Eventos Anais de eventos
COBEM 2017
24th ABCM International Congress of Mechanical Engineering
Influence of operational conditions on the trajectory of an air bubble inside a centrifugal pump
Submission Author:
Edgar Ofuchi , PR
Co-Authors:
FELIPE CARLOS ANCAJIMA JIMENEZ, Renzo Harkov Gutierrez Sabino, Henrique Stel, Dalton Bertoldi, Moisés Marcelino Neto, Rigoberto Morales, Edgar Ofuchi
Presenter: Edgar Ofuchi
doi://10.26678/ABCM.COBEM2017.COB17-1217
Abstract
Centrifugal pumps operate below their desired capacity when subject to gas-liquid flows. Several studies were developed to understand the effect of gas on the pump performance, but just a few are interested in understanding the gas phase dynamics inside the pump. In this sense, this work presents an experimental and numerical study on the influence of operational conditions on the bubble trajectory in a centrifugal pump. High-speed photography is used to track the motion of isolated bubbles inside the pump impeller. Numerically, the flow of bubbles inside the pump first stage is simulated using an Euler-Lagrange “one way” approach. Comparison between numerical and experimental results shows a good agreement. Results reveal that the operating conditions have an important influence on the bubble trajectory. Higher flow rates help to drag the bubbles outside the impeller, while increasing the rotational speed can force the bubbles back to the pump inlet. The motion of bubbles is also very sensitive to their diameter and their entering position inside the impeller. Study of the bubble dynamics as influenced by different operating conditions is key to understand the mechanisms behind the performance degradation of pumps with gas-liquid flows.
Keywords
pump, Gas-liquid, bubble motion, experimental, numerical
