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Information × Registration Number 0221U106725, 0121U113770 , R & D reports Title Knitted Materials for Personal Protective Equipment Against Mechanical and Flame Damages (Acronym - PERPROKNIT) popup.stage_title Head Halavska Liudmyla Ye., Доктор технічних наук Registration Date 17-12-2021 Organization Kyiv National University of Technologies and Design popup.description2  Object of research: the process of modeling the structure of knitted fabric from high-strength threads. The aim of the work is to simulate the structure and properties of knitted fabric from raw materials of increased strength, taking into account deformation under the action of force loads and loss of strength of threads in accordance with the knitting conditions. In the course of the work, a mathematical apparatus was developed for describing the geometry of the thread in the loop and 3D models of stockinet and rib 1х1 knitted fabrics were constructed from para-aramid and polyethylene threads in a conditionally equilibrium state and at maximum uniaxial tension in the course or wale direction. By simulating the process of air passage in the Autodesk CFD Simulation environment and comparing the results obtained with the data of a laboratory experiment using prototypes of knitwear, the created 3D models were verified (deviations within 7.2%). The regularities of the influence of the number of cyclic loads "tension - bending - friction" on the loss of strength of para-aramid and polyethylene threads have been established. The obtained correlation dependences adequately describe this process and make it possible, at the stage of designing the knitwear structure, to determine the number of load cycles, which corresponds to the loss of thread strength at given knitting parameters. To calculate the number of load cycles that determine the limiting value (20%) of the loss of strength of polyethylene and para-aramid threads during their processing on knitting equipment in accordance with the selected linear density, it is proposed to use a specific coefficient depending on the type of super-strong thread and corresponding to the number of cyclic loads per unit its linear density. Its value has been experimentally established. Product Description popup.authors Ielina Tetiana V. Bezsmertna Viktoriia I. Bоbrova Svitlana Yu. Haranina Olga Oleksandrivna Dmytrenko Liudmyla A Dmytryk Oksana M Kryzhanovska Oleksandra P Markhai Maryna A Makhinia Tetiana O. Sipotenko Vira F Kharchenko Yulia M popup.nrat_date 2021-12-17 Close