Selected Projects

Numerical Simulations and Parameter Optimization for Rotary Draw Bending of Tubes
Date: 06.2007–06.2008 My role: main modeling analyst Rotary draw bending is the metal forming process widely used in aerospace and automotive industries to form straight metal tubes into designed spatial geometric shapes. Viewed from the perspective of analysis, the process is severely nonlinear from multiple sources—the geometric nonlinearity due to the large rotation, the material […]

Material Calibration of Spunbond Nonwoven Using Inverse FEM
Date: 11.2008 My role: modeling analyst and experimenter The in-plane orthotropic material model works quite well in capturing the elastic behavior of spunbond nonwoven under small deformation1. Although the model is a basic one in elasticity, some material constants such as the Poisson’s ratio and shear modulus are difficult to measure accurately for nonwoven. We […]

Measurement of Web Surface Profiles Using Fringe Projection
Previous methods used to measure surface profiles in web handling area are hard to obtain high accuracy and efficiency simultaneously. We explored the fringe projection technique and developed a system that used a commercial projector and a digital camera and produced non-contact, full-field measurement of surface profiles with high accuracy. We applied the system to […]

Dynamic Simulation of Nip Mechanics in Web Transiting
A nip set consisting of two nip rollers is widely used on web lines to adjust web line tension, feed in inks for printing, conduct lamination, and etc. The nip rollers may have cover material such as rubber or foam. Here we are curious how the velocities and tension are changed by the different configuration […]

Dynamic Simulations of Instability of Web due to Misaligned Roller
One of the fundamental rules in web handling is a web always tends to enter a cylindric roller normally—the middle of web will be perpendicular to the axis of the roller. When a roller is misaligned in a web line, the web will steer laterally on the roller until a normal entry condition is achieved, […]

Wound-on-tension of Winders with Nip Rollers
The Wound-On-Tension (WOT) is the tension in the outermost lap of a winding roll during winding. It is the most influential input that determines the wound roll stresses. WOT is dependent of winder types, material properties of web, winding parameters, and geometry of winders. We developed an explicit model to account for all those aspects. […]

Dynamic Simulations of Lateral Mechanics of Web Camber
If a web laying on a plane surface does not have a perfectly flat and straight shape, it has camber. The cambered web laying on the plane surface that flattens but forms a curved shape has a uniform camber; the cambered web that has does not flatten on the plane and forms a baggy lane […]

Eulerian Results Extractor for Abaqus
Solid mechanics simulations are mainly based on the finite element method that adopts the Lagrangian description—in which computational mesh is carved in the material body and deforms with the body. In post-processing, analysts naturally form their interpretation from results at Lagrangian mesh, for example, displacements and reaction forces at nodes, stresses and strains at integration […]