The actuations generated by the plasma synthetic jet actuator (PSJA) may become weak under multiple pulses when discharge frequency increases. In order to further study characteristics of actuations, high-speed Schlieren method is adopted for experimental on a nanosecond (NS-PSJA) made machinable ceramic. Three typical working states are captured numbers measurements, which continuous, critical, and discontinuous states. For deep understanding, relationship between NS-PSJA discussed in two...

Plasma synthetic jets (PSJs) have received widespread attention because of their rapid response capability. The use PSJ shock and thermal effects for active flow control has been investigated in many recent studies. Through numerical simulation, this study found that the geometric position a actuator on an airfoil surface is key factor affecting effects. Different positions different lift-drag characteristics airfoil, mechanism components. can be divided into three types: effect, coupling...

Abstract In the process of mechanized production mulberry, falling collision damage is one main forms, which causes serious and accelerates fruit decay. Through drop test simulation analysis mulberry fruit, relationship between conditions degree was established, so as to provide reference for reducing damage. The carried out. factors indicators established. height, plate angle, material, direction were taken factors, then energy loss selected indicator. analyzed by numerical simulation,...

Abstract During the mechanized production and processing of mulberry, fresh fruit can experience serious mechanical damage. In this study, compression tests were conducted to investigate effect different parameters on damage mulberry. The results showed that extent was mainly influenced by loading displacement rate applied during compression; increased with increasing displacement. At an initial moisture content 86.76%, indentation area ratio from 0.0725 0.2756 when 3.0 6.0 mm. Nuclear...

The present study investigates the discharge and flow characteristics of a sliding (SD) driven by alternating current (AC) negative direct (DC) high voltage in continuous operation burst-mode actuation quiescent air. burst frequency f is set at 20, 40, 50, 100 Hz with duty cycle τ fixed 50%. Different cases exhibit similar morphologies electrical properties. results indicate that induced horizontal body force generated SD undergoes following stages: formation, intensification, accumulation,...

Jet flow-control technology is a promising area of fluid research. In this work, the effect curved-surface jet in an incoming flow Mach = 5 and its underlying control mechanism are experimentally studied using high-speed photography dynamic force measurement. From establishment complete stability field, evolutionary process can be roughly divided into five stages: two equilibrium stages (short long term), acceleration stage, bow shock formation interference removal stable state. By defining...

Dielectric barrier discharge (DBD) plasma is one of most promising flow control method for its several advantages. The present work investigates the authority nanosecond pulse DBD actuators on a flying wing model's aerodynamic characteristics. forces and moments are studied by means experiment numerical simulation. simulation results in good agreement with results. Both indicate that NS-DBD have negligible effect moment at angles attack smaller than 16°. However, significant changes can be...

Abstract Corn cobs were fermented with Aspergillus niger to produce the high-quality soluble dietary fiber (SDF) excellent food safety. In this work, fermentation process was optimized by single-factor test and response surface methodology (RSM) determine conditions (material-liquid ratio 1:30, inoculum concentration 11%, temperature 32 ℃, time 6 d, shaking speed 200 r/min), SDF yield of corn cob increased from 2.34–11.92% SDF/TDF reached 19.08%, achieving requirements (SDF/TDF more than...

The behavior of a nanosecond pulsed sliding discharge plasma actuator with the ambient pressure from 27 to 101 kPa is experimentally investigated. electric characteristics, morphologies, and surface temperature distribution supplied by constant voltages are studied under different conditions. threshold for establishment 54–75 in this paper. results show that positive peak value current tends increase as decreases. Time-integrated images indicate luminosity uniformity enhanced low-pressure...

Sliding discharge, as a new type of electrical is being gradually applied in plasma active flow control recent years. In this work, the particle image velocimetry (PIV) experiments were conducted to investigate airflow characteristics induced by sliding discharge actuator at varied voltage signals. The results show that integral thrust produced negative alternating current (AC) power stronger than normal AC under same magnitude. direction changes along with changing two Furthermore, angle...

Dielectric barrier discharge (DBD) has been one of the most promising techniques for flow control, but practical application needs a large plasma surface. A three-electrode sliding actuator (SDPA) can generate filling inter-electrode distance. In this study, performance an SDPA flight at low pressures is reported. When pressure decreases, becomes more intensive. Current peaks and power consumption electrode 1 become higher pressure. Sliding fully developed 54 kPa, morphology resembles...

Due to size limitations and the working environment near ground, small low-altitude unmanned aerial vehicles (UAVs) cannot carry large-area solar cells energy storage devices. Solar alone has only a limited effect on improvement of their endurance. To solve this problem, study proposes combination technology dynamic soaring improve endurance UAVs. Then, optimal acquisition strategy based is analyzed in terms energy. The motion equations consumption models UAV horizontal wind shear are...

The plasma produced by pulsed surface arc discharge conducts heat and mass transfer in the form of convection. This process has an important influence on engineering application plasma. study experimentally investigated dynamic processes transfer. results show that mode convection clusters will change during And Richard numbers are different stages. Plasma from forced initial stage to natural final stage. released gas accumulated space temperature difference, thereby affecting paper...