# Mass Impacting Rod using Rod_2 elements
#
# References
# 1. S. Timoshenko and J. N. Goodier, "Theory or Elasticity", 2nd ed.,
# McGraw-Hill, New York, 1951, pp. 497-504
# 2. "MSC/MASTRAN Verification Problem Manual (Version 65)", MSR-63,
# MacNeal-Schwendler. May 1988
# 3. MSC/DYNA verification manual
#
# Problem Description
# An elastic rod is fixed in one end and then struck in the other end by
# a moving mass.
# The mass is rigid and has an initial velocity of V0. The free end of the
# rod has the same initial velocity which is at the instant of impact.
# The relative motion of the mass and the rod end is the parameters of
# interest here.
#
# Model Description
# The rod is modeled using 20 ROD_2 elements and a free node representing
# the impacted mass.
# The contact is handled by Impact as default, extending from the free end
# by a radius, the same as the rod cross section radius.
# The timestep is reduced and fixed to prevent numerical instabilities.
#
# Two trackers are used to print the nodal displacements into files for viewing.
# Use any plot program to read them or the File->Import->Graph in GID.
#
# Engineering Data
#
# Rod Length: L = 100.0 m
# Cross sectional area: A = 1 m2 => R = 0.564 m
# Young's modulus: E = 1000 N/m2
# Poissons Ratio: nu = 0.3
# Mass density: rho = 0.1 kg/m3
# Rod mass: m = rho*A*L = 10.0 kg
#
# Results
# For results, see the references.
# In words, the rod end and impact mass should follow each other to
# a maximum deflection of -0.0865 at time 2.1.
# Separation then starts at time 3.3 with a second hit at 4.3
#
nodes
1 x = 0 y = 0 z = 0 constraint = fixed
2 x = 5 y = 0 z = 0 constraint = line
3 x = 10 y = 0 z = 0 constraint = line
4 x = 15 y = 0 z = 0 constraint = line
5 x = 20 y = 0 z = 0 constraint = line
6 x = 25 y = 0 z = 0 constraint = line
7 x = 30 y = 0 z = 0 constraint = line
8 x = 35 y = 0 z = 0 constraint = line
9 x = 40 y = 0 z = 0 constraint = line
10 x = 45 y = 0 z = 0 constraint = line
11 x = 50 y = 0 z = 0 constraint = line
12 x = 55 y = 0 z = 0 constraint = line
13 x = 60 y = 0 z = 0 constraint = line
14 x = 65 y = 0 z = 0 constraint = line
15 x = 70 y = 0 z = 0 constraint = line
16 x = 75 y = 0 z = 0 constraint = line
17 x = 80 y = 0 z = 0 constraint = line
18 x = 85 y = 0 z = 0 constraint = line
19 x = 90 y = 0 z = 0 constraint = line
20 x = 95 y = 0 z = 0 constraint = line
21 x = 100 y = 0 z = 0 constraint = line
22 x = 100.565 y = 0 z = 0 constraint = hit m = 10.0
elements of type rod_2
1 nodes = [1,2] D = 1.128 material = mat_1 factor = 10000
2 nodes = [2,3] D = 1.128 material = mat_1 factor = 10000
3 nodes = [3,4] D = 1.128 material = mat_1 factor = 10000
4 nodes = [4,5] D = 1.128 material = mat_1 factor = 10000
5 nodes = [5,6] D = 1.128 material = mat_1 factor = 10000
6 nodes = [6,7] D = 1.128 material = mat_1 factor = 10000
7 nodes = [7,8] D = 1.128 material = mat_1 factor = 10000
8 nodes = [8,9] D = 1.128 material = mat_1 factor = 10000
9 nodes = [9,10] D = 1.128 material = mat_1 factor = 10000
10 nodes = [10,11] D = 1.128 material = mat_1 factor = 10000
11 nodes = [11,12] D = 1.128 material = mat_1 factor = 10000
12 nodes = [12,13] D = 1.128 material = mat_1 factor = 10000
13 nodes = [13,14] D = 1.128 material = mat_1 factor = 10000
14 nodes = [14,15] D = 1.128 material = mat_1 factor = 10000
15 nodes = [15,16] D = 1.128 material = mat_1 factor = 10000
16 nodes = [16,17] D = 1.128 material = mat_1 factor = 10000
17 nodes = [17,18] D = 1.128 material = mat_1 factor = 10000
18 nodes = [18,19] D = 1.128 material = mat_1 factor = 10000
19 nodes = [19,20] D = 1.128 material = mat_1 factor = 10000
20 nodes = [20,21] D = 1.128 material = mat_1 factor = 10000
materials of type elastic
mat_1 E = 1000 nu = 0.3 rho = 0.1
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
line vy = 0 vz = 0 ay = 0 az = 0
hit vx = [0,-0.1,0.00001,off,10,off] vy = 0 vz = 0 ax = [0,0,0.00001,off,10,off] ay = 0 az = 0
trackers of type nodedisplacement
1 node = [21] direction = x filename = Ver_03_end.trk target = [2.10,0.001,-0.0865,0.0001]
2 node = [22] direction = x filename = Ver_03_mass.trk
controls
run from 0 to 5.0 step 0.0005
print every 0.1 step
print tracker every 0.01 step