Analysis of Complex Total Pressure Distortion Screens Using One-Dimensional Loss Data

Abstract

Producing a screen for use in generating an accurate, complex total pressure distortion involves solving two distinct problems. First, the basic loss characteristics of wire mesh screens must be established. Second, the interaction between multiple regions with different loss coefficients (as seen in a complex screen) must be accurately accounted for. Both tasks must be solved effectively to design an accurate screen. For the first goal, we present a comprehensive data set of correlations for the losses generated by a wire mesh, stacked on top of a “backer” support screen. While some publicly available data exist for the losses induced by a single mesh on its own, the losses in a real total pressure loss screen are dependent on the interaction between the backer and the loss meshes. As a result, the data presented here include the effects of the backer. For the second task, as flow encounters a screen composed of many meshes, it redistributes itself such that the flowrate is higher through the low-loss regions and lower through the high-loss regions. A simple parallel flow model, with appropriate physically justified assumptions, can accurately predict this redistribution, and we demonstrate its effectiveness via comparison with computational fluid dynamics and experiment.