Investigation of the Potential Use of Hydrodiodes to Enhance the Volumetric Efficiency of a Centrifugal Pump

BACKGROUND: For centrifugal pumps, especially those with low specific speed coefficients, the volume efficiency is a very important parameter that largely determines the overall efficiency of the pump. This efficiency is influenced by the amount of leakage in the flow part of the pump, which in turn depends on the shape and size of the slot seals on the impeller. In this paper, we attempt to apply the well-known principle of operating a hydrodiode in order to reduce volume losses in the pump through a reduction in the flow coefficient of the slot seal, whose surface is profiled according to the principles of a hydrodiode. AIM: To confirm or deny, through hydrodynamic modeling techniques, the possibility of utilizing hydrodiode-like grooves on the surface of a slot seal in order to reduce the flow rate of liquid through the seal. METHODS: This paper utilizes a numerical modeling technique based on the solving of discrete analogs of the basic hydrodynamic equations. RESULTS: The parameters of liquid flow in slot seals with smooth surfaces, concentric grooves, and proposed profiled hydrodiodes in various sizes and shapes have been calculated. Flow coefficients for each type of seal have been determined, and comparative graphs have been constructed. CONCLUSION: Based on the findings of this study, it can be concluded that, overall, the use of hydrodiodes does not provide significant advantages over concentric groove designs, with significantly increased complexity in manufacturing.