#
# Enforced Velocity Test
#
# Problem description
# An elastic steel rod has the velocity of one of its ends increased
# from 0 to 1 m/s at time zero and thereafter held constant.
# The rod is otherwise unconstrained
#
# Model description
# One rod_2 element is used to model the rod.
# The timestep is scaled by 0.05 to ensure that oscillation should not
# make the solution unstable.
#
# Engineering data
# Density = 7850 kg/m3
# Youngs modulus = 210E9 N/m2
# Poissons ratio = 0.3
# Rod Section Area = 1 m2
#
# Reference results
# Node 1 should move with a constant velocity of 1 m/s
# The rod should have a cyclic velocity with a mean value of 1 m/s, an
# amplitude of 1 m/s and a period of 0.77E-3 s according to:
#
# Sound speed = sqrt(Youngs_modulus/density) = 5172 m/s
# Time for a sound wave to pass along a rod = 1/5172 = 0.193E-3 s
# Time for one period = 4*0.193E9 = 0.77E-3 s
#
# Comparisons of results
# Node 1 has a constant velocity of 1 m/s which corresponds with
# theory.
# Node 2 results:
#
# MSC-Dyna Impact Theory
# amplitude 1.0 1.0 1.0
# period 0.00086 0.00086 0.00077
#
#
nodes
1 x = 0 y = 0 z = 0 constraint = moving
2 x = 1 y = 0 z = 0
elements of type rod_2
1 nodes = [1,2] material = mat1 D = 1.1284
materials of type elastic
mat1 E = 210000000000 rho = 7850 nu = 0.3
constraints of type boundary_condition
moving vx = 1.0 ax = 0.0
trackers of type nodevelocity
1 node = [2] direction = X filename = Ver_07.trk target = [0.00043,0.000001,2.0,0.001]
controls
run from 0 to 0.002 step 0.000001
print every 0.0001 step
print tracker every 0.00001 step