Viscous pumps: Comparative assessment of effectiveness

Abstract

A classification of the different viscous pump embodiments and a survey of the application areas are made. A dimensionless number is newly introduced here, and it is suggested that this be used in evaluating the comparative effectiveness of viscous pumps of different configurations. The effectiveness is evaluated for viscous pumping devices developed over the last four decades and for which sufficient data and experimental test results are available. It is shown that these pumps could be broadly categorized into effective and much less effective types. An enumeration of possible design pitfalls is given for the latter types. The findings of the present paper are deemed useful to design engineers in their endeavour to assess the effectiveness of existing viscous pumps and in developing new ones.