Pneumatic Particulate Collection System Analysis and Design

Abstract

A pneumatic particulate collection system harnesses the energy associated with the release of a compressed gas to transport particulate to a collection chamber. In an effort to improve the efficiency of a previously designed collection system, high speed imaging in conjunction with computational fluid dynamics (CFD) was utilized to highlight design deficiencies. Areas of recirculation within the collection device as well as impingement of the sampling surface were observed through the testing and CFD analysis. The basis of the improved collection system was conceived through research of pneumatic transport and the deficiencies found through testing and simulation. An improved rectangular-duct-styled system was designed in three main stages. A variety of filters used to contain the desired particulate were characterized through testing for use in simulations as well as fluids calculations. The improved system was then analyzed utilizing compressible and incompressible flow calculations and design iterations were conducted with CFD to determine the final parameters. The final design was simulated with a multiphase flow model to examine the particulate entrainment performance. The improved collection system efficiently expanded and developed the gas flow prior to the collection area to employ the particulate entrainment process. The final design was constructed with an additive manufacturing process and experimentally tested to validate the simulations and flow calculations. The testing proved that the final design operated purely on particulate entrainment and collected only the top layer of particles as simulated. The improved collection system eliminated all areas of flow recirculation and impingement of the particle bed to provide a more efficient sampling device.