Plasma-based experimental investigation of double compression ramp shock wave/boundary layer interaction control

Abstract

An experimental investigation on the control effects of the high-frequency streamwise pulsed arc discharge array (HS-PADA) on the double compression ramp shock wave/boundary layer interaction (DCR-SWBLI) was carried out at Mach 2.0. Firstly, two types of ramp configurations were designed. The base flow field and actuation flow field were investigated. The actuation frequencies were 10 kHz and 20 kHz. Fast Fourier transform and root-mean-square methods were applied based on schlieren images. The base flow field indicated that the compression effect of ramps decreased with the lengthen of the first ramp. The results of actuation flow field showed that the 20 kHz actuation was superior to the 10 kHz actuation in weakening the shock wave intensity. The HS-PADA exhibited two types of control effects: modifying the shock structure, which was closely related to the separation zone, and modifying the low-frequency unsteadiness of the shock wave, which might not be related to the separation zone. The first separation shock wave, of which the high-frequency motion was more intense under actuation, may be more sensitive to HS-PADA than the second. Finally, the control mechanism of the HS-PADA on DCR-SWBLI was extracted.

Experimental Investigation on the Control of Hypersonic Shock Wave/Boundary Layer Interaction Using Surface Arc Plasma Actuators at Double Compression Corner

“…Firstly, schlieren measurements of a Ma = 6.0 noise flow field and quiet flow field are carried out. Compared with a Ma = 2.0 incoming flow condition [13], the corner leading edge under hypersonic conditions has a larger separation region. Figure 5a shows the instantaneous schlieren image under the noise flow field.…”

“…Tong et al [12] conducted a direct numerical simulation of a double compression corner with Mach number 2.9, the angle of the two stages was fixed at 12 • and 24 • , respectively, and studied the influence of the flow direction length L c of the first stage on the flow field structure. It was found that with the increase in L c , the size of the separation region is significantly reduced, the width of the Görtler vortex is reduced, and the directional coherence is enhanced [13][14][15].…”

Experimental Study on Hypersonic Double-Wedge Induced Flow Based on Plasma Active Actuation Array

“…Based on the time-resolved schlieren space gray image, this paper also analyzes the decomposition through root mean square (RMS) and Snapshot proper orthogonal decomposition (SPOD). Although schlieren display technology is mainly used for qualitative flow field diagnosis, some post-processing methods based on schlieren snapshot sequences have also been developed rapidly in recent years, which are used to extract semi-quantitative data from a large number of qualitative schlieren data and then initially reveal some quantitative flow field results [23]. In this paper, in addition to analyzing the instantaneous schlieren results, statistical processing is performed on the obtained schlieren image sequence to obtain its average schlieren intensity field (I mean ) and RMS schlieren intensity field (I rms ), which are specifically defined as follows:…”

Aerodynamic Instabilities in High-Speed Air Intakes and Their Role in Propulsion System Integration

“…More recently, Liu et al [156] investigated the effects of steady and pulsed discharge arcs on flow control, demonstrating that the steady streamwise arcs reduced the oblique shock strength by about 4%, leading to the upstream movement of the shock, while the pulsed discharge had little effect on the shock control. Zhao et al [157] used a high-frequency streamwise pulsed arc discharge array on a double compression ramp and found that high-frequency injection is more effective at weakening the shock intensity and the high-frequency motion of the unsteady shockwave. The plasma deposition method may show promising results in controlling the flow at some transient regimes encountered in off-design conditions, but the feasibility of practical implementation still remains in question.…”