Hydrodynamic resistance of pipes and nets fouled with the acorn barnacle

When the members of a crawl, the pipes, ropes and nets are fouled with acron barnacles in the sea, the hydrodynamic resistance increases and the crawl is broken under condition where the seas are rough.In this paper, laboratory tests were conducted to determine the hydrodynamic resistance of pipes and plane nets which were fouled with the acron barnacle.The drag coefficient (CD) of barnacle covered pipes placed at a right angle to the stream was 1.1 where the range of the Reynolds numbers were between 2, 000 to 40, 000. This result suggested that the boundary layer flow separated at the same point because the surface of the pipe was very rough.The drag coefficient (CD) of barnacle fouled plane nets placed at a right angle to the stream depended on the ratio of the solid area to the total area of the net ( ?? ) rather than on the Reynolds number. That is where CD=0.85/(1- ?? )2 at ??