added option to add energy stream (#1202)

src/main/java/neqsim/process/equipment/compressor/Compressor.java

@@ -296,6 +296,10 @@ public void run(UUID id) {
       return;
     }
 
+    if (isSetEnergyStream()) {
+      setPower(energyStream.getDuty());
+    }
+
     ThermodynamicOperations thermoOps = new ThermodynamicOperations(getThermoSystem());
     thermoOps = new ThermodynamicOperations(getThermoSystem());
     getThermoSystem().init(3);

src/main/java/neqsim/process/equipment/expander/Expander.java

@@ -31,8 +31,7 @@ public Expander(String name) {
    * </p>
    *
    * @param name a {@link java.lang.String} object
-   * @param inletStream a {@link neqsim.process.equipment.stream.StreamInterface}
-   *        object
+   * @param inletStream a {@link neqsim.process.equipment.stream.StreamInterface} object
    */
   public Expander(String name, StreamInterface inletStream) {
     super(name, inletStream);
@@ -51,18 +50,21 @@ public void run(UUID id) {
     // double densInn = getThermoSystem().getDensity();
     double entropy = getThermoSystem().getEntropy();
     inletEnthalpy = hinn;
-
+    double hout = hinn;
     if (usePolytropicCalc) {
       int numbersteps = 40;
       double dp = (pressure - getThermoSystem().getPressure()) / (1.0 * numbersteps);
+
       for (int i = 0; i < numbersteps; i++) {
         entropy = getThermoSystem().getEntropy();
-        hinn = getThermoSystem().getEnthalpy();
+        double hinn_loc = getThermoSystem().getEnthalpy();
         getThermoSystem().setPressure(getThermoSystem().getPressure() + dp);
         thermoOps.PSflash(entropy);
-        double hout = hinn + (getThermoSystem().getEnthalpy() - hinn) * polytropicEfficiency;
+        hout = hinn_loc + (getThermoSystem().getEnthalpy() - hinn_loc) * polytropicEfficiency;
         thermoOps.PHflash(hout, 0);
       }
+
+      dH = hout - hinn;
       /*
        * HYSYS method double oldPolyt = 10.5; int iter = 0; do {
        *
@@ -87,12 +89,15 @@ public void run(UUID id) {
       if (!powerSet) {
         dH = (getThermoSystem().getEnthalpy() - hinn) * isentropicEfficiency;
       }
-      double hout = hinn + dH;
+      hout = hinn + dH;
       isentropicEfficiency = dH / (getThermoSystem().getEnthalpy() - hinn);
       // System.out.println("isentropicEfficiency.. " + isentropicEfficiency);
       dH = hout - hinn;
       thermoOps.PHflash(hout, 0);
     }
+    if (isSetEnergyStream()) {
+      energyStream.setDuty(-dH);
+    }
     // thermoSystem.display();
     outStream.setThermoSystem(getThermoSystem());
     setCalculationIdentifier(id);

src/main/java/neqsim/process/equipment/stream/EnergyStream.java

@@ -15,9 +15,16 @@
 public class EnergyStream implements java.io.Serializable, Cloneable {
   private static final long serialVersionUID = 1000;
   static Logger logger = LogManager.getLogger(EnergyStream.class);
+  private String name = "";
 
   private double duty = 0.0;
 
+  public EnergyStream() {}
+
+  public EnergyStream(String name) {
+    this.name = name;
+  }
+
   /** {@inheritDoc} */
   @Override
   public EnergyStream clone() {
@@ -73,4 +80,12 @@ public boolean equals(Object obj) {
     EnergyStream other = (EnergyStream) obj;
     return Double.doubleToLongBits(duty) == Double.doubleToLongBits(other.duty);
   }
+
+  public String getName() {
+    return name;
+  }
+
+  public void setName(String name) {
+    this.name = name;
+  }
 }

src/test/java/neqsim/process/equipment/compressor/CompressorTest.java

@@ -12,6 +12,8 @@
 import org.junit.jupiter.api.Assertions;
 import org.junit.jupiter.api.BeforeEach;
 import org.junit.jupiter.api.Test;
+import neqsim.process.equipment.expander.Expander;
+import neqsim.process.equipment.stream.EnergyStream;
 import neqsim.process.equipment.stream.Stream;
 import neqsim.process.processmodel.ProcessSystem;
 import neqsim.thermo.system.SystemSrkEos;
@@ -292,4 +294,54 @@ public void testPowerEffSpec() {
     assertEquals(139.7216108, compressor1.getOutletStream().getTemperature("C"), 0.01);
     // compressor1.getOutletStream().getFluid().prettyPrint();
   }
+
+
+  /**
+   * <p>
+   * test run with energy stream input.
+   * </p>
+   */
+  @Test
+  public void testRunWithEnergyStreamInput() {
+    SystemSrkEos testSystem = new SystemSrkEos(315.0, 10.0);
+    testSystem.addComponent("nitrogen", 2.0);
+    testSystem.addComponent("methane", 50.0);
+    testSystem.setMixingRule(2);
+
+    Stream inletStream = new Stream("feed stream", testSystem);
+    inletStream.setPressure(100, "bara");
+    inletStream.setTemperature(30, "C");
+    inletStream.setFlowRate(1, "MSm3/day");
+    inletStream.run();
+
+    EnergyStream estream1 = new EnergyStream("e_stream");
+
+    Expander expander1 = new Expander("expander 1", inletStream);
+    expander1.setPolytropicEfficiency(0.8);
+    expander1.setUsePolytropicCalc(true);
+    // expander1.setIsentropicEfficiency(1.0);
+    expander1.setOutletPressure(55.0, "bara");
+    expander1.setEnergyStream(estream1);
+    expander1.run();
+
+    assertEquals(481376.2230301, estream1.getDuty(), 0.01);
+
+    compressor1 = new Compressor("compressor 1", expander1.getOutletStream());
+    compressor1.setUsePolytropicCalc(true);
+    compressor1.setPolytropicEfficiency(0.8);
+    // compressor1.setIsentropicEfficiency(1.0);
+    compressor1.setEnergyStream(estream1);
+    compressor1.setCalcPressureOut(true);
+    compressor1.run();
+
+    assertEquals(481376.2230301, compressor1.getPower(), 0.01);
+
+    processOps = new ProcessSystem();
+    processOps.add(inletStream);
+    processOps.add(expander1);
+    processOps.add(compressor1);
+    processOps.run();
+
+    assertEquals(81.61462472, compressor1.getOutletPressure(), 0.01);
+  }
 }