def compute_noise(config, analyses, noise_segment):
turbofan = config.propulsors[0]
outputfile = config.output_file
outputfile_engine = config.output_file_engine
print_output = config.print_output
engine_flag = config.engine_flag # remove engine noise component from the approach segment
airframe_noise = noise_airframe_Fink(config, analyses, noise_segment, print_output, outputfile)
engine_noise = noise_SAE(turbofan, noise_segment, config, analyses, print_output, outputfile_engine)
noise_sum = 10. * np.log10(10 ** (airframe_noise[0] / 10) + engine_flag * 10 ** (engine_noise[0] / 10))
return noise_sum
def compute_noise(config, analyses, noise_segment, noise_settings):
"""This method computes the noise of a turbofan aircraft
Assumptions:
N/A
Source:
N/A
Inputs:
config.
networks.turbofan - SUAVE turbofan data structure [None]
output_file - flag to write noise outout to file [Boolean]
output_file_engine - flag to write engine outout to file [Boolean]
print_output - flag to print outout to file [Boolean]
engine_flag - flag to include engine in noise calculation [Boolean]
Outputs:
noise_sum [dB]
Properties Used:
N/A
"""
turbofan = config.networks['turbofan']
outputfile = config.output_file
outputfile_engine = config.output_file_engine
print_output = config.print_output
engine_flag = config.engine_flag
geometric = noise_geometric(noise_segment, analyses, config)
airframe_noise = noise_airframe_Fink(noise_segment, analyses, config,
noise_settings, print_output,
outputfile)
engine_noise = noise_SAE(turbofan, noise_segment, analyses, config,
noise_settings, print_output, outputfile_engine)
noise_sum = 10. * np.log10(10**(airframe_noise.EPNL_total / 10) +
(engine_flag) * 10**
(engine_noise.EPNL_total / 10))
return noise_sum
def evaluate_noise(self, segment):
""" Process vehicle to setup geometry, condititon and configuration
Assumptions:
None
Source:
N/4
Inputs:
self.settings.
ground_microphone_phi_angles - azimuth measured from observer to aircraft body frame [radians]
ground_microphone_theta_angles - axial angle measured from observer to aircraft body frame [radians]
center_frequencies - 1/3 octave band frequencies [unitless]
Outputs:
None
Properties Used:
self.geometry
"""
# unpack
config = segment.analyses.noise.geometry
analyses = segment.analyses
settings = self.settings
conditions = segment.state.conditions
print_flag = settings.print_noise_output
# unpack
alt = -conditions.frames.inertial.position_vector[:, 2]
gm_phi = settings.ground_microphone_phi_angles
gm_theta = settings.ground_microphone_theta_angles
cf = settings.center_frequencies
dim_alt = len(alt)
dim_phi = len(gm_phi)
dim_theta = len(gm_theta)
num_mic = dim_phi * dim_theta
dim_cf = len(cf)
# dimension:[control point, theta, phi]
theta = np.repeat(np.repeat(np.atleast_2d(gm_theta).T, dim_phi,
axis=1)[np.newaxis, :, :],
dim_alt,
axis=0)
phi = np.repeat(np.repeat(np.atleast_2d(gm_phi), dim_theta,
axis=0)[np.newaxis, :, :],
dim_alt,
axis=0)
altitude = np.repeat(np.repeat(np.atleast_2d(alt).T, dim_theta,
