Abstract
Capability for handling entrained gas is an important design consideration for centrifugal pumps used in petroleum, chemistry, nuclear applications. An experimental evaluation on their two phase performance is presented for two centrifugal pumps working under air-water mixture fluid conditions. The geometries of the two pumps are designed for the same flow rate and shut off head coefficient with the same impeller rotational speed. Overal pump performance and unsteady pressure pulsation information are obtained at different rotational speeds combined with various inlet air void fractions (α0) up to pump stop condition. As seen from the test results, pump 2 is able to deliver up to 10% two-phase mixtures before pump shut-off, whereas pump 1 is limited to 8%. In order to understand the physics of this flow phenomenon, a full three-dimensional unsteady Reynolds Average Navier-Stokes (3D-URANS) calculation using the Euler–Euler inhomogeneous method are carried out to study the two phase flow characteristics of the model pump after corresponding experimental verification. The internal flow characteristics inside the impeller and volute are physically described using the obtained air distribution, velocity streamline, vortex pattern and pressure pulsation results under different flow rates and inlet void fractions. Pump performances would deteriorate during pumping two-phase mixture fluid compared with single flow conditions due to the phase separating effect. Some physical explanation about performance improvements on handing maximum acceptable inlet two phase void fractions capability of centrifugal pumps are given.
Highlights
Centrifugal pumps are important energy conversion devices, widely used in industrial petroleum, nuclear power and chemical engineering processes [1]
A semi-empirical approach for pumping maximum attainable inlet air void fraction values has been recently proposed based on the importance of both impeller rotational speed and inlet relative velocity effects [2]
Some numerical studies based on the computational fluid dynamics (CFD) approach of features such as bubble size, drag force, and gas-liquid interphase momentum transfer have been performed in order to obtain suitable two-phase flow models [24]
Summary
Centrifugal pumps are important energy conversion devices, widely used in industrial petroleum, nuclear power and chemical engineering processes [1]. It is especially important to thoroughly study and reveal the internal flow characteristic of centrifugal pumps under gas entrainment conditions. Si et al [15,16] experimentally studied the overall performance and pressure pulsation characteristics of a centrifugal pumps under inlet air-water two phase flow conditions. Some numerical studies based on the CFD approach of features such as bubble size, drag force, and gas-liquid interphase momentum transfer have been performed in order to obtain suitable two-phase flow models [24]. Reviewed experimental and numerical studies of Electrical Submersible Pumps (ESPs) under gas-liquid flow conditions, and explained the bubbly diameter variation is the main reason for the gas phase distribution inside the impeller under different rotational speeds. Set-up and Methodthe two-phase inner flow characteristics after experimental verification
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
