Simulating the helicopter-ship interface as an alternative to current methods of determining the safe operating envelopes

摘要

In the past decade, there has been a dramatic increase in the use of helicopters in conjunction with non-aviation ships by the U.S. Navy. Landing the helicopter on the ship in the presence of high winds and stormy seas can be a hazardous process. The safe operating envelopes are determined at sea by the Naval Air Test Center and is a slow laborious and expensive process. Moreover, there is a substantial backlog of about eleven helicopters and twenty ships that, at the present rate, cannot be cleared in this century. This has led to the suggestion that the problem might be solved by simulation, and it is with this suggestion that the present paper is concerned. (1) The airflow to the ship can be predicted sufficiently accurately, (2) A good basic ship motion prediction exists, but requires some further development and validation with real ships, (3) The ship airwake is almost unknown and previous attempts to analyze it were faulty, (4) Further work is required on turbulence modeling of helicopters, and (5) Before it is possible to determine the size of computer necessary for simulation it is necessary to determine the extent to which the mathematical model of the helicopter and the physical model of the complex fluid flowfield can be simplified, while still retaining the fidelity of the helicopter motion