Changeset 517 for branches/rate/eml/stage_separators/tray.mso

Timestamp:

May 19, 2008, 11:29:24 AM (15 years ago)

Author:

Argimiro Resende Secchi

Message:

Updating tray rate model.

File:

• branches/rate/eml/stage_separators/tray.mso (modified) (6 diffs)

branches/rate/eml/stage_separators/tray.mso

@@ -119 +119 @@
 == Initial ==
 * the plate temperature (OutletL.T)
-* the liquid height (Level) OR the liquid flow OutletL.F
+* the liquid height (Level) OR the liquid holdup (ML)
 * (NoComps - 1) OutletL compositions
 ";      
@@ -494 +494 @@
         
         VARIABLES
-        NL(NComp) as flow_mol   (Brief = "Stream Molar Rate on Liquid Phase");
-        NV(NComp) as flow_mol   (Brief = "Stream Molar Rate on Vapour Phase");
+        NL(NComp) as flow_mol_delta     (Brief = "Stream Molar Rate on Liquid Phase");
+        NV(NComp) as flow_mol_delta     (Brief = "Stream Molar Rate on Vapour Phase");
         T as temperature                (Brief = "Stream Temperature");
         P as pressure                   (Brief = "Stream Pressure");
@@ -519 +519 @@
 end
 
-Model trayRate 
+Model trayRateBasic
         ATTRIBUTES
         Pallete         = false;
         Icon            = "icon/Tray"; 
-        Brief           = "Basic equations of a tray column model.";
+        Brief           = "Basic equations of a tray rate column model.";
         Info            =
 "This model contains only the main equations of a column tray nonequilibrium model without
@@ -561 +561 @@
         Level as length (Brief="Height of clear liquid on plate");
         interf as interface;    
-        
+
+        SET   
+        NC1=NComp-1;
+
         EQUATIONS
         "Component Molar Balance"
@@ -622 +625 @@
         interf.NL(1:NC1)=interf.a*sumt(interf.kL*(interf.x(1:NC1)-OutletL.z(1:NC1)))/vL+
                 OutletL.z(1:NC1)*sum(interf.NL);
+
+#       interf.NL(1:NC1)=0.01*'kmol/s';
         
         interf.NV(1:NC1)=interf.a*sumt(interf.kV*(OutletV.z(1:NC1)-interf.y(1:NC1)))/vV+
@@ -629 +634 @@
         OutletV.P = OutletL.P;
         interf.P=OutletL.P;
-        
-        SET   
-        NC1=NComp-1;
 end
 
+Model trayRate as trayRateBasic
+        ATTRIBUTES
+        Pallete         = false;
+        Icon            = "icon/Tray"; 
+        Brief           = "Complete rate model of a column tray.";
+        Info            =
+"== Specify ==
+* the Feed stream
+* the Liquid inlet stream
+* the Vapour inlet stream
+* the Vapour outlet flow (OutletV.F)
+        
+== Initial ==
+* the plate temperature of both phases (OutletL.T and OutletV.T)
+* the liquid height (Level) OR the liquid flow holdup (ML)
+* the vapor holdup (MV)
+* (NoComps - 1) OutletL compositions
+";
+
+        PARAMETERS
+        Ah as area (Brief="Total holes area");
+        lw as length (Brief="Weir length");
+        g as acceleration (Default=9.81);
+        hw as length (Brief="Weir height");
+        beta as fraction (Brief="Aeration fraction");
+        alfa as fraction (Brief="Dry pressure drop coefficient");
+        
+        VapourFlow as Switcher(Valid = ["on", "off"], Default = "on");
+        LiquidFlow as Switcher(Valid = ["on", "off"], Default = "on");
+        
+        VARIABLES
+        rhoL as dens_mass;
+        rhoV as dens_mass;
+
+        EQUATIONS
+        "Liquid Density"
+        rhoL = PP.LiquidDensity(OutletL.T, OutletL.P, OutletL.z);
+        "Vapour Density"
+        rhoV = PP.VapourDensity(InletV.T, InletV.P, InletV.z);
+
+        switch LiquidFlow
+                case "on":
+                "Francis Equation"
+#               OutletL.F*vL = 1.84*'m^0.5/s'*lw*((Level-(beta*hw))/(beta))^1.5;
+                OutletL.F*vL = 1.84*'1/s'*lw*((Level-(beta*hw))/(beta))^2;
+                when Level < (beta * hw) switchto "off";
+                
+                case "off":
+                "Low level"
+                OutletL.F = 0 * 'mol/h';
+                when Level > (beta * hw) + 1e-6*'m' switchto "on";
+        end
+
+        switch VapourFlow
+                case "on":
+                InletV.F*vV = sqrt((InletV.P - OutletV.P)/(rhoV*alfa))*Ah;
+                when InletV.F < 1e-6 * 'kmol/h' switchto "off";
+                
+                case "off":
+                InletV.F = 0 * 'mol/s';
+                when InletV.P > OutletV.P + Level*g*rhoL + 1e-1 * 'atm' switchto "on";
+        end     
+end