import numpy as np
from pyro.mesh import patch
from pyro.util import msg
[docs]
def init_data(my_data, rp):
""" initialize the Kelvin-Helmholtz problem """
msg.bold("initializing the Kelvin-Helmholtz problem...")
# make sure that we are passed a valid patch object
if not isinstance(my_data, patch.CellCenterData2d):
print(my_data.__class__)
msg.fail("ERROR: patch invalid in kh.py")
# get the heightity, momenta, and energy as separate variables
height = my_data.get_var("height")
xmom = my_data.get_var("x-momentum")
ymom = my_data.get_var("y-momentum")
X = my_data.get_var("fuel")
# initialize the components, remember, that ener here is h*eint
# + 0.5*h*v**2, where eint is the specific internal energy
# (erg/g)
height[:, :] = 1.0
xmom[:, :] = 0.0
ymom[:, :] = 0.0
h_1 = rp.get_param("kh.h_1")
v_1 = rp.get_param("kh.v_1")
h_2 = rp.get_param("kh.h_2")
v_2 = rp.get_param("kh.v_2")
myg = my_data.grid
dy = 0.025
w0 = 0.01
vm = 0.5*(v_1 - v_2)
hm = 0.5*(h_1 - h_2)
idx1 = myg.y2d < 0.25
idx2 = np.logical_and(myg.y2d >= 0.25, myg.y2d < 0.5)
idx3 = np.logical_and(myg.y2d >= 0.5, myg.y2d < 0.75)
idx4 = myg.y2d >= 0.75
# we will initialize momemum as velocity for now
# lower quarter
height[idx1] = h_1 - hm*np.exp((myg.y2d[idx1] - 0.25)/dy)
xmom[idx1] = v_1 - vm*np.exp((myg.y2d[idx1] - 0.25)/dy)
X[idx1] = 1 - 0.5*np.exp((myg.y2d[idx1] - 0.25)/dy)
# second quarter
height[idx2] = h_2 + hm*np.exp((0.25 - myg.y2d[idx2])/dy)
xmom[idx2] = v_2 + vm*np.exp((0.25 - myg.y2d[idx2])/dy)
X[idx2] = 0.5*np.exp((0.25 - myg.y2d[idx2])/dy)
# third quarter
height[idx3] = h_2 + hm*np.exp((myg.y2d[idx3] - 0.75)/dy)
xmom[idx3] = v_2 + vm*np.exp((myg.y2d[idx3] - 0.75)/dy)
X[idx3] = 0.5*np.exp((myg.y2d[idx3] - 0.75)/dy)
# fourth quarter
height[idx4] = h_1 - hm*np.exp((0.75 - myg.y2d[idx4])/dy)
xmom[idx4] = v_1 - vm*np.exp((0.75 - myg.y2d[idx4])/dy)
X[idx4] = 1 - 0.5*np.exp((0.75 - myg.y2d[idx4])/dy)
# upper half
xmom[:, :] *= height
ymom[:, :] = height * w0 * np.sin(4*np.pi*myg.x2d)
X[:, :] *= height
[docs]
def finalize():
""" print out any information to the user at the end of the run """