Analytical and experimental investigation of drag on nets of fish cages

The effects of Reynolds number, net solidity and mesh pattern, and flow direction on the drag force on submerged nets of fish cages are studied. New formulae for the normal and tangential drag coefficients are proposed. The unknown constants in the formulae are determined from experimental data obtained in a towing tank for planar nets. It has been verified experimentally that the formulae are also applicable to cylindrical nets. Analytical formulae are derived for the total normal drag on planar and cylindrical nets with either square or square diamond mesh patterns.