1 RIFLED JET NOZZLE
TECHNICAL FIELD The invention concerns to jet engineering, namely to the jet nozzle construction used in drives of jet apparatuses, in particular of air, artillery, underwater free rockets and also individual mini- rockets.
BACKGROUND ART There is the nozzle of a jet engine containing confuser, mouth of the reduced cut, diffuser; ring flap adjusted to the back diffuser edge, forms its inlet with the selectively decreased cut for maintenance of hot gases stream separation stability from the diffuser wall in the first flight phase (patent of France #2705739, cl. F 02 K 9/97, 1994).
The mentioned nozzle is characterised by low tractive and power characteristics. Closest to the offered invention is the jet nozzle containing on an internal surface transversal ledges (the application of Germany # 4403469, cl. F 02 K 1/00, 1994). This nozzle also has low tractive and power characteristics. DISCLOSURE OF INVENTION
Problem of the invention is the improving tractive and power characteristics of the nozzle. The technical result - increase of specific impulse, rocket movement velocity increase, decrease of an aerodynamic or hydrodynamic resistance to rocket movement, increase of flying range and strike accuracy is reached by that the jet nozzle contains body with ledges on an internal surface, the ledges are located longitudinally and make in the nozzle cross-section the cogged form. One from lateral surfaces of each ledge is executed radial or concave. The ledges can have in the cross-section the form of an arc. The ledges also can be executed inside an insertion adjusted in the nozzle body.
The second variant of the offered jet nozzle contains body with ledges on an internal surface, the ledges have the form of a screw thread and make in the nozzle cross-section the cogged form.
One from lateral surfaces of the thread is executed radial or concave. The ledges in the cross-section can have the form of an arc. Besides the ledges can be executed inside an insertion adjusted in the nozzle body.
The offered device variants can be used both in subsonic and in supersonic nozzles of free rockets.
During the subsonic nozzle work the gas stream formed under fuel combustion, influences on ledges, adding to a rocket rotary movement round a centerline, that increases rocket stability in
flight in atmosphere or during its movement in a water and promotes flying range increase and strike accuracy. Herewith it is not necessary to adjust stabilisers which increase an aerodynamic or hydrodynamic resistance on magnitude from 1,5 up to 15 times and create effect of braking, decreasing of specific impulse magnitude and rocket velocity. During the supersonic nozzle work the rocket also acquires rotary movement round a centerline, besides stream supersonic gas extension shock waves create an additional force influencing on ledges and increasing of specific impulse magnitude i.e. the relation of draft to mass propellant consumption, and also rocket velocity.
BRIEF DESCRIPTION of DRAWINGS On Fig. 1 the longitudinal section of the first device variant is represented; on Fig. 2 - cross- section of the nozzle with one from lateral surfaces of each ledge executed radial; on Fig. 3 - cross- section of the nozzle with one from lateral surfaces of each ledge executed concave; on Fig. 4 - cross-section of the nozzle with a ledge in the form of an arc; on Fig. 5 - the longitudinal section of the offered device second variant with ledges in the form of a screw thread; on Fig. 6 - cross-section of the nozzle with one from lateral surfaces of a screw thread executed radial; on Fig. 7 - cross- section of the nozzle with one from lateral surfaces of a screw thread executed concave; on Fig. 8 - cross-section of the nozzle with ledges in the form of a screw thread having in the cross-section the form of an arc.
THE MODES FOR CARRING OUT THE INVENTION The first variant of the offered device concerns to the jet nozzle containing on an internal surface of body 1 ledges 2 which are located longitudinally and make in the cross-section of the nozzle the cogged form. One from lateral surfaces of each ledge 2 is executed radial 3 or concave 4. The ledges can also have in the cross-section the form of an arc 5.
The jet nozzle according to the second variant contains on an internal surface of body 1 ledges 6, which have the form of a screw thread and make in the cross-section of the nozzle the cogged form. One from lateral surfaces of a screw thread is executed radial 7 or concave 8. The ledges can have in the cross-section the form of an arc 9.
Both in first, and in the second variant of the invention the ledges can be executed both on an internal surface of body 1 and inside an insertion 10, adjusted in nozzle body 1. The mentioned insertion can be adjusted in rockets, which made earlier and have a smooth internal surface of the nozzle.
The adjustment of an insertion with ledges on usual rockets will allow to improve their
parameters: to increase specific impulse, movement velocity, flying range in atmosphere or during movement in a water, and strike accuracy.
During the subsonic nozzle work the gas stream formed under combustion of fuel influences ledges 2 or 6 and adds to a rocket rotary movement. During the supersonic nozzle work the stream supersonic gas extension shock waves create an additional force influencing on ledges 2 or 6.
The offered jet nozzle construction variants allow to increase a velocity of rocket movement up to 2 times, specific impulse up to 1,5 times, strike accuracy up to 1,8 times, decrease an aerodynamic or hydrodynamic resistance to rocket movement from 1,5 up to 15 times. INDUSTRIAL APPLICABILITY
The offered jet nozzle construction variants can be used in production of rockets, for example free rockets.
The free rockets of various purposes - anti-tank, air-defence, tactical and strategic - for a defeat of the ground, air and marine targets, are on arms motor-shooting, armoured, airborne, artillery, naval and air forces.
The air free rockets are used for a defeat of the air and ground targets. The free rockets of naval fleet are used for a defeat water-surface, coastal, underwater and also air targets.
The individual mini-rockets are intended for a defeat in near fighting of a manpower and easy armoured targets of the opponent. The equipment of free rockets by offered construction jet nozzles will increase combatability of all forces using the indicated rocket, by their movement velocity increase both in atmosphere and in a water, flying range and strike accuracy.