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Experimental and numerical investigation of a self-supplementing dual-cavity plasma synthetic jet actuator
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作者 郑博睿 张倩 +2 位作者 赵太飞 宋国正 陈全龙 《Plasma Science and Technology》 SCIE EI CAS CSCD 2023年第2期172-178,共7页
The primary issue regarding the plasma synthetic jet actuator(PSJA)is its performance attenuation at high frequencies.To solve this issue,a self-supplementing,dual-cavity,plasma synthetic jet actuator(SD-PSJA)is desig... The primary issue regarding the plasma synthetic jet actuator(PSJA)is its performance attenuation at high frequencies.To solve this issue,a self-supplementing,dual-cavity,plasma synthetic jet actuator(SD-PSJA)is designed,and the static properties of the SD-PSJA are investigated through experiments and numerical simulations.The pressure measurement shows that the SD-PSJA has two saturation frequencies(1200 Hz and 2100 Hz),and the experimental results show that both the saturation frequencies decrease as the volume of the bottom cavity of the SD-PSJA increases.As the size of the supplement hole increases,the first saturation frequency increases continuously,while the second saturation frequency shows a trend of first decreasing and then increasing.Numerical simulations show that the working process of the SD-PSJA is similar to that of the PSJA,but the volume of the cavity in the SD-PSJA is smaller than that of the PSJA;the SD-PSJA can supplement air to the top cavity through two holes,thus reducing the refresh time and effectively improving the jet intensity of the actuator at high frequencies. 展开更多
关键词 plasma flow control plasma synthetic jet actuator pressure measurements numerical simulations
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EXPERIMENT ON FLOW CHARACTERISTICS OF SYNTHETIC JET DRIVEN BY PIEZOELECTRIC MEMBRANE
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作者 谭晓茗 张靖周 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2007年第3期199-204,共6页
The characteristics of the flowfields of a synthetic jet actuator are experimentally investigated with the slot-nozzle driven by the piezoelectric membrane. The particle image velocimetry (PIV) and the hot-wire anem... The characteristics of the flowfields of a synthetic jet actuator are experimentally investigated with the slot-nozzle driven by the piezoelectric membrane. The particle image velocimetry (PIV) and the hot-wire anemometer are utilized to measure the flowfields and the velocity profiles of the actuator with different actuating factors. Analytical results show that pairs of counter-rotating vortices are generated near the nozzle. With the development of the synthetic ject, the synthetic jet rapidly spreads in the slot-width direction; while in the slot-length direction, it contracts firstly and slowly spreads. The centerline velocity distribution has a up-down tendency varying with axial distances, and accelerates to its maximum at z/b= 10. The transverse velocity profile across the slot-width is centro-symmetric and self-similar. However, the velocity profiles across the slot-length are saddle-like near the nozzle. It shows that there are two resonance frequencies for the actuator. If the actuator works with the resonance frequency, the vorticity and the velocity of the synthetic jet are higher than those of other frequencies. Compared with the continuous jet, the synthetic jet shows special flow characteristics. 展开更多
关键词 synthetic jet flow characteristics velocity distribution particle image velocimetry
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Jet Vectoring Control Using a Novel Synthetic Jet Actuator 被引量:13
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作者 LUO Zhen-bing XIA Zhi-xun XIE Yong-gao 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2007年第3期193-201,共9页
A primary air jet vectoring control system with a novel synthetic jet actuator (SJA) is presented and simulated numerically. The results show that, in comparison with an existing traditional synthetic jet actuator, ... A primary air jet vectoring control system with a novel synthetic jet actuator (SJA) is presented and simulated numerically. The results show that, in comparison with an existing traditional synthetic jet actuator, which is able to perform the duty of either "push" or "pull", one novel synthetic jet actuator can fulfill both "push" and "pull" functions to vector the primary jet by shifting a slide block inside it. Therefore, because the new actuator possesses greater efficiency, it has potentiality to replace the existing one in various appli- cations, such as thrust vectoring and the reduction of thermal signature. Moreover, as the novel actuator can fulfill those functions that the existing one can not, it may well be expected to popularize it into more flow control systems. 展开更多
关键词 jet vectoring control synthetic jet actuator slide block flow control
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Experimental Characterization of the Plasma Synthetic Jet Actuator 被引量:12
