how come simulation outcomes several times bigger than physical ones?

edited March 2017 in DualSPHysics_v4.0
Dear Alex,

Rcently i did a 2D wave tank physical experiment about subaerial block sliding along a ramp, then rushing to the still water to generate impulse waves.

Now i use dualsphysics4.0 to simulate the experiment depicted above, but this version4.0 we cannot
use DEM to simulate the friction between the block and the ramp. Because as you said this method is not appropriate for long-lasting frictional contacts. So i use the default sph method as you told me to simulate the interaction between the block and the ramp.

But the primary wave crest amplitude of numerical simulation outcome is several times bigger than physical ones ,what caused this big difference? what should i do to make the numerical simulation primary wave crest amplitude small enough to match the physical experiment results?

Regards

Comments

  • For this problem, you should apply a time history of velocity into the sliding block.
    See these:

    Ataie-Ashtiani, B, Mansour-Rezaei, S., “Modification of weakly Compressible Smoothed Particle Hydrodynamics for preservation of angular momentum in simulation of impulsive wave problems ” Coastal Engineering Journal, Vol. 51, No. 4, 363–386, 2009

    Ataie-Ashtiani, B., G. Shobeiry, Numerical simulation of landslide impulsive waves by Modified Smooth Particle Hydrodynamics, International Journal for Numerical Methods in Fluids, Volume 56, Issue 2 , Pages 209–232, January 2008

  • the slide movement process should happen automatically ,we should not fix it
  • Dear moh,

    what we treat the sliding block as? a floating object? and if we treat it like that, then we cannot prescribe its movement along with time in dualsphysics4.0. The articles you referred to may use sphysics written in Fortran to simulate the block slide. and treat the block as discretised sph particles.

    Regards
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