Changeset 604 for branches

Timestamp:

Aug 21, 2008, 11:30:04 PM (14 years ago)

Author:

gerson bicca

Message:

added expander model

Location:

branches/gui

Files:

• eml/pressure_changers/turbine.mso (modified) (2 diffs)
• sample/pressure_changers/sample_expander.pfd (added)

branches/gui/eml/pressure_changers/turbine.mso

@@ -128 +128 @@
 Model expander
         
-        ATTRIBUTES
+ATTRIBUTES
         Pallete         = true;
         Icon            = "icon/HidraulicTurbine"; 
-        Brief           = "Testing Model of a expander.";
+        Brief           = "Model of an expansor.";
+        Info            =
+"To be documented";
         
 PARAMETERS
 
-outer NComp     as Integer                      (Brief = "Number of chemical components", Lower = 1);
-outer PP                as Plugin                       (Brief = "External Physical Properties", Type="PP");
-        Mw(NComp)       as molweight            (Brief = "Molar Weight");
-        
+outer PP                as Plugin               (Brief = "External Physical Properties", Type="PP");
+outer NComp     as Integer              (Brief = "Number of chemical components", Lower = 1);
+        Rgas            as positive     (Brief = "Constant of Gases", Unit= 'kJ/kmol/K', Default = 8.31451,Hidden=true);
+        Mw(NComp)       as molweight    (Brief = "Molar Weight");
+
 VARIABLES
-        Eff     as efficiency           (Brief = "Turbine efficiency");
-        Meff    as efficiency           (Brief = "Brake efficiency");
-        Beta    as positive             (Brief = "Volumetric expansivity", Unit = '1/K');
-        Head    as head                         (Brief = "Head Developed");
-        FPower  as power                        (Brief = "Fluid Power");
-        BPower  as power                        (Brief = "Brake Power");
-        Pratio  as positive                     (Brief = "Pressure Ratio");
-        Pdrop   as press_delta          (Brief = "Pressure Drop", DisplayUnit = 'kPa', Symbol ="\Delta P");
-        Mwm     as molweight            (Brief = "Mixture Molar Weight");
-        rho             as dens_mass            (Brief = "Specific Mass");
-        Cp              as cp_mol                       (Brief = "Heat Capacity");
-        
+
+        IseCoeff        as positive     (Brief = "Isentropic Coefficient", Lower=0.2); 
+        Pratio          as positive             (Brief = "Pressure Ratio", Symbol ="P_{ratio}");        
+        Pdrop           as press_delta  (Brief = "Pressure Drop", DisplayUnit = 'kPa', Symbol ="\Delta P");
+        Pdecrease       as press_delta  (Brief = "Pressure Decrease", DisplayUnit = 'kPa', Symbol ="P_{decr}");
+
+        Head                            as energy_mass  (Brief = "Head");
+        HeadIsentropic          as energy_mass  (Brief = "Isentropic Head");
+        Tisentropic                     as temperature  (Brief = "Isentropic Temperature"); 
+        
+        IsentropicEff   as efficiency   (Brief = "Isentropic efficiency");
+        MechanicalEff   as efficiency   (Brief = "Mechanical efficiency");
+        
+        FluidPower      as power                (Brief = "Fluid Power");
+        BrakePower      as power                (Brief = "Brake Power");
+        PowerLoss       as power                (Brief = "Power Losses");
+        Mwm                     as molweight    (Brief = "Mixture Molar Weight");
+        rho                     as dens_mass    (Brief = "Mass Density");
+        Zfac_in         as fraction     (Brief = "Compressibility factor at inlet");
+        Zfac_out        as fraction     (Brief = "Compressibility factor at outlet");
+
 in      Inlet           as stream       (Brief = "Inlet stream", PosX=0.05, PosY=0.0, Symbol="_{in}");
-out     Outlet          as stream       (Brief = "Outlet stream", PosX=0.65, PosY=1, Symbol="_{out}");
-out WorkOut             as power        (Brief = "Work Outlet", PosX=1, PosY=0.46);
+out     Outlet          as streamPH     (Brief = "Outlet stream", PosX=0.65, PosY=1, Symbol="_{out}");
+
+out     WorkOut         as power        (Brief = "Work Outlet", PosX=1, PosY=0.46);
 
 SET
-        Mw = PP.MolecularWeight();      
-        
+
+        Mw = PP.MolecularWeight();
+
+        Rgas    = 8.31451*'kJ/kmol/K';
+
 EQUATIONS
 
