基于定常/非定常质量射流技术的前飞旋翼桨尖涡流场及噪声控制研究

Due to the BVI (Blade-Vortex Interaction) phenomenon of helicopter rotor occurred in forward flight, the aerodynamic performance and noise level of a rotor are significantly influenced. In order to solve the interaction problems from fountainhead, steady and unsteady TAMI (Tip Air Mass Injection) technology will be adopted to control the vortex strength, such that the strength of BVI can be decreased, and the noise level of a rotor can be reduced eventually. This project is established to investigate problems as follows: (1) A high-resolution method for the simulation of rotor vortex with TAMI control in forward flight; (2) Formation and evolution mechanism, as well as the variation law, of rotor tip vortex in forward flight; (3) The control laws of steady and unsteady TAMI for rotor tip vortex in forward flight; (4) An efficient method for controlling aerodynamic noise of a forward-flight rotor. Previous researches are focused on the rotor tip vortex control in hover, while the BVI and noise characteristics of helicopter rotor have not been really calculated. Therefore, researches in this project are more challenging, but are of better innovativeness and practical meaning.

前飞状态下直升机旋翼会发生桨-涡干扰现象，对旋翼的气动性能和噪声特性产生严重的影响。为了从源头上解决该问题，本项目拟采用定常/非定常质量射流技术对旋翼桨尖涡进行控制，从而减弱旋翼桨-涡干扰的强度，最终降低前飞状态下的旋翼气动噪声。拟通过本项目的研究对以下问题进行探索：（1）前飞旋翼桨尖涡及其质量射流控制的高精度模拟方法；（2）前飞状态旋翼桨尖涡的生成、演化机理和非定常演变特性；（3）前飞旋翼桨尖涡的定常/非定常质量射流控制规律；（4）前飞旋翼气动噪声的有效控制方法。先前的大部分研究主要针对悬停状态桨尖涡的涡核强度控制，并未真正涉及旋翼桨-涡干扰和噪声特性的控制和计算，因此，本项目的研究更具挑战性，但也更具创新性和实际意义。

为了解决前飞状态旋翼桨-涡干扰带来的气动干扰和噪声等问题，本项目通过定常/非定常质量射流控制方法对前飞非定常旋翼涡进行控制，通过主动流动控制方式抑制旋翼桨尖涡涡核强度，从而进一步减弱旋翼气动噪声。本项目的主要研究内容有：（1）适用于前飞旋翼桨尖涡及其质量射流控制模拟的高精度模拟方法；（2）前飞状态旋翼非定常桨尖涡的生成、演化机理和非定常演变特性研究；（3）前飞旋翼桨尖涡的定常/非定常质量射流控制研究；（4）前飞旋翼气动噪声的定常/非定常控制方法研究。参数化计算结果和分析表明：（1）建立的高精度数值模拟器能够精确地对前飞旋翼桨尖涡进行模拟，计算得到了前飞旋翼桨尖涡涡核特征的非定常演变规律；（2）在旋翼桨尖涡涡核强度减弱方面非定常质量射流控制优于定常质量射流控制，本项目创新提出的“选择性方波”控制策略能够最大程度地减弱旋前飞翼桨尖涡的涡核强度；（3）旋翼桨盘前侧的桨尖涡涡核强度难以通过定常/非定常质量射流控制方式得到减弱；（4）定常/非定常质量射流均能一定程度减弱旋翼气动噪声，但效果还不够理想，本项目提出了进一步的工作展望以及建议，以期获得更好的旋翼噪声控制效果。