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作者 金迪 李应红 +4 位作者 贾敏 宋慧敏 崔巍 孙权 李凡玉 《Plasma Science and Technology》 SCIE EI CAS CSCD 2013年第10期1034-1040,共7页
The plasma synthetic jet is a novel active flow control method because of advantages such as fast response, high frequency and non-moving parts, and it has received more attention recently, especially regarding its ap... The plasma synthetic jet is a novel active flow control method because of advantages such as fast response, high frequency and non-moving parts, and it has received more attention recently, especially regarding its application to high-speed flow control. In this paper, the experimental characterization of the plasma synthetic jet actuator is investigated. The actuator consists of a copper anode, a tungsten cathode and a ceramic shell, and with these three parts a cavity can be formed inside the actuator. A pulsed-DC power supply was adopted to generate the arc plasma between the electrodes, through which the gas inside was heated and expanded from the orifice. Discharge parameters such as voltage and current were recorded, respectively, by voltage and current probes. The schlieren system was used for flow visualization, and jet velocities with different discharge parameters were measured. The schlieren images showed that the strength of plasma jets in a series of pulses varies from each other. Through velocity measurement, it is found that at a fixed frequency, the jet velocity hardly increases when the discharge voltage ranges from 16 kV to 20 kV. However, with the discharge voltage fixed, the jet velocity suddenly decreases when the pulse frequency rises above 500 Hz, whereas at other testing frequencies no such decrease was observed. The maximum jet velocity measured in the experiment was up to 110 m/s, which is believed to be effective for high-speed flow control. 展开更多
关键词 plasma aerodynamic actuation synthetic jet pulsed-DC discharge jet veloc-ity
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Separation control using synthetic vortex generator jets in axial compressor cascade 被引量:11
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作者 Xinqian Zheng Sheng Zhou +2 位作者 Anping Hou Zhengli Jiang Daijun Ling 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2006年第6期521-527,共7页
An experimental investigation conducted in a high-speed plane cascade wind tunnel demonstrates that unsteady flow control by using synthetic (zero mass flux) vortex generator jets can effectively improve the aerodyn... An experimental investigation conducted in a high-speed plane cascade wind tunnel demonstrates that unsteady flow control by using synthetic (zero mass flux) vortex generator jets can effectively improve the aerodynamic performances and reduce (or eliminate) flow separation in axial compressor cascade. The Mach number of the incoming flow is up to 0.7 and most tested cases are at Ma = 0.3. The incidence is 10° at which the boundary layer is separated from 70% of the chord length. The roles of excitation frequency, amplitude, location and pitch angle are investigated. Preliminary results show that the excitation amplitude plays a very important role, the optimal excitation location is just upstream of the separation point, and the optimal pitch angle is 35°. The maximum relative reduction of loss coefficient is 22.8%. 展开更多
关键词 Flow control COMPRESSOR synthetic jet
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Influence of high-voltage pulse parameters on the propagation of a plasma synthetic jet 被引量:5
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作者 Shuqun WU Xueyuan LIU +3 位作者 Guowang HUANG Chang LIU Weijie BIAN Chaohai ZHANG 《Plasma Science and Technology》 SCIE EI CAS CSCD 2019年第7期60-68,共9页
In this work, a typical pin-to-pin plasma synthetic jet in static air is excited by a pulsed DC power supply. The influences of the pulse rising time, the amplitude and the repetition frequency of the pulse voltage on... In this work, a typical pin-to-pin plasma synthetic jet in static air is excited by a pulsed DC power supply. The influences of the pulse rising time, the amplitude and the repetition frequency of the pulse voltage on the jet flow have been investigated. First, using a high-speed Schlieren imaging technique, the induced shock waves and the fast jet flow generated by the plasma synthetic jet are characterized. With a deposited energy of 44 m J per pulse, the velocity of the shock wave and the maximum velocity of the jet flow reach 320 m s-1 and 100 m s-1,respectively. Second, when the applied voltage increases from 12.8 kV to 16 kV, the maximum jet velocity increases from 66 m s-1 to 93 m s-1. On the other hand, as the pulse rising time varies from 50 ns to 500 ns, or the pulse repetition frequency increases from 5 Hz to 40 Hz, the jet velocity induced by the plasma synthetic jet is weakly dependent. In addition, a comparative study of the plasma synthetic jets using three commercial pulsed power supplies(XJ-15, NPG-18, and PG-30) is implemented. It reveals that the maximum jet velocity of 120 m s-1 is obtained in the case of PG-30, with the longest pulse rising time and the lowest breakdown voltage, while the maximum velocity of 33 m s-1 is detected in the case of NPG-18, even though it has the shortest pulse rising time and the highest breakdown voltage. 展开更多
