#!/usr/bin/env python
# encoding: utf-8

# 3 pairs of spheres with different diameters,
# different capillary bridge models and different
# bridge volume are pulled out and the capillary forces
# are messed after 250 iterations and compared to a
# verified values (TODO: values check one more time).

# Links to papers:
# Comparison of different capillary bridge models for application in the discrete element method
# (A. Gladkyy, R. Schwarze)
# http://arxiv.org/pdf/1403.7926.pdf

# Capillary forces between surfaces with nanoscale roughness (Yakov I. Rabinovich ...)
# http://diyhpl.us/~bryan/papers2/Capillary%20forces%20between%20surfaces%20with%20nanoscale%20roughness.pdf

from yade import plot

o = Omega()
fr = 0.5
rho = 2000
tc = 0.001
en = 0.7
et = 0.7
o.dt = 0.001 * tc

tolerance = 0.0001

r0 = 19.0e-6
r1 = 35.0e-6
r2 = 32.5e-6
r3 = 27.5e-6

Gamma1 = 27.0e-3
Gamma2 = 24.0e-3
Gamma3 = 28.0e-3

Theta = 10.0

VB1 = 2.0e-19
VB2 = 12.0e-19
VB3 = 36.0e-19

CapillarType1 = "Willett_numeric"
CapillarType2 = "Willett_analytic"
CapillarType3 = "Rabinovich"

mat1 = O.materials.append(
        ViscElCapMat(frictionAngle=fr, density=rho, Vb=VB1, gamma=Gamma1, theta=Theta, Capillar=True, CapillarType=CapillarType1, tc=tc, en=en, et=et)
)
mat2 = O.materials.append(
        ViscElCapMat(frictionAngle=fr, density=rho, Vb=VB2, gamma=Gamma2, theta=Theta, Capillar=True, CapillarType=CapillarType2, tc=tc, en=en, et=et)
)
mat3 = O.materials.append(
        ViscElCapMat(frictionAngle=fr, density=rho, Vb=VB3, gamma=Gamma3, theta=Theta, Capillar=True, CapillarType=CapillarType3, tc=tc, en=en, et=et)
)

id1 = O.bodies.append(sphere(center=[0, 0, 0], radius=r0, material=mat1, fixed=True))
id2 = O.bodies.append(sphere(center=[0, 0, (r0 + r1) * 0.99999], radius=r1, material=mat1, fixed=True))

id3 = O.bodies.append(sphere(center=[3.0 * r1, 0, 0], radius=r0, material=mat2, fixed=True))
id4 = O.bodies.append(sphere(center=[3.0 * r1, 0, (r0 + r2) * 0.99999], radius=r2, material=mat2, fixed=True))

id5 = O.bodies.append(sphere(center=[6.0 * r1, 0, 0], radius=r0, material=mat3, fixed=True))
id6 = O.bodies.append(sphere(center=[6.0 * r1, 0, (r0 + r3) * 0.99999], radius=r3, material=mat3, fixed=True))

o.engines = [
        ForceResetter(),
        InsertionSortCollider([Bo1_Sphere_Aabb()], verletDist=(r0 + r1) * 5.0),
        InteractionLoop(
                [Ig2_Sphere_Sphere_ScGeom()],
                [Ip2_ViscElCapMat_ViscElCapMat_ViscElCapPhys()],
                [Law2_ScGeom_ViscElCapPhys_Basic()],
        ),
        NewtonIntegrator(damping=0, gravity=[0, 0, 0]),
]

O.bodies[id2].state.vel = [0, 0, 0.001]
O.bodies[id4].state.vel = [0, 0, 0.001]
O.bodies[id6].state.vel = [0, 0, 0.001]

O.run(250, True)

f1 = -O.forces.f(id2)[2]
f2 = -O.forces.f(id4)[2]
f3 = -O.forces.f(id6)[2]
O.wait()

if ((abs(2.07328148666e-07 - f1) / f1) > tolerance):
	raise YadeCheckError("error 1")

if ((abs(6.78192074e-07 - f2) / f2) > tolerance):
	raise YadeCheckError("error 2")

if ((abs(1.58617796928e-06 - f3) / f3) > tolerance):
	raise YadeCheckError("error 3")
