Changes in Capture Efficiency Due to Folding A problem for MPI 2013 Worcester Polytechnic Institute Matt Lucey and Yueyang Shen June 17, 2013 About Pall Corporation Leader Leader in in Filtration, Filtration, Separation and Purification Purification Scientific, Scientific, technology and advanced advanced engineering engineering company company Founded
Founded in in 1946 1946 Global Global Footprint Over Over 10,000 Employees $2.7B $2.7B Annual Annual Revenue Revenue year year ending ending Aug. Aug. 2012 2012 Capture Efficiency Lucey & Shen June 17, 2013 2 of 10
Cast and Expanded Membranes Pall's cast and expanded membranes have the following benefits. Micron efficiency rating from 100 m down to ultrafiltration levels in liquids. Fast flow rates resulting from highly porous and asymmetric structures. Wide variety of polymer offerings. Excellent chemical resistance, thermal characteristics, and surface treatments . PTFE - Sample of Micro-Structure Capture Efficiency Lucey & Shen June 17, 2013 3 of 10 Media Applications
Flat Sheet Devices Laid-Over Pleat (LOP) Cartridge Contributions to Variable Performance for the Current Problem Pre-stress of media during production Plastic deformations from pleating Creep Relaxation Temperature while Pleating Phase Transition Thickness of Media / Membranes (stack-up) Capture Efficiency Lucey & Shen June 17, 2013
4 of 10 Problem Statements How does large deformation of a membrane (PTFE) strip, with a 3D random nodeand-fibril distribution, affect the capture of particles? What happens over time due to stress relaxation? Assumptions Mechanical Capture of Particles Anisotropic Material in 2 directions thickness is uniform Non-Linear Material Behavior Random Pore Size Distribution 20 nanometers Suspended Particles* are Mono-dispersed 20 nanometers Drainage and Support layers have no effect on capture
Drainage Material : Elastic Modulus = 50000 psi ; Poissons Ratio = 0** * Liquid is DI water with surfactant ** The true value for Poissons Ratio actually depends on the orientation of the strands Capture Efficiency Lucey & Shen June 17, 2013 5 of 10 A Brief Literature Survey Hu-Hai Guo, et al. Journal of Applied Polymer Sciences, 116 (2010) 1124-1130 Described in details the two-step biaxial stretching operation for PTFE membrane preparation. Proposed a FEA model to study the stress and displacement distribution of the biaxially stretched PTFE membrane. Drawback: PTFE base sheet was considered mechanically isotropic. No structure information.
K Kurumada, et al. Journal of Membrane Sciences, 149 (1998) 51-57 Studied the morphology and its structure formation of the PTFE porous membranes fabricated through the steady-rate biaxial stretching operations. Drawback: Only explanation but no modeling given for the generation of structure of PTFE. K Evans, et al. Journal of Physics D: Applied Physics, 22 (1989) 1883-1887 Described a simple model for the PTFE microstructure to account for its highly anisotropic and negative Poisson's ratio. Drawback: No allowance for material elasticity are considered in this model. Reason to mention: good beginning point to build PTFE structure model. Capture Efficiency Lucey & Shen June 17, 2013 6 of 10 A Brief Literature Survey
T Suwa, et al. Journal of Applied Polymer Science, 17 (1973) 3253-3257 Melting and crystallization behavior of the virgin PTFE was studied using a DSC. Reason to mention: heating and cooling process are involved during PTFE manufacturing and pleating process. E Brown, et al. Polymer, 48 (2007) 2531-2536 Described temperature-pressure phase behavior of crystalline PTFE. PTFE shown to respond to uniaxial deformation by undergoing a crystalline phase transition. Detailed Teflon PTFE bulk properties: http://www.rjchase.com/ptfe_handbook.pdf Capture Efficiency Lucey & Shen June 17, 2013
7 of 10 Problem Schematics What happens in the deformed region? Neutral Axis Shift depending on layer thicknesses Simple Bending Membrane Tension Membrane Compression Capture Efficiency Lucey & Shen June 17, 2013 8 of 10 Schematic of Challenge Particles Trapped by PTFE Membranes PTFE Fibrils
PTFE Nodes Capture Efficiency Lucey & Shen Challenge Particles June 17, 2013 9 of 10 Schematic of an FEA Model Capture Efficiency Lucey & Shen June 17, 2013 10 of 10
IUC London DoS Lead . Sarah Mackmin-Woodis the London DoS Lead and works on MiDoS Capacity and the Mental Health workstream. Sarah has most recently been working as Head of Urgent Care in East Sussex but has a background in...
Serve Louisiana taxpayers fairly and with integrity by administering property tax laws. Provide the general public with a centralized place to obtain property tax information and confidence to the taxpayers that their assessments are fair and equitable.
UNITED NATIONS INDUSTRIAL DEVELOPMENT ORGANIZATION UNIDO's Programme for Industrial Upgrading and Restructuring The CHALLENGE TO PRODUCE GOODS AND SERVICES The CHALLENGE TO IMPROVE QUALITY AND PRODUCTIVITY It is a Total Business (company-wide) concept rather than just the "rationalization of production":...
This effect is exactly what was seen in the GUSTO 1 trial of 41,000 patients that established the superiority of tPA over streptokinase. The profile of the patient at high risk for bleeding is characterized by older age, renal failure,...
"University Values - University Integrity" August 26-28, 2010 Trier, Germany Integrity in Higher Education: Quality Improvement versus Ranking Improvement Nachum Finger Ben-Gurion University of the Negev and the Council for Higher Education, Israel
SSARS No. 24 issued in May 2018. Effective for compilations and reviews of financial statements for periods ending on or after June 15, 2019. Provides new guidance for an accountant who performs a compilation or review in either of the...
Analytical Structure ... 1263-1328 Deobandi Islam returning to original 1867 British-held India sources of Islam anti-colonial Islam Abu al-Ala Maududi Abdullah Azzam 1903-1979 Palestinian 1941-1989 Pakistan Intellectual mentor of OBL Purification of Islam is a key to independence from British...
Ready to download the document? Go ahead and hit continue!