def testIntegrationWithKandlikarRelation(self):
# Same test but only focussing on Nusselt number for Kandlikar relation, as that would prove thar arguments are correctly passed to function
td = thrusters.thruster_data.td_verification_one # Dummy dictionary with thruster data for verifcation
Nu_func_gas = thermo.convection.Nu_DB
Nu_func_liquid = thermo.convection.Nu_Kandlikar_NDB_Re_low_sat_gas_constant_wall_temp_square_water
T_wall = td['T_wall']
w_channel = td['w_channel']
T_inlet = td['T_inlet']
T_chamber = td['T_chamber']
p_ref = td['p_inlet']
m_dot = td['m_dot']
h_channel = td['h_channel']
fp = FluidProperties(td['propellant'])
# Check just the liquid/multi-phase Nusselt number of the Kandlikar relation, to ensure integration is correct
exp_Nu_liquid_multi = 46.74856022286813
res = zD.two_phase_single_channel(
T_wall=T_wall,
w_channel=w_channel,
Nu_func_gas=Nu_func_gas,
Nu_func_liquid=Nu_func_liquid,
T_inlet=T_inlet,
T_chamber=T_chamber,
p_ref=p_ref,
m_dot=m_dot,
h_channel=h_channel,
fp=fp,
print_info=False)
self.assertAlmostEqual(exp_Nu_liquid_multi, res['Nu_liquid_multi'], delta=0.01*exp_Nu_liquid_multi)
import thrusters.thruster_data
import thermo.convection
from thermo.prop import FluidProperties
td = thrusters.thruster_data.td_Silva_5 # Dictionary with design/measured values
Nu_func_gas = thermo.convection.Nu_DB # [-] Function to calculate Nusselt number
Nu_func_liquid = thermo.convection.Nu_DB
#bla
# For da Silva's thrusters the numbers have to fudged a bit, because the reported temperatures
# seem inconsitent with saturation temperatures and/or reported wall temperatures
T_wall = td['T_wall'] +50 # [K] Wall temperature
w_channel = td['w_channel'] # [m] Channel width
T_inlet = td['T_inlet'] # [K] Inlet temperature
T_chamber = td['T_chamber']+1 # [K] Chamber temperature
p_inlet = td['p_inlet'] # [Pa] Inlet pressure
m_dot = td['m_dot'] # [kg/s] Mass flow (through all channels if multiple)
channel_amount = td['channel_amount'] # [-] Amount of channels
h_channel = td['h_channel'] # [m] Channel height/depth
fp = FluidProperties(td['propellant']) # Object from which fluid properties can be accessed
# Calculate mass flow for one single channel
m_dot_channel = m_dot/channel_amount # [kg/s] Mass flow through one single channel
zD.two_phase_single_channel( T_wall=T_wall, w_channel=w_channel, Nu_func_gas=Nu_func_gas, Nu_func_liquid=Nu_func_liquid,\
T_inlet=T_inlet, T_chamber=T_chamber, p_ref=p_inlet, m_dot=m_dot_channel,\
h_channel=h_channel, fp=fp)
# Calculate mass flow for one single channel
m_dot_channel = m_dot / channel_amount # [kg/s] Mass flow through one single channel
## Wall temperature is unknown so a range is chosen instead:
T_wall = np.linspace(start=T_chamber + 1, stop=700, num=250) # [K]
it = np.nditer(T_wall, flags=['c_index'])
L_channel_1 = np.zeros_like(T_wall) # [m]
L_channel_2 = np.zeros_like(T_wall) # [m]
L_channel_3 = np.zeros_like(T_wall) # [m]
for T in it:
## First set of Nusselt relations
res_1 = zD.two_phase_single_channel( T_wall=T, w_channel=w_channel, Nu_func_gas=Nu_func_gas_1, Nu_func_liquid=Nu_func_liquid_1,\
T_inlet=T_inlet, T_chamber=T_chamber, p_ref=p_inlet, m_dot=m_dot_channel,\
h_channel=h_channel, fp=fp,print_info=False)
# Store results
L_channel_1[it.index] = res_1['L_channel']
## Second set of Nusselt relations
res_2 = zD.two_phase_single_channel( T_wall=T, w_channel=w_channel, Nu_func_gas=Nu_func_gas_2, Nu_func_liquid=Nu_func_liquid_2,\
T_inlet=T_inlet, T_chamber=T_chamber, p_ref=p_inlet, m_dot=m_dot_channel,\
h_channel=h_channel, fp=fp,print_info=False)
# Store results
L_channel_2[it.index] = res_2['L_channel']
## Third set of Nusselt relations
res_3 = zD.two_phase_single_channel( T_wall=T, w_channel=w_channel, Nu_func_gas=Nu_func_gas_3, Nu_func_liquid=Nu_func_liquid_3,\
T_inlet=T_inlet, T_chamber=T_chamber, p_ref=p_inlet, m_dot=m_dot_channel,\
h_channel=h_channel, fp=fp,print_info=False)
def testDummyWithWebBookData(self):
