Esempio n. 1
0
    def test_hover(self):
        # num_nodes = 40
        nstart = 0
        nend = 39
        num_nodes = nend - nstart + 1
        chord = 0.060
        theta = 0.0
        Rtip = 0.656
        Rhub = 0.19 * Rtip
        rho = 1.225
        omega = 800.0 * np.pi / 30
        Vinf = 0.0
        turbine = False
        B = 3

        r = np.linspace(Rhub + 0.01 * Rtip, Rtip - 0.01 * Rtip, 30)
        num_radial = r.shape[-1]
        r = np.tile(r, (num_nodes, 1))

        chord = np.tile(chord, (num_nodes, num_radial))
        theta = np.tile(theta, (num_nodes, num_radial))

        # Airfoil interpolator.
        af = af_from_files(["airfoils/naca0012v2.txt"])[0]

        pitch = np.linspace(1e-4, 20 * np.pi / 180, 40)[nstart:nend + 1]
        prob = om.Problem()

        comp = om.IndepVarComp()
        comp.add_output('v', val=Vinf, shape=num_nodes, units='m/s')
        comp.add_output('omega', val=np.tile(omega, num_nodes), units='rad/s')
        comp.add_output('radii',
                        val=r,
                        shape=(num_nodes, num_radial),
                        units='m')
        comp.add_output('chord',
                        val=chord,
                        shape=(num_nodes, num_radial),
                        units='m')
        comp.add_output('theta',
                        val=theta,
                        shape=(num_nodes, num_radial),
                        units='rad')
        comp.add_output('precone', val=0., shape=num_nodes, units='rad')
        comp.add_output('rho', val=rho, shape=(num_nodes, 1), units='kg/m**3')
        comp.add_output('mu', val=1.0, shape=(num_nodes, 1), units='N/m**2*s')
        comp.add_output('asound', val=1.0, shape=(num_nodes, 1), units='m/s')
        comp.add_output('hub_radius', val=Rhub, shape=num_nodes, units='m')
        comp.add_output('prop_radius', val=Rtip, shape=num_nodes, units='m')
        comp.add_output('pitch', val=pitch, shape=num_nodes, units='rad')
        prob.model.add_subsystem('ivc', comp, promotes_outputs=['*'])

        comp = SimpleInflow(num_nodes=num_nodes, num_radial=num_radial)
        prob.model.add_subsystem(
            "simple_inflow",
            comp,
            promotes_inputs=["v", "omega", "radii", "precone"],
            promotes_outputs=["Vx", "Vy"])

        comp = ccb.LocalInflowAngleComp(num_nodes=num_nodes,
                                        num_radial=num_radial,
                                        num_blades=B,
                                        airfoil_interp=af,
                                        turbine=turbine,
                                        debug_print=False)
        comp.linear_solver = om.DirectSolver(assemble_jac=True)
        prob.model.add_subsystem('ccblade',
                                 comp,
                                 promotes_inputs=[
                                     'radii', 'chord', 'theta', 'Vx', 'Vy',
                                     'rho', 'mu', 'asound', 'hub_radius',
                                     'prop_radius', 'precone', 'pitch'
                                 ],
                                 promotes_outputs=['Np', 'Tp'])

        comp = ccb.FunctionalsComp(num_nodes=num_nodes,
                                   num_radial=num_radial,
                                   num_blades=B)
        prob.model.add_subsystem(
            'ccblade_torquethrust_comp',
            comp,
            promotes_inputs=[
                'hub_radius', 'prop_radius', 'radii', 'Np', 'Tp', 'v', 'omega'
            ],
            promotes_outputs=['thrust', 'torque', 'efficiency'])

        prob.setup()
        prob.final_setup()
        prob.run_model()

