Characterization of a Vertical Submersible Six-stage Pump:
Accounting for the Induced Forces and Stresses
Patrick Zito Malonda
1
, Guyh Dituba Ngoma
1
, Walid Ghié
1
, Fouad Erchiqui
1
and Python Kabeya
2
1
University of Quebec in Abitibi-Témiscamingue, School of Engineering’s Department,
445, Boulevard de l’Université, Rouyn-Noranda, Quebec, J9X 5E4, Canada
2
University of Kinshasa, Department of Mechanical Engineering, Kinshasa, Democratic Republic of the Congo
Keywords: Vertical Submersible Multistage Pump, Axial and Radial Forces, Stress, Strain, CFX, Static Structural
Analysis.
Abstract: This study deals with the numerical investigation on the shaft behavior of a vertical submersible multistage
pump in terms of the axial and radial forces, and the stresses due to the liquid flow through the pump while
taking into account different conditions of operation, the gap between the impeller and the diffuser, the
rotating speed and the number of stages. This is to improve the pump performances while selecting the
bearings and/or the bushes of the submersible pumps in a suitable manner with a long operational life and
high reliability. From an existing vertical submersible six-stage pump, a pump model is developed. The
continuity, the Navier-Stokes, the stresses and the strains equations are applied to obtain by means of the
ANSYS-codes the fields of the liquid flow velocity and the pressure, the stresses, the strains, so as the axial
and radial forces. Numerical simulations are carried out to analyze the shaft behavior. The results obtained
for the pump head and the stress are validated using the experimental results of the pump head and the results
from the classical equations of stresses.
1 INTRODUCTION
The growth constantly of the number of deep mines
in construction and in exploitation in Canada leads
more and more to use very intense of the vertical
submersible multistage pumps with high pressure in
order to drain and to control the level of water in
mines. The considered vertical submersible six-
stage pump in this work is composed, inter alia, of a
vertical shaft, six impellers, six diffusers, a motor, a
suction body and a discharge body. The failing of a
pump in a mine can have a very ominous impact on
the environment. The security of the surrounding
work environment depends extensively on its
reliability, its good working and its life span. For the
constructors of the hydraulic pumps, the design, the
manufacture and the characterization of the vertical
submersible multistage pumps always present a big
challenge due to difficult to choose of the materials
of the pump components; the performances to reach
in terms of the pump head, the brake horsepower,
the axial and radial loads, the stresses and the
strains. A better manufacture of these pumps
requires a determination with precision of all key
parameters of its components while taking account,
in the design phase the axial and radial loads, the
strains and the stresses. Theoretical and
experimental several research works have been
achieved on the centrifugal pumps and the vertical
submersible multistage pumps in tie with the axial
and radial forces, the strains and the stresses on the
pump shaft (Karassik, 1998; Gülich, 2010; Karassik
et al., 2008; TM.P. S.p.A., 2003; Mohand-
Amokrane Abdelouahab et al., 2020; Bin, et al.,
2008; Zhou et al., 2014; Smith et al., 2005; Wang et
al., 2013; Wang et al., 2014; and Suke et al., 2015).
Indeed, in the books (Karassik, 1998; Gülich, 2010;
Karassik et al., 2008; and TM.P. S.p.A., 2003), the
authors presented theoretical and empiric
approaches to calculate, among others, the axial and
radial forces, the stresses and the strains on the
shafts of the centrifugal and submersible pumps. It
has been underlined that the developed relations are
dependent of the types of pump including the
measurements and the conditions of operations.
They cannot be automatically generalized to all
pumps. In the article (Mohand-Amokrane
Abdelouahab et al., 2020), the authors studied