Application Of Dielectric Barrier Discharge Research Articles

Conversions and selectivities in cold plasma partial oxidation of methane

AbstractIn the present work, the application of dielectric barrier discharge (DBD) cold plasma technology for the partial oxidation of methane was systematically studied. Conversion of the reactants and selectivities were measured using an elaborate product analysis from a recent work by Müller et al. varying the reactant ratio in the feed, the mole fraction of the inert carrier gas argon in the feed, and the specific energy input at operating conditions close to ambient. The results from 20 new experiments carried out in the present work complement 23 previous experiments and provide an unprecedented comprehensive quantitative data set. This extends the available knowledge of partial oxidation of methane in DBD cold plasma considerably and is useful for testing mechanistic models.

Optimisation of plasma-activated water: Plasma DBD technology and application in recirculating aquaculture system for Nile tilapia larval culture

Plasma-activated water (PAW) is a useful tool for producing pathogen-free seed fish. This study aimed to apply dielectric barrier discharge (DBD) plasma to reduce the microbial population in the water of a recirculating aquaculture system (RAS) for Nile tilapia larval culture. Initially, a PAW system prototype was developed and found to effectively reduce bacterial populations in both stagnant and circulating water. Additionally, a slight increase in water temperature was observed in the circulating water. Subsequently, the optimisation of PAW conditions in the circulating water was performed. The PAW system, with a copper anode distance of 2 cm and a 1 cm distance between the copper tip and the water surface, combined with a non-spaced cathode pad, exhibited the highest bactericidal effect. Using the optimised PAW conditions, for Experiment I, Nile tilapia larval culture was established in the RAS, supplemented with a bacterial suspension (Bacillus subtilis, Streptococcus agalactiae and Aeromonas hydrophila) to assess the bactericidal effects. Three treatments were applied: 1) control (no PAW or antibiotics), 2) PAW, and 3) antibiotic treatment for Nile tilapia larvae cultured in the RAS system for 672 h. The results demonstrated that both PAW and antibiotic treatments significantly reduced the bacterial populations in the water in relation to the control (P < 0.05). Moreover, a substantial reduction in bacterial population was observed in the whole body of the fingerlings in both the PAW and antibiotic groups in relation to the control fingerlings (P < 0.05). In Experiment II, Nile tilapia larval culture in the RAS was conducted under three different conditions: 1) control (no PAW or antibiotic), 2) PAW, and 3) antibiotic treatment, to evaluate the antimicrobial effects of PAW on waterborne bacterial populations for 672 h. Similar to Experiment I, both antibiotic and plasma treatments significantly reduced the bacterial populations in the water and whole-body fingerlings in relation to the control (P < 0.05). Notably, the growth performance and whole-body composition (moisture, crude protein, crude fat, and ash) of the fingerling fish appeared comparable among the experimental groups (P > 0.05), suggesting that PAW had no detrimental effects on long-term fish culture. Therefore, PAW can be employed to effectively reduce bacterial populations in water, thus minimising bacteria-related issues in fish without adverse impacts on fish growth.

Hydrophilic surface modification of polypropylene by AC-DBD and NS-DBD

Dielectric barrier discharge (DBD) is a method to modify material surfaces by creating low-temperature plasma at atmospheric pressure. However, in comparison to low-pressure discharge, atmospheric DBD has the drawback of uneven surface treatment due to the ease of forming filamentary channels. This limitation hinders the widespread application of DBD technology in material surface modification. In this study, the surface of polypropylene (PP) was treated using high frequency alternating current (AC) and nanosecond (NS) pulsed argon DBDs to improve surface hydrophilicity. The changes of the PP surface hydrophilicity and the treatment uniformity were characterized by water contact angle (WCA) measurement. The relationships between the DBD characteristics, the treatment effect and the treatment uniformity of the PP surface were investigated using electrical and optical diagnostic techniques. The PP material surfaces before and after plasma treatments were evaluated by the physical morphology and chemical composition measurements to examine the influence of DBD on the treatment effect and uniformity on the PP material surface. The findings show that the modification by AC-DBD reduces the WCA of PP material surface by 40°∼50° and exhibits a variance of 1.77, indicating an improvement in hydrophilicity to some extent. Furthermore, the modification by NS-DBD further decreases the WCA of PP material surface, reducing the variance to 1.14. Compared with AC-DBD, NS-DBD has a better uniformity, a higher concentration of active particles in plasma, a greater surface roughness of PP material after treatment, a better hydrophilicity and a more uniform effect with less energy consumption. The results are meaningful to improve the application of DBD in material surface modification and optimize the power source election and operation parameters.