        # these are not directly from the experimental data, but have been compared to the experimental data and compare favorably.
        # this is more of a regression test on the Vx=0 case
        CTcomp = np.array([
            9.452864991304056e-9, 6.569947366946672e-5, 0.00022338783939012262,
            0.0004420355541809959, 0.0007048495858030926,
            0.0010022162314665929, 0.0013268531109981317,
            0.0016736995380106938, 0.0020399354072946035,
            0.0024223576277264307, 0.0028189858460418893,
            0.0032281290309981213, 0.003649357660426685, 0.004081628946214875,
            0.004526034348853718, 0.004982651929181267, 0.0054553705714941,
            0.005942700094508395, 0.006447634897014323, 0.006963626871239654,
            0.007492654931894796, 0.00803866268066438, 0.008597914974368199,
            0.009163315934297088, 0.00973817187875574, 0.010309276997090536,
            0.010827599471613264, 0.011322361524464346, 0.01180210507896255,
            0.012276543435307877, 0.012749323136224754, 0.013223371028562213,
            0.013697833731701945, 0.01417556699620018, 0.014646124777465859,
            0.015112116772851365, 0.015576452747370885, 0.01602507607909594,
            0.016461827164870473, 0.016880126012974343
        ])
        CQcomp = np.array([
            0.000226663607327854, 0.0002270862930229147, 0.0002292742856722754,
            0.00023412703235791698, 0.00024192624628054639,
            0.0002525855612031453, 0.00026638347417704255,
            0.00028314784456601373, 0.00030299181501156373,
            0.0003259970210015136, 0.00035194661281707764,
            0.00038102864688744595, 0.0004132249034847219,
            0.00044859355432807347, 0.0004873204055790553,
            0.0005293656187218555, 0.0005753409000182888,
            0.0006250099998058788, 0.0006788861946930185,
            0.0007361096750412038, 0.0007970800153713466,
            0.0008624036743669367, 0.0009315051772818803,
            0.0010035766105979213, 0.0010791941808362153,
            0.0011566643573792704, 0.001229236439467123, 0.0013007334425769355,
            0.001372124993921022, 0.0014449961686871802, 0.0015197156782734364,
            0.0015967388663224156, 0.0016761210460920718,
            0.0017578748614666766, 0.0018409716992061841,
            0.0019248522013432586, 0.0020103360819251357, 0.002096387027559033,
            0.002182833604491109, 0.0022686470790128036
        ])
        T = prob.get_val('thrust', units='N')
        Q = prob.get_val('torque', units='N*m')
        A = np.pi * Rtip**2
        CT = T / (rho * A * (omega * Rtip)**2)
        CQ = Q / (rho * A * (omega * Rtip)**2 * Rtip)

        assert_array_almost_equal(CT, CTcomp[nstart:nend + 1], decimal=3)
        assert_array_almost_equal(CQ, CQcomp[nstart:nend + 1], decimal=3)
Esempio n. 2
0
    def test_turbine_example(self):
        # Example from the tutorial in the CCBlade documentation.

        num_nodes = 1
        turbine = True

        Rhub = np.array([1.5]).reshape((num_nodes, 1))
        Rtip = np.array([63.0]).reshape((num_nodes, 1))
        num_blades = 3
        precone = np.array([2.5 * np.pi / 180.0]).reshape((num_nodes, 1))

        r = np.array([
            2.8667, 5.6000, 8.3333, 11.7500, 15.8500, 19.9500, 24.0500,
            28.1500, 32.2500, 36.3500, 40.4500, 44.5500, 48.6500, 52.7500,
            56.1667, 58.9000, 61.6333
        ]).reshape(num_nodes, -1)
        num_radial = r.shape[-1]

        chord = np.array([
            3.542, 3.854, 4.167, 4.557, 4.652, 4.458, 4.249, 4.007, 3.748,
            3.502, 3.256, 3.010, 2.764, 2.518, 2.313, 2.086, 1.419
        ]).reshape((num_nodes, num_radial))

        theta = np.pi / 180 * np.array([
            13.308, 13.308, 13.308, 13.308, 11.480, 10.162, 9.011, 7.795,
            6.544, 5.361, 4.188, 3.125, 2.319, 1.526, 0.863, 0.370, 0.106
        ]).reshape((num_nodes, num_radial))

        rho = np.array([1.225]).reshape((num_nodes, 1))
        vhub = np.array([10.0]).reshape((num_nodes, 1))
        tsr = 7.55
        rotorR = Rtip * np.cos(precone)
        omega = vhub * tsr / rotorR

        yaw = np.array([0.0]).reshape((num_nodes, 1))
        tilt = np.array([5.0 * np.pi / 180.0]).reshape((num_nodes, 1))
        hub_height = np.array([90.0]).reshape((num_nodes, 1))
        shear_exp = np.array([0.2]).reshape((num_nodes, 1))
        azimuth = np.array([0.0]).reshape((num_nodes, 1))
        pitch = np.array([0.0]).reshape((num_nodes, 1))

        mu = np.array([1.]).reshape((num_nodes, 1))
        asound = np.array([1.]).reshape((num_nodes, 1))

        # Define airfoils. In this case we have 8 different airfoils that we
        # load into an array. These airfoils are defined in files.
        airfoil_fnames = [
            "airfoils/Cylinder1.dat", "airfoils/Cylinder2.dat",
            "airfoils/DU40_A17.dat", "airfoils/DU35_A17.dat",
            "airfoils/DU30_A17.dat", "airfoils/DU25_A17.dat",
            "airfoils/DU21_A17.dat", "airfoils/NACA64_A17.dat"
        ]
        aftypes = af_from_files(airfoil_fnames)

        # indices correspond to which airfoil is used at which station
        af_idx = [1, 1, 2, 3, 4, 4, 5, 6, 6, 7, 7, 8, 8, 8, 8, 8, 8]

        # create airfoil array, adjusting for Python's zero-based indexing.
        airfoils = [aftypes[i - 1] for i in af_idx]

        prob = om.Problem()

        comp = om.IndepVarComp()
        comp.add_output('vhub', val=vhub, units='m/s')
        comp.add_output('omega', val=omega, units='rad/s')
        comp.add_output('radii', val=r, units='m')
        comp.add_output('chord', val=chord, units='m')
        comp.add_output('theta', val=theta, units='rad')
        comp.add_output('rho', val=rho, units='kg/m**3')
        comp.add_output('mu', val=mu, units='N/m**2*s')
        comp.add_output('asound', val=asound, units='m/s')
        comp.add_output('precone', val=precone, units='rad')
        comp.add_output('yaw', val=yaw, units='rad')
        comp.add_output('tilt', val=tilt, units='rad')
        comp.add_output('hub_height', val=hub_height, units='m')
        comp.add_output('shear_exp', val=shear_exp)
        comp.add_output('azimuth', val=azimuth, units='rad')
        comp.add_output('hub_radius', val=Rhub, units='m')
        comp.add_output('prop_radius', val=Rtip, units='m')
        comp.add_output('pitch', val=pitch, units='rad')
        prob.model.add_subsystem('ivc', comp, promotes=['*'])

        comp = WindTurbineInflow(num_nodes=num_nodes, num_radial=num_radial)
        prob.model.add_subsystem('inflow', comp, promotes=['*'])

        comp = ccb.LocalInflowAngleComp(num_nodes=num_nodes,
                                        num_radial=num_radial,
                                        num_blades=num_blades,
                                        airfoil_interp=airfoils,
                                        turbine=turbine,
                                        debug_print=False)

        prob.model.add_subsystem('ccblade', comp, promotes=['*'])

        prob.setup()
        prob.final_setup()

        prob.run_model()

        expected_phi = np.array([
            1.24151, 0.984853, 0.794433, 0.474428, 0.360879, 0.306092,
            0.261674, 0.221899, 0.19487, 0.170476, 0.151866, 0.142013,
            0.129982, 0.118756, 0.108178, 0.0976137, 0.0887128
        ])
        assert_rel_error(self, expected_phi, prob['ccblade.phi'][0, :], 1e-5)
Esempio n. 3
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    def test_multiple_adv_ratios(self):
        # num_nodes = 20
        nstart = 0
        nend = 19
        num_nodes = nend - nstart + 1

        r = 0.0254 * np.array([
            0.7526, 0.7928, 0.8329, 0.8731, 0.9132, 0.9586, 1.0332, 1.1128,
            1.1925, 1.2722, 1.3519, 1.4316, 1.5114, 1.5911, 1.6708, 1.7505,
            1.8302, 1.9099, 1.9896, 2.0693, 2.1490, 2.2287, 2.3084, 2.3881,
            2.4678, 2.5475, 2.6273, 2.7070, 2.7867, 2.8661, 2.9410
        ]).reshape(1, -1)
        num_radial = r.shape[-1]
        r = np.tile(r, (num_nodes, 1))

        chord = 0.0254 * np.array([
            0.6270, 0.6255, 0.6231, 0.6199, 0.6165, 0.6125, 0.6054, 0.5973,
            0.5887, 0.5794, 0.5695, 0.5590, 0.5479, 0.5362, 0.5240, 0.5111,
            0.4977, 0.4836, 0.4689, 0.4537, 0.4379, 0.4214, 0.4044, 0.3867,
            0.3685, 0.3497, 0.3303, 0.3103, 0.2897, 0.2618, 0.1920
        ]).reshape((1, num_radial))
        chord = np.tile(chord, (num_nodes, 1))

        theta = np.pi / 180.0 * np.array([
            40.2273, 38.7657, 37.3913, 36.0981, 34.8803, 33.5899, 31.6400,
            29.7730, 28.0952, 26.5833, 25.2155, 23.9736, 22.8421, 21.8075,
            20.8586, 19.9855, 19.1800, 18.4347, 17.7434, 17.1005, 16.5013,
            15.9417, 15.4179, 14.9266, 14.4650, 14.0306, 13.6210, 13.2343,
            12.8685, 12.5233, 12.2138
        ]).reshape((1, num_radial))
        theta = np.tile(theta, (num_nodes, 1))

        rho = 1.225
        Rhub = 0.0254 * .5
        Rtip = 0.0254 * 3.0
        B = 2  # number of blades
        turbine = False

        J = np.linspace(0.1, 0.9, 20)[nstart:nend + 1]  # advance ratio
        # J = np.linspace(0.1, 0.9, 20)

        omega = 8000.0 * np.pi / 30

        n = omega / (2 * np.pi)
        D = 2 * Rtip

        Vinf = J * D * n
        dr = r[0, 1] - r[0, 0]

        # Airfoil interpolator.
        af = af_from_files(["airfoils/NACA64_A17.dat"])[0]

        prob = om.Problem()

        comp = om.IndepVarComp()
        comp.add_output('v', val=Vinf, units='m/s')
        comp.add_output('omega', val=np.tile(omega, num_nodes), units='rad/s')
        comp.add_output('radii',
                        val=r,
                        shape=(num_nodes, num_radial),
                        units='m')
        comp.add_output('dradii',
                        val=dr,
                        shape=(num_nodes, num_radial),
                        units='m')
        comp.add_output('chord',
                        val=chord,
                        shape=(num_nodes, num_radial),
                        units='m')
        comp.add_output('theta',
                        val=theta,
                        shape=(num_nodes, num_radial),
                        units='rad')
        comp.add_output('precone', val=0., shape=num_nodes, units='rad')
        comp.add_output('rho', val=rho, shape=(num_nodes, 1), units='kg/m**3')
        comp.add_output('mu', val=1.0, shape=(num_nodes, 1), units='N/m**2*s')
        comp.add_output('asound', val=1.0, shape=(num_nodes, 1), units='m/s')
        comp.add_output('hub_radius', val=Rhub, shape=num_nodes, units='m')
        comp.add_output('prop_radius', val=Rtip, shape=num_nodes, units='m')
        comp.add_output('pitch', val=0.0, shape=num_nodes, units='rad')
        prob.model.add_subsystem('ivc', comp, promotes_outputs=['*'])

        comp = SimpleInflow(num_nodes=num_nodes, num_radial=num_radial)
        prob.model.add_subsystem(
            "simple_inflow",
            comp,
            promotes_inputs=["v", "omega", "radii", "precone"],
            promotes_outputs=["Vx", "Vy"])

        comp = ccb.LocalInflowAngleComp(num_nodes=num_nodes,
                                        num_radial=num_radial,
                                        num_blades=B,
                                        airfoil_interp=af,
                                        turbine=turbine,
                                        debug_print=False)
        comp.linear_solver = om.DirectSolver(assemble_jac=True)
        prob.model.add_subsystem('ccblade',
                                 comp,
                                 promotes_inputs=[
                                     'radii', 'chord', 'theta', 'Vx', 'Vy',
                                     'rho', 'mu', 'asound', 'hub_radius',
                                     'prop_radius', 'precone', 'pitch'
                                 ],
                                 promotes_outputs=['Np', 'Tp'])

        comp = ccb.FunctionalsComp(num_nodes=num_nodes,
                                   num_radial=num_radial,
                                   num_blades=B)
        prob.model.add_subsystem(
            'ccblade_torquethrust_comp',
            comp,
            promotes_inputs=[
                'hub_radius', 'prop_radius', 'radii', 'Np', 'Tp', 'v', 'omega'
            ],
            promotes_outputs=['thrust', 'torque', 'efficiency'])

