Experimental and Numerical Analysis of a Micro Plasma Actuator for Active Flow Control in Turbomachinery

2014 ◽  
Author(s):  
Maria Grazia De Giorgi ◽  
Elisa Pescini ◽  
Fedele Marra ◽  
Antonio Ficarella
Keyword(s):  
Flow Control ◽  
Active Flow Control ◽  
Plasma Actuator ◽  
The Body ◽  
Plasma Actuators ◽  
Compressor Cascade ◽  
Barrier Discharge Plasma ◽  
Induced Flow ◽  
The One ◽  
Active Flow

Nowadays several active flow control systems, particularly dielectric barrier discharge plasma actuators, appear to be effective for the control of flow stream separation and to improve performance of turbomachinery. However these applications require high actuation strength, higher than the one generated by conventional macro plasma actuators. Research is actually improving the design of plasma actuator in order to enhance the flow control capability and reduce the power consumption. In this contest, this work concerns the implementation of a micro plasma actuator for the active control in a compressor cascade. For this aim, firstly the micro actuator was developed and an experimental characterization of the flow induced by the device was done. The induced flow field was studied by means of Particle Image Velocimetry and Laser Doppler Velocimetry. The dissipated power was also evaluated. Experimental results were used to validate a multi-physics numerical model for the prediction of the body forces induced by the plasma actuator. Finally, the obtained body force field was used for modeling the separation control by means of the micro plasma actuator in a highly-loaded subsonic compressor stator.

Simple frigate shape plasma flow control

2016 ◽  
Vol 230 (14) ◽  
pp. 2693-2699 ◽  
Author(s):  
R Bardera-Mora ◽  
A Conesa ◽  
I Lozano
Keyword(s):  
Flow Control ◽  
Active Flow Control ◽  
Plasma Actuators ◽  
Control Technique ◽  
Shape Model ◽  
Image Velocimetry ◽  
Barrier Discharge Plasma ◽  
Plasma Flow Control ◽  
Active Flow ◽  
Low Speed Wind Tunnel

This experimental investigation presents a new active flow control technique based on plasma actuators applied to a backward facing step whose structure is similar to that formed by the hangar and flight deck of small naval vessels. These experiments were carried out by testing a simple frigate shape model settled at 0° wind over deck in a low-speed wind tunnel. Two different configurations of dielectric barrier discharge plasma actuator have been used to modify the flow downstream of the step. Results obtained investigating the flow by particle image velocimetry prove the capacity of plasma actuators by reducing instabilities and turbulence over the simple frigate shape model.

Dielectric Barrier Discharge Plasma Actuators for Active Flow Control, Ice Formation Detection and Ice Accumulation Prevention

2020 ◽  
Author(s):  
F. F. Rodrigues ◽  
M. Abdollahzadeh ◽  
J. Pascoa
Keyword(s):  
Flow Control ◽  
Heat Dissipation ◽  
Active Flow Control ◽  
Capacitive Sensor ◽  
Plasma Actuator ◽  
Plasma Actuators ◽  
Ice Formation ◽  
Ice Accumulation ◽  
Barrier Discharge Plasma ◽  
And Control

Abstract An experimental investigation was conducted in order to understand the ability of plasma actuators to operate in three different modes: flow control, ice formation detection and ice accumulation prevention. When plasma actuators are operated with voltage levels, above the breakdown voltage, a plasma discharge surface is generated and with that, an ionic wind is produced. By using this phenomena, plasma actuators may be used to manipulate flow fields and control adjacent flows to the surface in which they are applied. However, a big part of the power applied to the device is dissipated as heat. Due to heat dissipation, the actuator surface temperature rises and the adjacent air is heated. Considering this, actuators may operate as ice prevention devices by heating the surface where they are applied and preventing the ice formation and accumulation. On the other hand, plasma actuators present a behavior similar to a capacitor and they may operate as a capacitive sensor. In the presence of water or ice on the top of the surface, the electric field changes and with that, several plasma actuator electrical features change as well. By monitoring that changes, the presence of water or ice on the top of the surface can be detected and the plasma actuator may be used as an ice sensor device. Therefore, in the present study a plasma actuator was experimentally tested operating in these three different operation modes and its feasibility to perform these different tasks is shown.