axis=1)[:, :, np.newaxis],
dim_phi,
axis=2)
x_vals = altitude / np.tan(theta)
y_vals = altitude / np.tan(phi)
z_vals = altitude
# store microphone locations
mic_locations = np.zeros((dim_alt, num_mic, 3))
mic_locations[:, :, 0] = x_vals.reshape(dim_alt, num_mic)
mic_locations[:, :, 1] = y_vals.reshape(dim_alt, num_mic)
mic_locations[:, :, 2] = z_vals.reshape(dim_alt, num_mic)
# append microphone locations to conditions
conditions.noise.microphone_theta_angles = gm_theta
conditions.noise.microphone_phi_angles = gm_phi
conditions.noise.microphone_locations = mic_locations
conditions.noise.number_of_microphones = num_mic
ctrl_pts = len(altitude)
# create empty arrays for results
num_src = len(config.propulsors) + 1
if ('lift_cruise') in config.propulsors.keys():
num_src += 1
source_SPLs_dBA = np.zeros((ctrl_pts, num_src, num_mic))
source_SPL_spectra = np.zeros((ctrl_pts, num_src, num_mic, dim_cf))
si = 1
# iterate through sources
for source in conditions.noise.sources.keys():
for network in config.propulsors.keys():
if source == 'turbofan':
geometric = noise_geometric(segment, analyses, config)
# flap noise - only applicable for turbofan aircraft
if 'flap' in config.wings.main_wing.control_surfaces:
airframe_noise = noise_airframe_Fink(
segment, analyses, config, settings)
source_SPLs_dBA[:, si, :] = airframe_noise.SPL_dBA
source_SPL_spectra[:, si, :, 5:] = np.repeat(
airframe_noise.SPL_spectrum[:, np.newaxis, :],
num_mic,
axis=1)
if bool(conditions.noise.sources[source].fan) and bool(
conditions.noise.sources[source].core):
config.propulsors[
source].fan.rotation = 0 # FUTURE WORK: NEED TO UPDATE ENGINE MODEL WITH FAN SPEED in RPM
config.propulsors[
source].fan_nozzle.noise_speed = conditions.noise.sources.turbofan.fan.exit_velocity
config.propulsors[
source].core_nozzle.noise_speed = conditions.noise.sources.turbofan.core.exit_velocity
engine_noise = noise_SAE(config.propulsors[source],
segment,
analyses,
config,
settings,
ioprint=print_flag)
source_SPLs_dBA[:, si, :] = np.repeat(
np.atleast_2d(engine_noise.SPL_dBA).T,
num_mic,
axis=1
) # noise measures at one microphone location in segment
source_SPL_spectra[:, si, :, 5:] = np.repeat(
engine_noise.SPL_spectrum[:, np.newaxis, :],
num_mic,
axis=1
) # noise measures at one microphone location in segment
elif (source == 'propeller') or (source == 'rotor'):
if bool(conditions.noise.sources[source]) == True:
net = config.propulsors[network]
prop = config.propulsors[network][source]
acoustic_data = conditions.noise.sources[source]
propeller_noise = propeller_mid_fidelity(
net, prop, acoustic_data, segment, settings)
source_SPLs_dBA[:, si, :] = propeller_noise.SPL_dBA
source_SPL_spectra[:,
si, :, :] = propeller_noise.SPL_spectrum
si += 1
conditions.noise.total_SPL_dBA = SPL_arithmetic(source_SPLs_dBA,
sum_axis=1)
return
def evaluate_noise(self, segment):
""" Process vehicle to setup geometry, condititon and configuration
Assumptions:
None
Source:
N/4
Inputs:
self.settings.
