Start-up flow of viscoelastic fluid in the two-dimensional channel with a four to one tapered contraction is numerically analyzed by using the finite element method, and the transient behavior of viscoelastic flow is discussed. The Leonov model is applied to describe the rheological behavior of the fluid.
In the flow through the tapered contraction, the velocity gradient in the flow direction, ∂u/∂x, along the center line becomes smaller than that in the flow through an abrupt contraction, and the maximum of the normal stress difference, τ_xx, τ_yy, in the tapered contraction channel is also smaller than that of the flow in the abrupt contraction channel.
The peak position of ∂u/∂x moves with time, and this phenomenon has not been observed in the numerical simulation of the start-up flow in the channel with an abrupt contraction.

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This investigation was conducted to put to practical application coiled sheet shaving method. To prevent the fiber from sticking to each other during shaving, a new method using hot water soluble resin coated coil was proposed. Production equipments for the new method which can be applied industrially were developed and their basic performances were examined. It was confirmed that fiber sticking could be prevented with coating thickness of 1220μm and various kinds of metal fibers as stainless steel, nickel, titanium could be produced efficiently by the developed equipments Further, non-woven fabric production equipments was developed suitable for these fibers eliminating problems such as breaking of fibers with the current non-woven fabric production methods.

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Thickness irregularity (“Mura”) is an important factor in the quality inspection of nonwoven fabric, and in the factory, it is evaluated by human sight-cheek. Human sight-check, however, involves some problems in objectivity and reliability. It is therefore desirable to develop an automatic inspection machine.
In this report, the relation between the value of human sight check and statistics of image processing for nonwoven fabric was investigated and the regression equation of this relation was obtained.. The equation had a high multiple correlation coefficient of 0.94 and should be useful in developing an automatic inspection machine.

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