Study of the Effects of Blockage and Impeller Fault in Centrifugal Pump using CFD Simulation
Date
2023-11
Authors
Journal Title
Journal ISSN
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Publisher
IOE Pulchowk Campus
Abstract
Centrifugal pumps have been used as a vital component in most of the industrial
applications aiding the way for liquid transport in various sectors ranging from the
construction, manufacturing, hydropower, wastewater treatments to petrochemicals.
The efficient and reliable operation of these pumps is very much crucial for any
industry. However, the pumps are prone to various faults and defects during their life
cycle which arises the necessity for addressing certain diagnostic tools for early fault
detections and preventions. For these pumps to operate efficiently, it is very much
important to understand the intricate dynamics inside the pump. This paper
investigates the use of the open-source software OpenFOAM as one of the tools used
in Computational Fluid Dynamics for studying the flow field inside the centrifugal
pump.
Steady-state simulations are performed using the simpleFoam solver via the MRF
approach while the unsteady transient simulations are performed using pimpleFoam
solver via the Sliding Mesh approach. A CFD model of Oberdorfer 60P pump have
been developed to simulate the fluid flow pattern inside the centrifugal pump. The
study mainly focuses on assessing critical pump parameters such as flow rate, head,
pressure distribution, forces and torques characteristics. The flow field inside the
pump are visualized using the ParaView utility of the OpenFOAM. The velocity
vectors, static pressure across the domain is plotted and shown. The presence of
blockage in the centrifugal pump results in the decrement of the static pressure near
the inlet region thus increasing the change in static pressure across the fluid domain.
The maximum flow velocity near the outlet section of the pipe gets reduced which
results in the decrement of the discharge at the outlet. The presence of crack reduces
the static pressure in overall domain. With increase in crack depth the static pressure
decreases risking to the occurrence of cavitations. These results conclude that
monitoring variation in pump parameters such as flow velocity and static pressure in
the pump domain helps in developing an efficient methodology for fault detection and
diagnosis system.
Description
"Pumps" are hydraulic devices that transform mechanical energy into hydraulic
energy in the form of pressure energy. The hydraulic device is referred to as a
"centrifugal pump" if the fluid's centrifugal force is used to transform mechanical
energy into pressure energy.
Centrifugal pumps are designed to increase the fluid pressure. Centrifugal pumps are
rotary devices with two main components: an impeller and a volute casing. The
impeller is the rotary component which consists of a series of curved blades while the
volute casing is the static component. In principle, the centrifugal pumps use a
rotating impeller to give rotation to the fluid developing dynamic pressure which
enable the lifting of the fluids from the lower level to a higher level. The liquid enters
the pump through the eye of the impeller and is pushed by the impeller radially into
the volute
Keywords
MRF approach