Option to specify position of the RNA + slight change in test_rotor

- Besides the already available option of specifying the hub height (using input key `hHub`), now the user can also specify the coordinates of the RNA reference position (with respect to the FOWT reference frame) via the input key `rRNA`. For multirotor designs, the user needs to provide `rRNA` for each RNA/rotor

- moved the flagSaveValues to be an input of test_calcAero

examples/VolturnUS-S_example.yaml

@@ -31,7 +31,8 @@ turbine:
     IxRNA         :          0        #  [kg-m2]    RNA moment of inertia about local x axis (assumed to be identical to rotor axis for now, as approx) [kg-m^2]
     IrRNA         :          0        #  [kg-m2]    RNA moment of inertia about local y or z axes [kg-m^2]
     xCG_RNA       :          0        #  [m]        x location of RNA center of mass [m] (Actual is ~= -0.27 m)
-    hHub          :        150.0      #  [m]        hub height above water line [m]
+    hHub          :     150.0       #  [m]        hub height above water line [m]
+    #rRNA          :  [0,0, 148.742] #  [m] Can use the position of the RNA reference point (which the RNA yaws about) with respect to the FOWT reference point. If also providing hHub, the z coord be overwritten.
     Fthrust       :       1500.0E3    #  [N]        temporary thrust force to use
 
     I_drivetrain: 318628138.0   # full rotor + drivetrain inertia as felt on the high-speed shaft

raft/raft_rotor.py

@@ -46,12 +46,13 @@ def __init__(self, turbine, w, ir):
         self.turbine = turbine      # store dictionary for later use
 
         # self.r_rel is the position of the RNA reference point (which the RNA yaws about) on the FOWT
-        if 'rotorCoords' in turbine:
-            print("WARNING: turbine rotorCoords input is deprecated - use position.")
-            self.r_rel = getFromDict(turbine, 'rotorCoords', dtype=list, shape=turbine['nrotors'], default=[[0,0,100.]])[ir]
-
-        self.r_rel = getFromDict(turbine, 'position', dtype=list, shape=turbine['nrotors'], default=[[0,0,100.]])[ir]
-
+        if 'rRNA' in turbine: # Temporary if statement. Need to fix getFromDict to handle this
+            self.r_rel = getFromDict(turbine, 'rRNA', shape=[turbine['nrotors'], 3])[ir]
+        else:
+            if turbine['nrotors'] > 1:
+                raise Exception("For designs with more than one rotor, the RNA reference point must be specified for each of them.")
+            self.r_rel = [0, 0, 100.]
+
         self.overhang   = getFromDict(turbine, 'overhang', shape=turbine['nrotors'])[ir]  # rotor offset in +x before yaw [m]
         if self.overhang > 0:
             print("WARNING: The turbine overhang input was positive for upwind turbines.")
@@ -105,12 +106,12 @@ def __init__(self, turbine, w, ir):
 
         self.R_ptfm  = np.ones(3)  # rotation matrix for platform orientation 
 
+        # If `hHub` is specified, we overwrite the z-coordinate of the RNA reference point
         if 'hHub' in turbine:
-            print("WARNING: turbine hHub input is deprecated - use position [x y z].")     
             hHub    = getFromDict(turbine, 'hHub'   , shape=turbine['nrotors'])[ir]  # overwrites r_rel[2] [m]
             self.r_rel[2] = hHub - self.q[2]*self.overhang
-        self.hHub = hHub  # we may not need this anymore
-        self.Zhub = self.hHub         
+        self.hHub = self.r_rel[2] + self.q[2]*self.overhang  # we may not need this anymore
+        self.Zhub = self.hHub
 
         # below is initialization, needs to be updated by setPosition...
         self.r_RRP = np.array(self.r_rel)  # RNA reference point

tests/test_rotor.py

@@ -80,18 +80,16 @@ def index_and_rotor(request):
 '''
  Test functions
 '''
-def test_calcAero(index_and_rotor):    
+def test_calcAero(index_and_rotor, flagSaveValues=False):    
     '''
     Verify rotor.calcAero for many combinations of wind speed, heading, TI, and yaw mode.
     Some combinations seem to be outside the validity of CCBlade (e.g., yaw_mode=1, wind direction=90, and turbine_heading=0),
     but they are tested nonetheless.
+    Set flagSaveValues to true to replace the true values file with the values calculated below
     '''
     index, rotor = index_and_rotor
     rotor.setPosition()
 
-    # Set this flag to true to replace the true values file
-    flagSaveValues = False
-
     if 'IEA15MW' in list_files[index]:
         U_rated = 10.59
     elif 'NREL5MW' in list_files[index]:
@@ -160,5 +158,5 @@ def test_calcAero(index_and_rotor):
     index = 0
 
     rotor = create_rotor(list_files[index])
-    test_calcAero((index, rotor))
+    test_calcAero((index, rotor), flagSaveValues=False)