Structure optimization of the AC-SDBD plasma actuator under duty-cycle mode

2018 ◽  
Vol 32 (26) ◽  
pp. 1850315 ◽  
Author(s):  
Yuexiao Long ◽  
Huaxing Li ◽  
Xuanshi Meng ◽  
Jia Li ◽  
Zhengchao Xiang
Keyword(s):  
Flow Control ◽  
Duty Cycle ◽  
Aerodynamic Characteristics ◽  
Plasma Actuator ◽  
Force Balance ◽  
Plasma Actuators ◽  
Dielectric Barrier ◽  
Barrier Discharge Plasma ◽  
Control Authority ◽  
Induced Flow

Alternating current dielectric barrier discharge plasma actuators driven by steady and unsteady mode were experimentally optimized in a static atmosphere. The purpose of this optimization is to enhance the effective controllability of flow control. Electrical properties were evaluated using the measured voltage, current and power consumption data. The dielectric barrier with different materials was tested and the aerodynamic characteristics were identified by particle image velocimetry and electronic force balance. Meanwhile, the duty-cycle technique was applied to operate the actuator in unsteady mode. The dynamic characteristics of induced flow were analyzed by processing the results with the phase-locked method. The development of induced flow structure at different frequencies was compared. Results showed that the plasma actuator with 4 mm-thick Teflon dielectric barrier induced the maximum force and velocity of 75 mN/m and 5.6 m/s, respectively. The discharge frequency has little effect on the control authority at the kilohertz level. The dimensionless area of the induced flow is about [Formula: see text] under steady actuation. The phase-locked results confirm that the scale and strength of the induced vortex vary with the duty-cycle frequencies. The effectiveness of unsteady flow control can be explained as the promotion of the boundary layer and the mainstream.

Active Flow Control Techniques on a Stator Compressor Cascade: A Comparison Between Synthetic Jet and Plasma Actuators

2012 ◽  
Author(s):  
Maria Grazia De Giorgi ◽  
Stefania Traficante ◽  
Carla De Luca ◽  
Daniela Bello ◽  
Antonio Ficarella
Keyword(s):  
Boundary Layer ◽  
Flow Control ◽  
Active Flow Control ◽  
Pressure Ratio ◽  
Boundary Layer Separation ◽  
Synthetic Jet ◽  
Plasma Actuators ◽  
Compressor Cascade ◽  
Control Techniques ◽  
Active Flow

In this work a CFD analysis is applied to study the suppression of the boundary layer separation into a highly-loaded subsonic compressor stator cascade, by different active flow control techniques. Active flow control techniques have the potential to delay separation and to increase the pressure ratio. In particular three different techniques have been applied: the actuation by steady jet, by zero net mass flux Synthetic Jet (SJA) and by plasma actuator. Several works have investigated the use of synthetic jet and plasma actuators on the airfoil, but only few studies have compared the effect of these devices. Concerning the synthetic jet actuator, a suction/blowing type boundary condition is used, imposing a prescribed sinusoidal velocity depending on velocity amplitude, jet frequency and jet angle of ejection with respect to the wall. Concerning the plasma actuation, the effect is modeled into numerical flow solvers by adding the paraelectric force that represents the plasma force into the momentum equation. The plasma, generated by Dielectric Barrier Discharge, acts as a momentum source to the boundary layer allowing it to remain attached throughout a larger portion of the airfoil. The time-averaged body force component, acting on the fluid, depends on the frequency and on the applied voltage, the charge density, the electrical field and the dimensional properties of the actuator, like width of the electrodes and gap between the electrodes. Using this numerical model, the effect of plasma actuators to suppress the flow separation over the blade has been investigated, increasing the turbo-machinery performance too. Finally, the comparison between the different actuation devices shows that, reducing the secondary flow structures, each actuation technique beneficially affects the performance of the stator compressor cascade, even if in the steady jet the costs are relevant.

