An analysis of the air-jet yarn texturing process. Part 4, Fluid forces acting on the filaments and the effects of filament cross-sectional area and shape Memis Acar R.K. Turton Gordon R. Wray 2134/19359 https://repository.lboro.ac.uk/articles/journal_contribution/An_analysis_of_the_air-jet_yarn_texturing_process_Part_4_Fluid_forces_acting_on_the_filaments_and_the_effects_of_filament_cross-sectional_area_and_shape/9560336 Fluid (drag) forces acting on filaments in an air-flow are theoretically analysed, and equations to calculate them are derived. Drag forces acting on filaments are shown to vary with the filament cross-section, the position of the filaments across the nozzle, and the local air velocity. Since finer filaments have a smaller inertial resistance to fluid forces and have lower stiffness, yarns with finer filaments are shown to be more suitable for air-jet texturing. Theoretical modelling of a lament as it emerges from the nozzle shows that, for filaments with identical linear densities, those with cross sections having reduced bending and torsional stiffness, such as elhpt1c cross-sections, may be more suitable for air-jet texturing. 2015-11-10 13:34:16 untagged Mechanical Engineering not elsewhere classified Mechanical Engineering