关键词 SPARK DISCHARGE PLASMA synthetic jet nanosecond PULSED power
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Physical factors of primary jet vectoring control using synthetic jet actuators 被引量:3
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作者 夏智勋 罗振兵 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2007年第7期907-920,共14页
A primary jet vectoring using synthetic jet actuators with different exit configurations was investigated, and the main physical factors influencing jet vectoring were analyzed and summarized. The physical factors of ... A primary jet vectoring using synthetic jet actuators with different exit configurations was investigated, and the main physical factors influencing jet vectoring were analyzed and summarized. The physical factors of the pressure difference, the location and area of the lower pressure region, the component of the synthetic jet momentum and the entrainment ratio of the synthetic jet flow to primary jet flow directly control the vectoring force and the vectoring angle. Three characteristic parameters of the synthetic jet contribute to the pressure difference and the area of the lower pressure region Both the extension step and slope angle of the actuator exit have functions of regulating the location of the lower pressure region, the area of the lower pressure region, and the entrainment ratio of the synthetic jet flow to primary jet flow. The slope angle of the actuator exit has additional functions of regulating the component of the synthetic jet momentum. Based upon analyzing the physical factors of jet vectoring control with synthetic jets, the source variables of the physical factors were established. A preparatory control model of jet vectoring using synthetic jet actuator was presented, and it has the benefit of explaining the efficiency of jet vectoring using synthetic jet actuator with source variables at different values, and it indicates the optimal actuator is taking full advantage of the regulating function. 展开更多
关键词 flow control synthetic jet jet vectoring physical factor
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Numerical simulation on micromixer based on synthetic jet 被引量:1
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作者 Minghou Liu Chen Xie Xiangfeng Zhang Yiliang Chen 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2008年第6期629-636,共8页
This paper studied a concept of micromixer with a synthetic jet placed at the bottom of a rectangular channel. Due to periodic ejections from and suctions into the channel, the fluids are mixed effectively. To study t... This paper studied a concept of micromixer with a synthetic jet placed at the bottom of a rectangular channel. Due to periodic ejections from and suctions into the channel, the fluids are mixed effectively. To study the effects of the inlet velocity, the jet intensity and frequency, and the jet location on the mixing efficiency, 3-D numerical simulations of the micromixer have been carried out. It has been found that when the jet intensity and the frequency are fixed, the mixing efficiency increases when Re 〈 50, and decreases when Re 〉 50 with the best mixing efficiency achieved at Re = 50. When the ratio of the jet velocity magnitude to the inlet velocity is taken as 10 and the jet frequency is 100 Hz, the mixing index reaches the highest value. It has also been found that to get better mixing efficiency, the orifice of the synthetic jet should be asymmetrically located away from the channel's centerline. 展开更多
关键词 MICROMIXER synthetic jet Mixing index
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Numerical investigation of flow over a two-dimensional square cylinder with a synthetic jet generated by a bi-frequency signal 被引量:2
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作者 Yiran LU Yuan QU +1 位作者 Jiangsheng WANG Jinjun WANG 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2022年第10期1569-1584,共16页
The flow around a square cylinder with a synthetic jet positioned at the rear surface is numerically investigated with the unsteady Reynolds-averaged Navier-Stokes(URANS)method.Instead of the typical sinusoidal wave,a... The flow around a square cylinder with a synthetic jet positioned at the rear surface is numerically investigated with the unsteady Reynolds-averaged Navier-Stokes(URANS)method.Instead of the typical sinusoidal wave,a bi-frequency signal is adopted to generate the synthetic jet.The bi-frequency signal consists of a basic sinusoidal wave and a high-frequency wave.Cases with various amplitudes of the high-frequency component are simulated.It is found that synthetic jets actuated by bi-frequency signals can realize better drag reduction with lower energy consumption when appropriate parameter sets are applied.A new quantity,i.e.,the actuation efficiency Ae,is used to evaluate the controlling efficiency.The actuation efficiency Ae reaches its maximum of 0.2668 when the amplitude of the superposed high-frequency signal is 7.5%of the basic signal.The vortex structures and frequency characteristics are subsequently analyzed to investigate the mechanism of the optimization of the bi-frequency signal.When the synthetic jet is actuated by a single-frequency signal with a characteristic velocity of 0.112 m/s,the wake is asymmetrical.The alternative deflection of vortex pairs and the peak at half of the excitation frequency in the power spectral density(PSD)function are detected.In the bi-frequency cases with the same characteristic velocity,the wake gradually turns to be symmetrical with the increase in the amplitude of the high-frequency component.Meanwhile,the deflection of the vortex pairs and the peak at half of the excitation frequency gradually disappear as well. 展开更多
