update valve calc (#1210)

Author: EvenSol

src/main/java/neqsim/process/equipment/valve/ThrottlingValve.java

@@ -45,6 +45,7 @@ public class ThrottlingValve extends TwoPortEquipment implements ValveInterface
   boolean isCalcPressure = false;
   private boolean gasValve = true;
   private double Fp = 1.0;
+  private double deltaPressure = 0.0;
 
   /**
    * * Constructor for ThrottlingValve.
@@ -415,12 +416,20 @@ public double calcPercentValveOpening(double Pus, double Pds, double rhous, doub
   public void run(UUID id) {
     // System.out.println("valve running..");
     // outStream.setSpecification(inletStream.getSpecification());
-    thermoSystem = getInletStream().getThermoSystem().clone();
+    if (getInletStream().getThermoSystem() != null) {
+      thermoSystem = getInletStream().getThermoSystem().clone();
+    } else {
+      logger.error("Inlet stream thermo system is null");
+      return;
+    }
     ThermodynamicOperations thermoOps = new ThermodynamicOperations(thermoSystem);
     thermoSystem.init(3);
     double enthalpy = thermoSystem.getEnthalpy();
     inStream.getThermoSystem().initPhysicalProperties(PhysicalPropertyType.MASS_DENSITY);
     double outp = 0.0;
+    if (pressure == 0) {
+      pressure = inStream.getThermoSystem().getPressure();
+    }
 
     if (inStream.getThermoSystem().hasPhaseType(PhaseType.GAS)
         && inStream.getThermoSystem().getVolumeFraction(0) > 0.9) {
@@ -441,6 +450,12 @@ public void run(UUID id) {
       }
       setOutletPressure(outp);
     }
+    if (deltaPressure != 0) {
+      thermoSystem.setPressure(thermoSystem.getPressure(pressureUnit) - deltaPressure,
+          pressureUnit);
+      setOutletPressure(thermoSystem.getPressure());
+
+    }
 
     if ((thermoSystem.getPressure(pressureUnit) - pressure) < 0) {
       if (isAcceptNegativeDP()) {
@@ -456,14 +471,15 @@ public void run(UUID id) {
     // System.out.println("enthalpy inn.." + enthalpy);
     // thermoOps.PHflash(enthalpy, 0);
     if (isIsoThermal() || Math.abs(pressure - inStream.getThermoSystem().getPressure()) < 1e-6
-        || thermoSystem.getNumberOfMoles() < 1e-12) {
+        || thermoSystem.getNumberOfMoles() < 1e-12 || pressure == 0) {
       thermoOps.TPflash();
     } else {
       thermoOps.PHflash(enthalpy, 0);
     }
     outStream.setThermoSystem(thermoSystem);
     // System.out.println("Total volume flow " +
-    // outStream.getThermoSystem().getVolume());
+    // Uncomment the line below to get the volume of the outlet stream's thermodynamic system
+    // System.out.println("Total volume flow " + outStream.getThermoSystem().getVolume());
     // System.out.println("density valve " +
     // inletStream.getThermoSystem().getDensity());
 
@@ -522,7 +538,9 @@ public void run(UUID id) {
   }
 
   /** {@inheritDoc} */
-  @Override
+  /**
+   * This annotation is used to exclude the method from Jacoco code coverage reports.
+   */
   @ExcludeFromJacocoGeneratedReport
   public void displayResult() {
     thermoSystem.display(getName());
@@ -813,4 +831,13 @@ public double getFp() {
   public void setFp(double fp) {
     Fp = fp;
   }
+
+  public double getDeltaPressure() {
+    return deltaPressure;
+  }
+
+  public void setDeltaPressure(double deltaPressure, String unit) {
+    this.deltaPressure = deltaPressure;
+    this.pressureUnit = unit;
+  }
 }

src/test/java/neqsim/process/equipment/valve/ThrottlingValveTest.java

@@ -52,4 +52,57 @@ void testCalcCvLiquid() {
     assertEquals(100, stream1.getFlowRate("kg/hr"), 1e-2);
     assertEquals(3.015805897362369E-4, valve1.getCv("US"), 1e-2);
   }
+
+  @Test
+  void testSetDeltaPressure() {
+    neqsim.thermo.system.SystemInterface testSystem2 =
+        new neqsim.thermo.system.SystemSrkEos((273.15 + 25.0), 10.00);
+    testSystem2.addComponent("methane", 1.0);
+    testSystem2.setMixingRule(2);
+
+    Stream stream1 = new Stream("Stream1", testSystem2);
+    stream1.setFlowRate(100.0, "kg/hr");
+    stream1.setPressure(100.0, "bara");
+    stream1.setTemperature(55.0, "C");
+    stream1.run();
+
+    double deltaPressure = 10.0;
+    ThrottlingValve valve1 = new ThrottlingValve("valve_1", stream1);
+    valve1.setDeltaPressure(deltaPressure, "bara");
+    valve1.run();
+
+    Stream stream2 = new Stream("Stream1", valve1.getOutletStream());
+    stream2.getPressure("bara");
+    stream2.run();
+
+    assertEquals(deltaPressure, valve1.getDeltaPressure(), 1e-2);
+    assertEquals(deltaPressure, stream1.getPressure("bara") - stream2.getPressure("bara"), 1e-4);
+    assertEquals(52.269428855, stream2.getTemperature("C"), 1e-2);
+  }
+
+  @Test
+  void testSetDeltaPressure2() {
+    neqsim.thermo.system.SystemInterface testSystem2 =
+        new neqsim.thermo.system.SystemSrkEos((273.15 + 25.0), 10.00);
+    testSystem2.addComponent("methane", 1.0);
+    testSystem2.setMixingRule(2);
+
+    Stream stream1 = new Stream("Stream1", testSystem2);
+    stream1.setFlowRate(100.0, "kg/hr");
+    stream1.setPressure(100.0, "bara");
+    stream1.setTemperature(55.0, "C");
+    stream1.run();
+
+    double deltaPressure = 0.0;
+    ThrottlingValve valve1 = new ThrottlingValve("valve_1", stream1);
+    valve1.run();
+
+    Stream stream2 = new Stream("Stream1", valve1.getOutletStream());
+    stream2.getPressure("bara");
+    stream2.run();
+
+    assertEquals(deltaPressure, valve1.getDeltaPressure(), 1e-2);
+    assertEquals(deltaPressure, stream1.getPressure("bara") - stream2.getPressure("bara"), 1e-4);
+    assertEquals(55.0, stream2.getTemperature("C"), 1e-2);
+  }
 }