The flow resistance of a clothed human body exposed to a strong wind (5-30m/s) was studied using a model system; a cylinder being loosely wrapped with a cloth. The drag coefficient of wind C
D increased with increase in the Reynolds number Re, when the cylinder covered by an endless cloth was exposed to wind. The value C
D tends to converge when Re approaches about 1.0×10
5. If the length of the cloth was less than twice the cylinder perimeter, the cloth shape in the wake of the cylinder was changed into beam-, ellipse-, or stable heart-, like shake, but C
D converged to the same value for almost all cases. The converged value, however, increased when the length of the cloth was near triple the perimeter of the cylinder. This value was found not to depend on the roughness of fabric surface and on the bending stiffness, but to depend only on the length of the sample cloth. The sample cloths of large air permeability and smooth surface showed almost similar C
D values for any sample length.
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