Patent Description:
Fouling (e.g. biological growth including algae, weeds and barnacles) of vessels and in particular of the hulls of vessels is a known problem. If left uncontrolled, such growth will increase the weight of the vessel and its drag. This is likely to reduce the efficiency of the vessel, impact its handling and have an overall effect on performance. It is therefore important to reduce or prevent such growth.

Traditionally, such biological growth would be removed manually either through the use of a dry-dock or by diving. However, particularly where a dry-dock is used, this can result in a significant amount of time where the vessel is out of use and can be costly. Alternatively, the growth may be removed or inhibited chemically, for example, by applying a biocidal coating to the surface. However, such chemicals are generally harmful from an environmental point of view. Accordingly, it is advantageous to provide a solution which minimises the time a vessel is taken out of use, preferably to zero, and/or does not make use of such potentially harmful chemicals.

One such solution comprises the use of electrodes positioned on opposite sides of the vessel, and an electrical current provided between the two causes electrolysis of the surrounding seawater. This results in the formation of, for example, chlorine and sodium hypochlorite which act to remove such biological growth from the hull.

Alternatively, some anti-fouling systems may use one or more transducers to apply ultrasonic vibrations to the hull causing disruption to any biological growth present on the hull and/or preventing new growth thereon. Specifically, such systems use the application of ultrasonic vibrations to problematic surfaces to causes non-inertial cavitation of the liquid, e.g. seawater, adjacent to the surface causing a microscopic agitation of the biological growth on the surface, causing it to break up and deteriorate. However, in general, such solutions are only provided for preventing/reducing fouling of the hull of the vessel, whereas other components of the vessel may in fact be submerged during normal use of the vessel and are hence likely to be susceptible to fouling.

One such component may comprise a cooling system of the vessel, for instance a keel cooler which may include a pipework arrangement provided in thermal contact with the water acting as a heat exchanger for removing heat from coolant flowing through the cooler. Biological growth on the exterior of the cooler can inhibit this heat exchange process resulting in the coolant not being cooled adequately. In certain scenarios, for example where the coolant is provided for the controlling the temperature of an engine of the vessel, a reduction in the efficiency of this heat exchange process can result in a significant reduction in the operational efficiency of the engine through overheating. This can lead to increased fuel consumption, increased emission levels and ultimately engine failure if not kept under control. It is therefore important to ensure adequate operation of such cooling systems.

It would therefore be advantageous to provide means allowing for the use of an ultrasonic anti-fouling device to be used to prevent fouling of a cooling system, such as a keel cooler, of a vessel.

<CIT> reveals a heat exchanger arranged for placement in a compartment of a vessel, which is provided with heat exchanging elements and a base with an inlet and outlet which are connected to the heat exchanging elements for transporting a liquid from the inlet through the heat exchanging elements to the outlet for exchanging heat between said liquid and outboard water in the compartment, wherein the heat exchanger further comprises an anti-fouling system arranged to reduce fouling of the heat exchanging elements, wherein the anti-fouling system comprises at least one vibrating device in contact with the heat exchanger and arranged for vibrating the heat exchanging elements to reduce fouling thereof.

<CIT> discloses a shell including walls that collectively define an interior space of the shell, the interior space sized and configured to receive heat generating equipment. An internal heat exchanger disposed within the interior space is arranged for thermal communication with heat generating equipment when heat generating equipment is located in the interior space. Additionally, an external heat exchanger is located outside of the shell and arranged for fluid communication with the internal heat exchanger. Finally, a prime mover is provided that is in fluid communication with the internal heat exchanger and the external heat exchanger, and the prime mover is operable to circulate a flow of coolant through the internal heat exchanger and the external heat exchanger.

<CIT> discloses an ultrasonic scale removing device provided to remove scale of a plate heat exchanger by using an ultrasonic generator. A vibration transfer plate is installed in the side of the plate heat exchanger and the ultrasonic generator is welded in the vibration transfer plate. The device constitutes: an ultrasonic scale removing device comprising a vibration transfer plate, a coupling unit, and an ultrasonic generator. The front side of the vibration transfer plate is installed to be in contact with the sides of heat exchange plates. The coupling unit is installed in the rear of the vibration transfer plate. One side of the coupling unit is fixed in a heat exchanger and the other thereof is contacted with the vibration transfer plate to pressurize the vibration transfer plate toward the front side. The ultrasonic generator is fixed in the rear of the vibration transfer plate by welding.

