U.S. patent number 3,570,766 [Application Number 04/791,528] was granted by the patent office on 1971-03-16 for integral plug and strut nozzle.
This patent grant is currently assigned to THE United States of America as represented by the Secretary of the Navy. Invention is credited to Albert W. Johnson.
United States Patent |
3,570,766 |
Johnson |
March 16, 1971 |
INTEGRAL PLUG AND STRUT NOZZLE
Abstract
A one-piece exhaust nozzle for rocket motors. It is
substantially cylindrl with three funneled inlet holes at its
forward end, blending into a single opening at the aft end. A
center body, pyramid shaped, forms a contoured inner wall for the
nozzle which has a constantly expanding exhaust area.
Inventors: |
Johnson; Albert W. (Austin,
TX) |
Assignee: |
THE United States of America as
represented by the Secretary of the Navy (N/A)
|
Family
ID: |
25154022 |
Appl.
No.: |
04/791,528 |
Filed: |
January 15, 1969 |
Current U.S.
Class: |
239/265.11;
239/601 |
Current CPC
Class: |
F02K
9/97 (20130101) |
Current International
Class: |
F02K
9/00 (20060101); F02K 9/97 (20060101); B64d
033/04 () |
Field of
Search: |
;60/263,271
;239/265.11,265.15,422,428,433,601 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
Primary Examiner: King; Lloyd L.
Assistant Examiner: Love; John J.
Claims
I claim:
1. An integral exhaust nozzle for a rocket motor having a
cylindrical outer shape, three inlet openings formed in the forward
end of said nozzle to receive exhaust gases from said rocket motor,
three separate cone-shaped passages extending from said inlet
openings and intersecting to form a single terminal outlet in the
aft end of said nozzle where the exhaust gases are recombined, and
a substantially pyramid-shaped center body formed by the
intersection of said three cone-shaped passages.
2. An integral exhaust nozzle for a rocket motor according to claim
1 wherein the cones are elliptical.
Description
STATEMENT OF GOVERNMENT INTEREST
The invention defined herein may be manufactured and used by or for
the Government of the United States of America for governmental
purposes without the payment of any royalties thereon or
therefor.
BACKGROUND OF THE INVENTION
1. Field of the invention
This invention relates to a plug exhaust nozzle for a rocket motor
and more particularly to a nozzle where the exhaust gases are
received through three inlets and are recombined in the downstream
flow and discharged through a single aft opening.
2. Description of Prior Art
Heretofore annular exhaust nozzles have been formed of an outer
body and a center body, with the center body supported by crossbars
or tripodlike arms. These supports interfere with the flow of gases
and form crosscurrents in the exhaust which reduce the efficiency
of the motor. The inner contour of the nozzle is formed by inserts
which makes for leakage of exhaust gases and, by edge interference
of these inserts, causes crosscurrents in the flow.
SUMMARY OF THE INVENTION
A nozzle made in one piece, where the expansion of the gases is
controlled so that the explosion ratio to nozzle length is a
forward step. The integral molded nozzle is without the possibility
of gas leakage, while the form of intersecting elliptical cones
reduces the turbulence and provides greater efficiency.
An object of the present invention is to provide an exhaust nozzle
formed in one piece.
Another object of the present invention is to provide an exhaust
nozzle having a contoured inner and outer wall, integral, of
substantially cylindrical form and so controlling the flow of gases
as to prevent any leak path and provide a high thrust.
It is another object of the present invention to provide an
integral plug and strut nozzle, which for low temperature
propellants, could be molded from a carbon molding compound.
It is still another object of the present invention to provide an
integral plug and strut nozzle which may be manufactured at a
comparatively low cost.
It is still another object of the present invention to provide an
integral plug and strut nozzle which will provide the highest
expansion ratios with the shortest length.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention is illustrated in the accompanying drawing in
which:
FIG. 1 is a perspective view of the plug and strut nozzle;
FIG. 2 is a view looking at the aft end of the nozzle; and
FIG. 3 is a view looking at the forward end of the nozzle.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring to the drawings wherein like parts are designated by like
numbers, the integral plug and strut nozzle has a cylindrical outer
wall 12, a forward rim 13 and an aft rim 14.
The forward end of the nozzle receives the exhaust gases from the
motor and divides these gases to pass the gases through individual
distinct throats 15, 16 and 17. Sloping sidewalls 18, 19 and 21,
respectively, on the approach side of the throats funnel the gases
into the throats. The strut or center body 22 is shaped to
recombine the exhaust gases coming through the different throats
with the least turbulence. Gas flow from subsonic to supersonic is
only disturbed to the extent of flow over an airfoil. The shape of
the entire body is that of elliptical cones intersecting and
forming at their juncture, a strut or center body, the sides of
which are shaped to provide an airfoil construction over which the
gases flow.
The aft end of the nozzle is as though a plane was passed through
the intersecting cones, together with the strut at a point beyond
the apex of the strut. The arcs of the side of the cones 23, 24 and
25 serve as the outer extremity of the outer wall of the nozzle,
while the slopes of the strut or center body forms the inner wall
of the nozzle and as these slopes terminate in the apex 26, the
gases are progressively expanded in the shortest possible length of
nozzle.
The integral plug and strut nozzle of the present invention has
many advantages over the annular nozzle in use at present. It is
less expensive to manufacture. The thrust coefficient proves its
high efficiency. There is the highest expansion ratio in the
shortest length, the short length allowing a greater length of gain
and a consequent greater or longer flight of missile. For low
pressure and/or low temperature propellants, the entire nozzle
could be molded out of good graphite or carbon molding
compound.
* * * * *