Table of Contents
Journal of Fluids
Volume 2014 (2014), Article ID 241010, 7 pages
http://dx.doi.org/10.1155/2014/241010
Research Article

Numerical Characterization of the Performance of Fluid Pumps Based on a Wankel Geometry

Institute of High Performance Computing, 1 Fusionopolis Way, No. 16-16 Connexis, Singapore 138632

Received 2 June 2014; Revised 27 August 2014; Accepted 16 September 2014; Published 30 September 2014

Academic Editor: Yanzhong Li

Copyright © 2014 Stephen Wan et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

The performance of fluid pumps based on Wankel-type geometry, taking the shape of a double-lobed limaçon, is characterized. To the authors’ knowledge, this is the first time such an attempt has been made. To this end, numerous simulations for three different pump sizes were carried out and the results were understood in terms of the usual scaling coefficients. The results show that such pumps operate as low efficiency (<30%) valveless positive displacements pumps, with pump flow-rate noticeably falling at the onset of internal leakage. Also, for such pumps, the mechanical efficiency varies linearly with the head coefficient, and, within the onset of internal leakage, the capacity coefficient holds steady even across pump efficiency. Simulation of the flow field reveals a structure rich in three-dimensional vortices even in the laminar regime, including Taylor-like counterrotating vortex pairs, pointing towards the utility of these pumps in microfluidic applications. Given the planar geometry of such pumps, their applications as microreactors and micromixers are recommended.