        prob.setup()
        prob.final_setup()
        prob.run_model()

        etatest = np.array([
            0.24598190455626265, 0.3349080300487075, 0.4155652767326253,
            0.48818637673414306, 0.5521115225679999, 0.6089123481436948,
            0.6595727776885079, 0.7046724703349897, 0.7441662053086512,
            0.7788447616541276, 0.8090611349633181, 0.8347808848055981,
            0.8558196582739432, 0.8715046719672315, 0.8791362131978436,
            0.8670633642311274, 0.7974063895510229, 0.2715632768892098, 0.0,
            0.0
        ])[nstart:nend + 1]

        thrust = prob.get_val('thrust', units='N')
        eff = prob.get_val('efficiency')
        assert_array_almost_equal(eff[thrust > 0.0],
                                  etatest[thrust > 0.0],
                                  decimal=2)
Esempio n. 4
0
    def test_propeller_example(self):
        # Example from the tutorial in the CCBlade documentation.

        num_nodes = 1
        turbine = False

        Rhub = np.array([0.5 * 0.0254]).reshape((1, 1))
        Rtip = np.array([3.0 * 0.0254]).reshape((1, 1))
        num_blades = 2
        precone = np.array([0.0]).reshape((1, 1))

        r = 0.0254 * np.array([
            0.7526, 0.7928, 0.8329, 0.8731, 0.9132, 0.9586, 1.0332, 1.1128,
            1.1925, 1.2722, 1.3519, 1.4316, 1.5114, 1.5911, 1.6708, 1.7505,
            1.8302, 1.9099, 1.9896, 2.0693, 2.1490, 2.2287, 2.3084, 2.3881,
            2.4678, 2.5475, 2.6273, 2.7070, 2.7867, 2.8661, 2.9410
        ]).reshape(1, -1)
        num_radial = r.shape[-1]

        chord = 0.0254 * np.array([
            0.6270, 0.6255, 0.6231, 0.6199, 0.6165, 0.6125, 0.6054, 0.5973,
            0.5887, 0.5794, 0.5695, 0.5590, 0.5479, 0.5362, 0.5240, 0.5111,
            0.4977, 0.4836, 0.4689, 0.4537, 0.4379, 0.4214, 0.4044, 0.3867,
            0.3685, 0.3497, 0.3303, 0.3103, 0.2897, 0.2618, 0.1920
        ]).reshape((1, num_radial))

        theta = np.pi / 180.0 * np.array([
            40.2273, 38.7657, 37.3913, 36.0981, 34.8803, 33.5899, 31.6400,
            29.7730, 28.0952, 26.5833, 25.2155, 23.9736, 22.8421, 21.8075,
            20.8586, 19.9855, 19.1800, 18.4347, 17.7434, 17.1005, 16.5013,
            15.9417, 15.4179, 14.9266, 14.4650, 14.0306, 13.6210, 13.2343,
            12.8685, 12.5233, 12.2138
        ]).reshape((1, num_radial))

        rho = np.array([1.225]).reshape((num_nodes, 1))
        Vinf = np.array([10.0]).reshape((num_nodes, 1))
        omega = np.array([8000.0 * (2 * np.pi / 60.0)]).reshape((num_nodes, 1))

        Vy = omega * r * np.cos(precone)
        Vx = np.tile(Vinf * np.cos(precone), (1, num_radial))
        mu = np.array([1.]).reshape((num_nodes, 1))
        asound = np.array([1.]).reshape((num_nodes, 1))
        pitch = np.array([0.0]).reshape((num_nodes, 1))

        # Airfoil interpolator.
        af = af_from_files(["airfoils/NACA64_A17.dat"])[0]

        prob = om.Problem()

        comp = ccb.LocalInflowAngleComp(num_nodes=num_nodes,
                                        num_radial=num_radial,
                                        num_blades=num_blades,
                                        airfoil_interp=af,
                                        turbine=turbine,
                                        debug_print=False)
        comp.linear_solver = om.DirectSolver(assemble_jac=True)

        prob.model.add_subsystem('ccblade', comp)

        prob.setup()
        prob.final_setup()

        prob['ccblade.phi'] = 1.
        prob['ccblade.radii'] = r
        prob['ccblade.chord'] = chord
        prob['ccblade.theta'] = theta
        prob['ccblade.Vx'] = Vx
        prob['ccblade.Vy'] = Vy
        prob['ccblade.rho'] = rho
        prob['ccblade.mu'] = mu
        prob['ccblade.asound'] = asound
        prob['ccblade.hub_radius'] = Rhub
        prob['ccblade.prop_radius'] = Rtip
        prob['ccblade.precone'] = precone
        prob['ccblade.pitch'] = pitch

        prob.run_model()

