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Featured Application: The present study can be used for the development of high-lift flow-control devices for future civil aircraft. To provide sufficient lift during takeoff and landing, large aircraft are equipped with complicated high-lift devices. The use of simple flaps coupled with active flow control (AFC) can achieve lift improvement while reducing mechanical structure and weight. The present study focuses on verifying the feasibility and effectiveness of simple flaps combined with sweeping jet flow control. An experimental study on the AFC of flaps, using sweeping jets, was carried out using a NASA SC(2)-0410 supercritical airfoil wind-tunnel model at Re = 2.0 × 105 (with velocity V = 10 m/s). In the experiment, the wing angle of attack (α) ranged from 3 to 18°, and the flap deflection angle (δ) ranged from 0 to 30°; the aerodynamic characteristics and surface pressure characteristics of the wing at typical working conditions were analyzed. Using sweeping jets to control the flow on the flaps, the momentum coefficients (for three actuator groups) of the jet are 0.8%, 3.6%, and 8.2%, respectively, and the maximum lift coefficient was increased by approximately 33%. The influence of the sweeping jet flow rate on the aerodynamic performance of the airfoil is analyzed. There are two main reasons for the lift coefficient increase caused by sweeping jet flow: an extra suction peak near the flap and a suction peak increase near the leading edge area caused by induced flow. [ABSTRACT FROM AUTHOR]

Combined blowing was performed on a Hybrid Wing Body (HWB) aircraft through wind tunnel testing at a Reynolds number of 1.75 × 106. The full cycle of separation and reattachment under the control of combined blowing was implemented using Computational Fluid Dynamics (CFD), and the mechanism of combined blowing inhibiting separation was analyzed. The aerodynamic characteristics of the baseline and the independent effects of the blown deflected trailing edge (TE), blown leading edge (LE), and combined blowing on the TE and LE were investigated. The results clearly show that combined blowing can inhibit the development of cross-flow, reduce the accumulation of a boundary layer at the tip, and inhibit the flow separation effect. The effect of using seamless simple flaps alone to increase the lift is limited; blowing control is required to enhance the lift further. Applying the blown deflected TE can improve the lift linear segment, so that 30° flap achieves the lift gain of 40° flap without control, while the drag coefficient is approximately 0.02 smaller, but the stall gradually advances. Using the blown LE can significantly increase the stall angle from 12° to 18°. However, the lift linear segment remains unaffected. In particular, combined blowing can achieve the control effect of improving the lift linear segment, delaying stall, and decreasing drag. Moreover, the maximum lift coefficient is approximately 0.19, and the lift-to-drag ratio increment in the control state with a 30° flap deflection angle is above 2.2 in the angle of attack range of 4° to 12° compared to the uncontrolled state with a 40° flap deflection angle. [ABSTRACT FROM AUTHOR]

In this work, to explore the control potential of reverse dual synthetic jets (RDSJs) in a flying wing aircraft (FWA), reverse dual synthetic jet actuators (RDSJAs) are integrated into a FWA with a hybrid flow mode of rollers and streamers. The aerodynamic characteristics and control mechanism are investigated using numerical simulations. The results show that the aerodynamic loads follow a nonlinear trend, and the overall process can be divided into three stages with an increasing angle of attack (AOA). In the first stage (AOA = 0°–8°), the RDSJs can improve the reverse pressure gradients and form alternate recirculation zones or even a large-area separation. The pressure rises before and falls after the exits, causing an increase in Cd and a drop in CL. The decrease in the leading-edge suction and the pressure envelope area results in a further increase with the increasing AOA, resulting in a reduction in ΔCL and an improvement in ΔCd. In the second stage (AOA = 8°–24°), the energy of the RDSJs is too low to form a strong disturbance over the leeward surface, and the promotion of favorable pressure gradients along the lower surface can weaken the control effects of the RDSJAs, causing a decrease in the narrowing degree of the pressure envelope. The leading-edge vortex (LEV) is weakened, and ΔCL increases as Cd experiences a drop. In the third stage (AOA = 24°–32°), the RDSJs interact with the larger separation and are capable of accelerating the flow over the wing section, elevating the longitudinal velocity of the LEV through entrainments and improving the strength and stability of the LEV. The accelerated flow creates negative pressures behind RDSJAs, causing a further reduction in the decrement of the pressure envelope area. An enhancement of CL and Cd appears under the influence of the above factors. [ABSTRACT FROM AUTHOR]

Wang Wanbo, a teacher at Henan University of Technology, interviewed to jiang Shengnan, a online writer, about Jiang Sheng men's series of historical novel creation motive, material selection, story structure, sex consciousness and narrative skills, style change, the similarities and differences between the online literature and traditional literature, online novel problems such as IP, marketization, commercialization have carried on the deep discussion, It tries to have a deep understanding and research on the way of jiang Shengnan's novel creation, the characteristics of his creation, the inner spiritual direction and value of the text. The creation of online literature is a mechanism through which authors, readers, platforms, and capital are jointly shaped. Media, capital, technology, and industry have brought great changes to the development of literature. Their intervention has deeply affected the prosperity, transformation and upgrading of online literature, and the creative activities of online authors have been affected accordingly. At the same time, Jiang Shengnan's creation has also enriched the "female-oriented" creation methods of online literature, and jointly constructed the "female novel" literary field with other female novels, and promoted the development of "her era" and "her economy" with the help of IP. [ABSTRACT FROM AUTHOR]