStringMudElements+TD_NoCasingMudElements))
        !!    TD_FluidMudDensity(:) = TDDensity_MudElementArray(:)
        !!end if
        !!
        !!if (allocated(TDXend_MudElementArray)) then
        !!    if (Allocated(TD_FluidMudEndX))  Deallocate(TD_FluidMudEndX)
        !!    Allocate(TD_FluidMudEndX(TD_NoHorizontalMudElements+TD_NoStringMudElements+TD_NoCasingMudElements))
        !!    TD_FluidMudEndX(:) = TDXend_MudElementArray(:)
        !!end if
        !!
        !!if (allocated(TDXstart_MudElementArray)) then
        !!    if (Allocated(TD_FluidMudStartX))  Deallocate(TD_FluidMudStartX)
        !!    Allocate(TD_FluidMudStartX(TD_NoHorizontalMudElements+TD_NoStringMudElements+TD_NoCasingMudElements))
        !!    TD_FluidMudStartX(:) = TDXstart_MudElementArray(:)
        !!end if
        
        if (TD_DrillStem(1)%ComponentType==0) then
            Do i = 2 , TD_DrillStemComponentsNumbs
                Call TD_MudPropertiesReadData(i)
                Call TD_BouyancyFactor(i)
                Call TD_CombinedMotionData(i)
            End Do
            TD_DrillStems(1)%MudDensityIn  = TD_DrillStems(2)%MudDensityIn  !(1): bit mud properties
            TD_DrillStems(1)%MudDensityOut = TD_DrillStems(2)%MudDensityOut
            TD_DrillStems(1)%MudWeight     = TD_DrillStems(2)%MudWeight
            TD_DrillStems(1)%MudPlasticVis = 5.d0+(5.d0*(TD_DrillStems(1)%MudWeight-8.3d0))
            TD_DrillStems(1)%MudViscosity  = 0.2d0                          !TD_DrillStems(i)%MudPlasticVis
            TD_DrillStems(1)%MudYieldPoint = 10.d0+(TD_DrillStems(1)%MudWeight-8.3d0)
            Call TD_BouyancyFactor(1)
            Call TD_CombinedMotionData(1)
        else
            Do i = 1 , TD_DrillStemComponentsNumbs
                Call TD_MudPropertiesReadData(i)
                Call TD_BouyancyFactor(i)
                Call TD_CombinedMotionData(i)
            End Do
        end if
!================================================
      
        
        
        Call TD_BOPDiamCalculation
    
    
        Call TD_StaticHookLoadCalculation
        Call TD_WeightOnBitCalculation
        if (abs(TD_DrillStemAxialVelocity)>3.2808d0) then   !1[m/s]=3.2808[ft/s]
            Call TD_ViscousDragForce
        else
            TD_DrillStems%Drag    = 0.d0
            TD_DrillStemForceType = 5
        end if
        Call TD_ForceCalculation
        Call TD_HookLoadCalculation
    
    
    