Characteristics of high-repetition-rate bipolar pulse DBD under various electrical conditions in atmospheric-pressure air

Numerous studies have been conducted on pulse dielectric barrier discharge (DBD) because it can produce powerful discharges uniformly at atmospheric pressure with a fast rise time. Although much research has been conducted on pulse DBD below 10 kHz, relatively little has been conducted on pulse DBD at high pulse repetition rates (PRRs). Therefore, in this study, the ozone generation and discharge characteristics of bipolar pulse DBD in atmospheric-pressure air at a high PRR of 10 kHz or above were investigated. According to the results of this study, with the exception of electron temperature, most discharge characteristics need for practical applications—like transfer charge, electron density, and discharge uniformity—improved as the voltage and duty ratio increased at high PRR. On the contrary, increasing the PRR exhibited trade-off features like low electron temperature, low discharge uniformity, and a high number of discharges per unit time. Ozone generation demonstrated good results at high voltage, appropriate PRR, and low duty ratio, but applying suitable electrical conditions is crucial considering ozone generation speed and power consumption. The findings of this study will be very beneficial for high-PRR pulse DBD applications that require quick and effective processing. Additionally, they will be useful for researching the characteristics of pulse DBD at high PRR.

Competitive formation of NO, NO2, and O3 in an air-flowing plasma reactor: A central role of the flow rate

Beyond ozone (O3) generation, diverse applications of dielectric barrier discharge (DBD) have been developed. When using ambient air, one of the longstanding challenges of DBD reactors has been the selective production of nitric oxide (NO), nitrogen dioxide (NO2), and O3. In this work, we report the competitive formation of NO, NO2, and O3 in an air-flowing surface DBD reactor. The temporal evolution of each chemical species was obtained by using in situ optical absorption spectroscopy. The possibility to select the plasma-chemistry mode (i.e., NO–, NO2–, or O3-dominant conditions) by adjusting the gas flow rate of the reactor was demonstrated with constant temperature and input power. As the flow rate increased from 260 to 1380 standard cubic centimeters per minute, the dominant chemical species changed from NO to NO2 [the achieved purity of NO2/(NO + NO2 + O3) was 99%]. With even higher flow rates, O3 appeared and dominated in the reactor [O3/(NO + NO2 + O3) was nearly 100%]. The experimental results were compared with zero-dimensional modeling, and the reactions involving NO, NO2, and O3 were analyzed in depth. Our findings will provide great guidance for future studies and for plasma applications of DBD reactors.

Analysis and Experimental Validation of an Integrated Current-Source Power Supply With High Power Factor for DBD Applications

An integrated current-source high-frequency pulse excitation power supply with high power factor (PF), low total harmonic distortion (THD) of the input current, and high efficiency for dielectric barrier discharge (DBD) loads is proposed in this article. The proposed power supply consists of a current source unit and a bipolar pulse excitation voltage generation unit. The current source unit is used to generate a current source for the excitation voltage generation unit and achieve a high PF and a low current harmonic distortion in the ac side of the proposed power supply. By planning the modes of the excitation voltage generation unit, not only a bipolar pulse excitation voltage with high rising and falling rates on the DBD loads is generated, but also the soft-switching of all power switches is achieved. The experimental results show that not only a unity PF ( <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$&gt;$</tex-math> </inline-formula> 0.99) and a low THD ( <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$&lt;$</tex-math> </inline-formula> 10%) are achieved, but also a bipolar high-frequency (hundreds of kilohertz) pulse excitation voltage with high average rising and falling rates (7.227 <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\times$</tex-math> </inline-formula> 109 V/s) for a DBD excimer lamp is generated. Finally, in comparison with different power supplies, the proposed power supply can not only fully take advantage of the potential of the DBD excimer lamp but also has many advantages of high efficiency (92%), integrated structure, and simple driver.

