def loss_at_an_abrupt_contraction_in_circular_tubing(temperature=293.15, # Kelvin
pressure=101.3, # kPa
particle_diameter=1, # µm
particle_density=1000, # kg/m^3
tube_air_velocity=False, # m/s
flow_rate_in_inlet=3, # cc/s
tube_diameter=0.0025, # m
contraction_diameter=0.00125, # m
contraction_angle=90, # degrees
verbose=False,
):
"""
(B&W 8-69 to 8-71; W&B 6-54, 17-25)
Temperature 293.15 Kelvin
Pressure 101.3 kPa
Particle diameter 1 µm
Particle density 1000 kg/m^3
Tube air velocity 10 m/s
Tube diameter 0.0025 m
Contraction diameter 0.00125 m
Contraction angle 90 degrees
"""
if not tube_air_velocity:
tube_air_velocity = tools.flow_rate2flow_velocity(flow_rate_in_inlet, tube_diameter, verbose=verbose)
st_num = tools.stokes_number(particle_density, particle_diameter, pressure, temperature, tube_air_velocity, 1,
contraction_diameter, verbose=verbose)
# st_num = (particle_density * particle_diameter * particle_diameter * 0.000000000001 * slip_correction_factor * B906 / (18*B912*B908))
frac = 1 - (1 / (1 + ((2 * st_num * (1 - (contraction_diameter / tube_diameter) ** 2)) / (
3.14 * np.exp(-0.0185 * contraction_angle))) ** -1.24))
return frac
def aspiration_efficiency_all_forward_angles(temperature=293.15, # Kelvin
pressure=101.3, # kPa
particle_diameter=10, # µm
particle_density=1000, # kg/m^3
inlet_diameter=0.025, # m
sampling_angle=46, # degrees between 0 to 90°
flow_rate_in_inlet=3, # cc/s
air_velocity_in_inlet=False, # m/s
velocity_ratio=5, # R is 1 for isokinetic, > 1 for subisokinetic
force=False,
verbose=False):
"""
(B&W 8-20, 8-21, 8-22; W&B 6-20, 6-21, 6-22)
Hangal and Willeke Eviron. Sci. Tech. 24:688-691 (1990)
Temperature 293.15 Kelvin
Pressure 101.3 kPa
Particle diameter 10 µm
Particle density 1000 kg/m^3
Inlet diameter 0.025 m
Sampling angle 46 degrees between 0 to 90°
Air velocity in inlet (Vi) 0.34 m/s
Velocity ratio (Vw/Vi) 5 R is 1 for isokinetic, > 1 for subisokinetic
"""
if not air_velocity_in_inlet:
air_velocity_in_inlet = tools.flow_rate2flow_velocity(flow_rate_in_inlet, inlet_diameter, verbose=verbose)
st_num = tools.stokes_number(particle_density, particle_diameter, pressure, temperature, air_velocity_in_inlet,
velocity_ratio, inlet_diameter, verbose=verbose)
# rey_num = tools.flow_reynolds_number(inlet_diameter, air_velocity_in_inlet, temperature, pressure, verbose=verbose)
if (45 < sampling_angle <= 90) and (1.25 < velocity_ratio < 6.25) and (0.003 < st_num < 0.2):
pass
else:
txt = """sampling angle, velocity ratio, or stokes number is not in valid regime!