-"Calculate Mwm for Inlet Mixture"
+"Overall Molar Balance"
+        Outlet.F = Inlet.F;
+
+"Component Molar Balance"
+        Outlet.z = Inlet.z;
+
+"Average Molecular Weight"
         Mwm = sum(Mw*Inlet.z);
 
-"Calculate rho using a External Physical Properties Routine"
-        rho = PP.LiquidDensity(Inlet.T,Inlet.P,Inlet.z);
-        
-"Calculate Outlet Vapour Fraction"
-        Outlet.v = PP.VapourFraction(Outlet.T, Outlet.P, Outlet.z);
-        
-"Calculate Cp Using a External Physical Properties Routine"
-        Cp = PP.LiquidCp(Inlet.T,Inlet.P,Inlet.z);
-        
 "Pressure Ratio"
         Outlet.P = Inlet.P * Pratio;
@@ -179 +192 @@
         Outlet.P  = Inlet.P - Pdrop;
 
-"Calculate Fluid Power"
-        FPower * rho = -Pdrop * Inlet.F * Mwm;
-
-"Calculate Brake Power"
-        BPower = FPower * Eff;
-
-        BPower = WorkOut;
-
-"Calculate Outlet Temperature"
-        (Outlet.T - Inlet.T) * rho * Cp = (Outlet.h - Inlet.h) * rho
-        + Pdrop * Mwm * (1-Beta*Inlet.T);
-
-"Calculate Outlet Enthalpy"
-        (Outlet.h - Inlet.h) * rho =  -Pdrop * Mwm;
-
-"Molar Balance"
-        Outlet.F = Inlet.F;
-"Outlet Composition"
-        Outlet.z = Inlet.z;
-
-"Calculate Head"
-        Head = Outlet.h - Inlet.h;
-
-end
+"Pressure Decrease"
+        Outlet.P  = Inlet.P - Pdecrease;
+
+"Mass Density"
+        rho = PP.VapourDensity(Inlet.T, Inlet.P, Inlet.z);
+        
+"Compressibility factor at Inlet Conditions"
+        Zfac_in = PP.VapourCompressibilityFactor(Inlet.T,Inlet.P,Inlet.z);
+        
+"Compressibility factor at Outlet Conditions"
+        Zfac_out = PP.VapourCompressibilityFactor(Outlet.T,Outlet.P,Outlet.z);
+
+"Isentropic Head"
+        HeadIsentropic*Mwm = (PP.VapourEnthalpy(Tisentropic,Outlet.P,Outlet.z)-Inlet.h);
+
+"Isentropic Outlet Temperature"
+        PP.VapourEntropy(Tisentropic, Outlet.P, Outlet.z) = PP.VapourEntropy(Inlet.T, Inlet.P, Inlet.z);
+
+
+if IsentropicEff equal 1
+
+        then
+"Discharge Temperature"
+        Outlet.T = Tisentropic;
+
+"Head"
+        Head = HeadIsentropic;
+
+"Isentropic Coefficient"
+        IseCoeff= 1;
+
+        else
+"Isentropic Coefficient"
+        #HeadIsentropic = (0.5*Zfac_in+0.5*Zfac_out)*(1/Mwm)*(IseCoeff/(IseCoeff-1.001))*Rgas*Inlet.T*((Outlet.P/Inlet.P)^((IseCoeff-1.001)/IseCoeff) - 1);
+        Head = (0.5*Zfac_in+0.5*Zfac_out)*(1/Mwm)*(IseCoeff/(IseCoeff-1.001))*Rgas*Inlet.T*((Outlet.P/Inlet.P)^((IseCoeff-1.001)/IseCoeff) - 1);
+
+"Discharge Temperature"
+        Outlet.T = Inlet.T*((Outlet.P/Inlet.P)^((IseCoeff-1.001)/IseCoeff));
+
+"Head"
+        Head*Mwm = (PP.VapourEnthalpy(Outlet.T,Outlet.P,Outlet.z)-Inlet.h);
+
+end
+
+"Fluid Power"
+        FluidPower*IsentropicEff = Head*sum(Mw*Inlet.z)*Inlet.F;
+        #FluidPower = Head*sum(Mw*Inlet.z)*Inlet.F;
+
+"Brake Power"
+        BrakePower = WorkOut;
+
+"Brake Power"
+        BrakePower = (FluidPower/MechanicalEff)-PowerLoss;
+
+"Power Loss"
+        PowerLoss = BrakePower - FluidPower;
+
+end