Changeset 243 for trunk/eml

Timestamp:

Apr 16, 2007, 2:19:39 PM (16 years ago)

Author:

Paula Bettio Staudt

Message:

Updated reactive distillation models andsample

Location:

trunk/eml

Files:

• controllers/PIDs.mso (modified) (3 diffs)
• stage_separators/column.mso (modified) (2 diffs)
• stage_separators/condenser.mso (modified) (4 diffs)
• stage_separators/reboiler.mso (modified) (4 diffs)
• stage_separators/tray.mso (modified) (5 diffs)

trunk/eml/controllers/PIDs.mso

@@ -97 +97 @@
         if (Parameters.tau equal 0) then
                 "Input first order filter"
-                (Parameters.tau + 1e-3*"s")*diff(Internal.inputFilt)= Ports.input - Internal.inputFilt;
+                (Parameters.tau + 1e-3*'s')*diff(Internal.inputFilt)= Ports.input - Internal.inputFilt;
         else
                 "Input first order filter"
@@ -105 +105 @@
         if (Parameters.tauSet equal 0) then
                 "setPoint first order filter"
-                (Parameters.tauSet + 1e-3*"s")*diff(Internal.setPointFilt)= Ports.setPoint - Internal.setPointFilt;
+                (Parameters.tauSet + 1e-3*'s')*diff(Internal.setPointFilt)= Ports.setPoint - Internal.setPointFilt;
         else
                 "setPoint first order filter"
@@ -132 +132 @@
         if (Parameters.derivTime equal 0) then
                 "Derivative term filter"        
-                Parameters.alpha*(Parameters.derivTime + 1e-3*"s")*diff(Internal.dFilt) = Internal.errorD - Internal.dFilt;
+                Parameters.alpha*(Parameters.derivTime + 1e-3*'s')*diff(Internal.dFilt) = Internal.errorD - Internal.dFilt;
         else
                 "Derivative term filter"        

trunk/eml/stage_separators/column.mso

@@ -930 +930 @@
 Model ReactiveDistillation
         PARAMETERS
-        outer PP as Plugin(Brief = "External Physical Properties", Type="PP");
-        outer NComp as Integer;
-        NTrays as Integer(Brief="Number of trays", Default=2);
+        outer PP as Plugin(Type="PP");
+        outer NComp as Integer;
+        NTrays as Integer(Brief="Number of trays", Default=2);
+        topdown as Integer(Brief="Trays counting (1=top-down, -1=bottom-up)", Default=1);
+        top as Integer(Brief="Number of top tray");
+        bot as Integer(Brief="Number of bottom tray");
+        alfacond as Real;
+
+        VapourFlow as Switcher(Valid = ["on", "off"], Default = "off");
+        
+        SET
+        top = (NTrays-1)*(1-topdown)/2+1;
+        bot = NTrays/top;
         
         VARIABLES
@@ -942 +952 @@
         
         EQUATIONS
-        if ( reb.OutletV.P > 1 * 'atm' ) then
-                "Pressure Drop through the tray"
-                reb.OutletV.F = trays(1).Ah/reb.vV * sqrt((reb.OutletV.P - 1*'atm') / (0.15*reb.rhoV) );
-        else
+        
+        switch VapourFlow
+                case "on":
+                "Pressure Drop through the condenser"
+                cond.InletV.F*trays(top).vV / 'm^2' =
+                        sqrt((trays(top).OutletV.P - cond.OutletL.P + 1e-8 * 'atm')/(trays(top).rhoV*alfacond));
+                when trays(top).OutletV.P < cond.OutletL.P switchto "off";
+                
+                case "off":
                 "Prato selado"
-                reb.OutletV.F = 0.0 * 'mol/s';
+                cond.InletV.F = 0.0 * 'mol/s';
+                when trays(top).OutletV.P > cond.OutletL.P + 1e-3 * 'atm' switchto "on";
         end
-        
-        CONNECTIONS
-        #vapor
-        reb.OutletV to trays([NTrays]).InletV;
-        trays([2:NTrays]).OutletV to trays([1:NTrays-1]).InletV;
-        trays(1).OutletV to cond.InletV;
-
+
+        CONNECTIONS
+        #vapor
+        reb.OutletV to trays(bot).InletV;
+        trays([top+topdown:topdown:bot]).OutletV to trays([top:topdown:bot-topdown]).InletV;
+        trays(top).OutletV to cond.InletV;
+        
         #liquid
         cond.OutletL to sp.Inlet;       
         sp.Outlet2 to p.Inlet;
-        p.Outlet to trays(1).InletL;
-        trays([1:NTrays-1]).OutletL to trays([2:NTrays]).InletL;
-        trays(NTrays).OutletL to reb.InletL;
-end
+        p.Outlet to trays(top).InletL;
+        trays([top:topdown:bot-topdown]).OutletL to trays([top+topdown:topdown:bot]).InletL;
+        trays(bot).OutletL to reb.InletL;
+        
+end

