Numerical Analysis of the Interference Effect of Oblique Forward Jet on the Rear Body of Aircraft in Extreme Environments

The oblique forward jet from the rear body serves as an effective mechanism for achieving rapid separation between the front and rear stages of an aircraft.However，it is susceptible to significant interference with the aircraft's flow field，particularly under extreme environmental conditions.This study employed numerical simulations to investigate the unique interference flow patterns between the oblique forward jet of the rear body and the incoming flow，under a combination of extreme conditions such as low pressure，high Mach number，and a high jet pressure ratio (on the order of 10⁴) at the rear body.The research specifically analyzed the impact of the angle of attack (ranging from 0° to 10°) on the flow field structure and aerodynamic performance of the aircraft during the oblique forward jet operation from the rear body.Findings reveal that on the windward side，the height of the bow shock，the barrel shock，and the separation length decrease monotonically as the angle of attack increases.However，these values tend to stabilize and show little change beyond a 6° angle of attack.Conversely，on the leeward side，these parameters increase monotonically with the angle of attack.The width of the bow shock decreases monotonically on the windward side with increasing angle of attack，while on the leeward side，it remains largely unaffected by changes in the angle of attack.The oblique forward jet from the aircraft's rear body creates a large-scale flow interference zone that extends to the head position of the front body.This phenomenon reduces the influence of the incoming flow on the front body，thereby diminishing the effect of the angle of attack on the front body's aerodynamic performance.Simultaneously，complex flow field structures，such as bow shocks and barrel shocks generated by the oblique forward jet at the rear body，actually amplify the impact of the angle of attack on the aerodynamic performance of the rear body.The study concludes that at lower angles of attack (0° to 2°)，jet interference is more conducive to inter-stage separation.