Experimental and Numerical Investigation of Centrifugal Vortex Pump Operating Benefits for Energy Efficient Systems

Abstract

One of the ways to improve the performance of centrifugal pumps, proposed and experimentally validated by our research, is the method of creating so-called coherent structures, vortices and turbulence in the peripheral area of the centrifugal stage by adding a vortex rim to the back side of centrifugal rotor. A new construction of the pump, so called centrifugal vortex pump (CV), combines the good sides of these two types of pumps: high head of the vortex pump and high efficiency of the centrifugal pump. In addition, centrifugal pumps deliver higher flow rates with lower pressures, vortex pumps deliver higher pressures but with lower flow rates. For centrifugal vortex pumps, the vortex blades are located at the rear of the centrifugal rotor. The outer diameter of the vortex rim (VR) is smaller than the outer diameter of the centrifugal rotor (CR). The vortex rim induces vorticity to a portion of the flow that has passed through the centrifugal rotor. This vortexed flow is then reunited with the rest of the flow that has not been pulled down by vortex rotor. The vortex energy of that additional stream transfers some of its kinetic energy to the main stream. This added kinetic energy is converted to a pressure that accumulates the pressure exerted by the centrifugal rotor, and thus the vortex rim improves the overall pump performance. An intense process of gas dispersion occurs in the vortex region, which increases the stability of the pump when pumping a mixture of liquids and gases. The process of energy conversion in a centrifugal vortex pump, i.e., flow visualisation of mixing streams from a centrifugal rotor and a vortex rotor, and the quantization and superpositions have been shown in this paper.

Influence of Axial Matching between Inducer and Impeller on Energy Loss in High-Speed Centrifugal Pump

“…Zhang et al [4] analyzed the hydraulic performance and dynamic characteristics of the centrifugal pump and indicated the pump has better hydraulic behavior when the volute tongue is right in the middle of the two vanes. Mihalic et al [5] improved the performance of a centrifugal pump by adding a vortex rim on the back of the centrifugal rotor, and increased the stability of the pump when pumping a liquid and gas mixture. Shigemitsu et al [6] found that when the centrifugal pump has splitter blades, the flow condition at the rotor outlet becomes uniform, the recirculation zone is suppressed, the volute efficiency is improved, and the vortex loss is reduced.…”