trunk/eml/stage_separators/condenser.mso

@@ -135 +135 @@
 Model condenserReact
         PARAMETERS
-        outer PP as Plugin(Brief = "External Physical Properties", Type="PP");
+        outer PP as Plugin(Type="PP");
         outer NComp as Integer;
         V as volume (Brief="Condenser total volume");
@@ -158 +158 @@
         Q as heat_rate (Brief="Heat supplied");
         Vol as volume;
-        r as reaction_mol (Brief = "Specific reaction rate");
+        r3 as reaction_mol (Brief = "Reaction resulting ethyl acetate", DisplayUnit = 'mol/l/s');
         C(NComp) as conc_mol (Brief = "Molar concentration", Lower = -1);
 
@@ -165 +165 @@
         OutletL.z = vL * C;
         
+        "Reaction"
+        r3 = exp(-7150*'K'/OutletL.T)*(4.85e4*C(1)*C(2) - 1.23e4*C(3)*C(4)) * 'l/mol/s';
+        
         "Component Molar Balance"
         diff(M) = InletV.F*InletV.z - OutletL.F*OutletL.z
-                                - OutletV.F*OutletV.z + stoic*r*ML*vL;
+                                - OutletV.F*OutletV.z + stoic*r3*ML*vL;
 
         "Energy Balance"
         diff(E) = InletV.F*InletV.h - OutletL.F*OutletL.h
-                                - OutletV.F*OutletV.h + Q + Hr * r * ML*vL;
+                                - OutletV.F*OutletV.h + Q + Hr * r3 * ML*vL;
 
         "Molar Holdup"
@@ -206 +209 @@
 
         sum(OutletL.z)=sum(OutletV.z);
+
 end

trunk/eml/stage_separators/reboiler.mso

@@ -191 +191 @@
 Model reboilerReact
         PARAMETERS
-        outer PP as Plugin(Brief = "External Physical Properties", Type="PP");
+        outer PP as Plugin(Type="PP");
         outer NComp as Integer;
         Across as area (Brief="Cross Section Area of reboiler");
@@ -217 +217 @@
         startup as Real;
         rhoV as dens_mass;
-        r as reaction_mol (Brief = "Specific reaction rate");
+        r3 as reaction_mol (Brief = "Reaction resulting ethyl acetate", DisplayUnit = 'mol/l/s');
         C(NComp) as conc_mol (Brief = "Molar concentration", Lower = -1);
 
@@ -224 +224 @@
         OutletL.z = vL * C;
         
+        "Reaction"
+        r3 = exp(-7150*'K'/OutletL.T)*(4.85e4*C(1)*C(2) - 1.23e4*C(3)*C(4)) * 'l/mol/s';
+
         "Component Molar Balance"
         diff(M)= Inlet.F*Inlet.z + InletL.F*InletL.z
-                - OutletL.F*OutletL.z - OutletV.F*OutletV.z + stoic*r*ML*vL;
+                - OutletL.F*OutletL.z - OutletV.F*OutletV.z + stoic*r3*ML*vL;
         
