U.S. patent application number 12/942458 was filed with the patent office on 2012-05-10 for air cavity vessel having longitudinal and transverse partitions.
This patent application is currently assigned to HYUNDAI HEAVY INDUSTRIES CO., LTD.. Invention is credited to Seok-Cheon GO, Hong-Gi LEE, Keh-Sik MIN.
Application Number | 20120111258 12/942458 |
Document ID | / |
Family ID | 45990723 |
Filed Date | 2012-05-10 |
United States Patent
Application |
20120111258 |
Kind Code |
A1 |
MIN; Keh-Sik ; et
al. |
May 10, 2012 |
AIR CAVITY VESSEL HAVING LONGITUDINAL AND TRANSVERSE PARTITIONS
Abstract
An air cavity vessel having longitudinal and transverse
partitions is provided. The air cavity vessel, which injects air
into the bottom thereof to form air layers in order to reduce
resistance of the vessel, includes transverse partitions
partitioning the bottom in a transverse direction, longitudinal
partitions partitioning the bottom in a longitudinal direction,
spatial areas defined in a grid pattern by the transverse
partitions and the longitudinal partitions, an air supply unit
installed in a forebody of the vessel and supplying compressed air
into the spatial areas, and a compressor for supplying the
compressed air to the air supply unit. Thereby, multiple air layers
are formed on a bottom flat area on a small scale.
Inventors: |
MIN; Keh-Sik; (Seoul,
KR) ; GO; Seok-Cheon; (Ulsan, KR) ; LEE;
Hong-Gi; (Ulsan, KR) |
Assignee: |
HYUNDAI HEAVY INDUSTRIES CO.,
LTD.
Ulsan
KR
|
Family ID: |
45990723 |
Appl. No.: |
12/942458 |
Filed: |
November 9, 2010 |
Current U.S.
Class: |
114/289 |
Current CPC
Class: |
Y02T 70/122 20130101;
Y02T 70/10 20130101; B63B 1/38 20130101 |
Class at
Publication: |
114/289 |
International
Class: |
B63B 1/38 20060101
B63B001/38 |
Claims
1. An air cavity vessel in which air is injected into a bottom
thereof to form an air layer, the air cavity vessel comprising:
transverse partitions that are installed on a bottom of a recess
formed in a bottom portion of the vessel to partition the bottom
portion of the vessel in a transverse direction; longitudinal
partitions that are installed on the bottom of the recess formed in
the bottom portion of the vessel to partition the bottom portion of
the vessel in a longitudinal direction; spatial areas that are
defined in a grid pattern by the transverse partitions and the
longitudinal partitions; a hydraulic actuator that adjusts a height
of at least one of the transverse partitions and the longitudinal
partitions corresponding to a thickness of an air layer formed in
the bottom portion of the vessel; an air supply unit that is
installed in a forebody of the vessel and supplies compressed air
into the spatial areas, an amount of the compressed air supplied
into the spatial areas being controlled by a hydraulic part of the
air supply unit; and means for supplying the compressed air to the
air supply unit, wherein the air layer is formed in multiple parts
on the bottom portion of the vessel.
2. The air cavity vessel as set forth in claim 1, wherein the
longitudinal and transverse partitions installed to have the grid
pattern include at least one air flow hole formed thereon, which
enables the spatial areas to communicate with each other such that
the compressed air flows between the spatial areas.
3. The air cavity vessel as set forth in claim 2, wherein the air
flow hole is formed at a half height of the longitudinal or
transverse partition from a lower end of the longitudinal or
transverse partition.
4. The air cavity vessel as set forth in claim 1, wherein the air
supply unit includes an air chamber formed to communicate with the
air supplying means, a nozzle hinged to a fore of the bottom of the
vessel to be located at an end of the air chamber, and the
hydraulic part installed in the vessel to be connected with the
nozzle and drive the nozzle around a hinge.
5. The air cavity vessel as set forth in claim 1, wherein the
recess is formed such that opposite edges thereof are inclined to
form an angle relative to a vertical axis of the vessel.
Description
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates, in general, to an air cavity
vessel having longitudinal and transverse partitions and, more
particularly, to an air cavity vessel having longitudinal and
transverse partitions, in which the longitudinal and transverse
partitions are formed on a flat bottom area in a grid pattern, and
spatial areas defined by the longitudinal and transverse partitions
are supplied with air so as to form multiple air layers on a small
scale.
