Merge pull request #898 from xjjiang/FLOPS_anti_icing

Flops anti-icing mass computation update

Author: Kenneth-T-Moore

aviary/subsystems/aerodynamics/gasp_based/test/test_common.py

@@ -3,6 +3,7 @@
 import numpy as np
 import openmdao.api as om
 from openmdao.utils.assert_utils import assert_check_partials, assert_near_equal
+from openmdao.utils.testing_utils import use_tempdirs
 
 from aviary.subsystems.aerodynamics.gasp_based.common import (
     AeroForces,
@@ -13,6 +14,7 @@
 from aviary.variable_info.variables import Aircraft, Dynamic
 
 
+@use_tempdirs
 class TestAeroForces(unittest.TestCase):
     def testAeroForces(self):
         nn = 3

aviary/subsystems/mass/flops_based/anti_icing.py

@@ -20,6 +20,7 @@ class AntiIcingMass(om.ExplicitComponent):
     def initialize(self):
         add_aviary_option(self, Aircraft.Engine.NUM_ENGINES)
         add_aviary_option(self, Aircraft.Propulsion.TOTAL_NUM_ENGINES)
+        add_aviary_option(self, Aircraft.Engine.REFERENCE_SLS_THRUST, units='lbf')
 
     def setup(self):
         num_engine_type = len(self.options[Aircraft.Engine.NUM_ENGINES])
@@ -29,6 +30,9 @@ def setup(self):
         add_aviary_input(self, Aircraft.Nacelle.AVG_DIAMETER, shape=num_engine_type, units='ft')
         add_aviary_input(self, Aircraft.Wing.SPAN, units='ft')
         add_aviary_input(self, Aircraft.Wing.SWEEP, units='deg')
+        add_aviary_input(
+            self, Aircraft.Engine.SCALED_SLS_THRUST, shape=num_engine_type, units='lbf'
+        )
 
         add_aviary_output(self, Aircraft.AntiIcing.MASS, units='lbm')
 
@@ -45,8 +49,13 @@ def compute(self, inputs, outputs):
         span = inputs[Aircraft.Wing.SPAN]
         sweep = inputs[Aircraft.Wing.SWEEP]
 
+        thrust = inputs[Aircraft.Engine.SCALED_SLS_THRUST]
+        ref_sls_thrust, _ = self.options[Aircraft.Engine.REFERENCE_SLS_THRUST]
+        thrust_rat = thrust / ref_sls_thrust
+        adjusted_avg_diam = avg_diam * np.sqrt(thrust_rat)
+
         count_factor = distributed_engine_count_factor(total_engines)
-        f_nacelle = distributed_nacelle_diam_factor(avg_diam, num_engines)
+        f_nacelle = distributed_nacelle_diam_factor(adjusted_avg_diam, num_engines)
 
         outputs[Aircraft.AntiIcing.MASS] = (
             (
@@ -65,11 +74,18 @@ def compute_partials(self, inputs, J):
         scaler = inputs[Aircraft.AntiIcing.MASS_SCALER]
         max_width = inputs[Aircraft.Fuselage.MAX_WIDTH]
         avg_diam = inputs[Aircraft.Nacelle.AVG_DIAMETER]
-        count_factor = distributed_engine_count_factor(total_engines)
-        f_nacelle = distributed_nacelle_diam_factor(avg_diam, num_engines)
         span = inputs[Aircraft.Wing.SPAN]
         sweep = inputs[Aircraft.Wing.SWEEP]
 
+        # scale avg_diam by thrust ratio
+        thrust = inputs[Aircraft.Engine.SCALED_SLS_THRUST]
+        ref_sls_thrust, _ = self.options[Aircraft.Engine.REFERENCE_SLS_THRUST]
+        thrust_rat = thrust / ref_sls_thrust
+        adjusted_avg_diam = avg_diam * np.sqrt(thrust_rat)
+
+        count_factor = distributed_engine_count_factor(total_engines)
+        f_nacelle = distributed_nacelle_diam_factor(adjusted_avg_diam, num_engines)
+
         diam_deriv_fact = distributed_nacelle_diam_factor_deriv(num_engines)
 
         cos_sweep = np.cos(sweep * np.pi / 180)
@@ -82,11 +98,23 @@ def compute_partials(self, inputs, J):
         J[Aircraft.AntiIcing.MASS, Aircraft.Fuselage.MAX_WIDTH] = 1.5 * scaler / GRAV_ENGLISH_LBM
 
