Transport Processes in a 1D System Case of a River

What is a river? 'grid definition Type grid 'Channel Length Length As Double 'Channel cross Section AreaVertical As Double waterdepth As Double 'Channel Horizontal Surface width As Double HorizontalArea As Double 'number of cells NC As Integer ‘cells length (spatial step) dx As Double 'distance of cell center to origin xc() As Double End Type

How to describe the Flow in a River Type Flow_properties Velocity As Double Discharge As Double Diffusivity As Double FourierNr As Double DiffusionNr As Double CourantNr As Double End Type In a real river the flow changes along the river. In this course we are going to consider a schematic river where the flow is uniform along the river.

Control Parameters Type Controls t As Double TimeDays As Double dt As Double tstart As Double tend As Double printtime As Double Printnumber As Double NumberOfOutputs As Integer DtPrint As Double PrintLine As Integer FirstPrintLine As Long FirstOutput As Boolean Advection As Boolean Diffusion As Boolean AdvType As String Explicit As Boolean End Type Control Parameters

Boundary Conditions Type Discharge_properties Type BoundaryCondition LeftType As Integer LeftValue As Double   RightType As Integer RightValue As Double PropDischarges As Discharges End Type Type Discharge_properties Number As Integer Name As String Cell As Integer VolumeRate As Double SpecificValue As Double End Type Type Discharges NumberOfDischarges As Integer Discharge() As Discharge_properties End Type

A Property Type Property Old() As Double NewValue() As Double   Default As Double minimum As Double maximum As Double MinimumActive As Boolean MaximumActive As Boolean RatioToC As Double RatioToPlot As Double DecayRate As Double GrowthRate As Double GrazingRate As Double GrazingEff As Double GrazingKsat As Double ExcretionRate As Double   TminToGrow As Double TmaxToGrow As Double ToptToGrow As Double LminToGrow As Double LmaxToGrow As Double LoptToGrow As Doub Boundary As BoundaryCondition SheetName As String Calc_As As PropCalcMethod InitCell As Integer End Type Type PropCalcMethod Method As String Imposed_TimeSeries() As Double N_Instants As Double N_interval As Integer SinusAmplitude As Double SinusPhaseVel As Double SinusPhase As Double SinusAverage As Double End Type

Properties Type Properties ' Prey As Property ' Predator As Property ' Detritus As Property Temperature As Property Generic As Property ' Nutrient As Property End Type

Equations Type Equation_Coef Left2Coef() As Double Ci Ci-1 Ci+1 Type Equation_Coef Left2Coef() As Double LeftCoef() As Double CenterCoef() As Double RigthCoef() As Double Rigth2Coef() As Double TiCoef() As Double End Type

Atmosphere Type Atmosphere Atm_Temp_Default As Double Atm_Humidity_Default As Double Atm_Radiation_Default As Double Atm_Wind_Default As Double Sky_Temp_Default As Double   Atm_Temperature () As Double Atm_Humidity () As Double Atm_Radiation () As Double Atm_Wind () As Double Sky_Temp () As Double  Calc_As As PropCalcMethod End Type