<NPL> provides an example of practical application of energy saving by fitting the central cooling system with keel cooler on the Car Ferry "ASD" trading in west Africa. The use of that solution is limited to small ships, with new development, central cooling system with keel coolers has a chance to spread out on bigger ships in the future. It will mainly depend on efficiency and reliability of keel coolers secure systems.

It is an aim of an embodiment or embodiments of the invention to overcome or at least partially mitigate one or more problems discussed herein.

According to an aspect of the invention there is provided a mounting device for an anti-fouling system of a vessel in accordance with claim <NUM>.

Advantageously, the mounting device of the present invention provides means to mount (and vibrationally couple) an ultrasonic transducer to a cooling system of a vessel. In this way, the transducer may be used to apply a vibration to the cooling system, e.g. one or more pipes of the system, to prevent or reduce biological growth thereon. Advantageously, the mounting device of the present invention may increase or maintain an operational efficiency of the cooling system, and as such an operational efficiency of one or more systems of the vessel, e.g. an engine.

The securing means comprises a collar configured to be mounted about a standpipe of the inlet or outlet of the cooling system of the vessel. The collar may comprise a substantially circular aperture therethrough facilitating mounting of the collar about a substantially cylindrical standpipe, in use. The collar may be configured to be mounted about a standpipe having a diameter of <NUM> inches, <NUM> inches, <NUM> inches or <NUM> inches, (respectively <NUM>,<NUM>, <NUM>,<NUM>, <NUM>,<NUM> or <NUM>,<NUM>) for example, although the collar may be configured to be mounted about a standpipe of any diameter.

The collar may be threaded such that the mounting device may be threaded onto a threaded standpipe of the cooling system. The thread may comprise an NPT or NPS-M thread, for example, although any suitable thread pattern may be provided as required by the end application.

The collar may comprise a smooth, non-threaded collar sized to fit about a smooth standpipe, such as a flanged or collared standpipe of the cooling system.

The collar may comprise a split collar. The split collar may preferably be formed of two half collars which may be hinged or otherwise connected at one or more locations such that the two half collars may be positioned about the standpipe of the cooling system, in use.

The mounting device may be configured to be mounted directly onto a standpipe of the cooling system. In some embodiments, the mounting device may be configured to be mounted onto a standpipe of the cooling system, and be positioned in contact with one or more components thereof, for example in contact with a nut, bolt, washer or the like forming a connection means for connecting the cooling system to a further component of the vessel, for example for connecting a keel cooler to an exterior surface of a vessel.

The transducer plate may be substantially flat, for example, the transducer plate may comprise a substantially flat upper surface onto which the transducer may be mounted, in use. The transducer plate may comprise one or more notches, apertures or ridges therein to locate and/or orientate the transducer thereon.

The transducer plate may be configured such that the transducer may be secured thereto, through a mechanical connection such as one or more bolts/screws or the like, via welding, or through an adhesive coupling, for example. The transducer plate may be configured such that the transducer may be coupled, connected and/or secured directly or indirectly (e.g. via a transducer ring) thereto.

In use, the transducer plate may be provided with, or be configured to have applied thereto, an acoustic coupling agent such as a liquid, gel or paste for maximising the acoustic coupling between the transducer and the transducer plate.

The transducer plate may be orientated in the same plane as the securing means. For example, the mounting device may be configured such that it may be mounted on a vertical (or substantially vertical) standpipe of an inlet or outlet of the cooling system with the transducer plate being substantially horizontal.

The mounting device may be formed of a single piece, with the transducer plate and securing means being integrally formed. Advantageously, this may reduce cost and complexity in the manufacture of the mounting device.

The mounting device, and the securing means in particular may be made from a material which is equivalent to or complementary to the material of the cooling system. Advantageously, having the mounting device and cooling system made from equivalent or complementary materials may reduce any loss of vibration propagating through the components due to any boundary effects. Furthermore, using equivalent or complementary materials may prevent or reduce the likelihood of galvanic corrosion issues at the point(s) of contact between the mounting device and the cooling system.

