Active Control of Cascade Flutter in High-speed Flows by Acoustic Excitation

声激励对高速流中级联颤振的主动控制

• 批准号: 09450371
• 负责人: TOSHIMITSU Kazuhiko
• 金额: $ 8.7万
• 依托单位: KYUSHU UNIVERSITY
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B)
• 财政年份: 1997
• 资助国家: 日本
• 起止时间: 1997 至 1998
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-09450371/
• 关键词: Flutter; Cascade; PIV; Sound wave; Active control; Velocity vector; Unsteady flow

New subsonic wind tunnel facility for active control of cascade flutter and particle image velocimetry (PIV) has been constructed. Using the system and numerical simulations, the following results are obtained.Active Control :・ Flutter frequency and critical velocity of a flat plate blade (139.5*50*1mm) are estimated 118 Hz and 143 m/s respectively from the flutter experiment. On the other hand, they are found to be 165Hz and 123m/s from a finite element method calculation. This is because the FEM calculation neglects the effect of separated flow on the surface of a blade vibrating.・ The optimum suppression conditions of the flutter are calculated as follows ;- The center of actuator is located at the center of chord in stream-wise direction,- The amplitude and phase difference are 0.14 and -54 degrees respectively, which are normalized by bending oscillation.・ Amplitude of blade vibration is decreased by the acoustic excitation from two actuator diaphragms on tip-side wall when the diaphragms are operated based on bending vibration of the blade.PIV :・ Uniform flow velocity vectors are measured with the PIV system.・ Velocity vectors of steady flow around biconvex blade are measured with the PIV system.・ Turbulent flow around cylinder at Reynolds Number 1.0x10^5 is visualized with the NV system, in particular K・rm・n vortices behind cylinder are periodically observed.

已经建造了用于叶栅颤振和粒子图像测速（PIV）主动控制的新型亚音速风洞设施，利用该系统和数值模拟，获得了以下结果。主动控制：·平板叶片的颤振频率和临界速度（。 139.5*50*1mm）根据颤振实验分别估计为118Hz和143m/s，另一方面，发现它们分别为165Hz和165Hz。有限元法计算得出的 123m/s 这是因为 FEM 计算忽略了分离流对叶片振动的影响。 ・ 颤振的最佳抑制条件计算如下；- 执行器的中心位于在流向弦中心处，- 振幅和相位差分别为 0.14 和 -54 度，通过弯曲振动进行归一化。 ・ 叶片振动的振幅因声学激励而减小当膜片根据叶片的弯曲振动进行操作时，来自尖端侧壁上的两个执行器膜片。PIV：·使用 PIV 系统测量均匀流速矢量。·使用 PIV 测量双凸叶片周围的稳定流动的速度矢量・ 雷诺数为 1.0x10^5 的圆柱体周围的湍流通过 NV 系统可视化，特别是圆柱体后面的 K·rm·n 涡流周期性地出现观察到。

项目成果

Kazu Toshimitsu, Akihiro Yamagata, Kenichiro Nagai and Masanobu Namba: "Active Control of Low Frequency Cascade Flutter by Acoustic Exciation" Technology Reports of Kyushu University. 72-2. 115-121 (1999)

Kazu Toshimitsu、Akihiro Yamagata、Kenichiro Nagai 和 Masanobu Namba：《通过声激励主动控制低频级联颤振》九州大学技术报告。

利光和彦,他3名: "音波による低周波数翼列フラッタの能動的抑止" 九州大学工学集報. 72・2. 115-121 (1999)

Kazuhiko Toshimitsu等3人：“声波对低频叶片叶栅颤振的主动抑制”九州大学工学通报72・2（1999）。

利光和彦,他3名: "音波による低周波数翼フラッタの能動抑止" 九州大学工学集報. 72・2. 109-114 (1999)

Kazuhiko Toshimitsu 等 3 人：“利用声波主动抑制低频机翼颤振”九州大学工学通报 72・2（1999 年）。

利光和彦,他3名: "音波による低周波数翼フラッタの能動的抑止" 九州大学工学集報. 72・2. 109-114 (1999)

Kazuhiko Toshimitsu等3人：“声波对低频机翼颤动的主动抑制”九州大学工程通报72・2（1999）。

Kazu Toshimitsu, Takeshi Otsuka, Hiroko Maruo and Masanobu Namba: "Active Control of Low Frequency Blade Flutter by Acoustic Excitation" Technology Reports of Kyushu University. 72-2. 109-114 (1999)

Kazu Toshimitsu、Takeshi Otsuka、Hiroko Maruo、Masanobu Namba：《通过声激励主动控制低频叶片颤动》九州大学技术报告。