td = thrusters.thruster_data.td_verification_one # Dummy dictionary with thruster data for verifcation
Nu_func_gas = thermo.convection.Nu_DB
Nu_func_liquid = thermo.convection.Nu_DB
T_wall = td['T_wall']
w_channel = td['w_channel']
T_inlet = td['T_inlet']
T_chamber = td['T_chamber']
p_ref = td['p_inlet']
m_dot = td['m_dot']
h_channel = td['h_channel']
fp = FluidProperties(td['propellant'])
# Expected values for liquid and multi/phase portion of channel
exp_Q_dot_liquid_multi = 2.635 # [W]
exp_T_bulk_liquid_multi = 362.49 # [K]
exp_u_bulk_liquid_multi = 0.1035271 # [m/s]
exp_rho_bulk_liquid_multi = 965.93 # [kg/m^3]
exp_Re_liquid_multi = 31.5556 # [-]
exp_Pr_liquid_multi = 1.973033 # [-]
exp_Nu_liquid_multi = 0.4775 # [-]
exp_St_liquid_multi = 0.00767 # [-]
exp_h_conv_liquid_multi = 3224.5 # [W/(m^2*K)]
exp_A_heater_liquid_multi = 3.4407e-6 # [m^2]
exp_L_channel_liquid_multi = 0.0086018 # [m]
# Expected values for gas portion of channel
exp_Q_dot_gas = 0.1646 # [W]
exp_T_bulk_gas = 462.49 # [K]
exp_u_bulk_gas = 41.423 # [m/2]
exp_rho_bulk_gas = 2.4141 # [kg/m^3]
exp_Re_bulk_gas = 640.70 # [-]
exp_Pr_bulk_gas = 0.99236 # [-]
exp_Nu_gas = 4.0338 # [-]
exp_St_gas = 0.0063444 # [-]
exp_h_conv_gas = 1377.4 # [W/(m^2*K)]
exp_A_heater_gas = 8.6903e-7 # [m^2]
exp_L_channel_gas = 2.1726e-3 # [m]
# Expected value for total
exp_L_channel = 10.774e-3 # [m]
res = zD.two_phase_single_channel(
T_wall=T_wall,
w_channel=w_channel,
Nu_func_gas=Nu_func_gas,
Nu_func_liquid=Nu_func_liquid,
T_inlet=T_inlet,
T_chamber=T_chamber,
p_ref=p_ref,
m_dot=m_dot,
h_channel=h_channel,
fp=fp,
print_info=False)
# Checking liquid/multi-phase results
self.assertAlmostEqual(exp_Q_dot_liquid_multi, res['Q_dot_liquid_multi'], delta=0.001*exp_Q_dot_liquid_multi)
self.assertAlmostEqual(exp_T_bulk_liquid_multi, res['T_bulk_liquid_multi'], delta=0.001*exp_T_bulk_liquid_multi)
self.assertAlmostEqual(exp_rho_bulk_liquid_multi, res['rho_bulk_liquid_multi'], delta=0.001*exp_rho_bulk_liquid_multi)
self.assertAlmostEqual(exp_u_bulk_liquid_multi, res['u_bulk_liquid_multi'], delta=0.001*exp_u_bulk_liquid_multi)
self.assertAlmostEqual(exp_Re_liquid_multi, res['Re_bulk_liquid_multi'], delta=0.001*exp_Re_liquid_multi)
self.assertAlmostEqual(exp_Pr_liquid_multi, res['Pr_bulk_liquid_multi'], delta=0.01*exp_Pr_liquid_multi)
self.assertAlmostEqual(exp_Nu_liquid_multi, res['Nu_liquid_multi'], delta=0.01*exp_Nu_liquid_multi)
self.assertAlmostEqual(exp_St_liquid_multi, res['St_liquid_multi'], delta=0.01*exp_St_liquid_multi)
self.assertAlmostEqual(exp_h_conv_liquid_multi, res['h_conv_liquid_multi'], delta=0.01*exp_h_conv_liquid_multi)
self.assertAlmostEqual(exp_A_heater_liquid_multi, res['A_heater_liquid_multi'], delta=0.01*exp_A_heater_liquid_multi)
self.assertAlmostEqual(exp_L_channel_liquid_multi, res['L_channel_liquid_multi'], delta=0.01*exp_L_channel_liquid_multi)
# Again, but for gas phase
self.assertAlmostEqual(exp_Q_dot_gas, res['Q_dot_gas'], delta=0.001*exp_Q_dot_gas)
self.assertAlmostEqual(exp_T_bulk_gas, res['T_bulk_gas'], delta=0.001*exp_T_bulk_gas)
self.assertAlmostEqual(exp_u_bulk_gas, res['u_bulk_gas'], delta=0.001*exp_u_bulk_gas)
self.assertAlmostEqual(exp_rho_bulk_gas, res['rho_bulk_gas'], delta=0.001*exp_rho_bulk_gas)
self.assertAlmostEqual(exp_Re_bulk_gas, res['Re_bulk_gas'], delta=0.001*exp_Re_bulk_gas)
self.assertAlmostEqual(exp_Pr_bulk_gas, res['Pr_bulk_gas'], delta=0.013*exp_Pr_bulk_gas)
self.assertAlmostEqual(exp_Nu_gas, res['Nu_gas'], delta=0.01*exp_Nu_gas)
self.assertAlmostEqual(exp_St_gas, res['St_gas'], delta=0.01*exp_St_gas)
self.assertAlmostEqual(exp_h_conv_gas, res['h_conv_gas'], delta=0.01*exp_h_conv_gas)
self.assertAlmostEqual(exp_A_heater_gas, res['A_heater_gas'], delta=0.01*exp_A_heater_gas)
self.assertAlmostEqual(exp_L_channel_gas, res['L_channel_gas'], delta=0.01*exp_L_channel_gas)
# Checking the total
self.assertAlmostEqual(exp_L_channel, res['L_channel'], delta = 0.01*exp_L_channel)