Sensitivity of spinning process with flow-induced crystallization kinetics using frequency response method

Abstract

The sensitivity of the low-and high-speed spinning processes incorporated with flow-induced crystallization has been investigated using frequency response method, based on process conditions employed in Lee et al. [1] and Shin et al. [2,3]. Crystallinity occurring in the spinline makes the spinning system less sensitive to any disturbances when it has not reached its maximum onto the spinline in comparison with the spinning case without crystallization. Whereas, the maximum crystallinity increases the system sensitivity to disturbances, interestingly exhibiting high amplitude value of the spinline area at the take-up in low frequency regime. It also turns out that neck-like deformation in the spinline under the high-speed spinning conditions plays a key role in determining the sensitivity of the spinning system.

Verification of the Influence of Processing History through Comparing High-Speed Melt Spinning Behavior of Virgin and Recycled Polypropylene

“…Generally, in the melt spinning process at high take-up velocities, after gradual thinning of the spin-line, an abrupt and sharp decrease in diameter occurs at a certain point. This behavior is called 'neck-like deformation' [20][21][22][23][24][25][26][27]. Neck-like deformation is known to play an important role in the stabilization of the melt spinning process and the development of the fiber structure [25,26].…”

“…This behavior is called 'neck-like deformation' [20][21][22][23][24][25][26][27]. Neck-like deformation is known to play an important role in the stabilization of the melt spinning process and the development of the fiber structure [25,26]. After completion of the neck-like deformation, the additional decrease in diameter is minimal.…”

Modeling the melt blowing of viscoelastic materials

“…In frequency response analysis, one imposes small sinusoidal disturbances in time on the top of a steady -state and then uses the linearized equations to determine the system output. Frequency response analysis has been used extensively to study melt spinning (Denn, 1980;Kase and Araki, 1982;Devereux and Denn, 1994;Jung et al, 2002Jung et al, , 2004Kohler and McHugh, 2007;Yun and Shin, 2010). Resonance peaks are found near the frequencies corresponding to the imaginary parts of the eigenvalues obtained from linear stability analysis.…”

Frequency response analysis of nonisothermal film blowing process using transient simulations

“…Variation of the output state variables depends on the frequency and type of an imposed disturbance. Their responses obtained from linearized sensitivity24–30 or direct transient simulation31 methods are plotted against frequency in a Bode diagram. Sensitivity studies have been extensively carried out in fiber spinning processes, since the first reports by Denn24 and Kase and Araki 25.…”

“…Sensitivity studies have been extensively carried out in fiber spinning processes, since the first reports by Denn24 and Kase and Araki 25. Compared to the fiber spinning case,24–30 there have been few reports on the sensitivity of film blowing process because of its complicated dynamics. McHugh and coworkers10, 29 eloquently explained the effect of crystallization on the sensitivity using a two‐phase fluid model.…”