关键词 synthetic jet flow control signal superposition vortex dynamics
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Active Stall Control System on NACA0012 by Using Synthetic Jet Actuator 被引量:1
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作者 Hiroaki Hasegawa Shigeru Obayashi 《Journal of Flow Control, Measurement & Visualization》 2019年第1期61-72,共12页
Flow separation is typically an undesirable phenomenon, and boundary layer control is an important technique for the separation problems on airfoils. The synthetic jet actuator is considered as a promising candidate f... Flow separation is typically an undesirable phenomenon, and boundary layer control is an important technique for the separation problems on airfoils. The synthetic jet actuator is considered as a promising candidate for flow control applications because of its compact nature and ability to generate momentum without the need for fluidic plumbing. In the present study, an active separation control system using synthetic jets is proposed and practically applied to the stall control of the NACA0012 airfoil in a wind tunnel test. In our proposed system, the flow conditions (stalled or unstalled) can be judged by calculating from two static pressure holes on the airfoil upper surface alone. The experimental results indicate that the maximum lift coefficient increases by 11% and the stall angle rises by 4&#176;in contrast to the case under no control. It is confirmed that our proposed system can suppress the stall on the NACA0012 airfoil and that the aerodynamic performance of the airfoil can be enhanced. The proposed system can also be operated prior to the onset of stall. Therefore, separation control is always attained with no stall for all flow fields produced by changing the angle of attack that were examined. 展开更多
关键词 ACTIVE Control AIRFOIL LIFT Separation STALL synthetic jet
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Experimental investigation on drag reduction in a turbulent boundary layer with a submerged synthetic jet 被引量:1
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作者 Biao-Hui Li Kang-Jun Wang +1 位作者 Yu-Fei Wang Nan Jiang 《Chinese Physics B》 SCIE EI CAS CSCD 2022年第2期453-459,共7页
This work investigates the active control of a fully developed turbulent boundary layer by a submerged synthetic jet actuator.The impacts of the control are explored by measuring the streamwise velocities using partic... This work investigates the active control of a fully developed turbulent boundary layer by a submerged synthetic jet actuator.The impacts of the control are explored by measuring the streamwise velocities using particle image velocimetry,and reduction of the skin-friction drag is observed in a certain range downstream of the orifice.The coherent structure is defined and extracted using a spatial two-point correlation function,and it is found that the synthetic jet can efficiently reduce the streamwise scale of the coherent structure.Proper orthogonal decomposition analysis reveals that large-scale turbulent kinetic energy is significantly attenuated with the introduction of a synthetic jet.The conditional averaging results show that the induction effect of the prograde vortex on the low-speed fluid in a large-scale fluctuation velocity field is deadened,thereby suppressing the bursting process near the wall. 展开更多
关键词 synthetic jet active control turbulent boundary layer drag reduction
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Influence of air pressure on the performance of plasma synthetic jet actuator 被引量:1
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作者 李洋 贾敏 +4 位作者 吴云 李应红 宗豪华 宋慧敏 梁华 《Chinese Physics B》 SCIE EI CAS CSCD 2016年第9期429-436,共8页
