A Study of Engineering Application of Pulsed Vortex Generator Jet

脉冲涡流发生器射流工程应用研究

基本信息

批准号：
11450080
负责人：
HONAMI Shinji
金额：
$ 3.84万
依托单位：
Science University of Tokyo
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (B).
财政年份：
1999
资助国家：
日本
起止时间：
1999 至 2000
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-11450080/
关键词：
Flow separation Reattaching flow Vortex generator jet Flow control Close loop control Pulsed jet Backward facing step flow 乱流境界層渦発生ジエットパルスジエット再付着過程能動制御マイクロセンサ

项目摘要

The general goal of the present study is to construct the closed loop control system of the reattachment process in a backward facing step flow by a row of the pulsed vortex generator jets. The step height is 40 mm. An expansion ratio of the test section height to the step height is 1.5. The step height Reynolds number is 2.7×10^4. The vortex generator jets are injected through a row of the 2 mm diameter injection holes. A micro wall flow sensor, which can detect near-wall flow reversal with a frequency response up to 500 Hz, measures time fraction of forward and backward flow. The reattachment line is almost parallel to the span-wise direction in the range of the hole pitch ratio of 10 to 20, although the discrete disturbance by jet injection is provided at the step. The reattachment length is decreased linearly up to the velocity ratio of 6. This means that the velocity ratio is one of the most effective manipulated variables in the control system of the reattachment process. The wall static pressure in the reattachment region is selected as the control feedback signal and the velocity ratio is used as the manipulated variable in the control system. The faster response of the system with the time constant of an order of 0.1 second is obtained. As a result, the present system can be employed in the engineering application as the effective control system for flow separation.

本研究的一般目标是通过一排脉冲涡流发电机喷气机以向后朝向的阶跃流动构建保留过程的闭环控制系统。步长为40毫米。测试部分高度与步长高度的膨胀比为1.5。台阶高度雷诺数为2.7×10^4。涡流发电机喷气机通过直径2 mm的注射孔的一排注入。一个微壁流传感器可以检测到近壁流，并以高达500 Hz的频率响应逆转，可测量向前和后流的时间分数。在孔音高比为10到20的范围内，保留线几乎平行于跨度方向，尽管在步骤中提供了喷射注射的离散灾难。固定长度线性降低至速度比为6。这意味着速度比是控制中最有效的操纵变量之一，在控制系统中，选择了保留区域中的壁静压区域中的壁静压，并且速度比被用作控制系统中的可操纵变量。获得了系统常数为0.1秒的时间常数的更快响应。结果，目前的系统可以在工程应用中用作流动分离的有效控制系统。