streamline

streamline, path of a fluid flowing steadily and without appreciable turbulence. A body is said to be streamlined if its shape offers the least possible resistance to a current of air, water, or other fluid. The current that a streamlined body breaks simply reunites in its wake, as contrasted with the retarding eddies and turbulence created by the partial vacuum in the wake of a nonstreamlined body. The streamline design is typically a long ellipse tapering to a point in the direction of flow; it is illustrated in the cross section of an airplane wing and in the bodies of fishes and birds. Vehicles such as automobiles, aircraft, railroad cars, and boats are designed to provide maximum streamline.

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streamline

In fluid mechanics, the path of imaginary particles suspended in the fluid and carried along with it. In steady flow, the fluid is in motion but the streamlines are fixed. Where streamlines crowd together, the fluid speed is relatively high; where they open out, the fluid is relatively still. See also laminar flow, turbulent flow.

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A Macintosh tracing program from Adobe. It converts scanned or MacPaint images into PostScript files, which can be modified in Adobe Illustrator.