[0003] 2. Description of the Related Art
[0004] A well-known type of air cavity vessels employs technology
that reduces the resistance to water by i.e. injecting air into a
flat bottom area to thereby form air layers and reduce a submerged
surface area of the hull.
[0005] One of such air cavity vessels is known from U.S. Pat. No.
3,595,191, in which a bottom of a hull of a seagoing vessel such as
an oil tanker is provided with a plurality of downward open type
air cavities. Thereby, the submerged surface area of the hull is
reduced, so that hydrodynamic characteristics such as resistance to
water are improved.
[0006] Further, Netherlands Patent No. 9301476 discloses a vessel
in which air cavities into which air is injected are formed in a
bottom area of the hull. Due to a decrease in the friction between
an air layer in the cavity and water passing through the hull, the
resistance to water is reduced, so that the consumption of fuel is
cut back on to permit more economical propulsion.
[0007] However, these known vessels can be used only for flat
water. In detail, since air leaks out of the downward open type air
cavity when the vessel is rocked and tossed while sailing, the air
cavity fails to properly exert its function, and causes the high
resistance of the vessel to increase the consumption of fuel, so
that the vessel is uneconomically propelled.
[0008] Meanwhile, the vessel is propelled by the propeller that is
located underwater. The propeller is adversely affected by air
arriving from the cavity. This reduces a lift force of propeller
blades to make a thrust force and torque unstable or eliminate a
thrust force.
[0009] To solve such a problem in the conventional air cavity
vessel, PCT/NL2007/050242 discloses another air cavity vessel,
which includes a hull that has a stern, bow and bottom, an air
cavity that is formed at the bottom of the hull and includes a
cavity top surface, a front wall, and a front section located
nearest to the bow, and an air inlet that is located in the air
cavity. Here, the vessel includes a wave deflector defining a lower
surface which is situated in the front section of the air cavity
and at a distance from the cavity top surface and extends from the
front wall substantially in the direction of the stern. In the air
cavity vessel, the wave deflector should be separately installed,
and thus has an influence on the overall design structure of the
entire vessel.
SUMMARY OF THE INVENTION
[0010] Accordingly, the present invention has been made keeping in
mind the above problems occurring in the related art, and an object
of the present invention provides an air cavity vessel having
longitudinal and transverse partitions, in which the longitudinal
and transverse partitions are formed at the bottom of a large
vessel in a grid pattern, and small-scale multiple air layers are
defined by spatial areas formed by the longitudinal and transverse
partitions.
[0011] Another object of the present invention provides an air
cavity vessel having longitudinal and transverse partitions, in
which air is prevented from leaking out of air layers of the bottom
of the vessel toward the vessel by small-scale multiple air layers
while the vessel is moving (rolling and pitching) on the waves.
[0012] Another object of the present invention provides an air
cavity vessel having longitudinal and transverse partitions, in
which air is injected from the fore of the vessel into a recess
formed in the bottom of the vessel, and an air layer is divided
into multiple small parts by the longitudinal and transverse
partitions, thereby promoting stable formation of the air layers of
the bottom of the vessel, and thus maximizing an effect of reducing
resistance. These small-scale multiple air layers relatively
increases a surface tensile force, one of the air layer formation
mechanisms, when actually applied to a large vessel, thereby
helping to form stable air layers.
[0013] Another object of the present invention provides an air
cavity vessel having longitudinal and transverse partitions, in
which edges of the recess of a bottom of the vessel are formed in a
shape inclined at a predetermined angle rather than in a
perpendicular shape, thereby preventing lateral leakage of the air
layers of the bottom of the vessel when the vessel rolls.
[0014] Another object of the present invention provides an air
cavity vessel having longitudinal and transverse partitions, in
which air flow holes are formed in the longitudinal and transverse
partitions, and air flows from an air supply unit installed at the
fore of the bottom of the vessel in order to form small-scale
multiple air layers, thereby making it possible to simplify an air
supply system and to facilitate pressure equilibrium in the air
layers.
[0015] Another object of the present invention provides an air
cavity vessel having longitudinal and transverse partitions, in
which an air flow hole is formed apart from a lower end of each of
the longitudinal and transverse partitions by a predetermined
distance, thereby making it possible for compressed air to flow
into spatial areas when the vessel is moving (rolling and pitching)
on the waves.
