Making pipe and cable substance-agnostic

CHANGELOG.md

@@ -47,6 +47,7 @@
 - Updated option to pass variables in technology interconnections to allow for different variable names from source to destination in the format `[source_tech, dest_tech, (source_tech_variable, dest_tech_variable)]`
 - Added `simulation` section under `plant_config['plant']` that has information such as number of timesteps in the simulation, time step interval in seconds, simulation start time, and time zone.
 - Added `"custom_electrolyzer_cost"` model, an electrolyzer cost model that allows for user-defined capex and opex values
+- Made `pipe` and `cable` substance-agnostic rather than hard-coded for `hydrogen` and `electricity`
 
 ## 0.3.0 [May 2 2025]
 

examples/05_wind_h2_opt/driver_config.yaml

@@ -7,11 +7,11 @@ general:
 driver:
   optimization:
     flag: True
+    solver: COBYLA
     tol: 0.1
     catol: 10000
     max_iter: 100
-    solver: COBYLA
-    rhobeg: 30
+    rhobeg: 10
     debug_print: True
 
 design_variables:
@@ -35,4 +35,4 @@ objective:
 recorder:
   flag: True
   file: "wind_h2_opt.sql"
-  includes: ["LCOH"]
+  includes: ["*"]

h2integrate/core/h2integrate_model.py

@@ -463,7 +463,9 @@ def connect_technologies(self):
                 connection_name = f"{source_tech}_to_{dest_tech}_{transport_type}"
 
                 # Create the transport object
-                connection_component = self.supported_models[transport_type]()
+                connection_component = self.supported_models[transport_type](
+                    transport_item=transport_item
+                )
 
                 # Add the connection component to the model
                 self.plant.add_subsystem(connection_name, connection_component)

h2integrate/transporters/cable.py

@@ -6,21 +6,26 @@ class CablePerformanceModel(om.ExplicitComponent):
     Pass-through cable with no losses.
     """
 
+    def initialize(self):
+        self.options.declare("transport_item", values=["electricity"])
+
     def setup(self):
+        self.input_name = self.options["transport_item"] + "_in"
+        self.output_name = self.options["transport_item"] + "_out"
         self.add_input(
-            "electricity_in",
+            self.input_name,
             val=0.0,
             shape_by_conn=True,
-            copy_shape="electricity_out",
+            copy_shape=self.output_name,
             units="kW",
         )
         self.add_output(
-            "electricity_out",
+            self.output_name,
             val=0.0,
             shape_by_conn=True,
-            copy_shape="electricity_in",
+            copy_shape=self.input_name,
             units="kW",
         )
 
     def compute(self, inputs, outputs):
-        outputs["electricity_out"] = inputs["electricity_in"]
+        outputs[self.output_name] = inputs[self.input_name]

h2integrate/transporters/pipe.py

@@ -6,21 +6,28 @@ class PipePerformanceModel(om.ExplicitComponent):
     Pass-through pipe with no losses.
     """
 
+    def initialize(self):
+        self.options.declare(
+            "transport_item", values=["hydrogen", "co2", "methanol", "ammonia", "nitrogen"]
+        )
+
     def setup(self):
+        self.input_name = self.options["transport_item"] + "_in"
+        self.output_name = self.options["transport_item"] + "_out"
         self.add_input(
-            "hydrogen_in",
+            self.input_name,
             val=0.0,
             shape_by_conn=True,
-            copy_shape="hydrogen_out",
+            copy_shape=self.output_name,
             units="kg/s",
         )
         self.add_output(
-            "hydrogen_out",
+            self.output_name,
             val=0.0,
             shape_by_conn=True,
-            copy_shape="hydrogen_in",
+            copy_shape=self.input_name,
             units="kg/s",
         )
 
     def compute(self, inputs, outputs):
-        outputs["hydrogen_out"] = inputs["hydrogen_in"]
+        outputs[self.output_name] = inputs[self.input_name]

h2integrate/transporters/test/test_pipe.py

@@ -0,0 +1,40 @@
+import pytest
+import openmdao.api as om
+from pytest import approx
+
+from h2integrate.transporters.pipe import PipePerformanceModel
+
+
+def test_pipe_with_hydrogen():
+    """Test the pipe transport with hydrogen as transport_item."""
+
+    # Create the pipe component with hydrogen as transport item
+    pipe = PipePerformanceModel(transport_item="hydrogen")
+
+    # Create OpenMDAO problem and add the component
+    prob = om.Problem()
+    prob.model.add_subsystem("pipe", pipe, promotes=["*"])
+
+    # Add independent variable component for input
+    ivc = om.IndepVarComp()
+    ivc.add_output("hydrogen_in", val=10.0, units="kg/s")
+    prob.model.add_subsystem("ivc", ivc, promotes=["*"])
+
+    # Setup and run the model
+    prob.setup()
+    prob.set_val("hydrogen_in", 10.0, units="kg/s")
+    prob.run_model()
+
+    # Check that output equals input (pass-through pipe with no losses)
+    hydrogen_in = prob.get_val("hydrogen_in", units="kg/s")
+    hydrogen_out = prob.get_val("hydrogen_out", units="kg/s")
+
+    assert hydrogen_out == approx(hydrogen_in, rel=1e-10)
+    assert hydrogen_out == approx(10.0, rel=1e-10)
+
+
+def test_pipe_with_invalid_transport_item():
+    """Test that pipe raises an error with invalid transport_item."""
+    with pytest.raises(ValueError) as excinfo:
+        PipePerformanceModel(transport_item="invalid_item")
+    assert "Value ('invalid_item')" in str(excinfo.value)