To improve the comfortability and safety of aircraft,the demand of rectangular submerged inlets(RSIs)with low resistance is proposed to increase the inlet flow rate of ram air. A theoretical model is built to numerica...To improve the comfortability and safety of aircraft,the demand of rectangular submerged inlets(RSIs)with low resistance is proposed to increase the inlet flow rate of ram air. A theoretical model is built to numerically analyze the effects of geometric parameters on the inlet mass flow rate of RSIs. The geometric parameters in question here encompass the aspect ratio of 2—4,the ramp angle of 6°—7°,the characteristic parameter of the throat of 0.20 —0.30,the ramp length of 939—1 337 mm,and the cone angle of 0° —3°. Simulation results demonstrate that the mass flow rate(MFR)is positively correlated with the aspect ratio,ramp angle,ramp length,and cone angle,and negatively correlated with characteristic parameter of the throat. Within the range of the geometric parameters considered,the RSI with the aspect ratio of 3,the ramp angle of 6°,the characteristic parameter of the throat of 0.20,the ramp length of 1 337 mm,and the cone angle of 3° obtains the largest MFR value of about 2.251 kg/s.展开更多
Based on the phenomenon of"split brick by Qigong",a mechanical model for short beam impact is proposed.Combined with the traditional energy method,a theoretical analysis of the impact of the short beam(Timos...Based on the phenomenon of"split brick by Qigong",a mechanical model for short beam impact is proposed.Combined with the traditional energy method,a theoretical analysis of the impact of the short beam(Timoshenko beam)closer to the real situation is made considering the quality and initial deformation.The optimal solution of short beam impact problem of how to choose the position where the short beam is most likely to break is obtained.The finite element numerical analysis and experimental test are used,and the results verify the applicability of the theoretical analysis of the proposed model.展开更多
基金supported by the Open Project of Key Laboratory of Aircraft Environment Control and Life Support,MIIT(No.KLAECLS-E-202001)。
文摘To improve the comfortability and safety of aircraft,the demand of rectangular submerged inlets(RSIs)with low resistance is proposed to increase the inlet flow rate of ram air. A theoretical model is built to numerically analyze the effects of geometric parameters on the inlet mass flow rate of RSIs. The geometric parameters in question here encompass the aspect ratio of 2—4,the ramp angle of 6°—7°,the characteristic parameter of the throat of 0.20 —0.30,the ramp length of 939—1 337 mm,and the cone angle of 0° —3°. Simulation results demonstrate that the mass flow rate(MFR)is positively correlated with the aspect ratio,ramp angle,ramp length,and cone angle,and negatively correlated with characteristic parameter of the throat. Within the range of the geometric parameters considered,the RSI with the aspect ratio of 3,the ramp angle of 6°,the characteristic parameter of the throat of 0.20,the ramp length of 1 337 mm,and the cone angle of 3° obtains the largest MFR value of about 2.251 kg/s.
基金supported in part by the National College Students Innovation Training Program
文摘Based on the phenomenon of"split brick by Qigong",a mechanical model for short beam impact is proposed.Combined with the traditional energy method,a theoretical analysis of the impact of the short beam(Timoshenko beam)closer to the real situation is made considering the quality and initial deformation.The optimal solution of short beam impact problem of how to choose the position where the short beam is most likely to break is obtained.The finite element numerical analysis and experimental test are used,and the results verify the applicability of the theoretical analysis of the proposed model.