        Nptest = np.array([
            1.8660880922356378, 2.113489633244873, 2.35855792055661,
            2.60301402945597, 2.844874233881403, 3.1180230827072126,
            3.560077224628854, 4.024057801497014, 4.480574891998562,
            4.9279550384928275, 5.366395080074933, 5.79550918136406,
            6.21594163851808, 6.622960527391846, 7.017012349498324,
            7.3936834781240774, 7.751945902955048, 8.086176029603802,
            8.393537672577372, 8.67090062789216, 8.912426896510306,
            9.111379449026037, 9.264491105426602, 9.361598738055728,
            9.397710628068818, 9.360730779314666, 9.236967116872792,
            9.002418776792911, 8.617229305924996, 7.854554211296309,
            5.839491141636506
        ])
        Tptest = np.array([
            1.481919153409856, 1.5816880353415623, 1.6702432911163534,
            1.7502397903925069, 1.822089134395204, 1.8965254874252537,
            2.0022647148294554, 2.097706171361262, 2.178824887386094,
            2.2475057498944886, 2.3058616094094666, 2.355253913018444,
            2.3970643308370168, 2.4307239254050717, 2.4574034513165794,
            2.4763893383410522, 2.488405728268889, 2.492461784055084,
            2.4887264544021237, 2.4772963155708783, 2.457435891854637,
            2.4282986089025607, 2.3902927838322237, 2.3418848562229155,
            2.283388513786012, 2.2134191689454954, 2.130781255778788,
            2.0328865955896, 1.9153448642630952, 1.7308451522888118,
            1.2736544011110416
        ])
        unormtest = np.array([
            0.1138639166930624, 0.1215785884908478, 0.12836706426605704,
            0.13442694075150818, 0.13980334658952898, 0.14527249541450538,
            0.15287706861957473, 0.15952130275430465, 0.16497198426904225,
            0.16942902209255595, 0.17308482185019125, 0.17607059901193356,
            0.17850357997819633, 0.1803781237713692, 0.18177831882512596,
            0.18267665167815783, 0.18311924527883217, 0.18305367052760668,
            0.182487470134022, 0.1814205780851561, 0.17980424363698078,
            0.1775794222894007, 0.1747493664535781, 0.1712044765873724,
            0.1669243629724566, 0.16177907188793106, 0.155616714947619,
            0.14815634397029886, 0.13888287431637295, 0.12464247057085576,
            0.09292645450646951
        ])
        vnormtest = np.array([
            0.09042291182918308, 0.090986677078917, 0.09090479653774426,
            0.09038728871285233, 0.08954144817337718, 0.08836143378908702,
            0.08598138211326231, 0.08315706129440237, 0.08022297890584436,
            0.07727195122065926, 0.07437202068064472, 0.07155384528141737,
            0.06883664444997291, 0.0662014244622726, 0.06365995181515205,
            0.061184457505937574, 0.05878201223442723, 0.056423985398129595,
            0.05410845965501752, 0.05183227774671869, 0.04957767474023305,
            0.04732717658478895, 0.04508635659098153, 0.04282827989707323,
            0.04055808783300249, 0.03825394697198818, 0.0358976247398962,
            0.033456013675480394, 0.030869388594900515, 0.027466462150913407,
            0.020268236545135546
        ])

        assert_array_almost_equal(prob.get_val('ccblade.Np',
                                               units='N/m')[0, :],
                                  Nptest,
                                  decimal=2)
        assert_array_almost_equal(prob.get_val('ccblade.Tp',
                                               units='N/m')[0, :],
                                  Tptest,
                                  decimal=2)
        assert_array_almost_equal(
            (prob.get_val('ccblade.u', units='m/s') / Vinf)[0, :],
            unormtest,
            decimal=2)
        assert_array_almost_equal(
            (prob.get_val('ccblade.v', units='m/s') / Vinf)[0, :],
            vnormtest,
            decimal=2)