Session: IMECE Undergraduate Research and Design Exposition

Paper Number: 114159

114159 - Impeller Blade Shape Effect on the Centrifugal Pump Performance Analysis 

The energy conversion is determined by the so-called Euler formula, which constitutes the basic principle of the operation of kinetic, rotodynamic or hydraulic turbomachinery machines. It establishes the conversion of energy between the impeller and the fluid, due to the variation of the amount of moment. This formula is based on the concepts of conservation of angular momentum and conservation of energy; correlating parameters such as the specific work, geometry and speeds in the runner.

Focusing on the geometry that this equation considers, it takes into account angles at the inlet and exit of the blades; this does not completely define the geometry of the blades. Thus, we will study the impact of independent parameter variations of those defined by Euler's equation for turbomachinery.

In this work a most common and utilized pump, using water as a working fluid, simulations have been carried out, through the SolidWorks Flow Simulation software, and we proceeded to modify the trajectory of the fluid particles, altering the curvature of the blades and taking as parameters the pressure and the velocities of the fluid.

The geometry of the channel through which the fluid flows influences the degree of turbulence developed in the flow by the fluid. A smoother curve in the design results in less turbulence, while a more pronounced curve results in more turbulence. The degree of turbulence increases as the curvature of the channel through which the fluid flows increases. Turbulent flows increase the diffusivity of the fluid, causing an increase in friction with the fluid in the layers near the rotor walls, where inertia forces are much greater than viscous forces.

Increased turbulence leads to the appearance of vortices, and the fluctuations in velocity become stronger, leading to increased vibrations in the system where the fluid is located, which is usually an undesired effect in machinery. Another problem to be analyzed is cavitation, which is a phenomenon that can occur in centrifugal pumps in regions where the pressure in the liquid falls below its water saturation pressure, forming bubbles of vapor. These bubbles can collapse violently when they reach areas of high pressure, causing damage to the pump and reducing its performance and lifespan.

This work motivates the analysis of different profiles of a pump rotor for the comparison of the results, and a correct choice of profiles with better performance regarding the undesired effects caused by turbulence. It also provides insight into the influence of channel geometry on fluid flow behavior.

 

Presenting Author: Lucas Laconich Facultad de Ingenieria-Universidad Nacional de Asuncion

Presenting Author Biography: Estudiante de Ingenieria Electromecanica

Authors:

Orlando Limousin Facultad de Ingenieria-Universidad Nacional de Asuncion
Atilio Nuñez Facultad de Ingenieria-Universidad Nacional de Asuncion
Jose Duarte Facultad de Ingenieria-Universidad Nacional de Asuncion
Lucas Laconich Facultad de Ingenieria-Universidad Nacional de Asuncion
Juan Ovelar Facultad de Ingenieria-Universidad Nacional de Asuncion
Cristhian Quintana Facultad de Ingenieria-Universidad Nacional de Asuncion
Iván Yerutá Facultad de Ingenieria-Universidad Nacional de Asuncion
Jorge Kurita Facultad de Ingenieria-Universidad Nacional de Asuncion