Plasma synthetic jet actuator(PSJA) has a wide application prospect in the high-speed flow control field for its high jet velocity.In this paper,the influence of the air pressure on the performance of a two-electrod... Plasma synthetic jet actuator(PSJA) has a wide application prospect in the high-speed flow control field for its high jet velocity.In this paper,the influence of the air pressure on the performance of a two-electrode PSJA is investigated by the schlieren method in a large range from 7 k Pa to 100 k Pa.The energy consumed by the PSJA is roughly the same for all the pressure levels.Traces of the precursor shock wave velocity and the jet front velocity vary a lot for different pressures.The precursor shock wave velocity first decreases gradually and then remains at 345 m/s as the air pressure increases.The peak jet front velocity always appears at the first appearance of a jet,and it decreases gradually with the increase of the air pressure.A maximum precursor shock wave velocity of 520 m/s and a maximum jet front velocity of 440 m/s are observed at the pressure of 7 k Pa.The averaged jet velocity in one period ranges from 44 m/s to 54 m/s for all air pressures,and it drops with the rising of the air pressure.High velocities of the precursor shock wave and the jet front indicate that this type of PSJA can still be used to influence the high-speed flow field at 7 k Pa. 展开更多
关键词 plasma synthetic jet actuator air pressure performance schlieren method
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Effect of gas compressibility on the characteristics of a synthetic jet flow
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作者 丁英涛 苏日娜 李博 《Journal of Beijing Institute of Technology》 EI CAS 2012年第4期442-446,共5页
Numerical simulations are performed to investigate the effects of gas compressibility on the synthetic jet flow. A slot synthetic jet and a circular orifice synthetic jet are simulated assuming 2D and axis-symmetric b... Numerical simulations are performed to investigate the effects of gas compressibility on the synthetic jet flow. A slot synthetic jet and a circular orifice synthetic jet are simulated assuming 2D and axis-symmetric behavior. The velocity of orifice, frequency response and the compressibility are studied through simulation. The numerical results are validated against existing experimental and analytical data, and good agreement are obtained, Gas compressibility effects on the synthetic jet flow are discussed. In conclusion, for the two kinds of different synthetic jets studied in this paper, the critical values of Mach number are 0. 082 and 0. 033. 展开更多
关键词 synthetic jet gas compressibility gumerical simulation Mach number
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Effects of single synthetic jet on turbulent boundary layer
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作者 Jin-Hao Zhang Biao-Hui Li +1 位作者 Yu-Fei Wang Nan Jiang 《Chinese Physics B》 SCIE EI CAS CSCD 2022年第7期379-388,共10页
The turbulent boundary layer(TBL)is actively controlled by the synthetic jet generated from a circular hole.According to the datasets of velocity fields acquired by a time-resolved particle image velocimetry(TR-PIV)sy... The turbulent boundary layer(TBL)is actively controlled by the synthetic jet generated from a circular hole.According to the datasets of velocity fields acquired by a time-resolved particle image velocimetry(TR-PIV)system,the average drag reduction rate of 6.2%in the downstream direction of the hole is obtained with control.The results of phase averaging show that the synthetic jet generates one vortex pair each period and the consequent vortex evolves into hairpin vortex in the environment with free-stream,while the reverse vortex decays rapidly.From the statistical average,it can be found that a low-speed streak is generated downstream.Induced by the two vortex legs,the fluid under them converges to the middle.The drag reduction effect produced by the synthetic jet is local,and it reaches a maximum value at x^(+)=400,where the drag reduction rate reaches about 12.2%.After the extraction of coherent structure from the spatial two-point correlation analysis,it can be seen that the synthetic jet suppresses the streamwise scale and wall–normal scale of the large scale coherent structure,and slightly weakens the spanwise motion to achieve the effect of drag reduction. 展开更多
关键词 turbulent boundary layer synthetic jet hairpin vortex drag reduction
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Effect of synthetic fibers on resisting scour caused by horizontal jet
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作者 Amin Ghassemi Mohsen Nasrabadi +1 位作者 Mohammad Hossein Omid Ali Raeesi Estabragh 《Water Science and Engineering》 EI CAS CSCD 2022年第2期152-160,共9页
Given that the development of scour downstream of hydraulic structures increases the risk of structural damage,it is important to find cost-effective and environmental approaches to reduce this risk.This study aimed t... Given that the development of scour downstream of hydraulic structures increases the risk of structural damage,it is important to find cost-effective and environmental approaches to reduce this risk.This study aimed to experimentally evaluate the effect of synthetic fibers on the scour profile downstream of a sluice gate with a rigid apron.Experiments were performed with the same Froude number and with different weight percentages of synthetic fibers on both non-cohesive and cohesive sediments.One uniform sand was used as the non-cohesive sediment,and three different cohesive sediments were prepared by mixing different percentages of kaolinite soil with the used sand.The scouring experiments showed that the presence of synthetic fibers did not considerably affect the scour hole dimension in non-cohesive sediments.Evaluation of the scour in the cohesive sediments in silty sand(SM)texture found that an increase in the percentage of silt reduced the scour hole dimensions.The effect of synthetic fibers on scour of SM-texture-based sediments was also investigated,and the results showed that increasing the percentage of synthetic fibers decreased the scour hole dimensions.In addition,the cohesive sediments in SM texture did not have a similar non-dimensional scour profile,and the presence of synthetic fibers did not significantly affect the scour hole. 展开更多
