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In [2]:

%pylab inline

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Populating the interactive namespace from numpy and matplotlib

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In [3]:

# Constants
density_air = 0.856e-3 # g cm^-3
density_water = 1 # g cm^-3
density_mist = 1e-6 # g cm^-3
viscosity = 0.206 # cm^2 s^-1 This is the kinematic viscosity
g = 0.0981 #cm s^-2

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In [4]:

# Parameters
epsilon = (density_mist/density_water)/2
sigma = ((8/81)*(g**2/viscosity)*(density_water/density_air)**2)**(1/3)

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Consider the raindrop's behaviour without the mist drag.

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In [5]:

# Initial Conditions
init_radius = 0.01 # cm
init_velocity = 0 # cm s^-1
time_step  = 0.001
end_time = 10.

time_list = arange(0,end_time,time_step)
vel_list = empty_like(time_list) # Initially at rest
vel_list[0] = init_velocity

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In [6]:

def f(velocity):

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In [7]:

for index in range(1,vel_list.shape[0]):
vel_list[index] = vel_list[index-1] + f(vel_list[index-1])*time_step

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In [8]:

plot(time_list,vel_list)

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Out[8]:

[<matplotlib.lines.Line2D at 0x152bd29a668>]

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In [38]:

time_list = arange(0,end_time,time_step)
vel_list = empty_like(radius_list) # Initially at rest
vel_list[0] = init_vel_list

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In [39]:

for index in range(1,vel_list.shape[0]):
vel_list[index,:] = vel_list[index-1,:] + f(vel_list[index-1,:],radius_list[index-1,:])*time_step

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In [44]:

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Out[44]:

[<matplotlib.lines.Line2D at 0x152bfcf6780>]

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In [43]:

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Out[43]:

[<matplotlib.lines.Line2D at 0x152bfc62588>]

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In [ ]: