# Undamped Single Degree of Freedom Oscillator
#
# References:
# 1. MSC/DYNA verification manual
#
# Problem Description
#
# A spring is fixed in one end and is connected to a mass at the other end.
# The mass has an inital velocity resulting in an oscillation.
# No damping is applied in this problem.
#
# Reference Results
#
# The analytical result for the deflection of the mass is as follows:
#
# x(t) = V(0) * sin(omega*t) / omega
# omega = sqrt( k / m)
# where k is the spring stiffness and m is the end mass
#
# Impact results correspond well with theory.
#
# Engineering data
#
# Length L = 1 m
# Stiffness k = 1 N / m
# End mass m = 1 kg
# Velocity Vi = 1 m / s
nodes
1 x = 0.0 y = 0.0 z = 0.0 constraint = fixed
2 x = 10.0 y = 0.0 z = 0.0 m = 1.0 constraint = moving
3 x = 5.0 y = 5.0 z = 0.0 constraint = fixed
elements of type BEAM_SPRING_2
1 nodes = [1,2,3] material = mat_1
materials of type SPRING
mat_1 kx = 1.0
constraints of type boundary_condition
fixed vx = 0 vy = 0 vz = 0 vrx = 0 vry = 0 vrz = 0 ax = 0 ay = 0 az = 0 arx = 0 ary = 0 arz = 0
moving ax = [0.0, 0.0, 0.0001, off, 100.0, off] vx = [0.0, 1.0, 0.0001, off, 100.0, off]
trackers of type nodedisplacement
1 node = [2] direction = x filename = Ver_09.trk target = [15.71, 0.00001, 0.0, 0.01]
controls
run from 0 to 17.0 step 0.001
print every 0.1 step
print tracker every 0.01 step