Bench tests methodological specifics of submersible electric centrifugal pumps gas separating installations for oil extraction

The article analyzes the flow gas-liquid mixture features inthe flow part of the impellers of multiphase stages pumping gas-liquid mixtures. By analogy with the coefficient specific speed of a pump for a single-phase liquid and the cavitation specific speed, a specific speed for multiphase pump stages is proposed. It is shown that the operation of blade pumps on multiphase media depends on the characteristics of the flow of the working fluid in all parts of the flow path, including the conditions at the inlet to the impeller, the flow in the blade cascade of the impeller, the guide vane, the outlet elements of the pump. Design changes in traditional blade cascades are recommended, and a new type is proposed: a multi-row cascade system.

Features of improving the design of bladed impellers for operation on gas-liquid mixtures

Trulev¹,

Timushev

Lomakin

2022

Design Features of Impeller Vane Cascades to Pump Gas and Liquid Mixtures Conducive to Reducing Gas Cavern Magnitudes

Trulev¹,

Lomakin

Klindukh

et al. 2022

We employed numerical simulation methods to investigate how design features of impeller vane cascades in a centrifugal pump processing gas and liquid mixtures will affect the magnitude of gas caverns. We derived a mathematical model for multiphase flow of incompressible fluid. We performed hydrodynamic computations for various impeller vane cascade designs. We identified regions of local gas separation in commercially available and improved cascades that may result in gas plug formation and pump failure. The paper investigates the effect of the following parameters on the magnitude of a gas cavern: the angle of attack, pressure feed, pressure gradient, and the presence of through holes and transverse cutouts in a single-tier vane cascade. We consider design features of stacked van cascades and investigate how the vane length and vane distribution uniformity in the blading section of a stacked vane system affect gas cavern magnitudes. We selected the optimum vane cascade design for multiphase impellers. The paper then indicates further lines of research.

Improvement of the gas separator flow path using the multiphase coefficient of the discrete particles relative motion speed

Trulev,

Timushev,

Lomakin

et al. 2023

The paper analyzes features of the flowing formation fluid that contains free gas bubbles in the flow part of a vortex-type separator with the movable screw. Expressions are derived for a dimensionless multiphase coefficient of the discrete particles relative separation rate and the multiphase similarity criterion, which are making it possible to evaluate the gas separator efficiency, design and develop new devices based on the previously created highly efficient models. The derived equations allow determining the main geometric dimensions of the gas separator flow part based on the given radial dimensions, nominal flow rate and permissible content of free gas at the inlet. For the obtained geometric dimensions of the gas separator flow part, it becomes possible to construct dependences of the separation coefficient and the permissible amount of free gas at the inlet on the rotor rotation speed, flow rate and physical properties of the multiphase mixture.