turbulentBC.py

"""
calculation code for turbulence initial condition
"""

import numpy as np
import matplotlib.pyplot as plt
import scipy.interpolate as interpolate

class Water:
    def __init__(self,temp):
        if temp >40 or temp <-10: print("temp. range of air is between 0 and 50 -C\n")
        self._temp = temp
        self._table = np.array([0, 10, 20, 30, 40, 50]) # [-C]
        self._rho = np.array([999.89, 999.69, 998.22, 995.67, 992.24, 988.02]) # [kg/m3]
        self._mu = np.array([1.729e-3, 1.307e-3, 1.004e-3, 0.801e-3, 0.658e-3, 0.554e-3]) #[Pa-s]
    def rho(self):
        func_rho = interpolate.interp1d(self._table, self._rho, kind='cubic')
        return func_rho(self._temp)
    def mu(self):
        func_mu = interpolate.interp1d(self._table, self._mu, kind='cubic')
        return func_mu(self._temp)
    def nu(self):
        return self.mu()/self.rho()

class Air:
    def __init__(self,temp):
        if temp >40 or temp <-10: print("temp. range of air is between -10 and 40 -C\n")
        self._temp = temp
        self._table = np.array([-10, 0, 10, 20, 30, 40]) #[-C]
        self._rho = np.array([1.342, 1.293, 1.247, 1.205, 1.165, 1.128]) #[kg/m3]
        self._mu = np.array([1.673e-5, 1.724e-5, 1.772e-5, 1.822e-5, 1.869e-5, 1.915e-5]) #[Pa-s]
    def rho(self):
        func_rho = interpolate.interp1d(self._table, self._rho, kind='cubic')
        return func_rho(self._temp)
    def mu(self):
        func_mu = interpolate.interp1d(self._table, self._mu, kind='cubic')
        return func_mu(self._temp)
    def nu(self):
        return self.mu()/self.rho()

# +*+*+*+*
tIntensity = 0.05 # turbulent intensity [-]
cmu = 0.09
U = 0.04568 # [m/s]
cLength = 1.0 # characteristic length [m]
# +*+*+*+*

# air = Air(20)
water = Water(20)
rho = water.rho()
mu = water.mu()

tKineticEnergy = 3.0/2.0 * pow(U*tIntensity, 2.0)
mLength = 0.07 * cLength # mixing length
epsilon = pow(tKineticEnergy,3/2) * pow(tKineticEnergy, 3/2) / mLength
omega = pow(tKineticEnergy, 1/2) / pow(cmu, 1/4) / mLength

print(tKineticEnergy, epsilon)