Viscosity

from tkinter import *
import math
tk=Tk()
WIDTH=5000
HEIGHT=400
canvas=Canvas(tk,width=WIDTH,height=HEIGHT)
tk.title('Viscosity')
canvas.pack()


dt=.0001
u=500
VEL1=10000
VEL2=0
p=0
w=.05
AMP=30000


class Layer():
    def __init__(self,posy):
        self.shape=canvas.create_rectangle(0,posy,10,posy+10,fill='blue')
        self.vel=0
    def move(self,above,below,vel,i,t):
        acc=p+u*((above-vel)+(below-vel))
        self.vel+=acc*dt
        if i==0:
            self.vel=VEL1
        if i==len(layers)-1:
            self.vel=VEL2
        canvas.move(self.shape,self.vel*dt,0)
        
        
layers=[]
for x in range(40):
    layers.append(Layer(x*10))

for x in range(10000):
    for i in range(len(layers)):
        if i==0:
            above=layers[i].vel
        else:
            above=layers[i-1].vel 
        if i==len(layers)-1:
            below=layers[i].vel
        else:
            below=layers[i+1].vel
        vel=layers[i].vel
        layers[i].move(above,below,vel,i,x)
    tk.update()
tk.mainloop()