Method for increasing the range of spin-stabilized projectiles, and projectile of said type
AssigneeAlpha Velorum AG
InventorMartin Ziegler
Life of this patent
Estimating the term…
Abstract
To increase the range of a spin-stabilized projectile which moves in a surrounding medium, the surrounding medium from a stagnant-water region of the projectile is, by means of a part of the rotational energy of the projectile, conveyed under the inflowing boundary layer at the outer surface of the projectile, and thus the speed gradient of the boundary layer in the vicinity of the wall is reduced. For this purpose, the outer surface has at least one encircling groove (9) which is connected by radial transverse ducts (10) to at least one longitudinal duct (11) in the interior of the projectile, which in turn is connected to an opening in the rear of the projectile.
Claims15
A method for increasing a range of a spin-stabilized projectile moving in a surrounding medium, wherein the surrounding medium is conveyed from a stagnation area of the spin-stabilized projectile by a rotational energy of the spin-stabilized projectile under an inflowing boundary layer at an outer surface of the spin-stabilized projectile and a speed gradient of the inflowing boundary layer proximate to the outer surface of the spin-stabilized projectile is therefore lowered, the method comprising:
- (A) pumping of a fluid by centrifugal forces from a front end of at least one longitudinal channel inside the spin-stabilized projectile through radial channels into at least one encircling groove reservoir to spread the fluid around a circumference of the spin-stabilized projectile, and then feeding the fluid along a sloped back face of the encircling groove reservoir into the inflowing boundary layer while pumping energy originates from the rotational energy of the spin-stabilized projectile;
- followed by
- (B) transportating the fluid towards a tail of the spin-stabilized projectile and the stagnation area by shear forces within the inflowing boundary layer;
- followed by
- (C) collecting the fluid in the stagnation area by a base drag pressure gradient behind the tail of the spin-stabilized projectile;
- and followed by
- (D) longitudinally transporting the fluid from the stagnation area through the at least one longitudinal channel towards the front end of the at least one longitudinal channel by a longitudinal pressure gradient caused by the pumping of step A.
A spin-stabilized projectile comprising:
- an outer surface;
- a projectile tip;
- and
- a projectile tail, wherein the outer surface has at least one encircling groove that permanently opens to the a surrounding medium and is connected by radial transverse channels to at least one longitudinal channel inside the spin-stabilized projectile, the at least one longitudinal channel is connected to an opening in the projectile tail during a complete flight.
A spin-stabilized projectile, comprising:
- an outer surface;
- a projectile tip;
- and
- a projectile tail, wherein the outer surface has at least one encircling groove permanently open to a surrounding medium that is connected by radial transverse channels to at least one longitudinal channel inside the spin-stabilized projectile, the at least one longitudinal channel is connected to an opening in the projectile tail during a complete flight, and a radial distance between an entry and an exit of each of the radial transverse channels is at least one-third of a diameter of the spin-stabilized projectile.
Dependencies are inferred from the claim text.