how to get acceleration after Ansys harmonic analysis run 1

[hechengli]

after running the harmonic analysis in Ansys, the output is usually displacement against frequency, how can I get acceleration against frequency? Thanks

 

[GregLocock]

simple harmonic motion, ie velocity = j*w*x, acceleration is -w*w*x

w is the angular velocity, ie 2*pi*f. j is sqrt (-1). x is the displacement at a frequency. Cheers

Greg Locock

 

[nikolas]

look at the math operations icon in the time history postprocessor there u have options like add, subtract, multiply, derivate, integrate etc.
first describe the displacement by a variable and then follow the instructions given by Greg to get velocity and again to get the acceleration.
bye,
nikolas