Comparative Evaluation of Dielectric Materials for Plasma Actuators Active Flow Control and Heat Transfer Applications

2021 ◽  
Author(s):  
F. F. Rodrigues ◽  
J. Nunes-Pereira ◽  
M. Abdollahzadeh ◽  
J. Pascoa ◽  
S. Lanceros-Mendez
Keyword(s):  
Heat Transfer ◽  
Flow Control ◽  
Dielectric Layer ◽  
Active Flow Control ◽  
Thermal Power ◽  
Dielectric Materials ◽  
Plasma Actuators ◽  
Dbd Plasma ◽  
Control Applications ◽  
Active Flow

Abstract Dielectric Barrier Discharge (DBD) plasma actuators are simple devices with great potential for active flow control applications. Further, it has been recently proven their ability for applications in the area of heat transfer, such as film cooling of turbine blades or ice removal. The dielectric material used in the fabrication of these devices is essential in determining the device performance. However, the variety of dielectric materials studied in the literature is very limited and the majority of the authors only use Kapton, Teflon, Macor ceramic or poly(methyl methacrylate) (PMMA). Furthermore, several authors reported difficulties in the durability of the dielectric layer when the actuators operate at high voltage and frequency. Also, it has been reported that, after long operation time, the dielectric layer suffers degradation due to its exposure to plasma discharge, degradation that may lead to the failure of the device. Considering the need of durable and robust actuators, as well as the need of higher flow control efficiencies, it is highly important to develop new dielectric materials which may be used for plasma actuator fabrication. In this context, the present study reports on the experimental testing of dielectric materials which can be used for DBD plasma actuators fabrication. Plasma actuators fabricated of poly(vinylidene fluoride) (PVDF) and polystyrene (PS) have been fabricated and evaluated. Although these dielectric materials are not commonly used as dielectric layer of plasma actuators, their interesting electrical and dielectric properties and the possibility of being used as sensors, indicate their suitability as potential alternatives to the standard used materials. The plasma actuators produced with these nonstandard dielectric materials were analyzed in terms of electrical characteristics, generated flow velocity and mechanical efficiency, and the obtained results were compared with a standard actuator made of Kapton. An innovative calorimetric method was implemented in order to estimate the thermal power transferred by these devices to an adjacent flow. These results allowed to discuss the ability of these new dielectric materials not only for flow control applications but also for heat transfer applications.

Experimental Investigations on the Efficiency of Active Flow Control in a Compressor Cascade With Periodic Non-Steady Outflow Conditions

2017 ◽  
Author(s):  
Marcel Staats ◽  
Wolfgang Nitsche
Keyword(s):  
Flow Field ◽  
Flow Control ◽  
Flow Separation ◽  
Active Flow Control ◽  
Experimental Investigations ◽  
Compressor Cascade ◽  
Steady Regime ◽  
Stator Blade ◽  
Active Flow ◽  
The Impact

We present results of experiments on a periodically unsteady compressor stator flow of the type which would be expected in consequence of pulsed combustion. A Reynolds number of Re = 600000 was used for the investigations. The experiments were conducted on the two-dimensional low-speed compressor testing facility in Berlin. A choking device downstream the trailing edges induced a periodic non-steady outflow condition to each stator vane which simulated the impact of a pressure gaining combuster downstream from the last stator. The Strouhal number of the periodic disturbance was Sr = 0.03 w.r.t. the stator chord length. Due to the periodic non-steady outflow condition, the flow-field suffers from periodic flow separation phenomena, which were managed by means of active flow control. In our case, active control of the corner separation was applied using fluidic actuators based on the principle of fluidic amplification. The flow separation on the centre region of the stator blade was suppressed by means of a fluidic blade actuator leading to an overall time-averaged loss reduction of 11.5%, increasing the static pressure recovery by 6.8% while operating in the non-steady regime. Pressure measurements on the stator blade and the wake as well as PIV data proved the beneficial effect of the active flow control application to the flow field and the improvement of the compressor characteristics. The actuation efficiency was evaluated by two figures of merit introduced in this contribution.

Sign in / Sign up

Export Citation Format

Share Document