Flow Control over a Cylinder Using Duty-Cycle Plasma Actuation

2020 ◽  
Author(s):  
Weiwei Hui ◽  
Huaxing li ◽  
Yin Shiqing ◽  
Afaq A. Abbasi ◽  
Xuanshi Meng
2017 ◽  
Vol 45 (4) ◽  
pp. 672-682 ◽  
Author(s):  
Feng Li ◽  
Chao Gao ◽  
Borui Zheng ◽  
Yushuai Wang ◽  
Zhe Lv ◽  
...  

2012 ◽  
Vol 14 (1) ◽  
pp. 58-63 ◽  
Author(s):  
Borui Zheng ◽  
Chao Gao ◽  
Yibin Li ◽  
Feng Liu ◽  
Shijun Luo
Keyword(s):  

2019 ◽  
Vol 36 (3) ◽  
pp. 361-372
Author(s):  
Vedulla Manoj Kumar ◽  
Chin-Cheng Wang

ABSTRACTThe concept of the fixed wing Micro Air Vehicles (MAVs) has received increasing interest over the past few decades, with the principal aim of carrying out the surveillance missions. The design of the flapping wing MAVs still is in infancy stage. On the other hand, there has been increasing interest over the flow control using plasma actuators in worldwide. The aim of this research is to study the flow control of a flapping airfoil with and without plasma actuation in OpenFOAM. The OpenFOAM CFD platform has been used to develop our own plasma solver. For the plasma induced turbulence in the flow regime, k-ε turbulence model was adopted to address the interaction between plasma and fluid flows. For the plasma-fluid interaction, we use reduced-order modelling to solve the plasma induced electric force. A two dimensional NACA0012 flapping airfoil without plasma actuation study has been benchmarked with previous published literature. We have not only focused on the active flow control but also analyzed the important parameter reduced frequency at different values, those are 0.1, 0.05 and 0.025. Reduced frequency (κ) is very important parameter of an airfoil in the unsteady motion. Our major contribution is testing the several reduced frequencies with the plasma actuation. The positive and beneficial effects of the plasma actuator for all cases have been observed. From the observed results, the flapping with plasma actuation at reduced frequency of 0.1 showed the 14.285 percent lift improvement and the 16.19 percent drag reduction than the flapping without plasma actuation at the respective dynamic stall angles. The maximum lift coefficient is increased with the increase in reduced frequency. In overall, plasma actuators are effective in the flow control of a flapping airfoil. In future, the combination of the flapping with plasma actuators will be a promising application to boast the maneuverability of MAVs.


Energies ◽  
2019 ◽  
Vol 12 (20) ◽  
pp. 4011 ◽  
Author(s):  
Zhonglin Lin ◽  
Qingyan Wei ◽  
Runmin Ji ◽  
Xianghua Huang ◽  
Yuan Yuan ◽  
...  

In this paper, a fuzzy logic based volume flow control method is proposed to precisely control the force of a pneumatic actuator in an electro-pneumatic system including four on-off valves. The volume flow feature, which is the relationship between the duty cycle of the pulse width modulation (PWM) period, pressure difference, and volume flow of an on-off valve, is based on the experimental data measured by a high-precision volume flow meter. Through experimental data analysis, the maximum and minimum duty cycles are acquired. A new volume flow control method is introduced for the pneumatic system. In this method, the raw measured data are innovatively processed by a segmented, polynomial fitting method, and a newly designed procedure for calculating the duty cycle is adopted. This procedure makes it possible to combine the original data with fuzzy logic control (FLC). Additionally, the method allows us to accurately control the minimum and maximum opening pulse width of the valve. Several experiments are performed based on the experimental data, instead of the traditional theoretical models. Only 0.141 N (1.41%) overshoot and 0.03 N (0.03%) steady-state error are observed in the step response experiment, and 0.123 N average error is found while tracking the sine wave reference.


Author(s):  
Guo-Zheng Song ◽  
Hua Liang ◽  
Wei Biao ◽  
Su Zhi ◽  
Xie Like ◽  
...  

As a new kind of active flow control technology, plasma flow control has a bright future, for its simple structure, fast response, and wide frequency band. The wind tunnel and flight tests were conducted with microsecond dielectric barrier discharge on a glider. For the tests, the microsecond pulse power supply and remote control system were designed and built. In the wind tunnel test, the flow separation on the glider wing surface can be controlled effectively, and static pressure at the leading edge pressure is decreases by 177%. The flow control effects under different pulse frequencies are compared, and the optimal pulse frequency for actuation is found to be 100 Hz. A significant hysteresis effect was observed with microsecond dielectric barrier discharge at small angle of attack (α ≤ 18°), which means the flow control effect can last more than 300 s after turning off the plasma actuation. In the flight test, the maximum roll angle decreases by 7.0°, and the maximum aileron deflection angle decreases by 9.4° with plasma actuation at both sides of the wing, which means the glider becomes more stable with microsecond dielectric barrier discharge. With unilateral actuation, the rolling moment generated by the plasma actuation is larger than that produced by the ailerons with the angle of attack within 12.94° ≤ α ≤ 29.77°, which shows strong rolling control ability of microsecond dielectric barrier discharge. The wind tunnel and flight tests results verified the flow control effect of microsecond dielectric barrier discharge, and paved the way for the plasma flow control technology to practical applications.


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