# Wave propagation in a bar
#
# References
# 1. Concepts and Applications of Finite Element Analysis
# Robert D. Cook et al. Third Edition, ISBN 0-471-84788-7
#
# Problem Description
# An undamped uniform steel bar is loaded in the tip with a load
# that is held constant from the start.
# The bar is initially at rest and is modelled by 40 rod elements
# of equal length. The bar is only allowed to move in one direction
# making this a one dimensional problem.
#
# The stress / time history of element 20 midpoint is read with a
# tracker.
#
#
# Engineering Data
#
# Rod Length: L = 20.0 in
# Cross sectional area: A = 1.0 in2 => D = 1.128 in
# Young's modulus: E = 30 (E6) psi
# Poissons Ratio: nu = 0.3
# Mass density: rho = 7.4E-4 lb-sec2/in4
#
# Load: P0 = 100 lb applied at t=0 and constant
#
# Results
# For exact results, see the book references.
# The following description is taken from a graph in the book.
#
# In words, the stresses in rod 20 should remain = 0 until time
# 5.0E-5 sec when a pressure of 100 psi (-100) should occur as an average level.
#
# This level remains until reflection of wave occurs at 1.5E-4 sec and
# the pressure increases to 200 psi (-200).
#
# The tracker reflects this in Impact as a load (lb) in the rod.
# With an area of 1 in2, this corresponds to -100 / -200 lb respectively.
#
nodes
1 x = 0.0 y = 0 z = 0 constraint = line load = hit
2 x = 0.5 y = 0 z = 0 constraint = line
3 x = 1.0 y = 0 z = 0 constraint = line
4 x = 1.5 y = 0 z = 0 constraint = line
5 x = 2.0 y = 0 z = 0 constraint = line
6 x = 2.5 y = 0 z = 0 constraint = line
7 x = 3.0 y = 0 z = 0 constraint = line
8 x = 3.5 y = 0 z = 0 constraint = line
9 x = 4.0 y = 0 z = 0 constraint = line
10 x = 4.5 y = 0 z = 0 constraint = line
11 x = 5.0 y = 0 z = 0 constraint = line
12 x = 5.5 y = 0 z = 0 constraint = line
13 x = 6.0 y = 0 z = 0 constraint = line
14 x = 6.5 y = 0 z = 0 constraint = line
15 x = 7.0 y = 0 z = 0 constraint = line
16 x = 7.5 y = 0 z = 0 constraint = line
17 x = 8.0 y = 0 z = 0 constraint = line
18 x = 8.5 y = 0 z = 0 constraint = line
19 x = 9.0 y = 0 z = 0 constraint = line
20 x = 9.5 y = 0 z = 0 constraint = line
21 x = 10.0 y = 0 z = 0 constraint = line
22 x = 10.5 y = 0 z = 0 constraint = line
23 x = 11.0 y = 0 z = 0 constraint = line
24 x = 11.5 y = 0 z = 0 constraint = line
25 x = 12.0 y = 0 z = 0 constraint = line
26 x = 12.5 y = 0 z = 0 constraint = line
27 x = 13.0 y = 0 z = 0 constraint = line
28 x = 13.5 y = 0 z = 0 constraint = line
29 x = 14.0 y = 0 z = 0 constraint = line
30 x = 14.5 y = 0 z = 0 constraint = line
31 x = 15.0 y = 0 z = 0 constraint = line
32 x = 15.5 y = 0 z = 0 constraint = line
33 x = 16.0 y = 0 z = 0 constraint = line
34 x = 16.5 y = 0 z = 0 constraint = line
35 x = 17.0 y = 0 z = 0 constraint = line
36 x = 17.5 y = 0 z = 0 constraint = line
37 x = 18.0 y = 0 z = 0 constraint = line
38 x = 18.5 y = 0 z = 0 constraint = line
39 x = 19.0 y = 0 z = 0 constraint = line
40 x = 19.5 y = 0 z = 0 constraint = line
41 x = 20.0 y = 0 z = 0 constraint = fixed
elements of type rod_2
1 nodes = [1,2] D = 1.128 material = mat_1
2 nodes = [2,3] D = 1.128 material = mat_1
3 nodes = [3,4] D = 1.128 material = mat_1
4 nodes = [4,5] D = 1.128 material = mat_1
5 nodes = [5,6] D = 1.128 material = mat_1
6 nodes = [6,7] D = 1.128 material = mat_1
7 nodes = [7,8] D = 1.128 material = mat_1
8 nodes = [8,9] D = 1.128 material = mat_1
9 nodes = [9,10] D = 1.128 material = mat_1
10 nodes = [10,11] D = 1.128 material = mat_1
11 nodes = [11,12] D = 1.128 material = mat_1
12 nodes = [12,13] D = 1.128 material = mat_1
13 nodes = [13,14] D = 1.128 material = mat_1
14 nodes = [14,15] D = 1.128 material = mat_1
15 nodes = [15,16] D = 1.128 material = mat_1
16 nodes = [16,17] D = 1.128 material = mat_1
17 nodes = [17,18] D = 1.128 material = mat_1
18 nodes = [18,19] D = 1.128 material = mat_1
19 nodes = [19,20] D = 1.128 material = mat_1
20 nodes = [20,21] D = 1.128 material = mat_1
21 nodes = [21,22] D = 1.128 material = mat_1
22 nodes = [22,23] D = 1.128 material = mat_1
23 nodes = [23,24] D = 1.128 material = mat_1
24 nodes = [24,25] D = 1.128 material = mat_1
25 nodes = [25,26] D = 1.128 material = mat_1
26 nodes = [26,27] D = 1.128 material = mat_1
27 nodes = [27,28] D = 1.128 material = mat_1
28 nodes = [28,29] D = 1.128 material = mat_1
29 nodes = [29,30] D = 1.128 material = mat_1
30 nodes = [30,31] D = 1.128 material = mat_1
31 nodes = [31,32] D = 1.128 material = mat_1
32 nodes = [32,33] D = 1.128 material = mat_1
33 nodes = [33,34] D = 1.128 material = mat_1
34 nodes = [34,35] D = 1.128 material = mat_1
35 nodes = [35,36] D = 1.128 material = mat_1
36 nodes = [36,37] D = 1.128 material = mat_1
37 nodes = [37,38] D = 1.128 material = mat_1
38 nodes = [38,39] D = 1.128 material = mat_1
39 nodes = [39,40] D = 1.128 material = mat_1
40 nodes = [40,41] D = 1.128 material = mat_1
materials of type elastic
mat_1 E = 30E6 nu = 0.3 rho = 7.4E-4
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
trackers of type rodforce
1 element = [20] filename = Ver_13.trk
loads
hit fx = 100
controls
run from 0 to 0.2E-3 step 0.2E-6
print every 1.0E-6 step
print tracker every 1.0e-6 step