[0016] Another object of the present invention provides an air
cavity vessel having longitudinal and transverse partitions, in
which a height of each transverse partition is adjusted within a
range less than the height of a recess formed in the bottom of the
vessel, thereby making it possible to additionally reduce
resistance under the conditions in which the vessel is placed when
it is actually moving.
[0017] According to one aspect of the present invention, there is
provided an air cavity vessel in which air is injected into a
bottom thereof to form air layers in order to reduce the resistance
thereof. The air cavity vessel includes: transverse partitions
partitioning a bottom of the vessel in a transverse direction;
longitudinal partitions partitioning the bottom of the vessel in a
longitudinal direction; spatial areas that are defined in a grid
pattern by the transverse partitions and the longitudinal
partitions; an air supply unit that is installed in a forebody of
the vessel and supplies compressed air into the spatial areas; and
means for supplying the compressed air to the air supply unit,
wherein multiple air layers are formed on the bottom flat area on a
small scale.
[0018] Further, the longitudinal and transverse partitions
installed to have the grid pattern may include at least one air
flow hole, which enables the spatial areas to communicate with each
other such that the air can flow between the spatial areas.
[0019] In addition, the transverse partitions may be subjected to
height adjustment according to operating conditions of the vessel,
and the longitudinal and transverse partitions may be installed on
the bottom of the recess formed in a flat area of the bottom of the
vessel.
[0020] According to the present invention, the air is supplied to
the spatial areas partitioned by the longitudinal and transverse
partitions, thereby forming small-scale multiple air layers on the
flat area of the bottom of the vessel. In comparison with a
large-scale single air layer, the air layers are not easily
destroyed on still and rough sea conditions, and easily fixed to
the bottom of the vessel, so that a resistance reducing effect is
continuously and stably produced. This contributes to the air
layers being stable, because a surface tensile force between the
air and water, one of the air layer formation mechanisms of the
bottom of the vessel, is relatively high at the small-scale
multiple air layers compared to the large-scale single air
layer.
[0021] Further, the air is not individually supplied to the spatial
areas in order to form the small-scale multiple air layers, but it
is supplied only at the fore of the bottom of the vessel. Air flow
holes are formed in each partition, and the air flows through the
air flow holes, so that it is possible to facilitate pressure
equilibrium in the air layers, simplifying the configuration of the
air supply means, and minimizing the power required to supply the
air.
[0022] Further, the edges of the recess of the bottom of the vessel
in which the longitudinal and transverse partitions are formed are
formed in a shape inclined at an angle of 45.degree. in the central
direction of the vessel rather than in a perpendicular shape,
thereby preventing the air layers of the bottom of the vessel from
leaking in lateral directions when the vessel moves left and right
(i.e. rolls), and allowing the air layers to be formed in a stable
and continuous manner in the bottom of the vessel when the vessel
is at sea.
[0023] Also, when the air flow holes supplying air to the spatial
areas are formed they are formed to be separated from the lower end
of each of the longitudinal and transverse partitions by a
predetermined distance, so that the compressed air can smoothly
flow into the neighboring spatial area when the vessel is moving
(rolling and pitching) on the waves.
[0024] Further, when the thickness of the air layer varies
depending on various operating conditions, the transverse
partitions are moved up and down by hydraulic cylinders, so that an
additional increase in resistance caused by the transverse
partitions hitting the water can be reduced.
[0025] Also, the longitudinal and transverse partitions of the air
cavity vessel are installed in a grid pattern, so that the
installation is possible without making structural changes to the
hull. The number of longitudinal and/or transverse partitions can
be changed to suit the length of the vessel when installed, and
thus the air cavity vessel can be easily applied to very large
vessels.
[0026] In addition, the air supply unit installed in the forebody
of the vessel is variably operated, so that the air supply unit can
increase the amount of air supplied when air leaks from the air
layers of the bottom of the vessel which occurs in part because of
the movement of a large vessel, thereby rapidly compensating for
the leakage.
[0027] Further, the air chamber connected with the air supplying
means is installed in the forebody of the vessel, so that the air
chamber can uniformly supply the compressed air to the spatial
areas divided by the longitudinal and transverse partitions. Thus,
the air layers are formed in a stable and continuous manner in the
bottom of the vessel.
