Numerical investigation of improving the performance of a single expansion ramp nozzle at off-design conditions by secondary injection

Effect of a Secondary Injection on the Performance of Three-Dimensional Over-under TBCC Exhaust Nozzles

“…The entire inner wall of the exhaust nozzle was taken to be the control body for convenience. According to the law of conservation of momentum in an open system, the outlet excess impulse in the x-direction can be expressed as the difference between the inlet xdirection impulse and the x-direction component relating to the relative pressure and viscous force integral on the inner wall (Lv et al 2017b). The excess impulse in the x-direction at the outlet of the exhaust nozzle can be solved using the following equation： ( )…”

“…Flow control techniques offer various active and passive flow control measures (Gronland and Berens 1995;Asbury et al 1996;Tsunoda et al 2000;Gamble and Haid 2004;Hao and Wang 2009;Zhou et al 2016;Zhou and Wang 2019), with secondary injection and synthetic jet actuators (SJA) being the most-used active measures. Lv et al (2017b) performed numerical simulations using a two-dimensional (2D) SERN model with cowl-based secondary injection. They explored the impact of different secondary injection parameters on exhaust nozzle performance and found that secondary injection can increase the thrust coefficient, lift and pitch moment of overexpanded SERNs by 3.16%, 29.43%, and 41.67%, respectively.…”

Research Progress on Active Secondary Jet Technology in Supersonic Flow Field of Aerospace Propulsion Systems

“…The distribution of components in the flow field after in tion is shown in Figure 33. In the same year, Lv [144] aimed to increase the performance of the nozzle used wide-speed range aircraft engine and prevent thrust loss caused by overexpansion. T discovered that inducing separation in the straight edge of the nozzle during jet inject is an effective method.…”

“…The results are shown in Figure 34, wh indicated that as the secondary flow pressure ratio increased, both the zenith angle ra and the azimuth angle range showed a decreasing trend in total radiation intensity, w maximum decreases of 14.49% and 16.38%, respectively. In the same year, Lv [144] aimed to increase the performance of the nozzle used in wide-speed range aircraft engine and prevent thrust loss caused by overexpansion. They discovered that inducing separation in the straight edge of the nozzle during jet injection is an effective method.…”