            !!!!!!print*, 'TD_StringVelocity='   , TD_StringVelocity
            !!!!!!print*, 'TD_HookLoad='   , TD_HookLoad
            !print*, 'TD_WellTotalLength=' , TD_WellTotalLength
            !print*, 'TD_ConnectionHeight_main='  , TD_ConnectionHeight
            !!!!!!!!print*, 'TD_DrillStems(1)%StartAngle='      , TD_DrillStems(1)%StartAngle
            !!!!!!print*, 'TD_DrillStems(1)%Force2='   , TD_DrillStems(1)%Force2
            !!!!!!print*, 'TD_DrillStems(1)%Force1='   , TD_DrillStems(1)%Force1
            !!!!!print*, 'TD_WeightIndicator='   , TD_WeightIndicator
            !!!!!print*, 'TD_DlTotal='   , TD_DlTotal
            !!!!!print*, 'TD_DlMax='   , TD_DlMax
            !!!!!!print*, 'TD_DrillStems(n)%Force2='   , TD_DrillStems(TD_DrillStemComponentsNumbs)%Force2
            !!!!!!print*, 'TD_DrillStems(n)%Force1='   , TD_DrillStems(TD_DrillStemComponentsNumbs)%Force1
            !print*, 'TD_DrillStems(1)%Drag='   , TD_DrillStems(1)%Drag
            !!!!!!!!!
            !print*, 'TD_WeightOnBit='   , TD_WeightOnBit
            !!print*, 'TD_StringTorque='   , TD_StringTorque
            !!print*, 'TD_DrillStems(1)%Torque='   , TD_DrillStems(1)%Torque
            !!print*, 'TD_DrillStems(n)%Torque='   , TD_DrillStems(TD_DrillStemComponentsNumbs)%Torque
            !!!!!!!!!
            !print*, 'TD_DrillStemComponentsNumbs_main ='    ,TD_DrillStemComponentsNumbs 
            !print*, 'TD_DrillStemTotalLength='    ,TD_DrillStemTotalLength
            !!print*, 'TD_StringConfigurationCount='     ,TD_StringConfigurationCount
            !print*, 'TD_HookHeight='     ,TD_HookHeight
            !!!!!!print*, 'TD_HookVelocity='     ,TD_HookVelocity
            !print*, 'TD_DrillStems(1)%DownDepth='     ,TD_DrillStems(1)%DownDepth
            !print*, 'TD_DrillStems(1)%DownDepthIni_main='     ,TD_DrillStems(1)%DownDepthIni
            !!!!!!print*, 'TD_DrillStems(1)%DownDepth='     ,TD_DrillStems(335)%DownDepth
            !!print*, 'TD_DrillStems(n)%DownDepth='     ,TD_DrillStems(TD_DrillStemComponentsNumbs)%DownDepth
            !!!print*, 'TD_DrillStems(n)%ID='     ,TD_DrillStems(TD_DrillStemComponentsNumbs)%ID
            !!!print*, 'TD_DrillStems(n)%OD='     ,TD_DrillStems(TD_DrillStemComponentsNumbs)%OD
            !!!print*, 'TD_DrillStem(n)%ID='     ,TD_DrillStem(TD_StringConfigurationCount)%ID
            !!!print*, 'TD_DrillStem(n)%OD='     ,TD_DrillStem(TD_StringConfigurationCount)%OD
            !!!print*, 'TD_DrillStem(1)%ID='     ,TD_DrillStem(1)%ID
            !!!print*, 'TD_DrillStem(1)%OD='     ,TD_DrillStem(1)%OD
            !!!!!print*, 'TD_StaticHookLoad='     ,TD_StaticHookLoad
            !!!!print*, 'TD_DrillStems(n)%Dl='     ,TD_DrillStems(TD_DrillStemComponentsNumbs)%Dl
            !!!!!print*, 'TD_DrillStems(n)%Length='     ,TD_DrillStems(TD_DrillStemComponentsNumbs)%Length
            !!!!!print*, 'TD_DrillStem(1)%Length='     ,TD_DrillStem(1)%Length
            !!!!!print*, 'TD_DrillStems(n)%Area='     ,TD_DrillStems(TD_DrillStemComponentsNumbs)%Area
            !!!!!print*, 'TD_DrillStems(n)%ElasticModule='     ,TD_DrillStems(TD_DrillStemComponentsNumbs)%ElasticModule
        
        TD_HookHeightOld = TD_HookHeight
    
    
    !    if(IsStopped == .true.) then
    !        EXIT loop1
    !    end if
    ! 
    !    
    !    CALL DATE_AND_TIME(values=TD_EndTime)
    !    TD_SolDuration=100-(TD_EndTime(6)*60000+TD_EndTime(7)*1000+TD_EndTime(8)-TD_StartTime(6)*60000-TD_StartTime(7)*1000-TD_StartTime(8))
    !    !print*, 'TD_SolDuration=' , TD_SolDuration
    !    !print*, 'TD_exe='   , (TD_EndTime(6)*60000+TD_EndTime(7)*1000+TD_EndTime(8)-TD_StartTime(6)*60000-TD_StartTime(7)*1000-TD_StartTime(8))
    !    if(TD_SolDuration > 0.0d0) then
    !       CALL sleepqq(TD_SolDuration)
    !    end if
    !
    !    
    !end do loop1
    !
    !return
    
    
    
    
    
end subroutine TD_MainCalculations