subroutine JetImpactForce

    use sROP_Other_Variables
    use sROP_Variables
    use CStringConfigurationVariables
    use CformationVariables
    ! use CSimulationVariables
    use CmudPropertiesVariables
    USE MudSystemVARIABLES
use SimulationVariables !@@@
    
    implicit none
    
    Real(8) :: DeltaPb , NozzleTotalArea , Cd=0.95d0
    
    
    
    
    data%State%ROP_Bit%BitFlowrate    = data%State%MudSystem%StringFlowRateFinal      ![gpm]
    !if(print_log) print*, 'data%State%ROP_Bit%BitFlowrate=' , data%State%ROP_Bit%BitFlowrate
    !check :: data%State%ROP_Bit%MudDensity [ppg]   ??????????
    
    NozzleTotalArea = data%State%ROP_Spec%NumberOfBitNozzles*(data%State%ROP_Spec%DiameterOfBitNozzle**2)*(PI/4.d0)
    
    DeltaPb         = (8.311d-5*data%State%ROP_Bit%MudDensity*(data%State%ROP_Bit%BitFlowrate**2))/((Cd**2)*(NozzleTotalArea**2))
    
    data%State%ROP_Bit%JetImpactForce = 0.01823d0*Cd*data%State%ROP_Bit%BitFlowrate*sqrt(data%State%ROP_Bit%MudDensity*DeltaPb)
    
    
    
    
end subroutine