Analysis of dynamic discharge pressures in cylindrical slender silos with a flat bottom or with a hopper: comparison with Eurocode 1

Few models simulate the discharge of flat-bottom silos by using finite elements. This paper presents a new dynamic model for silo discharge using the Drucker–Prager plasticity model. The model was used to study discharge in mixed flow and mass flow silos with rigid walls. Various silos were analysed, and pressures under different flow patterns were compared. Results were also compared with Eurocode 1—part 4 on actions in silos and tanks, which is the standard used in the European Union. Overpressure coefficients due to discharge were obtained in all cases. In the case of flat-bottom silos, overpressures occurred in the lower part of the silo. The values obtained for overpressures were lower than the values obtained in the case of mass flow hopper silos. The effects of wall friction and outlet radius were also analysed.

[1]  J. C. Simo,et al.  An augmented lagrangian treatment of contact problems involving friction , 1992 .

[2]  Robert Charlier,et al.  FRICTIONAL CONTACT FINITE-ELEMENTS BASED ON MIXED VARIATIONAL-PRINCIPLES , 1993 .

[3]  Icíar Alfaro,et al.  Simulation of axisymmetric discharging in metallic silos. Analysis of the induced pressure distribution and comparison with different standards , 2002 .

[4]  Thorsten W. R. Keiter,et al.  Numerical Aspects of FE Simulations of Granular Flow in Silos , 2001 .

[5]  Serge Cescotto,et al.  Large strain dynamic analysis using solid and contact finite elements based on a mixed formulation; application to metal forming , 1994 .

[6]  Jan C. Jofriet,et al.  A numerical model for flow of granular materials in silos. Part 3 : Parametric study , 1997 .

[7]  T. F. Fwa,et al.  Friction Model for Finite Element Analyses of Silos , 1977 .

[8]  J. M. Rotter,et al.  Guide for the Economic Design of Circular Metal Silos , 2001 .

[9]  A. Couto,et al.  Discharge and the Eccentricity of the Hopper Influence on the Silo Wall Pressures , 2001 .

[10]  P. Aguado,et al.  SE—Structures and Environment: Static and Dynamic Silo Loads using Finite Element Models , 2001 .

[11]  D. M. Walker.  An approximate theory for pressures and arching in hoppers , 1966 .

[12]  Jin Y. Ooi,et al.  Computations of granular flow and pressures in a flat bottomed silo , 2001 .

[13]  Qinggang Meng,et al.  Finite element analysis of bulk solids flow : Part 1, development of a model based on a secant constitutive relationship , 1997 .

[14]  P. Aguado,et al.  Mechanical properties of granular agricultural materials , 2002 .

[15]  Jan C. Jofriet,et al.  A Numerical Model for Flow of Granular Materials in Silos. Part 1: Model Development , 1997 .

[16]  A. Couto,et al.  Numerical Simulation of Wall Pressure during Discharge of Granular Material from Cylindrical Silos with Eccentric Hoppers , 2003 .

[17]  D. C. Drucker,et al.  Soil mechanics and plastic analysis or limit design , 1952 .

[18]  J. M. Rotter,et al.  The sensitivity of silo flow and wall stresses to filling method , 2001 .

[19]  Gisle G. Enstad,et al.  Numerical Calculations of Wall Pressures and Stresses in Steel Cylindrical Silos with Concentric and Eccentric Hoppers , 2003 .

[20]  Jørgen Nielsen,et al.  Pressures from flowing granular solids in silos , 1998, Philosophical Transactions of the Royal Society of London. Series A: Mathematical, Physical and Engineering Sciences.

[21]  J. M. Rotter,et al.  Verification of a 3-dimensional model for filling pressures in square thin-walled silos , 2003 .

[22]  Alaa E. Elwi,et al.  Incipient Flow in Silo‐Hopper Configurations , 1990 .

[23]  Christopher J. Brown,et al.  The influence of the base boundary condition in modelling filling of a metal silo , 2004 .

[24]  Dominique Guines,et al.  3D Finite-Element Simulation of a Square Silo with Flexible Walls , 2001 .

[25]  M. A. Diez,et al.  Viscoplastic incompressible flow of frictional-cohesive solids , 1992 .