A Model for Multifilament Melt-spinning Processes Incorporating Filament/quench-air Interaction and Boundary Layer Coalescence - read free eBook in online reader or directly download on the web page. Select files or add your book in reader. Download and read online ebook A Model for Multifilament Melt-spinning Processes Incorporating Filament/quench-air Interaction and Boundary Layer Coalescence write by Robert Lindsey Lowe. This book was released on 2005. A Model for Multifilament Melt-spinning Processes Incorporating Filament/quench-air Interaction and Boundary Layer Coalescence available in PDF, EPUB and Kindle. Abstract: Multifilament melt spinning refers to the process in which molten polymer is extruded through a spinneret, divided into an array of individual filaments, and cooled to solidification by a fan-induced quench-air stream. The interaction of the quench-air stream with the filaments in melt-spinning processes causes the filaments to cool and the quench air to heat and slow so that each row of molten filaments in the array experiences different quench conditions. Since the properties of solidified fibers depend strongly on quench conditions, this variation results in nonuniform fiber properties from filament to filament. Quantifying and minimizing this variation is of great importance to the polymer fiber industry. A model for multifilament melt-spinning processes is developed in this paper which predicts the variation of fiber properties within the array and provides a tool for optimizing the process (e.g. minimizing fiber-to-fiber variation). The multifilament melt-spinning model developed in this paper couples a model for a single filament in a specified quench environment with filament/quench-air interaction models for three different domains, namely the stagnant boundary layer at the spinneret face, the region where the quench-air stream passes through the filament array, and the coalesced boundary layer. Material properties, process conditions, and first-row quench-air temperature and velocity profiles serve as input to the complete multifilament melt-spinning model. The model then computes the first-row filament response and the quench conditions experienced by the second row, then the second-row filament response and the quench conditions experienced by the third row, and so on.
Two Dimensional Modelling of Pet Melt Spinning
Two Dimensional Modelling of Pet Melt Spinning - read free eBook in online reader or directly download on the web page. Select files or add your book in reader. Download and read online ebook Two Dimensional Modelling of Pet Melt Spinning write by Tyrone Kotze. This book was released on 2010-12-01. Two Dimensional Modelling of Pet Melt Spinning available in PDF, EPUB and Kindle. This work begins with an in depth cover of the current literature surrounding modelling techniques used to simulate the melt spinning procedure. A one dimensional single filament model developed by previous workers is used to construct a multifilament model which enables a conservative estimate to be made on the effects of heat transfer limitations on the quality of PET yarn. Properties modelled include crystallinity, viscosity, temperature, velocity, fibre diameter and force. Variables investigated include quench air temperature and velocity, polymer extrusion rate and temperature as well as fibre take-up speed. Results showed quench air flow rate to have the largest influence on final property uniformity. Low polymer extrusion rates resulted in a lower degree of non-uniformity in final fibre properties. The model developed showed non-uniform quench air thermal gradients to have adverse effects on the quality of as-spun yarn.
Process for the Melt Spinning of Fine Multifilament
Process for the Melt Spinning of Fine Multifilament - read free eBook in online reader or directly download on the web page. Select files or add your book in reader. Download and read online ebook Process for the Melt Spinning of Fine Multifilament write by E. Ichihashi. This book was released on 1985. Process for the Melt Spinning of Fine Multifilament available in PDF, EPUB and Kindle.
Process for Melt Spinning of Thick Multifilament Yarn
Process for Melt Spinning of Thick Multifilament Yarn - read free eBook in online reader or directly download on the web page. Select files or add your book in reader. Download and read online ebook Process for Melt Spinning of Thick Multifilament Yarn write by M. Yokozawa. This book was released on 1987. Process for Melt Spinning of Thick Multifilament Yarn available in PDF, EPUB and Kindle.
Melt Spinning of Continuous Filaments by Cold Air Attenuation
Melt Spinning of Continuous Filaments by Cold Air Attenuation - read free eBook in online reader or directly download on the web page. Select files or add your book in reader. Download and read online ebook Melt Spinning of Continuous Filaments by Cold Air Attenuation write by Jun Jia. This book was released on 2010. Melt Spinning of Continuous Filaments by Cold Air Attenuation available in PDF, EPUB and Kindle. Traditionally ultrafine fibers below 1 dpf are produced by extrusion followed by mechanical drawing. A modified melt spinning apparatus with high-speed air nozzle was designed and fabricated to produce continuous polypropylene filaments by cold air drawing only. With this setup, the fiber is quenched and simultaneously attenuated by a symmetric cold air jet. Since the formation of fiber structure is highly dependent on the processing conditions, the new process will provide a unique operation window to study fiber attenuation and structural formation under high-speed cold air drawing. Based on computational fluid dynamics simulation results, a parametric study was carried out under different process conditions which include processing temperature, air velocity and polymer volume flow rate. Effects of changes in processing variables on the fiber diameter, molecular orientation, crystallinity, tensile strength and other properties were studied. Furthermore, a theoretical model was developed to analyze the non-isothermal fiber attenuation mechanisms. The new knowledge obtained in this study would likely yield a new process for producing innovative fiber products.
