Research into ship design for aircraft operations

在海上将直升机降落在船上是直升机飞行员可能面临的最苛刻和最危险的任务之一。能见度下降和有限的着陆区，船舶运动和低速飞机操纵品质差，加上一直存在的，但不可见的，船舶空气尾流，它可以非常显着地干扰着陆过程中的最后关键阶段。对于来自船首方向的风，登陆甲板上的气流类似于三维后向台阶后面的气流。当直升机旋翼进入与机库顶部和侧面分离的自由剪切层时，局部气流冲击角以及旋翼推力和力矩发生显著变化。为了安全地降落在移动甲板上，飞行员必须通过控制来施加高工作负荷，以克服不稳定的力矩和力。本提案的目的是推进这一领域的研究，使申请人能够代表英国参加北约探索小组，该小组的作用是指导未来对直升机着陆甲板上的气流不会不必要地限制作战包线的船舶设计的研究，并向飞行员提出过于危险的任务。最近由申请人进行的epsrc资助的研究表明，修改船舶以改善登陆甲板上的气流是可能的。然而，检查气流本身并据此预测对直升机的可能影响可能会产生误导。因此，申请人已经开发了一种虚拟工程技术，其中，通过计算流体动力学计算船舶上的不稳定复杂气流，并与飞行建模软件和有人驾驶的运动基础飞行模拟器一起使用，以有效地将直升机“飞行”到船舶上，以评估由船舶空气动力学引起的困难。北约小组的目的是审查这一领域目前的研究，并以此为基础，为今后的研究提供信息。由于申请人是英国在这一领域的主要研究人员，他必须利用自己的经验为探索小组的工作提供信息，并告知北约国家希望发展的未来研究方向。

Landing a helicopter on a ship at sea is one of the most demanding and hazardous tasks that a helicopter pilot can face. Degraded visibility and a confined landing area, ship motion and poor low-speed aircraft handling qualities are compounded by the ever present, but invisible, ship airwake, which can very significantly disturb the landing process in the final critical phases. For winds coming from the direction of the bow, the flow over the landing deck is similar to that behind a three-dimensional backward facing step. As the helicopter rotor moves into the free shear layers which separate from the top and sides of the hangar, local flow impingement angles and hence the rotor thrust and moments vary significantly. In order to land safely onto the moving deck, the pilot has to exert high workload through the controls to overcome the unsteady moments and forces. The purpose of this proposal is to advance research in this area by enabling the applicant to represent the UK on a NATO Exploratory Team whose role will be to direct future research into the design of ships for which the airflow over the helicopter landing deck does not unnecessarily restrict the operational envelope, and present the pilot with too dangerous a task. Recent epsrc-funded research carried out by the applicant has shown that it is possible to modify a ship to improve the airflow over the landing deck. However, examining the airflow itself and predicting from that the likely effect on the helicopter can be misleading. The applicant has therefore developed a virtual engineering technique in which the unsteady complex airflow over the ship is calculated by Computational Fluid Dynamics and used with flight modelling software and a piloted motion base flight simulator to effectively 'fly' a helicopter onto the ship to evaluate the difficulties arising from the ship aerodynamics. The purpose of the NATO group is to review the current research in this area and use this to inform future research. As the applicant is the key researcher in the UK in this area, it is important that he uses his experience to inform the work of the Exploratory Team, and that he is informed of the future research direction that NATO countries wish to develop.