Cv method valves

src/main/java/neqsim/processSimulation/processEquipment/valve/ValveInterface.java

@@ -64,6 +64,16 @@ public interface ValveInterface extends ProcessEquipmentInterface, TwoPortInterf
    */
   public double getCv();
 
+  /**
+   * <p>
+   * getCv.
+   * </p>
+   * 
+   * @param unit can be SI or US SI is unit litre/minute US is gallons per minute
+   * @return a double
+   */
+  public double getCv(String unit);
+
   /**
    * <p>
    * setCv.
@@ -73,6 +83,16 @@ public interface ValveInterface extends ProcessEquipmentInterface, TwoPortInterf
    */
   public void setCv(double Cv);
 
+  /**
+   * <p>
+   * setCv.
+   * </p>
+   *
+   * @param Cv a double
+   * @param unit can be SI or US SI is unit litre/minute US is gallons per minute
+   */
+  public void setCv(double Cv, String unit);
+
   /** {@inheritDoc} */
   @Override
   public SystemInterface getThermoSystem();

src/main/java/neqsim/standards/oilQuality/Standard_ASTM_D6377.java

@@ -51,7 +51,7 @@ public void calculate() {
     TVP = this.thermoSystem.getPressure();
     double liquidVolume = thermoSystem.getVolume();
 
-    this.thermoSystem.setPressure(0.9);
+    this.thermoSystem.setPressure(TVP * 0.9);
     try {
       this.thermoOps.TVflash(liquidVolume * 4.0);
     } catch (Exception ex) {

src/main/java/neqsim/thermo/system/SystemThermo.java

@@ -2105,6 +2105,9 @@ public double getFlowRate(String flowunit) {
       return totalNumberOfMoles * getMolarMass() * 3600.0 / getDensity("kg/m3");
     } else if (flowunit.equals("idSm3/hr")) {
       return totalNumberOfMoles * getMolarMass() * 3600.0 / getIdealLiquidDensity("kg/m3");
+    } else if (flowunit.equals("gallons/min")) {
+      initPhysicalProperties("density");
+      return totalNumberOfMoles * getMolarMass() * 60.0 / getDensity("kg/m3") * 1000 / 3.78541178;
     } else if (flowunit.equals("Sm3/sec")) {
       return totalNumberOfMoles * ThermodynamicConstantsInterface.R
           * ThermodynamicConstantsInterface.standardStateTemperature
@@ -4914,7 +4917,8 @@ public void setTotalFlowRate(double flowRate, String flowunit) {
       logger.error(e.getMessage());
     }
     double density = 0.0;
-    if (flowunit.equals("Am3/hr") || flowunit.equals("Am3/min") || flowunit.equals("Am3/sec")) {
+    if (flowunit.equals("Am3/hr") || flowunit.equals("Am3/min") || flowunit.equals("gallons/min")
+        || flowunit.equals("Am3/sec")) {
       initPhysicalProperties("density");
     }
 

src/main/java/neqsim/thermodynamicOperations/flashOps/TVflash.java

@@ -75,8 +75,10 @@ public double solveQ() {
     double oldPres = system.getPressure();
     double nyPres = system.getPressure();
     double iterations = 1;
+    double error = 100.0, errorOld = 1000.0;
     do {
       iterations++;
+      errorOld = error;
       oldPres = nyPres;
       system.init(3);
       nyPres = oldPres - (iterations) / (iterations + 10.0) * calcdQdV() / calcdQdVV();
@@ -88,9 +90,11 @@ public double solveQ() {
       }
       system.setPressure(nyPres);
       tpFlash.run();
-      // System.out.println(" dQdv " + calcdQdV() + " new pressure " + nyPres + " error " +
-      // Math.abs((nyPres-oldPres)/(nyPres)) + " numberofphases "+system.getNumberOfPhases());
-    } while (Math.abs((nyPres - oldPres) / (nyPres)) > 1e-9 && iterations < 1000 || iterations < 3);
+      // System.out.println(" dQdv " + calcdQdV() + " new pressure " + nyPres + " error "
+      // + Math.abs((nyPres - oldPres) / (nyPres)) + " numberofphases "
+      // + system.getNumberOfPhases());
+      error = Math.abs(calcdQdV());
+    } while (Math.abs(error) > 1e-9 && iterations < 200 && error < errorOld || iterations < 3);
     return nyPres;
   }
 

src/main/java/neqsim/util/unit/RateUnit.java

@@ -103,6 +103,8 @@ public double getConversionFactor(String name) {
       factor = 1.0 / molarmass / 3600.0 * stddens;
     } else if (name.equals("idSm3/day")) {
       factor = 1.0 / molarmass / (3600.0 * 24.0) * stddens;
+    } else if (name.equals("gallons/min")) {
+      factor = 1.0 / molarmass / 60.0 * stddens / 10.0 * 3.78541178;
     } else {
       throw new RuntimeException(
           new InvalidInputException(this, "getConversionFactor", "unit", "not supported"));

src/test/java/neqsim/processSimulation/processEquipment/valve/ThrottlingValveTest.java

