The perplexing puzzle posed by a pile of apples

Watson, Andrew
December 1991
New Scientist;12/14/91, Vol. 132 Issue 1799, p19
Discusses Kurt Liffman and his colleagues' development of a computer model for a particulate pile, which mathematicians call a sand pile. Background of Liffman's computer model; Shear forces predicted by the model; Project to explore the force patterns between particles in suspension.


Related Articles

  • Numerical predictions of noise due to subsonic jets from nozzles with and without chevrons.  // Noise & Vibration Worldwide;Jul2010, Vol. 41 Issue 7, p35 

    The article presents a study on the use of Shear Stress Transport model to measure numerical simulations of compressible, turbulent and round jets in 2010.

  • Dynamic evolutions of multiple toroidal Alfvén eigenmodes with energetic particles. Zhu, J.; Ma, Z. W.; Fu, G. Y. // Physics of Plasmas;Dec2013, Vol. 20 Issue 12, p122508 

    Kinetic simulations based on a reduced model are carried out to study dynamic evolutions of multiple toroidicity-induced shear Alfvén eigenmodes driven by energetic particles. It is found that passing and trapped particles play quite different roles on the mode evolution. For cases without...

  • Alignment of particles in sheared viscoelastic fluids. Santos de Oliveira, I. S.; van den Noort, A.; Padding, J. T.; den Otter, W. K.; Briels, W. J. // Journal of Chemical Physics;9/14/2011, Vol. 135 Issue 10, p104902 

    We investigate the shear-induced structure formation of colloidal particles dissolved in non-Newtonian fluids by means of computer simulations. The two investigated visco-elastic fluids are a semi-dilute polymer solution and a worm-like micellar solution. Both shear-thinning fluids contain long...

  • Numerical simulation of rip-raps with the distinct element method. Mittelbach, Livia // AIP Conference Proceedings;Jun2013, Vol. 1542 Issue 1, p1178 

    and costal shores. They have to resist hydraulic loads such as ship and wind induced waves, tidal and ship induced currents, tidal varying water levels and storm surges. The numerical modelling of rip-rap revetments is undertaken by using the Distinct Element Method in three dimensions. With the...

  • Sensitivity analyses in snow avalanche dynamics modeling and implications when modeling extreme events. Borstad, Christopher P.; McClung, D. M. // Canadian Geotechnical Journal;Sep2009, Vol. 46 Issue 9, p1024 

    We present the first snow avalanche dynamics model simulations to start in the middle of the avalanche path at the maximum expected speed for an extreme event. We first present a sensitivity analysis of the dynamics model to the various model inputs. A single-parameter Coulomb-type friction...

  • An Investigation on Temperature Distribution Within the Substrate and Nozzle Wall in Cold Spraying by Numerical and Experimental Methods. Li, Wen-Ya; Yin, Shuo; Guo, Xueping; Liao, Hanlin; Wang, Xiao-Fang; Coddet, Christian // Journal of Thermal Spray Technology;Jan2012, Vol. 21 Issue 1, p41 

    During cold spraying (CS), heat exchange between the hot driving gas and the solid bodies, e.g., spray nozzle and substrate, results in the temperature redistribution within the solid bodies. In this study, numerical and experimental investigations on the heating behavior of the substrate and...

  • Numerical simulation of shear layer instability using a scheme with ninth-order multioperator approximations. Lipavskii, M.; Tolstykh, A.; Chigirev, E. // Computational Mathematics & Mathematical Physics;Mar2013, Vol. 53 Issue 3, p296 

    For equations with convective terms, a difference scheme is described based on ninth-order multioperator approximations. Its optimization aimed at achieving a high resolution of small scales of solutions is discussed. The scheme is applied to test problems, and shear layer instability is...

  • Turbulence in a Sheared, Salt-Fingering-Favorable Environment: Anisotropy and Effective Diffusivities. Kimura, Satoshi; Smyth, William; Kunze, Eric // Journal of Physical Oceanography;Jun2011, Vol. 41 Issue 6, p1144 

    Direct numerical simulations (DNS) of a shear layer with salt-fingering-favorable stratification have been performed for different Richardson numbers Ri and density ratios Rρρ. In the absence of shear (Ri == ∞∞), the primary instability is square planform salt fingering,...

  • Natural frequencies of functionally graded beams by the various shear deformation theories. Jiang Wu; Song Xiang // Applied Mechanics & Materials;2014, Issue 680-681, p216 

    Various higher order shear deformation theories of Levinson, Touratier, Karama are utilized to calculate the natural frequencies of functionally graded beams. The governing differential equations are solved by an analytical method. The present results are compared with the results of Aydogdu...


Read the Article


Sorry, but this item is not currently available from your library.

Try another library?
Sign out of this library

Other Topics