Prediction of Fiber Diameter of Melt Blowing Nonwovens Produced by Dual Slot Inset Sharp Die

Author(s):  
Zhao Bo
Keyword(s):  
2019 ◽  
pp. 152808371986693 ◽  
Author(s):  
Changchun Ji ◽  
Yudong Wang ◽  
Yafeng Sun

In order to decrease the fiber diameter and reduce the energy consumption in the melt-blowing process, a new slot die with internal stabilizers was designed. Using computational fluid dynamics technology, the new slot die was investigated. In the numerical simulation, the calculation data were validated with the laboratory measurement data. This work shows that the new slot die could increase the average velocity on the centerline of the air-flow field by 6.9%, compared with the common slot die. Simultaneously, the new slot die could decrease the back-flow velocity and the rate of temperature decay in the region close to the die head. The new slot die could reduce the peak value of the turbulent kinetic energy and make the fiber movements more gradual. With the one-dimensional drawing model, it proves that the new slot die has more edge on the decrease of fiber diameter than the common slot die.


2021 ◽  
Vol 36 (4) ◽  
pp. 403-409
Author(s):  
K. Iiba ◽  
W. Takarada ◽  
T. Kikutani

Abstract In the melt blowing process, the molten polymers extruded from nozzles are elongated by high-velocity and high-temperature air flow. In this study, with the aim of stabilizing the melt blowing process for producing nonwoven webs with fine diameter fibers, the effect of the control of polymer rheology by the introduction of either low melt flow rate (MFR) polypropylene (PP) or long chain branched PP (LCB-PP) to regular high MFR PP was investigated. Introduction of low MFR PP into regular PP increased shear viscosity and fibers of larger diameter were produced in the melt blowing process, while introduction of low MFR LCB-PP suppressed the elongational viscosity reduction with the increase of strain rate, and eventually spinning was stabilized. It was found that the blending of an optimum amount of LCB-PP to regular PP caused the stabilization of the melt blowing process. As a result, the formation of nonwoven webs consisting of fine fibers of rather uniform diameter distribution could be achieved.


2003 ◽  
Vol os-12 (2) ◽  
pp. 1558925003os-12 ◽  
Author(s):  
Randall R. Bresee ◽  
Wen-Chien Ko

Experimental measurements are presented to provide phenomenological insight into the commercial melt blowing process. In particular, we discuss the following experimental measurements obtained at various die-collector locations: fiber diameter, fiber velocity, air velocity, fiber acceleration, fiber entanglement, fiber temperature, birefringence, wide-angle x-ray diffraction and small-angle x-ray scattering. Our discussion focuses on how these measurements provide insight into fiber formation during melt blowing.


2015 ◽  
Vol 27 (1) ◽  
pp. 91-98 ◽  
Author(s):  
Bo Zhao

Purpose – The purpose of this paper is to varify, the air drawing model and the air jet flow field model of dual slot shape die for a polymer in a melt blowing process were established, by the experimental results obtained with experimental equipment. Design/methodology/approach – The air jet flow field model is solved by introducing the finite difference method. The air drawing model of polymers in the melt blowing process was studied with the help of the simulation results of the air jet flow field. Findings – The higher air initial velocity and air initial temperature can all yield finer fibers and causes the fibers to be attenuated to a greater extent. Originality/value – The predicted fiber diameter agrees well with the experimental result, which verifies the reliability of these models. At the same time, the results also reveal the great potential of this research for the computer-assisted design of melt blowing technology.


2011 ◽  
Vol 179-180 ◽  
pp. 668-671 ◽  
Author(s):  
Li Li Wu ◽  
Ting Chen

Nonwoven samples are collected from industrial equipments in four nonwoven factories. The processing parameters and equipment parameters are also obtained. The fiber diameters of the nonwoven samples are measured by using the image analysis method and compared with the predicted fiber diameters by solving the polymer air drawing model. The results show that the predicted fiber diameters coincide with the measured fiber diameter very well, which confirms that the polymer air drawing model is effective in predicting fiber diameters of nonwoven fabrics produced by industrial equipments in nonwoven factories. The results reveal the practical value of this theoretical research on the melt blowing technology.


2011 ◽  
Vol 148-149 ◽  
pp. 465-469 ◽  
Author(s):  
Hua Jun Chen ◽  
Ting Chen ◽  
Li Li Wu

Melt blowing process can produce superfine fibers. In this processs, the polymer is drawn by high velocity hot air. Lagrange method is empolyed to establish and solve the polymer drawing model. The fiber diameter and vibration are predicted with the model. The predicted fiber diameter concides with the experimental data. The fiber vibration becomes larger and larger with the increase of the die-to-collector distance. Computer simulations show that higher initial air velocity and higher initial polymer temperature can producefiner fibers while initial airtemperature contribute little to the polymer drawing.


2010 ◽  
Vol 121-122 ◽  
pp. 138-142
Author(s):  
Ting Chen ◽  
Meng Sun ◽  
Li Li Wu

The polymer air drawing model of polyamide melt blown nonwoven fabrics is established. The predicted fiber diameter coincides with the experimental data. The effects of the processing parameters on the fiber diameter are investigated. It is found that smaller polymer flow rate, higher initial polymer temperature, larger initial air velocity and larger die-to-collector distance can all produce finer fibers while too high initial air velocity and too large die-to-collector distance contribute little to the polymer drawing of polyamide melt. The results show great perspective of this research in the field of computer assisted design of the melt blowing technology.


2004 ◽  
Vol os-13 (2) ◽  
pp. 1558925004os-13 ◽  
Author(s):  
Eric M. Moore ◽  
Robert L. Shambaugh ◽  
Dimitrios V. Papavassiliou

Online measurements of the fiber diameter distribution during a melt blowing process were taken using a new laser diffraction technique. This technique measured both the attenuation of the fibers as well as entanglement of the fibers into bundles at large distances from the die. A pilot scale unit with a 20.3 cm (8 inch) slot die was used for the studies. Commercial polypropylene polymer was used. Both the spin-line attenuation and fiber bundling were measured as a function of position both below and across the die face.


2006 ◽  
Vol 1 (1) ◽  
pp. 155892500600100 ◽  
Author(s):  
Randall R. Bresee ◽  
Uzair A. Qureshi

We are continuing an effort to quantitatively measure the influence of processing variables on the structure of polypropylene melt blown webs. In this paper, we report experimental measurements of the influence of die-to-collector distance, primary airflow rate, die temperature, collector speed and resin throughput rate on the diameter of fibers in fully-formed webs. This enabled us to quantitatively compare the influence of these processing variables on fiber diameter as well as to achieve greater understanding of the melt blowing process.


Sign in / Sign up

Export Citation Format

Share Document