|Modeling Flexible Fiber-Motion and
Orientation: Comparison Between Classical Rigid Fiber Models and the
Objective and Background
reinforced composites play a significant role in various industrial
applications. Understanding ho
fiber configuration changing in the polymer matrix during processing
influences the properties of the final composites is critical for
material design as well as material property control. By using modeling
and numerical methods to simulate the material manufacturing process,
material properties can be predicted in a way of much lower cost and
higher efficiency compared to experimental methods. There have been
several models proposed trying to acquire the evolution of long fiber
motion and orientation in polymer flow during processing, among which
rod chain model by representing a single long fiber as a series of
perfectly rigid rods, each of which made of a certain number of beads,
was verified to be of reasonable efficiency and simple construction
based on fluid dynamics. The objective of this research is to
develop a mathematical model to simulate the motion of a large number
of long flexible fibers in various flow conditions, based on which
various bulk material properties at any time of processing are
predicted by the properties of component materials and
initialconditions of processing.
Flexible fiber model employed in the present study (shown in the figure
below) is that of Wang et al. (European Journal of Mechanics B/Fluids
25 (2006) 337–347), where the flexible fiber is composed of a series of
rigid beads forming individual rods and the rods are connected by
torque and force joints (hinges).
Rod chain model yields the same results as that obtained from Jeffery’s
equation with respect to fiber motion period and orbits when fiber is
perfectly rigid. This is demonstrated in the figure below where
the motion is compared for a flexible and a rigid fiber
(a) N = 1
, Nr = 10
, ar = 10
, rc = 21.13
direction vector p = [1 0 0]T
(b) N = 1
, Nr = 30
, ar = 30
, rc = 4.75
initial unit direction vector p = [1 0 0]T
Publications From This Work
- Flexible Fiber Waviness as a Role in Fiber
Motion Simulation and Material Property Prediction. C. Zhang* and D.A.
Jack. Early Career Technical
Conference, Fayetteville, Arkansas, March 2011.
- Fiber Orientation
for Suspensions of Long
Fibers: Comparison of Rigid and Flexible Models. C. Zhang* and D.A.
Jack. Proceedings of the Society of Rheology's 82nd Annual Meeting,
Santa Fe, New Mexico, October, 2010.
- Modeling of
Flexible Fiber Motion and
Orientation in Simple Shear Flow: A Comparison between Rod-Chain Model
and Jeffery's Equation. C. Zhang* and D.A. Jack. Proceedings of ASME
IMECE'10, Vancouver, British Columbia, Canada, November, 2010.
- Flexible Fiber
Suspension Orientation Model
Predictions: Comparison Between Rod-Chain Model and Classical Jeffery's
Rigid Ellipsoid Model. C. Zhang* and D.A. Jack. Early Career Technical
Conference, Tulsa, Oklahoma, March 2010.