Study On The Coupling Characteristics Of Airflow And Fiber Bundles In The Weft Insertion System Of Air Jet Loom

Air jet loom is a kind of shuttleless loom,which is widely used in the textile industries.It has the characteristics of high weft insertion rate,less material consumption,high production efficiency and low noise.At present,the technology of air-jet weaving on single cotton fiber is relatively mature,but the air-jet weaving technology for glass fiber,nylon and other twistless rayon bundle is not perfect enough.Therefore,the study on the motion characteristics of twistless rayon bundle in the main nozzle is of great significance to the improvement of the air-jet weaving technology of the twistless rayon.In this paper,the coupling characteristics of the airflow and fiber bundles are studied in the following aspects:(1)Physical parameters test of fiber.The physical properties of glass fiber and other textile materials are measured by high power optical microscope system and fiber bundles strength tester,and physical parameters such as load,elongation and elastic modulus of fibers are obtained.(2)The numerical simulation of the internal airflow field of improved main nozzle.The main nozzle structure is improved to adapt to twistless fiber bundles through the study on structure of main nozzle used for twisted cotton fiber.The numerical simulation of airflow field of the improved main nozzle is carried out to reveal the airflow characteristics under inlet pressures.(3)Study on the coupling characteristics of airflow and fiber bundles.A constitutive equations for single fiber and two fibers are established,and the numerical simulation method of two-phase flow coupling in the main nozzles is studied to analyse motion characteristics of single fiber and two fibers in the airflow field.(4)Experimental study.The motion of twistless fiber bundles in the main nozzle is photographed by a high-speed camera,and the displacement and velocity of the fiber are obtained.Finally,the experimental data and the results of numerical simulation are compared and analyzed,and the causes of the data error are discussed.