*HEADING 1D transient wave propagation, acoustic medium, incident wave load, spherical and defined through pressure amplitude ** ** C = root (K/rho)= 343.05 m/s K=bulk mod, rho=density. ** ** Analytical solution to prescribed constant acceleration of a0 at x=0 ** ** p(x,t) = (K a0 / c^2) (ct - x) for x < ct ** = 0 for x > ct ** *PREPRINT,ECHO=NO,HISTORY=NO,MODEL=YES *NODE, NSET=ODB_NSET 1, 0, 101, 1, 501, 0,.5E-2 601, 1,.5E-2 1001, 0, 1.E-2 1101, 1, 1.E-2 *NGEN,NSET=CHANNEL 1,101 1001,1101 *NSET,NSET=SAMPLE,GENERATE 1,101 *ELEMENT,TYPE=AC2D3 1,1,2,1002 2,1002,1001,1 *ELGEN,ELSET=CHANNEL 1,100,1,2 2,100,1,2 *NSET,NSET=QA_TEST,GENERATE 1,11 ************************** *SURFACE,NAME=IW_LOAD 2,S2 ************************** ** CROSS-SECTION IS 1.0E-4 *SOLID SECTION,MATERIAL=AIR,ELSET=CHANNEL 1.E-2, ** *MATERIAL,NAME=AIR *DENSITY 1.21, *ACOUSTIC MEDIUM,BULK MODULUS 0.1424E6, ** ************************** *INCIDENT WAVE PROPERTY,NAME=IWPROP,TYPE=SPHERE 0.0,0.0, -10.0E04,0.0, *INCIDENT WAVE FLUID PROPERTY 0.1424E6,1.21,0.0 *AMPLITUDE,DEFINITION=TABULAR,NAME=PRESSUREVTIME 0.0,0.0,1.0,-1.0 ************************** *RESTART,WRITE,FREQUENCY=10000 ** *STEP,INC=1000 *DYNAMIC .0001,.0044 ** DEFINE NONREFLECTIVE BOUNDARY AT X=1 *IMPEDANCE 199,I2 ** *INCIDENT WAVE,PRESSUREAMPLITUDE=PRESSUREVTIME,PROPERTY=IWPROP IW_LOAD,415.09517 ** *OUTPUT,FIELD, FREQUENCY=200 *NODE OUTPUT POR, *OUTPUT,HISTORY,OP=ADD,FREQUENCY=20 *NODE OUTPUT,NSET=qa_test POR, *ENDSTEP