         "Energy Balance"
         diff(E) = Inlet.F*Inlet.h + InletL.F*InletL.h
-                - OutletL.F*OutletL.h - OutletV.F*OutletV.h + Q + Hr * r * vL*ML;
+                - OutletL.F*OutletL.h - OutletV.F*OutletV.h + Q + Hr * r3 * vL*ML;
         
         "Molar Holdup"
@@ -260 +263 @@
         
         "Geometry Constraint"
-        V = ML*vL + MV*vV;
+        V = ML*vL + MV*vV;              
 
         "Chemical Equilibrium"

trunk/eml/stage_separators/tray.mso

@@ -159 +159 @@
 
         PARAMETERS
-        outer PP as Plugin(Brief = "External Physical Properties", Type="PP");
+        outer PP as Plugin(Type="PP");
         outer NComp as Integer;
         V as volume(Brief="Total Volume of the tray");
@@ -175 +175 @@
         Hr as energy_mol;
         Pstartup as pressure;
+        
+        VapourFlow as Switcher(Valid = ["on", "off"], Default = "off");
+        LiquidFlow as Switcher(Valid = ["on", "off"], Default = "off");
         
         VARIABLES
@@ -197 +200 @@
         rhoL as dens_mass;
         rhoV as dens_mass;
-        r as reaction_mol (Brief = "Specific reaction rate");
+        r3 as reaction_mol (Brief = "Reaction resulting ethyl acetate", DisplayUnit = 'mol/l/s');
         C(NComp) as conc_mol (Brief = "Molar concentration", Lower = -1); #, Unit = "mol/l");
         
@@ -204 +207 @@
         OutletL.z = vL * C;
         
+        "Reaction"
+        r3 = exp(-7150*'K'/OutletL.T)*(4.85e4*C(1)*C(2) - 1.23e4*C(3)*C(4))*'l/mol/s';
+        
         "Component Molar Balance"
         diff(M)=Inlet.F*Inlet.z + InletL.F*InletL.z + InletV.F*InletV.z
-                - OutletL.F*OutletL.z - OutletV.F*OutletV.z + stoic*r*ML*vL;
+                - OutletL.F*OutletL.z - OutletV.F*OutletV.z + stoic*r3*ML*vL;
         
         "Energy Balance"
         diff(E) = ( Inlet.F*Inlet.h + InletL.F*InletL.h + InletV.F*InletV.h
-                - OutletL.F*OutletL.h - OutletV.F*OutletV.h + Q ) + Hr * r * vL*ML;
+                - OutletL.F*OutletL.h - OutletV.F*OutletV.h + Q ) + Hr * r3 * vL*ML;
         
         "Molar Holdup"
@@ -242 +248 @@
         rhoV = PP.VapourDensity(InletV.T, InletV.P, InletV.z);
 
-        if Level > (beta * hw) then
+        switch LiquidFlow
+                case "on":
                 "Francis Equation"
-                OutletL.F = (1.84/'s'*lw*((Level-(beta*hw))/(beta))^2/vL);
-        else
+                OutletL.F*vL = 1.84*'1/s'*lw*((Level-(beta*hw)+1e-6*'m')/(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.P = OutletV.P + Level*g*rhoL + rhoV*alfa*(InletV.F*vV/Ah)^2;
+                InletV.F*vV = sqrt((InletV.P - OutletV.P - Level*g*rhoL + 1e-8 * 'atm')/(rhoV*alfa))*Ah;
+                when InletV.P < OutletV.P + Level*g*rhoL switchto "off";
                 
-        "Pressure Drop through the tray"
-        OutletV.F = (1 + tanh(1 * (OutletV.P - Pstartup)/'Pa'))/2 * 
-                Ah/vV * sqrt(2*(OutletV.P - InletL.P + 1e-8 * 'atm') / (alfa*rhoV) );
+                case "off":
+                InletV.F = 0 * 'mol/s';
+                when InletV.P > OutletV.P + Level*g*rhoL + 3e-2 * 'atm' switchto "on";
+                #when InletV.P > OutletV.P + Level*beta*g*rhoL + 1e-2 * 'atm' switchto "on";
+        end
 
         "Chemical Equilibrium"