Book excerpt: This book focuses on discrete element methods for arbitrarily shaped granular materials, including super-quadric models, spherical harmonic functions and level set methods, and numerical analysis of the flow characteristics of non-spherical granular materials. This book is used as a reference book for scientific researchers engaged in dynamic analysis of granular materials and optimal design of equipment structures in the fields of engineering mechanics, applied physics, mechanical engineering, and chemical engineering, as well as for graduate students or senior undergraduates of related majors in institutions of higher education.