Dry reforming in a dielectric barrier discharge reactor with non-uniform discharge gap: Effects of metal rings on the discharge behavior and performance

The application of dielectric barrier discharge (DBD) plasma reactors is promising in various environmental and energy processes, but is limited by their low energy yield. In this study, we put a number of stainless steel rings over the inner electrode rod of the DBD reactor to change the local discharge gap and electric field, and we studied the dry reforming performance. At 50 W supplied power, the metal rings mostly have a negative impact on the performance, which we attribute to the non-uniform spatial distribution of the discharges caused by the rings. However, at 30 W supplied power, the energy yield is higher than at 50 W and the placement of the rings improves the performance of the reactor. More rings and with a larger cross-sectional diameter can further improve the performance. The reactor with 20 rings with a 3.2 mm cross-sectional diameter exhibits the best performance in this study. Compared to the reactor without rings, it increases the CO2 conversion from 7% to 16 %, the CH4 conversion from 12% to 23%, and the energy yield from 0.05 mmol/kJ supplied power to 0.1 mmol/kJ (0.19 mmol/kJ if calculated from the plasma power), respectively. The presence of the rings increases the local electric field, the displaced charge and the discharge fraction, and also makes the discharge more stable and with more uniform intensity. It also slightly improves the selectivity to syngas. The performance improvement observed by placing stainless steel rings in this study may also be applicable to other plasma-based processes.

Review of Ceramic Composites in Aeronautics and Aerospace: A Multifunctional Approach for TPS, TBC and DBD Applications

The quest for increased performance in the aeronautical and aerospace industries has provided the driving force and motivation for the research, investigation, and development of advanced ceramics. Special emphasis is therefore attributed to the ability of fine ceramics to fulfill an attractive, extreme, and distinguishing combination of application requirements. This is impelled by ensuring a suitable arrangement of thermomechanical, thermoelectric, and electromechanical properties. As a result, the reliability, durability, and useful lifetime extension of a critical structure or system are expected. In this context, engineered ceramic appliances consist of three main purposes in aeronautical and aerospace fields: thermal protection systems (TPS), thermal protection barriers (TBC), and dielectric barrier discharge (DBD) plasma actuators. Consequently, this research provides an extensive discussion and review of the referred applications, i.e., TPS, TBC, and DBD, and discusses the concept of multifunctional advanced ceramics for future engineering needs and perspectives.

Novel RDD Pulse Shaping Method for High-Power High-Voltage Pulse Current Power Supply in DBD Application

High-voltage pulse power supplies are key power input devices for the study and application of discharge plasma. A high-voltage pulse current power supply (HV-PCPS) with an energy storage pulse transformer based on flyback topology can output microsecond pulsewidths with high-power, ultrahigh voltage, and high reliability, which are suitable for most dielectric barrier discharge (DBD) plasma applications. However, during the process of DBD driven by an HV-PCPS based on an energy storage pulse transformer, the output pulse voltage waveform quality is poor, making it not suitable for stable discharge long-term operation. This article aims to solve the aforementioned problem and proposes a novel resistor–diode–diode (RDD) shaping method. Not only can this novel method solve the problem of poor quality of the output pulse power from the HV-PCPS, guaranteeing stable discharge for various DBD electrodes, it can also limit the maximum output voltage amplitude. This prevents overvoltage breakdown when the output terminal is in an open state or a light load state because the HV-PCPS is acting as a current source. This article also analyzes the effectiveness of an RDD branch when solving the problem in theory, and gives a detailed parameter design method. Finally, a 30-kV HV-PCPS prototype is built to verify the effectiveness of the proposed RDD pulse shaping method. The average pulse power output of the whole prototype is greatly improved, and it can achieve an average pulse power output of 1 kW. Furthermore, the electrode loads of different DBD reactors can be driven by this technology.