BRIEF DESCRIPTION OF THE DRAWINGS
[0028] The above and other objects, features and advantages of the
present invention will be more clearly understood from the
following detailed description when taken in conjunction with the
accompanying drawings, in which:
[0029] FIG. 1 illustrates the configuration of longitudinal and
transverse partitions installed in a recess of the bottom of a
vessel according to the present invention;
[0030] FIG. 2 illustrates the configuration of longitudinal and
transverse partitions having holes or gaps to simplify an air
supply unit according to the present invention;
[0031] FIG. 3 illustrates a vessel to which the present invention
is applied;
[0032] FIG. 4 illustrates the configuration of an air supply unit
according to the present invention; and
[0033] FIG. 5 illustrates the configuration of a transverse
partition and a hydraulic actuator according to the present
invention.
DETAILED DESCRIPTION OF THE INVENTION
[0034] Reference will now be made in greater detail to an exemplary
embodiment of the invention, an example of which is illustrated in
the accompanying drawings. Wherever possible, the same reference
numerals will be used throughout the drawings and the description
to refer to the same or like parts.
[0035] As is well known in the art, when air is injected from the
fore of the vessel into a recess formed in the bottom of the
vessel, friction between the water and a hull surface is converted
into a friction between the air and water by a wide air layer
formed in the bottom of the vessel, so that the largest proportion
of the frictional resistance of the vessel can be remarkably
reduced. However, in large vessels that are moving on the waves, it
is actually difficult to form a stable air layer under all
conditions.
[0036] The present invention is directed to forming a stable air
layer in a large vessel that is moving in rough seas. To this end,
a recess is formed in the bottom of the vessel, and numerous
partitions are installed in the recess in longitudinal and
transverse directions, thereby causing small-scale multiple air
layers rather than a single large air layer to be fixedly formed in
the recess of the bottom of the vessel.
[0037] Hereinafter, the present invention will be described below
with reference to the attached drawings.
[0038] FIG. 1 illustrates the configuration of longitudinal and
transverse partitions installed in a recess of the bottom of a
vessel according to the present invention. FIG. 2 illustrates the
configuration of longitudinal and transverse partitions having air
flow holes to simplify an air supply unit according to the present
invention. FIG. 3 illustrates a vessel to which the present
invention is applied. The present invention is directed to an air
cavity vessel that injects air into the bottom thereof to form air
layers in order to reduce resistance of the vessel. The air cavity
vessel includes transverse partitions 10 partitioning the bottom in
a transverse direction, longitudinal partitions 20 partitioning the
bottom in a longitudinal direction, spatial areas 30 defined in a
grid pattern by the transverse partitions 10 and the longitudinal
partitions 20, an air supply unit 40 installed in a forebody of the
vessel and supplying compressed air into the spatial areas 30, and
means 50 for supplying the compressed air to the air supply unit
40, wherein multiple air layers are formed on a bottom flat area
120 on a small scale.
[0039] The longitudinal and transverse partitions 10 and 20 are
installed in a recess 110 formed in the bottom flat area (i.e. the
flat area of the bottom) in order to form the air layers. To this
end, the numerous transverse partitions 10 are installed to
partition the bottom of the vessel 100 in a transverse direction
and to be parallel to each other, and the numerous longitudinal
partitions 20 are installed to be parallel to each other so as to
intersect the transverse partitions 10 and partition the bottom of
the vessel 100 in a longitudinal direction.
[0040] The longitudinal partitions 20 and the transverse partitions
10 are installed on the bottom in a grid pattern, and the spatial
areas 30 are defined by the longitudinal partitions 20 and the
transverse partitions 10 installed in the grid pattern.
[0041] The spatial areas 30 are open in a downward direction, and a
number of them are formed on the bottom flat area by using the
longitudinal and transverse partitions. Small-scale multiple air
layers are formed on the bottom flat area by the air supplied into
the spatial areas 30.
[0042] Further, the longitudinal and transverse partitions 10 and
20 function to prevent the air of the air layers formed on the
spatial areas 30 from leaking out of the hull when the vessel is
moving (rolling and pitching) in rough seas.
[0043] Further, the longitudinal and transverse partitions 10 and
20 installed to have the grid pattern include at least one air flow
hole 60, which enables the spatial areas 30 to communicate with
each other such that the air can flow between the spatial
areas.
[0044] In detail, each spatial area 30 formed on the bottom flat
area is adapted to communicate with the other neighboring spatial
area by the air flow hole 60. Here, the air flow hole is formed
apart from a lower end of the longitudinal or transverse partition
by a predetermined distance.
