Research into ship design for aircraft operations

直升机在海上降落在船上是直升机飞行员面临的最苛刻和最危险的任务之一。能见度降低、着陆区受限、船舶运动和低速飞机操纵质量差，再加上一直存在但看不见的船舶尾流，在最后关键阶段可能会非常显著地干扰着陆过程。对于来自船头方向的风，在起落架甲板上的流动类似于三维后向台阶后面的流动。当直升机旋翼进入与机库顶部和两侧分离的自由剪切层时，局部气流碰撞角以及旋翼推力和力矩变化很大。为了安全地降落在移动甲板上，飞行员必须通过操纵器施加高工作量来克服不稳定的力矩和力。这项提议的目的是推进这一领域的研究，使申请者能够代表英国加入北约的一个探索小组，该小组的角色将是指导未来对直升机起落台上方的气流不会不必要地限制操作范围的船只设计的研究，并向飞行员提出一项过于危险的任务。由EPSRC资助的申请人最近进行的研究表明，有可能改装一艘船来改善起落架上方的气流。然而，检查气流本身并由此预测可能对直升机的影响可能具有误导性。因此，申请人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方的非稳定复杂气流，并与飞行建模软件和有人驾驶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上，以评估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的当前研究，并利用这一点为未来的研究提供信息。由于申请者是英国在这一领域的关键研究人员，重要的是他要利用自己的经验为探索团队的工作提供信息，并告知他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.