| Abstract
| - Exxon slot melt blowing dies consist of dual, rectangular, converging jets and are used in the industrial meltblowing process to attenuate molten polymer fibers. The air flow creates a drag force that accelerates thepolymer and rapidly reduces the fiber diameter. For previous experimental and computational fluid dynamicsstudies, the effect of the fiber on the air was assumed to be negligible. By including the fiber as a boundaryin the computational domain, this assumption was tested. A modified version of the Reynolds stress modelwas used to simulate the turbulent air flow field. It was determined that the centerline air velocity (locatedhalfway between the fibers) has an increased maximum due to the presence of the fiber. In addition, theturbulence in the flow field is dampened by the presence of the fiber. The jet spreading rate is higher halfwaybetween the fibers than at the center of the domain, where the fiber is located. The air flow around the fiberis nonuniform, leading to varied shear stress at different radial positions on the fiber edge. The temperatureof the air flow is related to the ratio of the polymer to air flow rate; as this ratio increases, the hot fiberreduces the cooling rate of the air.
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