Impeller

About: Impeller is a research topic. Over the lifetime, 45119 publications have been published within this topic receiving 242579 citations. The topic is also known as: Impeller, impellar & blades.

Numerical Simulation of the Dynamic Effects Due to Impeller-Volute Interaction in a Centrifugal Pump

Abstract: We show the capability of a numerical simulation in capturing the dynamic and unsteady flow effects inside a centrifugal pump due to the impeller-volute interaction. The object of the study is a commercial centrifugal water pump with backward curved blades, which is built within a vaneless single tongue volute. For the numerical simulation, the viscous Navier-Stokes equations are handled with an unsteady calculation and the sliding mesh technique is applied to take into account the impeller-volute interaction. In keeping the unsteady terms of the equations active it is possible to correctly simulate the effects of the blade passage in front of the tongue and both the flow and pressure fluctuations induced. Time averaged numerical results are compared with the experimental performance curve. The numerical flow analysis allows the study of different variables which are always difficult to measure experimentally. The dynamic variables obtained with the proposed numerical model are compared with the experimental data

Electronic component cooling apparatus

Abstract: An electronic component cooling apparatus capable of permitting a sufficient amount of air to be fed to an electronic component to be cooled An impeller which includes a plurality of blades for sucking air from one side in an axial direction of a revolving shaft of a motor is fixed on a rotor of the motor A casing having a cylindrical cavity defined therein in which the motor and impeller are received is constructed of a peripheral wall arranged so as to surround the impeller and a closing wall for closing an end of the cavity on the other side in the axial direction The peripheral wall is formed at a portion thereof in proximity to an end thereof on the one side with a lateral discharge port through which air suckedly introduced into the cavity is discharged so that a surrounding portion for surrounding a whole circumference of the impeller is left at a portion of the peripheral wall in proximity to an end on the other side The casing is provided with a spacer means for providing an interval between the casing and an opposite member

Short communication Shear rate in stirred tank and bubble column bioreactors

Abstract: A rigorous theoretical analysis is used to show that for both Newtonian and non-Newtonian power law fluids agitated in stirred vessels, the average shear rate γ in the fluid is a function of the rotational speed N of the impeller, as follows: γ = constant · N (laminar flow) γ = constant · N 3/2 (turbulent flow). Only in turbulent flow, the proportionality constant in the above equation depends on the flow index and the consistency index of the power law fluid. The above equations derived by theoretical reasoning are in excellent agreement with the long established empirical art. In bubble columns, the average shear rate depends on the superficial gas velocity Ug, as follows: