For the general case of a spatial isoenergetic flow of ideal gas,Helmholtz’s theorems are generalized and the speed with which vortex tubes move is found,keeping the intensity.It is shown that along the streamline wi...For the general case of a spatial isoenergetic flow of ideal gas,Helmholtz’s theorems are generalized and the speed with which vortex tubes move is found,keeping the intensity.It is shown that along the streamline without stagnation point,vorticity either is equal to zero everywhere,or it is non zero at all.The pattern of vortex lines behind the three-dimensional detached bow shock wave is specified.展开更多
According to the mechanism of the arc plasma heating effect,and from a phenomenological perspective of view,the plasma actuation was simplified as heating energy injected into the supersonic flow field for the numeric...According to the mechanism of the arc plasma heating effect,and from a phenomenological perspective of view,the plasma actuation was simplified as heating energy injected into the supersonic flow field for the numerical research on controlling detached shock of the blunt body in non-center symmetrical positions.Besides,experimental research on the form and strength of detached shock wave control by plasma aerodynamic actuation in non-center symmetrical positions was conducted in a high-speed shock tunnel(M=2).The results showed that the detached distance of shock wave increased and the strength of normal shock wave ahead of the detached shock wave reduced when plasma actuation was applied.The control effect was greatly improved after the magnetic field was applied and the effect of upwind-direction flow was the best one.When the upwind-direction flow was applied with 1000 V voltage actuation,the distance of detached shock wave would increase from 3.4 to 7.6 mm and the time average strength of normal shock wave was weaken by 5.5%.At last,the mechanism of plasma actuation on controlling the detached shock wave was briefly analyzed.展开更多
文摘For the general case of a spatial isoenergetic flow of ideal gas,Helmholtz’s theorems are generalized and the speed with which vortex tubes move is found,keeping the intensity.It is shown that along the streamline without stagnation point,vorticity either is equal to zero everywhere,or it is non zero at all.The pattern of vortex lines behind the three-dimensional detached bow shock wave is specified.
基金supported by the National Natural Science Foundation of China (Grant Nos. 51276197,51207169)
文摘According to the mechanism of the arc plasma heating effect,and from a phenomenological perspective of view,the plasma actuation was simplified as heating energy injected into the supersonic flow field for the numerical research on controlling detached shock of the blunt body in non-center symmetrical positions.Besides,experimental research on the form and strength of detached shock wave control by plasma aerodynamic actuation in non-center symmetrical positions was conducted in a high-speed shock tunnel(M=2).The results showed that the detached distance of shock wave increased and the strength of normal shock wave ahead of the detached shock wave reduced when plasma actuation was applied.The control effect was greatly improved after the magnetic field was applied and the effect of upwind-direction flow was the best one.When the upwind-direction flow was applied with 1000 V voltage actuation,the distance of detached shock wave would increase from 3.4 to 7.6 mm and the time average strength of normal shock wave was weaken by 5.5%.At last,the mechanism of plasma actuation on controlling the detached shock wave was briefly analyzed.