Analysis and Design of a Compact Bipolar High-Voltage Short-Pulse Power Supply for DBD Application

As known, a short-pulse excitation voltage with a high rising rate and idle time [At this period, the current of dielectric barrier discharge (DBD) loads is equal to or close to zero] simultaneously is conducive to taking advantage of the potential of DBD loads. However, how to use a simple and classical topology to provide such an excitation voltage is rarely researched and is still an important issue for DBD application fields. The adoption of a set of modes that can generate the excitation voltage in a half-bridge-inverter and the design of a control strategy for the inverter are the main contributions of this article. Through mode analysis, the characteristics of the power supply are discussed, and a design process of the power supply is demonstrated. The simulation and experimental results show that not only an expected bipolar pulse excitation voltage can be generated, but also the soft-switching of all power switches is realized. Compared with other types of power supplies, the potential of the excimer lamp can be well developed with the presented power supply, and the power supply has the advantages of a more compact structure, fewer components and higher working frequency.

Circuit analysis and modeling of a soft-switching pulse power supply based on full-bridge inverter for DBD application

PurposeHow to use a simple and classical topology to provide a high-efficiency excitation voltage for dielectric barrier discharge (DBD) loads is one of the primary problems to be solved for DBD application fields.Design/methodology/approachTo address the issue, a set of modes that can generate a high-efficiency pulse excitation voltage in a full-bridge inverter are adopted. With the set of modes, the unique equivalent circuit of DBD loads and the parasitic parameter of the step-up transformer can be fully used. Based on the set of modes, a control strategy for the full-bridge inverter is designed. To test the performance of the power supply, a simulation model is established and an experimental prototype is made with a DBD excimer lamp.FindingsThe simulation and experimental results show that not only a high-efficiency excitation voltage can be generated for the DBD load, but also the soft switching of all power switch is realized. Besides this, with the set of modes and the proposed control strategy, the inverter can operate in a high frequency. Compared with other types of power supplies, the power supply used in the paper can fully take advantage of the potential of the excimer lamp at the same input power.Originality/valueThis work considers that how to use a simple and classical topology to provide a high-efficiency excitation voltage for DBD loads is one of the primary problems to be solved for DBD application fields.

Application of Dielectric Barrier Discharge in Rhb Degradation: Performance Optimization, Degradation Mechanism and Pathways

Application of Dielectric Barrier Discharge in Rhb Degradation: Performance Optimization, Degradation Mechanism and Pathways

Acoustic streaming flow generated by surface dielectric barrier discharge in quiescent air

Dielectric barrier discharge (DBD) is closely related to our daily lives and has been known for more than a century and a half since Ernst Werner von Siemens first discovered it. Based on general knowledge, DBD can be used for disinfection in medicine, de-pollution of gas streams in the environment, and flow control in aeronautics using its induced products, which includes ozone, electrons, and ionic winds, respectively. However, compared with the other characteristics of DBD, the acoustic effects are often ignored as there are nearly no relevant investigations. Here, we demonstrate that ultrasound can be generated using a single DBD plasma actuator as driven by sinusoidal high-voltage power with a voltage amplitude of 20 kVp-p at a frequency of 500 Hz using a pressure-field microphone and the high-accuracy phase-lock image freezing Schlieren technique. Most importantly, this is the first time that acoustic streaming flow created by DBD as associated with induced ultrasound is observed using particle image velocimetry. This could produce new research areas to expand the range of applications of DBD based on potential interest in acoustic streaming for microfluidic systems in biology, chemistry, and medicine.

A comparative study on the degradation of 2,4-dichlorophenol and 2,5-dichlorophenol using DBD non-thermal plasma reactor

The dichlorophenol compound group (DCP) is one of the pollutants contained in industrial wastewater. This component is difficult to degrade in the environment, subsequently leading to hazards and a severe impact on human health. Based on the location of the chlorine atom in the aromatic ring, the variety present in some isomers ought to be removed from the water, in order to reduce the impact. Therefore, the technology adopted to eliminate the DCP concentration levels in wastewater includes the application of Dielectric Barrier Discharge (DBD) plasma reactor of high efficiency. This set up implements advanced oxidation processes (AOPs) by relying on highly active species, specifically ‧OH and O3. The aim of this study, therefore, is to compare the effectiveness of DBD reactors in the degradation activity on isomer 2,4-DCP and 2,5-DCP under acidic (pH 4) and alkaline (pH 10) conditions. The results showed the highest percentage removal (89.05%) after 120 minutes process of 2.5-DCP degradation, under the following conditions: pH 10; flow rate 50 mL/minute; airflow rate of 2.5 L/min; plasmatron voltage of 19 kV. Under similar circumstances, 2,4-DCP was reduced by 86.95%. In addition, the COD content in the waste material reached 46.88% and 46.14%, respectively.

