Academic literature on the topic 'Continous blowing'

Almost a half century ago development efforts were initiated by very different entities, in widely different locations, to demonstrate one step processes to convert polymer to web: • Major fiber producers (DuPont, Freudenberg, Monsanto) began work on converting polymer (PE, PET, Nylon) into continuous “cold drawn” filaments and integrating the conversion of these filaments into a random-laid bonded nonwoven fabric. • An oil company (Exxon), building on the earlier work (1950's) of the Naval Research Labs to produce fine fibers, began work on converting their recently commercialized PP polymer into discontinuous, or continuous, “hot drawn” filaments and integrating these filaments into a random-laid self bonded nonwoven web having average fiber sizes 2–5 microns (fine fibered webs) to 100+ fibers (coarse fibered webs). As a result of these early development efforts, three different, but related melt spinning nonwoven processes have achieved significant commercial importance, with tremendous benefits to consumers worldwide: • Spunbond process • Melt blowing process • Flash spinning process This presentation will summarize the development of the melt blowing process from conceptualization to current state-of-the-art. Important product, process and equipment developments are detailed in the 50 year growth of the melt blowing process from a laboratory concept to a 125 million pound a year U.S. and Canadian commercial business and substantial additional worldwide consumption. Today, spunbond and melt blown processes are used for approximately 54% of the total 18.6 million square yards U.S. nonwoven market.

AbstractAn experimental investigation was conducted to study the effect of synthetic jet (oscillatory, zero net mass flow jet) blowing near the wing tip, as a means of diffusing the trailing vortex. Velocity measurements were taken, using a Particle Image Velocimetry system, around the tip and in the near wake of a rectangular wing, which was equipped with several blowing slots. The effect of the synthetic jet was compared to that of a continuous jet blowing from the same configurations. The results show that the use of synthetic jet blowing is generally beneficial in diffusing the trailing vortex and comparable to the use of continuous jet. The effect was more pronounced for the highest blowing coefficient used. The driving frequency of the jet did not generally prove to be a significant parameter. Finally, the instantaneous and the phase-locked velocity measurements helped explain the different mechanisms employed by the continuous and synthetic jets in diffusing the trailing vortex.