Sampling angle: %s (45 < angle < 90)
Velocity ratio: %s (1.25 < ratio < 6.25)
Stokes number: %s (0.003 < st_num < 0.2)""" % (sampling_angle, velocity_ratio, st_num)
if force:
warnings.warn(txt)
else:
raise ValueError(txt)
if sampling_angle == 0:
inert_param = 1 - 1 / (1 + (2 + 0.617 / velocity_ratio) * st_num)
elif sampling_angle > 45:
inert_param = 3 * st_num ** (velocity_ratio ** -0.5)
else:
f619 = st_num * np.exp(0.022 * sampling_angle)
inert_param = (1 - 1 / (1 + (2 + 0.617 / velocity_ratio) * f619)) * (
1 - 1 / (1 + 0.55 * f619 * np.exp(0.25 * f619))) / (1 - 1 / (1 + 2.617 * f619))
# =IF(B609=0,1-1/(1+(2+0.617/B611)*B618),IF(B609>45,3*B618^(B611^-0.5),(1-1/(1+(2+0.617/B611)*B619))*(1-1/(1+0.55*B619*EXP(0.25*B619)))/(1-1/(1+2.617*B619))))
asp_eff = 1 + (velocity_ratio * np.cos(sampling_angle * np.pi / 180) - 1) * inert_param
return asp_eff
def loss_in_a_bent_section_of_circular_tubing(
temperature=293.15, # Kelvin
pressure=101.3, # kPa
particle_diameter=3.5, # µm
particle_density=1000, # kg/m^3
tube_air_flow_rate=3, # cc/s
tube_air_velocity=False, # m/s
tube_diameter=0.0025, # m
angle_of_bend=90, # degrees
flow_type='auto',
verbose=False):
""" (B&W 8-66 to 8-68; W&B 6-52, 6-53)
Temperature 293.15 Kelvin
Pressure 101.3 kPa
Particle Diameter 3.5 µm
Particle Density 1000 kg/m^3
Tube air velocity 6.25 m/s
Tube diameter 0.0025 m
Angle of bend 90 degrees"""
if not tube_air_velocity:
tube_air_velocity = tools.flow_rate2flow_velocity(tube_air_flow_rate,
tube_diameter,
verbose=verbose)
if flow_type == 'auto':
flow_type = tools.test_flow_type_in_tube(tube_diameter,
tube_air_velocity,
temperature,
pressure,
verbose=verbose)
velocity_ratio = 1
stnum = tools.stokes_number(particle_density,
particle_diameter,
pressure,
temperature,
tube_air_velocity,
velocity_ratio,
tube_diameter,
verbose=verbose)
if flow_type == 'laminar':
fract = 1 - stnum * angle_of_bend * np.pi / 180.
elif flow_type == 'turbulent':
fract = np.exp(-2.823 * stnum * angle_of_bend * np.pi / 180)
else:
raise ValueError('Unknown flow type: %s' % flow_type)
return fract
def loss_at_an_abrupt_contraction_in_circular_tubing(
temperature=293.15, # Kelvin
pressure=101.3, # kPa
particle_diameter=1, # µm
particle_density=1000, # kg/m^3
tube_air_velocity=False, # m/s
flow_rate_in_inlet=3, # cc/s
tube_diameter=0.0025, # m
contraction_diameter=0.00125, # m
contraction_angle=90, # degrees
verbose=False,
):
"""
(B&W 8-69 to 8-71; W&B 6-54, 17-25)
Temperature 293.15 Kelvin
Pressure 101.3 kPa
Particle diameter 1 µm
Particle density 1000 kg/m^3
Tube air velocity 10 m/s
Tube diameter 0.0025 m
Contraction diameter 0.00125 m
Contraction angle 90 degrees
"""
if not tube_air_velocity:
tube_air_velocity = tools.flow_rate2flow_velocity(flow_rate_in_inlet,
tube_diameter,
verbose=verbose)
st_num = tools.stokes_number(particle_density,
particle_diameter,
pressure,
temperature,
tube_air_velocity,
1,
contraction_diameter,
verbose=verbose)
# st_num = (particle_density * particle_diameter * particle_diameter * 0.000000000001 * slip_correction_factor * B906 / (18*B912*B908))
frac = 1 - (1 / (1 +
((2 * st_num *
(1 - (contraction_diameter / tube_diameter)**2)) /
(3.14 * np.exp(-0.0185 * contraction_angle)))**-1.24))
return frac
def loss_in_a_bent_section_of_circular_tubing(temperature=293.15, # Kelvin
pressure=101.3, # kPa
particle_diameter=3.5, # µm
particle_density=1000, # kg/m^3
tube_air_flow_rate=3, # cc/s
tube_air_velocity=False, # m/s
tube_diameter=0.0025, # m
angle_of_bend=90, # degrees
flow_type='auto',
verbose=False
):
""" (B&W 8-66 to 8-68; W&B 6-52, 6-53)
Temperature 293.15 Kelvin
Pressure 101.3 kPa
Particle Diameter 3.5 µm
Particle Density 1000 kg/m^3
Tube air velocity 6.25 m/s
Tube diameter 0.0025 m
Angle of bend 90 degrees"""
if not tube_air_velocity:
tube_air_velocity = tools.flow_rate2flow_velocity(tube_air_flow_rate, tube_diameter, verbose=verbose)
if flow_type == 'auto':
flow_type = tools.test_flow_type_in_tube(tube_diameter, tube_air_velocity, temperature, pressure,
verbose=verbose)
velocity_ratio = 1
stnum = tools.stokes_number(particle_density, particle_diameter, pressure, temperature, tube_air_velocity,
velocity_ratio, tube_diameter, verbose=verbose)
if flow_type == 'laminar':
fract = 1 - stnum * angle_of_bend * np.pi / 180.
elif flow_type == 'turbulent':
fract = np.exp(-2.823 * stnum * angle_of_bend * np.pi / 180)
else:
raise ValueError('Unknown flow type: %s' % flow_type)
return fract
def aspiration_efficiency_all_forward_angles(
temperature=293.15, # Kelvin
pressure=101.3, # kPa
particle_diameter=10, # µm
particle_density=1000, # kg/m^3
inlet_diameter=0.025, # m
sampling_angle=46, # degrees between 0 to 90°
flow_rate_in_inlet=3, # cc/s
air_velocity_in_inlet=False, # m/s
velocity_ratio=5, # R is 1 for isokinetic, > 1 for subisokinetic
force=False,
verbose=False):
"""
(B&W 8-20, 8-21, 8-22; W&B 6-20, 6-21, 6-22)
Hangal and Willeke Eviron. Sci. Tech. 24:688-691 (1990)
Temperature 293.15 Kelvin
Pressure 101.3 kPa
Particle diameter 10 µm
Particle density 1000 kg/m^3
Inlet diameter 0.025 m
Sampling angle 46 degrees between 0 to 90°
Air velocity in inlet (Vi) 0.34 m/s
Velocity ratio (Vw/Vi) 5 R is 1 for isokinetic, > 1 for subisokinetic
"""
if not air_velocity_in_inlet:
air_velocity_in_inlet = tools.flow_rate2flow_velocity(
flow_rate_in_inlet, inlet_diameter, verbose=verbose)
st_num = tools.stokes_number(particle_density,
particle_diameter,
pressure,
temperature,
air_velocity_in_inlet,
velocity_ratio,
inlet_diameter,
verbose=verbose)
# rey_num = tools.flow_reynolds_number(inlet_diameter, air_velocity_in_inlet, temperature, pressure, verbose=verbose)
if (45 < sampling_angle <= 90) and (1.25 < velocity_ratio <
6.25) and (0.003 < st_num < 0.2):
pass
else:
txt = """sampling angle, velocity ratio, or stokes number is not in valid regime!
Sampling angle: %s (45 < angle < 90)
Velocity ratio: %s (1.25 < ratio < 6.25)
Stokes number: %s (0.003 < st_num < 0.2)""" % (sampling_angle, velocity_ratio,
st_num)
if force:
warnings.warn(txt)
else:
raise ValueError(txt)
if sampling_angle == 0:
inert_param = 1 - 1 / (1 + (2 + 0.617 / velocity_ratio) * st_num)
elif sampling_angle > 45:
inert_param = 3 * st_num**(velocity_ratio**-0.5)
else:
f619 = st_num * np.exp(0.022 * sampling_angle)
inert_param = (1 - 1 / (1 + (2 + 0.617 / velocity_ratio) * f619)) * (
1 - 1 /
(1 + 0.55 * f619 * np.exp(0.25 * f619))) / (1 - 1 /
(1 + 2.617 * f619))
# =IF(B609=0,1-1/(1+(2+0.617/B611)*B618),IF(B609>45,3*B618^(B611^-0.5),(1-1/(1+(2+0.617/B611)*B619))*(1-1/(1+0.55*B619*EXP(0.25*B619)))/(1-1/(1+2.617*B619))))
asp_eff = 1 + (velocity_ratio * np.cos(sampling_angle * np.pi / 180) -
1) * inert_param
return asp_eff
