Experimental investigation of airflow over the helicopter platform of a polar icebreaker

The airwake over the helicopter platform of a Canadian Coast Guard (CCG) polar icebreaker was studied experimentally. By application of high-speed particle image velocimetry (PIV) on a 1:522 scaled model of the polar icebreaker, quantitative flow field data were obtained in several vertical and horizontal planes. The investigation compared the effects of two types of inflow conditions: (i) a uniform flow and (ii) a simulated atmospheric boundary layer (ABL) on the flow structure over the helicopter platform of the ship. The incidence angle (α) between the oncoming flow and the orientation of the ship varied between 0° and 330° with the increment of 30°. The unsteadiness of the flow and the turbulent fluctuations were quantified by calculating the components of the Reynolds stress tensor and the turbulence intensity. Higher maximum values of the turbulence intensity were observed in the case of the simulated ABL. For both inflow conditions, the incidence angle of 300° corresponded to the highest turbulence levels over the helicopter platform.