Air bubble barrier effect on neutrally buoyant objects

Laboratory experiments were carried out to study water kinematics induced by air bubble barriers, to evaluate their effectiveness in protecting water intakes from jellyfish attack. The experiments were performed in a recirculating wave flume under various water depths, unidirectional currents, air discharge rates and wave conditions. Neutrally buoyant floats were used to simulate jellyfish movement. It was found that an air bubble barrier alone is not adequate protection, and a net is recommended downstream of the barrier to stop jellyfish, moving towards the intakes.