초록 ▼

A shock wave in a gas is modified by emitting energy to form an extended path in the gas; heating gas along the path to form a volume of heated gas expanding outwardly from the path; and directing a path. The volume of heated gas passes through the shock wave and modifies the shock wave. This elimin

A shock wave in a gas is modified by emitting energy to form an extended path in the gas; heating gas along the path to form a volume of heated gas expanding outwardly from the path; and directing a path. The volume of heated gas passes through the shock wave and modifies the shock wave. This eliminates or reduces a pressure difference between gas on opposite sides of the shock wave. Electromagnetic, microwaves and/or electric discharge can be used to heat the gas along the path. This application has uses in reducing the drag on a body passing through the gas, noise reduction, controlling amount of gas into a propulsion system, and steering a body through the gas. An apparatus is also disclosed.

대표청구항 ▼

1. A method of controlling flow in a gas, comprising the steps of: ionizing a region of gas, using one or more laser pulses;heating said ionized region of gas, using one or more microwave pulses, to form a volume of heated gas expanding outwardly from the region; anddirecting said ionized region and

1. A method of controlling flow in a gas, comprising the steps of: ionizing a region of gas, using one or more laser pulses;heating said ionized region of gas, using one or more microwave pulses, to form a volume of heated gas expanding outwardly from the region; anddirecting said ionized region and heated volume by directing said laser and microwave pulses. 2. The method according to claim 1, in which said flow control is used to modify forces on a body traversing said gas. 3. The method according to claim 2, in which said ionized region is generated at the surface of said body. 4. The method according to claim 2, in which said ionized region is generated in front of said body. 5. The method according to claim 2, in which said ionized region is generated in the flow field contributing to the forces on said body. 6. The method according to claim 2, in which said laser and microwave pulses are directed from off of said body. 7. The method according to claim 2, in which laser pulses form arrays of confining laser filaments to better guide and contain said microwave pulses. 8. The method according to claim 2, in which said laser and microwave pulses are directed from said body. 9. The method according to claim 2, in which said body is a projectile. 10. The method according to claim 2, in which said body is a vehicle. 11. A method of exerting control forces on a body traversing a gas, comprising the steps of: ionizing a region of gas in the flow field contributing to the forces on said body, using one or more laser pulses;heating said ionized region of gas, using one or more microwave pulses, to form a volume of heated gas expanding outwardly from the region; anddirecting said ionized region and heated volume by directing said laser and microwave pulses. 12. The method according to claim 11, in which said laser pulses ionize said region of gas by generating ionization at the body surface. 13. The method according to claim 12, in which said laser pulses are nanosecond laser pulses. 14. The method according to claim 12, in which said laser pulses are directed from off of the body. 15. The method according to claim 11, in which laser pulses form arrays of confining laser filaments to better guide and contain said microwave pulses. 16. A method of exerting and/or modifying forces on a body traversing a gas, comprising the steps of: ionizing a region of gas in the flow field contributing to the forces on said body, using one or more laser pulses which are directed from the body;heating said ionized region of gas, using one or more microwave pulses which are directed from the body, to form a volume of heated gas expanding outwardly from said region; anddirecting said ionized region and heated volume by directing said laser and microwave pulses. 17. The method according to claim 16, in which said laser pulses are filamenting laser pulses, ionizing gas off of the body. 18. The method according to claim 17, in which the effect on the body is to reduce drag and/or improve vehicle performance. 19. The method according to claim 16, in which said laser pulses create ionization at the surface of the body. 20. The method according to claim 19, in which the effect on the body is to reduce drag and/or improve vehicle performance.