Improved Means of Increasing the Speed of Ships by Reducing the Resistance to Propulsion.
Year: 1899

page_text: COMPLETE SPECIFICATION:
Improved Means of Increasing the Speed of Ships by Reducing the
Resistance to Propulsion.
I, JOSEF NEVKOVSKY, of Przemysl, Galacia, Austria, Lieutenant, do hereby
declare the nature of this invention and in what manner the same is to be per-
formed to be particularly described and ascertained in and by the following
statement:-
-
The object of the present invention is to diminish the resistance a ship meets
during its course through the water, by ejecting compressed air into the water
along the face of the hull of the vessel at suitable parts from the stem to the
stern thereof along its two sides so that the vessel slides as it were on a cushion
of air between it and the circumambient water. To attain such end, vessels
are fitted with compressors for air of suitable size and by means of which the
air is introduced under pressure into the water under and along the ship's surface,
the compressors driving the air into pipes leading to the places where it is
utilized,
:
On the accompanying drawings, are represented by way of example, some
forms of carrying out the invention, and on these drawings:-
Figures, 1, and 2, respectively represent in elevation and in plan view a system
of the air pipes vertically arranged;
Fig. 3, is a transverse section, on a larger scale, of the ship and showing one
of the vertical air tubes;
Fig. 4, shows a detail view, on a larger scale, of the air spouts ;
Figs. 5, and 6, are detail sections, respectively on the planes, A-B, and C-D,
of Fig. 4;
Fig. 7, represents a vertical section on E-F, Fig. 6;
Figs. 8, 9, 10, represent in longitudinal, transverse and horizontal section; the
application of the system with horizontal air pipes;
Figs. 11, and 12, show, in views at right angles to each other and on an enlarged
scale, an air outlet spout employed in the horizontal system represented in
Figs. 8, to 10; the nose being shown vertically instead of horizontally;
Fig. 13, shows a part of the keel of the vessel, the air pipe being in section
on the plane, G-H, Fig. 14;
Fig. 14, shows a side view of Fig. 13.
Figs. 15, 16, and 17, represent in three like views to Figs. 8, to 10, a vessel
provided with an air rose or sprayer in advance of the stem;
Fig. 18, shows a side view of the air sprayer;
Figs. 19, and 20, are vertical and horizontal sections of the sprayer, respectively
on the planes K-K, and J-J, Fig. 18; and
Figs. 21, and 22, represent, in side view, and transverse section on M-N,
Fig. 21, the air sprayer with the fore part of its sheet metal covering removed.
The air may be directed into the water by means of a vertical or horizontal
system of pipes. The vertical system is represented in Figs. 1, to 7, and is
characterized in that the air is introduced in large quantities principally towards
the stem, by pipes, 2, Fig. 1. Other pipes, 3, are arranged where the stem comes
into the median or side part of the hull of the vessel, whilst other pipes, 4, are
placed further back: the number of such pipes may be increased according to
requirements.

page_text: In the horizontal arrangement of the air outlet pipes (vide Figs. 8, to 14,) it
is a question especially of the arrangement of the pipes in the keel, and the
air feed from these pipes takes effect from the side of the stem; air conduits
may however be arranged at different places.
The air pipes are preferably arranged in grooves or channels formed in the
face of the hull of the ship, 5, 6, 7, 8, in Figs. 5, and 6, respectively, 21, 22,
23, 24, in Fig. 13, the channels, in shaped sheet metal, being secured to the
face of the vessel, which is grooved for this purpose, so that the air pipe can be
encased and secured by means of suitable bands or plates, not shown on the
drawings.
At the places where the air escapes from the pipe, the latter is slit longi-
tudinally, as at 11, 20, and at such points are arranged cylindrical coupling
boxes, 9, 18 (Figs. 6, 13,) which encircle the air pipes and act as escape channels
of the air into the water; the cylinders being so placed in the said channels,
at 6, 23, that the escaping air skims over the edge of the channel and along
the face of the hull, 5, 24, of the ship, without being impeded in its course.
Between the cylinders, 9, 18, respectively, the air pipe is provided with bands
or collars, 12, which can open on hinges, 13, (Fig. 5,) and are bolted together
at the flanges, 14, and serve, on the one hand, to clasp the air pipe, (which by
reason of its longitudinal slit.would otherwise be liable to be expanded by the
compressed air,) and, on the other hand, to maintain the spacing apart of the
cylinders and to cause the air to escape only by the openings, 10, 19, respectively.
The air may also be directed into the water by a rose or sprayer 16 applied in
advance of the stem at the extremity of a horizontally arranged air pipe, 15,
the rose allowing the jet of air to escape by openings. 17, 18, 19, 20, at its fore,
side and under faces, see Figs. 18, 19, 20. The pipe, 15, is arranged in a
suitable casing, 21-22, (Figs. 21, 22,) secured to the fore part of the hull and
protecting and strengthening this part of the stem, the casing being shaped to
offer a minimum resistance. Other pipes, 3, are or may be arranged at the
meeting of the stem and of the median part of the. hull, Fig. 15, as hereinbefore
described.
The quantity of air supplied to the different faces and places varies according
to the extent of surface to be treated from such place and also to the speed of
the vessel. The size of the air exits is not throughout the same, but increases
in proportion with their depth of immersion.
It is, of course, necessary to force the air into the water under a pressure
sufficient (say 5 atmospheres) to overcome the resistance it would meet, and for
this purpose air compressors of suitable power would require to be employed.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed, I declare that what
I claim is
The improved method of increasing the speed of ships, consisting in ejecting
highly compressed air into the water at suitable parts of and along the immersed
surface of the ship, and at the edge of the stem and in advance thereof by means
of air pipes and an air sprayer, as herein before described with reference to the 4
accompanying drawings.