Atmospheric Pressure Dielectric Barrier Discharges for the Deposition of Organic Plasma Polymer Coatings for Biomedical Application

Atmospheric pressure dielectric barrier discharges (DBDs) are proving to have great potential in the bioengineering and medical field for functionalisation of biomaterials. The ability to operate in open atmosphere in a continuous process makes DBD a preferred method over conventional surface engineering techniques and low pressure plasma material processing. DBDs are characterised by configurations with a dielectric layer between conducting electrodes in the discharge path. The success in the application of DBDs in the modification of biomaterials has been demonstrated in many research articles. This review surveys DBD plasma-based methods for the production of organic polymer coatings on biomaterials that contain reactive chemical species useful for subsequent biomedical application. In the first part of this paper, a general introduction in the field of surface engineering will be given. The review then focuses on a brief overview of plasma-based deposition techniques including those of atmospheric plasmas. A brief knowledge of the operation and formation of DBDs are then presented. The application of DBDs for the deposition of coatings with different functionalities and for different biomedical applications are reviewed. The current challenges related to the discharge characteristics and thin organic coatings specific to stability and ageing processes are also discussed.

10 kV SiC MOSFET Evaluation for Dielectric Barrier Discharge Transformerless Power Supply

At low pressure, cold plasmas are used for a wide range of applications such as coating, flow control, or microelectronics. Currently, this industry requires expensive vacuum systems which consume energy and time, and therefore it is very appealing to develop similar processes at atmospheric pressure. Under this condition, dielectric barrier discharge (DBD) is one of the best ways to obtain a cold plasma. The dielectric barriers naturally limit the current, and then the plasma temperature. Unfortunately, at atmospheric pressure the discharge ignition between the electrodes requires high voltage, which is generally obtained through a step-up transformer. The parasitic elements of this device exclude a smart control for the discharge. In order to overcome this default, we analyze the performance of a transformerless power supply developed with a recently released single-chip high-voltage semiconductor. The circuit uses only two high-voltage switches synthesized by means of the 10 kV SiC MOSFET (Metal Oxide Semiconductor Field Effect Transistor). The design and implementation of the electric converter are presented and validated with experiments carried out on UV excimer DBD lamps. Then, the performances of the 10 kV SiC switches are analyzed and the relevance of this device for DBD applications is discussed.

Application of dielectric barrier discharge (DBD) plasma packed with glass and ceramic pellets for SO2 removal at ambient temperature: optimization and modeling using response surface methodology

Air pollution is a major health problem in developing countries and has adverse effects on human health and the environment. Non-thermal plasma is an effective air pollution treatment technology. In this research, the performance of a dielectric barrier discharge (DBD) plasma reactor packed with glass and ceramic pellets was evaluated in the removal of SO2 as a major air pollutant from air in ambient temperature. The response surface methodology was used to evaluate the effect of three key parameters (concentration of gas, gas flow rate, and voltage) as well as their simultaneous effects and interactions on the SO2 removal process. Reduced cubic models were derived to predict the SO2 removal efficiency (RE) and energy yield (EY). Analysis of variance results showed that the packed-bed reactors (PBRs) studied were more energy efficient and had a high SO2 RE which was at least four times more than that of the non-packed reactor. Moreover, the results showed that the performance of ceramic pellets was better than that of glass pellets in PBRs. This may be due to the porous surface of ceramic pellets which allows the formation of microdischarges in the fine cavities of a porous surface when placed in a plasma discharge zone. The maximum SO2 RE and EY were obtained at 94% and 0.81 g kWh−1, respectively under the optimal conditions of a concentration of gas of 750 ppm, a gas flow rate of 2 l min−1, and a voltage of 18 kV, which were achieved by the DBD plasma packed with ceramic pellets. Finally, the results of the model’s predictions and the experiments showed good agreement.

