Abstract: Background: Vortex diode is a kind of uniflow component, and a simple vortex diode contains a vortex chamber, a tangential nozzle and an axial nozzle. Purpose: The aim is to investigate the effect of chamfered vortex chamber structure on vortex diode performance. Methods: Computational Fluid Dynamics (CFD) simulations were used on vortex diodes with four different chamfered structures. Standard k-ε model was selected for forward flow, while RNG (Renormalization Group) k-ε model was selected for reverse flow. Results: The results show that compared with standard structure, all the other three chamfered structures can reduce the positive flow resistances at relatively high Reynolds number, while the reverse flow resistances are also reduced. Among them, the chamfered structure of 3/4 vortex chamber height, can reduce the forward flow resistance to the greatest extent while keeping minimum impact on the reverse flow resistance. Conclusion: The chamfered structure of 3/4 vortex chamber height improves the overall performance of a vortex diode most significantly. The results of the simulation can provide some basis for optimizing the vortex diode performance.

Key words: Vortex diode, Vortex chamber, Chamfered, Resistance coefficient