An algorithm is presented for discrete element method simulations of energy‐conserving systems of frictionless, spherical particles in a reversed‐time frame. This algorithm is verified, within the limits of round‐off error, through implementation in the LAMMPS code. Mechanisms for energy dissipation such as interparticle friction, damping, rotational resistance, particle crushing, or bond breakage cannot be incorporated into this algorithm without causing time irreversibility. This theoretical development is applied to critical‐state soil mechanics as an exemplar. It is shown that the convergence of soil samples, which differ only in terms of their initial void ratio, to the same critical state requires the presence of shear forces and frictional dissipation within the soil system.

中文翻译：

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离散元方法的时间可逆性

提出了一种在逆时框架内对无摩擦球形颗粒节能系统的离散元方法仿真的算法。通过在LAMMPS代码中实现，在舍入误差的范围内验证了该算法。在不引起时间不可逆的情况下，无法将诸如粒子间摩擦，阻尼，旋转阻力，粒子破碎或键断裂等能量耗散机制纳入该算法。这种理论发展作为一个例子被应用于临界状态土壤力学。结果表明，仅在初始孔隙率方面不同的土壤样品收敛到相同的临界状态就需要在土壤系统内存在剪切力和摩擦耗散。