center_frequencies - 1/3 octave band frequencies [unitless]
Outputs:
None
Properties Used:
self.geometry
"""
# unpack
config = segment.analyses.noise.geometry
analyses = segment.analyses
settings = self.settings
print_flag = settings.print_noise_output
conditions = segment.state.conditions
dim_cf = len(settings.center_frequencies)
ctrl_pts = int(segment.state.numerics.number_control_points)
min_x = settings.level_ground_microphone_min_x
max_x = settings.level_ground_microphone_max_x
min_y = settings.level_ground_microphone_min_y
max_y = settings.level_ground_microphone_max_y
x_resolution = settings.level_ground_microphone_x_resolution
y_resolution = settings.level_ground_microphone_y_resolution
# generate noise valuation points
settings.ground_microphone_locations = generate_ground_microphone_points(
min_x, max_x, min_y, max_y, x_resolution, y_resolution)
GM_THETA, GM_PHI, GML, num_gm_mic = compute_ground_noise_evaluation_locations(
settings, segment)
BM_THETA, BM_PHI, UCML, num_b_mic = compute_building_noise_evaluation_locations(
settings, segment)
mic_locations = np.concatenate((GML, UCML), axis=1)
THETA = np.concatenate((GM_THETA, BM_THETA), axis=1)
PHI = np.concatenate((GM_PHI, BM_PHI), axis=1)
num_mic = num_b_mic + num_gm_mic
# append microphone locations to conditions
conditions.noise.ground_microphone_theta_angles = GM_THETA
conditions.noise.building_microphone_theta_angles = BM_THETA
conditions.noise.total_microphone_theta_angles = THETA
conditions.noise.ground_microphone_phi_angles = GM_PHI
conditions.noise.building_microphone_phi_angles = BM_PHI
conditions.noise.total_microphone_phi_angles = PHI
conditions.noise.ground_microphone_locations = GML
conditions.noise.building_microphone_locations = UCML
conditions.noise.total_microphone_locations = mic_locations
conditions.noise.number_ground_microphones = num_gm_mic
conditions.noise.number_building_microphones = num_b_mic
conditions.noise.total_number_of_microphones = num_mic
# create empty arrays for results
num_src = len(config.networks) + 1
if ('lift_cruise') in config.networks.keys():
num_src += 1
source_SPLs_dBA = np.zeros((ctrl_pts, num_src, num_mic))
source_SPL_spectra = np.zeros((ctrl_pts, num_src, num_mic, dim_cf))
si = 1
# iterate through sources
for source in conditions.noise.sources.keys():
for network in config.networks.keys():
if source == 'turbofan':
geometric = noise_geometric(segment, analyses, config)
# flap noise - only applicable for turbofan aircraft
if 'flap' in config.wings.main_wing.control_surfaces:
airframe_noise = noise_airframe_Fink(
segment, analyses, config, settings)
source_SPLs_dBA[:, si, :] = airframe_noise.SPL_dBA
source_SPL_spectra[:, si, :, 5:] = np.repeat(
airframe_noise.SPL_spectrum[:, np.newaxis, :],
num_mic,
axis=1)
if bool(conditions.noise.sources[source].fan) and bool(
conditions.noise.sources[source].core):
config.networks[
source].fan.rotation = 0 # FUTURE WORK: NEED TO UPDATE ENGINE MODEL WITH FAN SPEED in RPM
config.networks[
source].fan_nozzle.noise_speed = conditions.noise.sources.turbofan.fan.exit_velocity
config.networks[
source].core_nozzle.noise_speed = conditions.noise.sources.turbofan.core.exit_velocity
engine_noise = noise_SAE(config.networks[source],
segment,
analyses,
config,
settings,
ioprint=print_flag)
source_SPLs_dBA[:, si, :] = np.repeat(
np.atleast_2d(engine_noise.SPL_dBA).T,
num_mic,
axis=1
) # noise measures at one microphone location in segment
source_SPL_spectra[:, si, :, 5:] = np.repeat(
engine_noise.SPL_spectrum[:, np.newaxis, :],
num_mic,
axis=1
) # noise measures at one microphone location in segment
elif (source == 'propellers') or (source == 'lift_rotors'):
if bool(conditions.noise.sources[source]) == True:
net = config.networks[network]
acoustic_data = conditions.noise.sources[source]
propeller_noise = propeller_mid_fidelity(
net, acoustic_data, segment, settings, source)
source_SPLs_dBA[:, si, :] = propeller_noise.SPL_dBA
source_SPL_spectra[:,
si, :, :] = propeller_noise.SPL_spectrum
si += 1
conditions.noise.total_SPL_dBA = SPL_arithmetic(source_SPLs_dBA,
sum_axis=1)
return