Demonstration of knock intensity mitigation through dielectric barrier discharge reformation in an RCEM

A knock intensity mitigation effect resulting from the application of dielectric barrier discharge (DBD) was experimentally demonstrated. The DBD was utilized to reform fuel–air premixtures. A rapid compression and expansion machine (RCEM) was used for the demonstration experiment. A rectangular combustion channel was installed in the RCEM's cylinder to observe flame propagation and end-gas auto-ignition behavior. The effect of the DBD was investigated by installing a plug-shaped DBD reactor in the combustion chamber. Part of the fuel-air mixture was reformed by the DBD and diffused in the chamber, and the combustion behavior was observed by a color and a monochrome high-speed camera with several different interference filters. In ordinary end-gas auto-ignition, a hot flame rapidly appears throughout the end-gas region, and generates strong pressure oscillation; whereas, in the present study, when the DBD was applied, the magnitude of the pressure oscillation decreased and a blue flame was generated in the end gas before full end-gas auto-ignition. The onset time of the blue flame, and the interval between the onset and the hot flame's appearance, depended on the fuel and initial temperature. The effect was investigated in the case of a primary reference fuel, surrogate gasoline, and n-butane lean mixture; however, though the magnitude of the effect varied, the mitigation effect was demonstrated for every fuel-air mixture. The proposed method is therefore expected to mitigate knocking in internal combustion engines and contribute to greater thermal efficiency.

Atmospheric pressure Townsend discharges as a promising tool for the one‐step deposition of antifogging coatings from N2O/TMCTS mixtures

AbstractThe need to ensuring the “see‐through” property of transparent materials when exposed to sudden temperature changes or very humid conditions has encouraged the development of antifogging strategies, such as the deposition of (super)hydrophilic coatings. However, despite the effectiveness of these coatings in combating the effects of fogging, most of the coating techniques explored to date are typically time‐consuming and environment‐unfriendly. Bearing this in mind, we demonstrate that the application of dielectric barrier discharges operated at atmospheric pressure proves to be successful in preparing antifogging coatings on glass samples from 1,3,5,7‐tetramethylcyclotetrasiloxane (TMCTS) and nitrous oxide (N2O). The antifogging performance of the coatings was found to be governed by the [N2O]/[TMCTS] ratio and not by the [N2O] + [TMCTS] sum. Coatings prepared under a [N2O]/[TMCTS] = 30 were superhydrophilic (water contact angles ≈ 5°–10°) due to surface silanol groups and endowed glass samples with a superior antifogging property, as revealed by the ASTM F 659‐06 test. In contrast, because of the lesser hydrophilicity (water contact angles ≈ 60°), coatings prepared under a [N2O]/[TMCTS] = 10 did not endow glass samples with antifogging property. Regardless of the deposition conditions, the plasma‐deposited coatings displayed crack‐free smooth surfaces (Rrms = 2−4 nm).

Dynamic evolution of vortex structures induced by tri-electrode plasma actuator**Project supported by the National Natural Science Foundation of China (Grant No. 51607188), the Foundation for Key Laboratories of National Defense Science and Technology, China (Grant No. 614220202011801), the Shaanxi Provincial Natural Science Basic Research Program, China (Grant No. 2019JM-393), the Shaanxi Provincial Key Industry Innovation, Chain (Grant No. 2017ZDCXL-GY-06-01), and

Plasma flow control is a new type of active flow control approach based on plasma pneumatic actuation. Dielectric barrier discharge (DBD) actuators have become a focus of international aerodynamic research. However, the practical applications of typical DBDs are largely restricted due to their limited discharge area and low relative-induced velocity. The further improvement of performance will be beneficial for engineering applications. In this paper, high-speed schlieren and high-speed particle image velocimetry (PIV) are employed to study the flow field induced by three kinds of plasma actuations in a static atmosphere, and the differences in induced flow field structure among typical DBD, extended DBD (EX-DBD), and tri-electrode sliding discharge (TED) are compared. The analyzing of the dynamic evolution of the maximum horizontal velocity over time, the velocity profile at a fixed horizontal position, and the momentum and body force in a control volume reveals that the induced velocity peak value and profile velocity height of EX-DBD are higher than those of the other two types of actuation, suggesting that EX-DBD actuation has the strongest temporal aerodynamic effect among the three types of actuations. The TED actuation not only can enlarge the plasma extension but also has the longest duration in the entire pulsed period and the greatest influence on the height and width of the airflow near the wall surface. Thus, the TED actuation has the ability to continuously influencing a larger three-dimensional space above the surface of the plasma actuator.