Air and water jets in textile processing
thesisposted on 26.11.2015, 13:59 by Memis Acar
This thesis describes original engineering research which aimed to establish fundamental understanding of various textile processes and to search for solutions to the associated problems. First, the particulars of the candidate are given, followed by a list of the publications included in the submission and the summary of each paper detailing the aims and achievements of the work. In this thesis, contributions in the following areas are described: 1. Air-jet texturing and intermingling: this section, which contains nearly half of the papers, reports the research in the field of air-jet texturing of continuous filament yarns and intermingling of false-twist textured yarns. Theoretical and experimental investigations of the supersonic air flow, its interaction with the filament yarn and the effect of process parameters on the properties of the textured yarn are reported. This research established a clear understanding of the mechanism of the loop and entanglement formation in the air-jet texturing and the air-intermingling processes. Improvements to both processes have been suggested and more efficient and cost effective nozzles have been designed and evaluated. 2. Yarn characterisation: development of digital image processing and analysis techniques for objective, non-invasive and accurate assessment of the structural properties of the air-jet textured yarns is reported. The research has been extended to include the measurement of nip frequency and regularity of the air-intermingled yarns, as well as the yarn hairiness, evenness and twist of the conventional spun yarns. 3. Water-jet and thermal bonding of nonwovens: experimental research into the nonwoven fabric formation using very fine high-pressure water jets and modelling of the thermal bonding of fibrous webs by passing hot-air flow through them, mostly in collaboration with North Carolina State University, are reported. Models developed provide an essential tool for more efficient process, product and machine design. 4. Finally, this short section reports various other textile engineering research including the use of pulse lasers to fuse false-twist textured yarns to impart fused nodes (nips), the fibre opening, straightening and transportation using high-speed air flow in the open-end spinning process, and the design, development and construction of a novel circular warp knitting machine. The interrelationship between the publications is explained and reference to the work of the others in the field is given where appropriate. The contributions that the publications have made and the role that they played in advancing the knowledge in the research field and the impact they have made on other researchers are stated. The papers submitted represent research projects which were pioneering in their field and often inspired other researchers.
- Mechanical, Electrical and Manufacturing Engineering