@@ -0,0 +1,56 @@
+package neqsim.processSimulation.processEquipment.valve;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import org.junit.jupiter.api.Test;
+import neqsim.processSimulation.processEquipment.stream.Stream;
+
+public class ThrottlingValveTest {
+  @Test
+  void testCalcCvGas() {
+    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(7000, "Sm3/hr");
+    stream1.setPressure(10.0, "bara");
+    stream1.setTemperature(55.0, "C");
+    stream1.run();
+
+    ThrottlingValve valve1 = new ThrottlingValve("valve_1", stream1);
+    valve1.setOutletPressure(5.0);
+    valve1.setPercentValveOpening(100);
+    valve1.run();
+
+    assertEquals(48.2652, valve1.getCv("US"), 1e-2);
+    assertEquals(2649.7612, valve1.getCv("SI"), 1e-2);
+
+  }
+
+  @Test
+  void testCalcCvLiquid() {
+    neqsim.thermo.system.SystemInterface testSystem2 =
+        new neqsim.thermo.system.SystemSrkEos((273.15 + 25.0), 10.00);
+    testSystem2.addComponent("water", 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();
+
+    ThrottlingValve valve1 = new ThrottlingValve("valve_1", stream1);
+    valve1.setOutletPressure(50.0);
+    valve1.setPercentValveOpening(100);
+    valve1.run();
+
+    assertEquals(0.4515327970, stream1.getFlowRate("gallons/min"), 1e-2);
+    assertEquals(0.0165567743765, valve1.getCv("SI"), 1e-2);
+    assertEquals(100.0, valve1.getPercentValveOpening(), 1e-2);
+    assertEquals(100, stream1.getFlowRate("kg/hr"), 1e-2);
+    assertEquals(3.015805897362369E-4, valve1.getCv("US"), 1e-2);
+
+  }
+}

src/test/java/neqsim/standards/oilQuality/Standard_ASTM_D6377Test.java

@@ -11,14 +11,34 @@ void testCalculate() {
     SystemInterface testSystem = new SystemSrkEos(273.15 + 2.0, 1.0);
     testSystem.addComponent("methane", 0.0006538);
     testSystem.addComponent("ethane", 0.006538);
-    testSystem.addComponent("propane", 0.006538);
+    testSystem.addComponent("propane", 0.06538);
+    testSystem.addComponent("n-pentane", 0.1545);
+    testSystem.addComponent("nC10", 0.545);
+    testSystem.setMixingRule(2);
+    testSystem.init(0);
+    Standard_ASTM_D6377 standard = new Standard_ASTM_D6377(testSystem);
+    standard.setReferenceTemperature(37.8, "C");
+    standard.calculate();
+    Assertions.assertEquals(0.94552559993, standard.getValue("RVP", "bara"), 1e-3);
+    Assertions.assertEquals(1.666298367, standard.getValue("TVP", "bara"), 1e-3);
+  }
+
+  @Test
+  void testCalculate2() {
+    SystemInterface testSystem = new SystemSrkEos(273.15 + 2.0, 1.0);
+    testSystem.addComponent("methane", 0.026538);
+    testSystem.addComponent("ethane", 0.16538);
+    testSystem.addComponent("propane", 0.26538);
     testSystem.addComponent("n-pentane", 0.545);
+    testSystem.addComponent("nC10", 0.545);
+    testSystem.addTBPfraction("C11", 0.545, 145.0 / 1000.0, 0.82);
     testSystem.setMixingRule(2);
     testSystem.init(0);
+    testSystem.setPressure(100.0);
     Standard_ASTM_D6377 standard = new Standard_ASTM_D6377(testSystem);
     standard.setReferenceTemperature(37.8, "C");
     standard.calculate();
-    //Assertions.assertEquals(0.7298246193, standard.getValue("RVP", "bara"), 1e-3);
-    Assertions.assertEquals(1.8710732396722, standard.getValue("TVP", "bara"), 1e-3);
+    Assertions.assertEquals(3.017010, standard.getValue("RVP", "bara"), 1e-3);
+    Assertions.assertEquals(7.8448385024, standard.getValue("TVP", "bara"), 1e-3);
   }
 }