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Search Publications by: Frederick R. Phelan Jr. (Fed)

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Displaying 1 - 25 of 47

Energy Renormalization for Coarse-Graining Polymers Having Different Segmental Structures

April 19, 2019
Author(s)
Jack F. Douglas, Wenjie Xia, Nitin K. Hansoge, Wen-Sheng Xu, Sinan Keten, Frederick R. Phelan Jr.
We apply the recently developed energy renormalization (ER) method to coarse-graining representative polymer melts having a relatively low, intermediate and high degree of glass fragility, i.e., polybutadiene, polystyrene, and polycarbonate, respectively

Energy Renormalization Method for the Coarse-Graining of Polymer Viscoelasticity

May 10, 2018
Author(s)
Jake Song, David D. Hsu, Kenneth R. Shull, Frederick R. Phelan Jr., Jack F. Douglas, Wenjie Xia, Sinan Keten
Developing time and temperature transferable coarse-grained (CG) models is essential for the computational prediction and design of polymeric glass-forming materials, but this goal has remained elusive. The dynamics of CG models are often greatly altered

Energy Renormalization to Coarse-Graining of the Dynamics of a Model Glass-Forming Liquid

February 5, 2018
Author(s)
Wenjie Xia, Jake Song, Nitin Hansoge, Frederick R. Phelan Jr., Sinan Keten, Jack F. Douglas
Soft condensed matters characteristically exhibit a strong temperature dependence of relaxation properties due to glass formation, but currently no effective temperature transferable coarse- graining method exists that allows for the prediction of their

Energy renormalization approach to coarse-graining of polymer dynamics

August 8, 2017
Author(s)
Wenjie Xia, Jake Song, Cheol Jeong, David D. Hsu, Frederick R. Phelan Jr., Jack F. Douglas, Sinan Keten
A major challenge in soft matter science is the bottom-up prediction of the temperature- dependent behavior of amorphous glass-forming (GF) polymers. Coarse-grained (CG) models derived from atomistic simulation data offer chemical specificity and access to

Bayesian Calibration of Transferable, Coarse-Grained Force Fields

April 15, 2016
Author(s)
Thomas W. Rosch, Frederick R. Phelan Jr., Paul Patrone
Generating and calibrating forces that are transferable across a range of state-points remains a challenging problem in coarse-grained (CG) molecular dynamics (MD). In this work, we present a Bayesian correction algorithm, inspired by ideas from

Bottom Up Approaches to Improved Polyolefin Measurements

February 4, 2016
Author(s)
Sara Orski, Thomas W. Rosch, Anthony Kotula, Richard J. Sheridan, Frederick R. Phelan Jr., Kalman Migler, Chad R. Snyder, Luis F. Vargas Lara, Jack F. Douglas, Kathryn L. Beers
As a class of materials, polyolefins remain the largest production volume polymer in the world, as well as a highly desirable medium from which to engineer high performance and advanced properties for new applications. After decades of research, there are

Shear and dilational interfacial rheology of surfactant-stabilized droplets

April 5, 2012
Author(s)
Jeffrey D. Martin, Kendra A. Erk, Jonathan T. Schwalbe, Frederick R. Phelan Jr., Steven Hudson
A new measurement method is suggested that is capable of probing the shear and dilational interfacial rheological responses of small droplets, those of size comparable to real emulsion applications. Freely suspended aqueous droplets containing surfactant

Interfacial effects on droplet dynamics in Poiseuille flow

April 12, 2011
Author(s)
Jonathan T. Schwalbe, Frederick R. Phelan Jr., Petia Vlahovska, Steven D. Hudson
Interfacial rheology governs many properties of emulsions, and here we report theory that accounts for and measure surface viscous and elastic forces. Stokes flow is assumed in bulk phases and a jump in hydrodynamic stress at the interface is balanced by

Carbon Nanotubes: Measuring Dispersion and Length

August 26, 2010
Author(s)
Jeffrey A. Fagan, Barry J. Bauer, Erik K. Hobbie, Matthew Becker, Angela R. Hight Walker, Jeffrey R. Simpson, Jae H. Chun, Jan Obrzut, Vardhan Bajpai, Frederick R. Phelan Jr., Daneesh O. Simien, JiYeon Huh, Kalman D. Migler
Advanced technological uses of single-wall carbon nanotubes (SWCNTs) rely on the production of single length and chirality populations that are currently only available through liquid phase post processing. The foundation of all of these processing steps

High Order Shape Functions for Finite Element Analysis

October 16, 2008
Author(s)
Frederick R. Phelan Jr.
A formalism for high-order shape functions used in finite element analysis is developed. The formalism allows the shape functions to be conveniently expressed in terms of their polynomial order p, and their derivative level k. The formalism is verified by

Mixing in Microfluidic Devices Using Oscillatory Channel Flow

February 5, 2008
Author(s)
Frederick R. Phelan Jr., N R. Hughes, Jai A. Pathak
Mixing in microfluidic devices driven by oscillatory channel flow is studied. Numerical simulation of the unsteady Navier-Stokes equations is used to investigate generation of flow controlled chaotic mixing, in which the channel geometries have stationary