ABSTRACT: Important developments have been made in computational simulations of discontinua in recent years including DDA, DEM, FDEM, MD. Fracture, fragmentation, shape, deformability and many other issues have been addressed to such an extent that the field of applications has grown exponentially and has now included applications ranging from astrophysics to nano-science, and from medical engineering to mineral processing and material sciences. As a result a young new discipline called the Computational Mechanics of Discontinua has been created. One of the challenging problems is incorporation of CFD techniques into methods of the Computational mechanics of Discontinua. In this work a successful coupling of FDEM and fluid mechanics solvers based on immersed boundary method and large eddy simulation has been accomplished and demonstrated using a diverse field of applications.