         J[Aircraft.AntiIcing.MASS, Aircraft.Nacelle.AVG_DIAMETER] = (
-            3.8 * diam_deriv_fact * count_factor * scaler / GRAV_ENGLISH_LBM
+            3.8 * diam_deriv_fact * np.sqrt(thrust_rat) * count_factor * scaler / GRAV_ENGLISH_LBM
         )
 
         J[Aircraft.AntiIcing.MASS, Aircraft.Wing.SPAN] = 1 / cos_sweep * scaler / GRAV_ENGLISH_LBM
 
         J[Aircraft.AntiIcing.MASS, Aircraft.Wing.SWEEP] = (
             span * (np.pi / 180) * sin_sweep / (cos_sweep) ** 2 * scaler / GRAV_ENGLISH_LBM
         )
+
+        J[Aircraft.AntiIcing.MASS, Aircraft.Engine.SCALED_SLS_THRUST] = (
+            3.8
+            * diam_deriv_fact
+            * avg_diam
+            * 0.5
+            * np.sqrt(ref_sls_thrust / thrust)
+            / ref_sls_thrust
+            * count_factor
+            * scaler
+            / GRAV_ENGLISH_LBM
+        )

aviary/subsystems/mass/flops_based/test/test_anti_icing.py

@@ -44,6 +44,7 @@ def test_case(self, case_name):
                 Aircraft.Nacelle.AVG_DIAMETER,
                 Aircraft.Wing.SPAN,
                 Aircraft.Wing.SWEEP,
+                Aircraft.Engine.SCALED_SLS_THRUST,
             ],
             output_keys=Aircraft.AntiIcing.MASS,
             tol=3.0e-3,
@@ -73,6 +74,15 @@ def test_case_2(self):
         prob.set_val(Aircraft.Nacelle.AVG_DIAMETER, np.array([7.94]), 'ft')
         prob.set_val(Aircraft.Wing.SPAN, 117.83, 'ft')
         prob.set_val(Aircraft.Wing.SWEEP, 25.0, 'deg')
+        prob.set_val(
+            Aircraft.Engine.SCALED_SLS_THRUST,
+            np.array(
+                [
+                    28928.1,
+                ]
+            ),
+            'lbf',
+        )
 
         prob.run_model()
 
@@ -100,6 +110,9 @@ def test_case_3(self):
         )
 
         prob.model_options['*'] = options
+        prob.model_options[Aircraft.Engine.REFERENCE_SLS_THRUST] = np.array(
+            [28928.1, 28928.1, 28928.1]
+        )
 
         prob.setup(check=False, force_alloc_complex=True)
 
@@ -108,6 +121,9 @@ def test_case_3(self):
         prob.set_val(Aircraft.Nacelle.AVG_DIAMETER, np.array([7.94, 8, 5]), 'ft')
         prob.set_val(Aircraft.Wing.SPAN, 117.83, 'ft')
         prob.set_val(Aircraft.Wing.SWEEP, 25.0, 'deg')
+        prob.set_val(
+            Aircraft.Engine.SCALED_SLS_THRUST, np.array([28928.1, 28928.1, 28928.1]), 'lbf'
+        )
 
         prob.run_model()
 
@@ -158,6 +174,15 @@ def test_case_2(self):
         prob.set_val(Aircraft.Nacelle.AVG_DIAMETER, np.array([7.94]), 'ft')
         prob.set_val(Aircraft.Wing.SPAN, 117.83, 'ft')
         prob.set_val(Aircraft.Wing.SWEEP, 25.0, 'deg')
+        prob.set_val(
+            Aircraft.Engine.SCALED_SLS_THRUST,
+            np.array(
+                [
+                    28928.1,
+                ]
+            ),
+            'lbf',
+        )
 
         partial_data = prob.check_partials(out_stream=None, method='cs')
         assert_check_partials(partial_data, atol=1e-12, rtol=1e-12)