Abstract:
When a ship is navigating on the sea, it will undergo six-degree-of-freedom motions in space, which can have adverse effects on the aerodynamic characteristics and handling performance of a helicopter during landing. To study the aerodynamic characteristics of helicopter landing in the ship-aircraft coupled flow field, a measurement and control system for wind tunnel experiments simulating ship-aircraft coupling characteristics was independently designed. This system can achieve the simulation of a ship's six-degree-of-freedom motion, the monitoring and acquisition of the load and rotational speed of a helicopter model, and the synchronous acquisition of the ship's attitude and the helicopter's load. Through experiments, data on the loads of the helicopter model and the ship's attitude under different working conditions were obtained. The results show that when the ship pitches and oscillates, due to the periodic change in the distance between the propeller disk and the ship's deck and the ground effect, the lift of the rotor changes dynamically at the same frequency and there is a phase lag. The results indicate that this measurement and control system has successfully achieved the synchronous measurement of the aerodynamic load of the helicopter during landing and the ship's attitude when the ship is in motion. The obtained data conforms to the laws of helicopter aerodynamics and fully meets the experimental requirements, providing crucial technical support and data basis for the research on the aerodynamic characteristics of helicopters in the complex ship-aircraft coupled flow field.