Although flow in biological materials sometimes behaves like a continuous one, it cannot be simulated with continuity-based modeling when it comes to discontinuous flow behavior. The Discrete Element Method (DEM) in combination with Computational Fluid Dynamics (CFD) is a computational method for modeling particles in fluid flow by tracking their motion. DEM is widely used in the field of engineering, and its use in the agricultural field is increasing. This study analyzes the CFD-DEM relationship of biological material in aerodynamic systems and reviews current applications. In the article, the definition of aerodynamic systems as a basic principle, particle-fluid and particle-particle interaction forces in the system, modeling of particle motions, CFD-DEM coupling method, and analysis applications of agricultural aerodynamic systems are examined. In this study, simulation experiments were carried out at 100 g/s and 200 g/s straw feeding values at each value of 18-15-12-10-8-6-4 m/s air and straw inlet velocities. The flow near the cyclone walls caused the straw particles to be directed towards the lower exit end of the cyclone. At feed densities of 100 g/s and 200 g/s, the least particle output was obtained at a rate of 18 m/s. The highest cyclone output efficiency was obtained at feed densities of 100 g/s and 200 g/s at a velocity of 12 m/s. The compatibility of the trial simulation results with the literature showed that the CFD-DEM application is an important approach to study the behavior of particulate matter in fluids.