[0045] Further, the air flow hole 60 is preferably formed at half
the height of the longitudinal or transverse partition from a lower
end of the longitudinal or transverse partition so as to be free
from any influence resulting from the thickness of the air layer
and to smoothly supply the air into the spatial areas.
[0046] The air supply unit 40 is disposed at a forebody of the
vessel so as to be connected with the spatial areas which are
located at the fore of the vessel. The compressed air supplied from
the air supplying means 50 is supplied to the spatial areas by the
air supply unit 40.
[0047] That is, in the present invention, the compressed air
supplied to the spatial areas located at the fore of the vessel by
the air supply unit 40 installed on the forebody of the vessel
flows into the other numerous spatial areas via the air flow holes
60.
[0048] As illustrated in FIG. 4, the air supply unit 40 includes an
air chamber 41 formed so as to communicate with the air supplying
means 50, a nozzle 42 hinged to the fore of the bottom of the
vessel so as to be located at an end of the air chamber 41, and a
hydraulic part 44 installed in the vessel so as to be connected
with the nozzle 42 and drive the nozzle around a hinge 43.
[0049] The air chamber 41 is connected to a piping system 51 of the
air supplying means 50, and is formed so as to have a larger area
than the piping system, i.e. to be a space expanded from the piping
system, so that the compressed air supplied through the piping
system is uniformly mixed in the air chamber 41 before flowing to
the nozzle 42.
[0050] The nozzle 42 transfers the compressed air supplied from the
air chamber, and is hinged with the fore of the bottom of the
vessel.
[0051] The hydraulic part 44 is connected with the nozzle 42, and
changes the position of the nozzle to adjust the amount of the
compressed air supplied to the spatial area 30. Here, the hydraulic
part 41 may employ a hydraulic cylinder.
[0052] In this way, in the present invention, the nozzle 42 is
adapted to operate around the hinge 43, so that the amount of the
compressed air supplied to the spatial area 30 can be adjusted. The
air chamber 41 is connected with the piping system 51 of the air
supplying means, so that the supplied compressed air can be
uniformly mixed and then supplied to the spatial area.
[0053] Further, the air supply unit 40 is installed only on the
fore of the vessel, and the numerous air flow holes 60 are formed
in the longitudinal and transverse partitions 10 and 20. Thus, the
air supplied at the fore flows through the air flow holes 60, so
that the vessel can be constructed in a more simple structure, and
the pressure between the multiple air layers can be made
uniform.
[0054] Further, the transverse partitions 10 of the present
invention are installed in the bottom 112 of the recess 110 formed
in the bottom flat area such that their heights are adjusted
depending on the operating conditions of the vessel.
[0055] To this end, the present invention is adapted to further
include hydraulic actuators 70 connected with the transverse
partitions 10. Here, the hydraulic actuators 70 may use a hydraulic
cylinder.
[0056] Further, two or more hydraulic actuators 70 are installed in
the hull so as to be connected with each transverse partition 10.
Each transverse partition 10 is displaced up and down by the
hydraulic actuators 70.
[0057] In detail, the thickness of the air layer formed in the
recess of the bottom flat area varies depending on the operating
conditions of the vessel. If the thickness of the air layer is less
than a height h of the longitudinal or transverse partition, the
resistance of the vessel may be increased. If the thickness of the
air layer of the bottom of the vessel is smaller than a depth of
the recess of the bottom flat area depending on the operating
conditions of the vessel, water dashes against the transverse
partition 10 in a direction perpendicular to the direction in which
the vessel is moving, the resistance of the vessel may increase.
For this reason, the height of the transverse partition 10 is
adjusted to the thickness of the air layer by the hydraulic
actuators 70, so that the resistance of the vessel can be
additionally reduced.
[0058] Here, each transverse partition is preferably operated in
the range of a half height thereof by the hydraulic actuators.
[0059] Further, as illustrated in FIG. 5, edges 111 of the recess
110 are not perpendicular to the bottom of the recess, but form an
angle .theta. in relation to the central direction of the vessel.
Here, the angle .theta. is preferably about 45.degree.. The edges
111 of the recess prevent lateral leakage of the air layers of the
bottom of the vessel when the vessel moves left and right (i.e.
rolls).
[0060] Although an exemplary embodiment of the present invention
has been described for illustrative purposes, those skilled in the
art will appreciate that various modifications, additions and
substitutions are possible, without departing from the scope and
spirit of the invention as disclosed in the accompanying
claims.
* * * * *