Page 160 - Thomson, William Tyrrell-Theory of Vibration with Applications-Taylor _ Francis (2010)
P. 160
Sec. 5.5 Digital Computation 147
substantially. They are Tj = 0.3803 and t2 = 0.1462 s. We therefore arbitrarily
choose a value of Ai = 0.01 s which is smaller than T2/IO.
To start the computation, note that the initial accelerations are Xj = 0 and
y'l = 160, so that the starting equation, Eq. (4.7-8), can be used only
for y.
>'2 = 5^1
For the calculation of X2, the special starting equation, Eq. (4.7-10), must be used
together with the differential equations
j;2 = ¡X2Ai^
X2 = —720x2 + 360y2
Eliminating X2 gives the following equation for X2:
60y2
1 + 120 Ai 2
The flow diagram for the computation is shown in Fig. 5.5-2. The Fortran
program with the computed results follows and the plot is presented in Fig. 5.5-3.
Figure 5.5-2. Flow diagram for computation.
