Bryan Haynes, Ph.D.
Senior Technical Director, Global Nonwovens, Kimberly-Clark Corporation
BIOGRAPHYBryan received his B.S. and M.S. in Aerospace Engineering and Ph.D. in Mechanical Engineering from the University of Tennessee at Knoxville. His graduate work specialized in the aerodynamics and polymer processing of the meltblowing process. After teaching Engineering at UT, he joined Kimberly-Clark in 1992 as a Research Scientist. At K-C, he has held various positions in research and engineering. Bryan has published several papers and has obtained 43 U.S. Patents and 13 Trade Secrets during his Kimberly-Clark career. He currently holds the position of Director of Research and Engineering in Global Nonwovens. His team is responsible for the front end innovation portfolio and prototyping capabilities including the pilot facilities supporting Kimberly-Clark’s various businesses. Bryan serves on the External Advisory Board for the School of Materials Science & Engineering at the Georgia Institute of Technology and on the Board of Directors as Secretary for Georgia FIRST which is a non-profit organization that supports STEM programs in Georgia. Bryan is married with two daughters.
10:35 am - 12:05 pm
A New Generation of Fine Fiber Processing for Filtration
Challenges for Submicron Meltblown: A Computational Study of the Inherent Jet Instabilities within the Nozzle and the Impact on Filament Formation
Meltblown is used extensively in nonwoven materials. The micron scale fibers coupled with the tortuous pore structure result in an ideal barrier or filtration layer. The process evolution over the past couple of decades has been driven by the ability to produce finer fiber at higher throughputs to minimize cost. It is widely known that submicron fibers can be produced at lower total throughputs per beam which for most instances is undesirable due to cost. Processing at lower throughput per capillary and increasing the capillary count is an obvious means for increasing the total throughput. There are several challenges with operating at higher capillary density. How small of a capillary can be formed? What is the highest capillary density before the molten fiber streams bump creating defects? How does the air turbulence impact extrusion, fiber formation? A computational study was initiated to better understand the effect of the process air on the process. Velocity, turbulence and vorticity were considered when studying how to better control the jet instabilities. This paper will show how a single layer screen placed upstream of the nozzle exit can significantly improve jet stability. Improved stability may enable operating at higher capillary densities and/or process air flow to form finer fiber meltblown.