关键词 Local scouring synthetic fibers Horizontal jet SM soil texture Scour profile
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Parametric study of high-frequency characteristics of plasma synthetic jet actuator
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作者 Guozheng SONG Haohua ZONG +3 位作者 Hua LIANG Zhi SU Like XIE Xing ZHENG 《Plasma Science and Technology》 SCIE EI CAS CSCD 2021年第12期140-149,共10页
A major issue of plasma synthetic jet actuator(PSJA)is the severe performance deterioration at high working frequency.In this study,experiments and numerical simulation are combined together to investigate the influen... A major issue of plasma synthetic jet actuator(PSJA)is the severe performance deterioration at high working frequency.In this study,experiments and numerical simulation are combined together to investigate the influence of thermal conductivity,throat length(Lth)and discharge duration(Td)on the high-frequency characteristics of PSJA.Results show that the variation of the actuator thermal conductivity and discharge duration will not alter the saturation frequency of the actuator,whereas decreasing the throat length results in an increase of the saturation frequency.For a short-duration capacitive discharge of 1.7μs,a clear shock wave is issued from the orifice,followed by a weak jet.As a comparison,when the discharge duration is increased up to 202.6μs,a strong jet column is formed and no obvious shock wave can be visualized.Based on numerical simulation results,it becomes clear that the long-duration pulse-DC discharge is able to heat the cavity gas to a much higher temperature(3141 K)than capacitive discharge,greatly improving the conversion efficiency of the arc discharge energy to the internal energy of the cavity gas.In addition,high-speed Schlieren imaging is deployed to study the performance degradation mechanism of PSJA at high working frequency.Monitor of the exit jet grayscale indicates that as long as the saturation frequency is exceeded,the actuator becomes unstable due to insufficient refresh time.The higher the discharge frequency,the more frequently the phenomenon of‘misfires’will occur,which explains well the decaying jet total pressure at above saturation frequency. 展开更多
关键词 thermal conductivity throat length discharge duration plasma synthetic jet saturation frequency
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Control of flow separation over a wing model with plasma synthetic jets
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作者 Zhi SU Guozheng SONG +5 位作者 Haohua ZONG Hua LIANG Jun LI Like XIE Xuecheng LIU Weiliang KONG 《Plasma Science and Technology》 SCIE EI CAS CSCD 2022年第6期135-147,共13页
An array of 30 plasma synthetic jet actuators(PSJAs)is deployed using a modified multichannel discharge circuit to suppress the flow separation over a straight-wing model.The lift and drag of the wing model are measur... An array of 30 plasma synthetic jet actuators(PSJAs)is deployed using a modified multichannel discharge circuit to suppress the flow separation over a straight-wing model.The lift and drag of the wing model are measured by a force balance,and the velocity fields over the suction surface are captured by a particle imaging velocimetry system.Results show that the flow separation of the straight wing originates from the middle of the model and expands towards the wingtips as the angle of attack increases.The flow separation can be suppressed effectively by the PSJAs array.The best flow control effect is achieved at a dimensionless discharge frequency of F^+=1,with the peak lift coefficient increased by 10.5%and the stall angle postponed by 2°.To further optimize the power consumption of the PSJAs,the influence of the density of PSJAs on the flow control effect is investigated.A threshold of the density exits(with the spanwise spacing of PSJAs being 0.2 times of the chord length in the current research),below which the flow control effect starts to deteriorate remarkably.In addition,for comparison purposes,a dielectric barrier discharge(DBD)plasma actuator is installed at the same location of the PSJAs.At the same power consumption,4.9%increase of the peak lift coefficient is achieved by DBD,while that achieved by PSJAs reaches 5.6%. 展开更多
关键词 flow separation plasma synthetic jet DENSITY dielectric barrier discharge
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Design and Performance Evaluation of Piezo-Driven Synthetic Jet Devices
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作者 M. Chiatto L. de Luca 《World Journal of Engineering and Technology》 2016年第3期107-114,共9页
