Numerical analysis of cyclone separator with different structural parameters for rapeseed combine harvester based on CFD

Existing development for cyclone separation cleaning components of the rapeseed combine harvester, which employs the suspending airflow to separate the rapeseeds from the materials other than grain (MOG), has the challenge to figure out the optimal structural parameters of the cyclone separator, highlighting a need for exploration of the invisible airflow based on Computational Fluid Dynamics (CFD). The cyclone separator, a crucial component of the cleaning device, is consisted of the upper cone, the cylinder part, and the lower cone. Taking the distribution of high-velocity area and low-velocity area of the airflow field inside the cyclone separator as the object, the simulation model of the cyclone separator with different structural parameters was built, and a single-factor simulation experiment was carried out by using Fluent software. The results indicated that the distribution of the airflow field was more axisymmetric when the diameter of cylinder part, the diameter of rapeseeds outlet, the angle of the upper cone, the angle of lower cone, and the height of cylinder part were 350 mm, 200 mm, 30 °, 75 °, and 240 mm, respectively. Under the combination of structural parameters above, the validation was conducted by applying the multifunctional test bench for the rapeseed combine harvester. It was found that the relative error of the simulation model was 1.27%. Furthermore, the cleaning ratio and the loss ratio of the cyclone separation cleaning device were tested as 91.47% and 5.08%, respectively. The research provides a method for the improvement of cleaning devices for rapeseed harvesting.