The mounting device may comprise or be manufactured from brass or aluminium, for example. In embodiments, the mounting device may be formed of brass where the cooling system or components thereof (e.g. a coupling member such as a bolt or nut to or against which the mounting device may contact in use) comprises a copper-nickel construction. The mounting device may be formed of aluminium where the cooling system or components thereof are formed from aluminium. The mounting device may be formed of carbon fibre. In some embodiments the mounting device may be formed of a copper-nickel material.

According to an aspect of the invention there is provided an anti-fouling system for a vessel, the anti-fouling system comprising a mounting device of any preceding aspect of the invention and one or more ultrasonic transducers.

The anti-fouling system may comprise an anti-fouling system for use with, and to prevent fouling of, a cooling system of the vessel, for example a keel cooler of the vessel.

The anti-fouling system may comprise a plurality of ultrasonic transducers each operable to be coupled to one or more components of the vessel, in use.

The anti-fouling system may comprise a control unit. The control unit may be operable to control operation of the one or more ultrasonic transducers, for example, to control the amplitude, frequency or the like of the output from the one or more ultrasonic transducers.

According to another aspect of the invention there is provided a cooling system of a vessel comprising an anti-fouling system of the preceding aspect of the invention operatively coupled thereto.

The cooling system may comprise a keel cooler of the vessel. The keel cooler may comprise an inlet standpipe and/or an outlet standpipe. The cooling system may comprise an ultrasonic transducer operatively coupled to the inlet standpipe or outlet standpipe of the keel cooler.

According to an aspect of the invention there is provided a vessel comprising the mounting device, anti-fouling system or cooling system according to any preceding aspect.

In general, the present invention relates to a mounting device <NUM>, <NUM>' for an anti-fouling system of a vessel. The mounting device <NUM>, <NUM>' comprises a securing means <NUM>, <NUM>' and a transducer plate <NUM>, <NUM>' operatively coupled to the securing means <NUM>, <NUM>' for coupling a transducer <NUM> to the vessel or a component thereof.

<FIG> illustrates a transducer unit <NUM> which includes a transducer <NUM>, transducer ring <NUM> and cable <NUM>. The transducer ring <NUM> is able to be coupled/uncoupled from the transducer <NUM> through corresponding threaded portions provided on an exterior surface of the transducer <NUM> and an internal surface of the transducer ring <NUM> as shown.

In use, the transducer <NUM> is operable to be mounted to a component, e.g. the transducer plate <NUM>, <NUM>' of the mounting device <NUM>, <NUM>' via the transducer ring <NUM>. The transducer <NUM> is connected to, and is controllable via, a control unit (not shown) via cable <NUM>. The transducer unit <NUM> may comprise one of a plurality of transducer units <NUM> forming an anti-fouling system for the vessel. The transducer <NUM> is operable in use to provide a vibrational output to the component to which it is mounted to, here primarily for the purpose of removing or inhibiting biological growth on a keel cooler <NUM> of the vessel as is described herein.

<FIG> illustrates a keel cooler <NUM> to which a mounting device of the present invention, specifically mounting device <NUM> may be mounted, in use, for reducing and/or inhibiting biological growth thereon. The cooler <NUM> comprises a series of pipes <NUM> through which coolant may flow, in use. When positioned on a vessel, and in normal use, the keel cooler <NUM> is submerged such that heat from the coolant flowing through said pipes <NUM> may be transferred from the coolant to the surrounding water before being recirculated through the vessel's engine. The cooler <NUM> includes an inlet pipe 22a through which coolant enters the cooler <NUM>, and an outlet pipe 22b for through which coolant leaves the cooler <NUM> to be recirculated through the engine. As shown, the inlet and outlet pipes 22a, 22b of cooler <NUM> are threaded.

<FIG> illustrates a first embodiment of a mounting device <NUM> of the present invention. The mounting device <NUM> is specifically configured for coupling the transducer unit <NUM> to the cooler <NUM> described above.