In the last two decades synthetic jet actuators have gained much interest among flow control techniques due to their short response time, high jet velocity and absence of traditional piping, that matches the requireme... In the last two decades synthetic jet actuators have gained much interest among flow control techniques due to their short response time, high jet velocity and absence of traditional piping, that matches the requirements of reduced size and low weight. A synthetic jet is generated by the diaphragm oscillation (generally driven by a piezo- electric element) in a relatively small cavity, producing periodic cavity pressure variations associated to cavity volume changes. The high pressure air exhausts through an orifice, converting membrane elastic energy in jet kinetic energy. This review paper faces the development of various lumped-element models (LEM) as practical tools to design and manufacturing actuators. LEM can predict quickly device performances such as frequency response in terms of membrane displacement, cavity pressure and jet velocity, as well as efficiency of energy conversion of input Joule power into useful kinetic power of air jet. Actuator performance is analyzed also by varying typical geometric parameters such as cavity height and orifice diameter and length, through a proper dimensionless form of the governing equations. 展开更多
关键词 synthetic jets Flow Control Lumped Element Model
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The Influence of Modulated Slotted Synthetic Jet on the Bypass of Hump
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作者 Petr Pick Miroslav Andrle Vladislav Saila Milan Matej ka 《Journal of Mechanics Engineering and Automation》 2014年第3期225-233,共9页
This paper deals with the influence of phase modulated synthetic jet on the aerodynamics of the hump in a closed test section Of the Eiffel-type wind tunnel. Three experimental methods of measurement techniques of thi... This paper deals with the influence of phase modulated synthetic jet on the aerodynamics of the hump in a closed test section Of the Eiffel-type wind tunnel. Three experimental methods of measurement techniques of this phenomenon were used: the pressure profile using the Kiel total pressure probe, the velocity profile using the CTA (constant temperature anemometry) probe and the visualization of the flow field using the hot film and the thermo camera, The experimental results with and without the influence of the synthetic jet were compared, as well the impact of the phase shift of the neighbouring synthetic jets. As a reference case, the flow around the hump without the influence of the synthetic jet was selected. The results of the measurement are presented in figures and compared. 展开更多
关键词 synthetic jet Kiel probe CTA probe loss coefficient phase shift modulation.
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Experimental study on shock interaction control of double wedge in high-enthalpy hypersonic flow subject to plasma synthetic jet
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作者 Xuzhen XIE Qiang LIU +6 位作者 Yan ZHOU Zhenbing LUO Wei XIE Guanghui BAI Kai LUO Qiu WANG Jianjun WU 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2024年第4期151-165,共15页
The hypersonic shock-shock interaction flow field at double-wedge geometries controlled by plasma synthetic jet actuator is experimentally studied in a Ma = 8 high-enthalpy shock tunnel with the purpose of exploring a... The hypersonic shock-shock interaction flow field at double-wedge geometries controlled by plasma synthetic jet actuator is experimentally studied in a Ma = 8 high-enthalpy shock tunnel with the purpose of exploring a novel technique for reducing surface heat flux in a real flight environment. The results demonstrate that increasing the discharge energy is advantageous in eliminating the shock wave, shifting the shock wave interaction point, and shortening the control response time. The oblique shock wave can be completely removed when the actuator's discharge energy grows from 0.4 J to 11.5 J, and the displacement of the shock wave interaction point increases by 124.56%, while the controlled response time is shortened by 30 μs. Besides, the reduction in diameter of the jet exit is firstly proved to have a negative impact on energy deposition in a working environment with incoming flow, which reduces the discharge energy and hence decreases the control effect. The shock wave control response time lengthens when the jet exits away from the second wedge. Along with comparing the change in wall heat flux at the second wedge over time, the control effect of plasma synthetic jet actuator with and without inflation is also analyzed. When plasma synthetic jet works in inflatable mode, both the ability to eliminate shock waves and the shifting effect of the shock wave interaction point are increased significantly, and the wall heat flux is also reduced. 展开更多
关键词 Hypersonic flow High-enthalpy flow Plasma synthetic jet Shock wave Flow control
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