Specifically, the mounting device <NUM> comprises a transducer plate <NUM> and securing means in the form of a securing collar <NUM>. The securing collar <NUM> comprises a split collar formed of a first half collar 16a and second half collar 16b connected to one another to form the circular collar <NUM> with an aperture <NUM> therethrough. The interior surfaces of the two half collars 16a, 16b are threaded corresponding to the thread on a standpipe of an inlet/outlet 22a, 22b of the keel cooler <NUM>.

The transducer plate <NUM> is substantially flat, with an upper surface defining the mounting surface for the transducer unit <NUM> as shown in <FIG>. The transducer plate <NUM> includes mounting apertures (not shown) for coupling the transducer ring <NUM> of the transducer unit <NUM> to the transducer plate <NUM> via one or more mechanical securing means such as bolts or screws.

The transducer plate <NUM> and the securing collar <NUM> may be integrally formed, or may comprise separate components which are welded or otherwise connected to one another. The invention is not limited in this sense.

The mounting device <NUM> is formed from a material which is the same as or complements the material of the component to which it is to be mounted, in use. Specifically, the mounting device may be formed of brass where the cooling system or components thereof (e.g. a coupling member such as a bolt or nut <NUM> to or against which the mounting device <NUM> contacts in use) comprises a copper-nickel construction. The mounting device <NUM> may be formed of aluminium where the cooling system or components thereof are formed from aluminium. Advantageously, having the mounting device and cooling system made from equivalent or complementary materials may reduce any loss of vibration propagating through the components due to any boundary effects. Furthermore, using equivalent or complementary materials may prevent or reduce the likelihood of galvanic corrosion issues at the point(s) of contact between the mounting device <NUM> and the cooling system.

<FIG> illustrates the mounting device <NUM> in position on the inlet 22a of the cooler <NUM>. Specifically, the mounting device <NUM> is mounted on the inlet 22a at a threaded portion <NUM> thereof directly above, but separated from a nut <NUM> and washer <NUM> arrangement forming a connection means for connection and securing the cooler <NUM> to an exterior surface of the vessel. The transducer unit <NUM> is provided mounted on the transducer plate <NUM> of the mounting device <NUM> for providing a vibrational output to the mounting device <NUM> which propagates through said device <NUM> and the inlet 22a, either through the walls of the inlet 22a and/or potentially through the coolant flowing therethrough to provide a vibrational stimulus to the pipes <NUM> of the cooler <NUM>.

<FIG> illustrates a second embodiment of a mounting device <NUM>' in accordance with the present invention. The mounting device <NUM>' is substantially equivalent to mounting device <NUM>, but is instead configured to be mounted to a standpipe 22a' which is smooth, specifically for where the standpipe comprises a flanged standpipe as shown in <FIG>.

Here, rather than having the connection means formed of the nut and washer <NUM>, <NUM> arrangement, the standpipe 22a' is instead coupled to a cooler <NUM>' through coupling of corresponding flanges <NUM>, <NUM>. Specifically, the inlet standpipe 22a'comprises a flange <NUM> at an open end thereof which is coupled, in use, to a flange <NUM> provided on the cooler <NUM>'. Given that the standpipe 22a' is smooth (i.e. not threaded), the mounting device <NUM>' comprises securing means in the form of a securing collar <NUM>' which has a smooth internal surface. Again, and as with securing collar <NUM>, the securing collar <NUM>' comprises a split collar formed of a first half collar 16a' and second half collar 16b' connected to one another to form the circular collar <NUM>' with an aperture therethrough. Otherwise, mounting device <NUM>' is formed in substantially the same manner as mounting device <NUM> described herein.

Claim 1:
A mounting device (<NUM>, <NUM>') for an anti-fouling system of a vessel, the mounting device (<NUM>, <NUM>') comprising:
a securing means (<NUM>, <NUM>') for securing the mounting device (<NUM>, <NUM>') to an inlet (22a, 22a') or outlet (22b) of a cooling system of the vessel; and
a transducer plate (<NUM>, <NUM>') operatively coupled to the securing means (<NUM>, <NUM>') for vibrationally coupling an ultrasonic transducer (<NUM>) to the cooling system of the vessel; characterised in that:
the securing means comprises a collar (<NUM>, <NUM>') configured to be mounted about a standpipe of the inlet (22a, 22a') or outlet (22b) of the cooling system of the vessel.