Watercraft

Abstract

A marine vessel 10 comprises a deck 11 and a superstructure 12 that comprises at least two elongate portions 13a and 13b mounted on the deck, positioned either side of the centreline of the vessel, an

Description

10 09 25 BACKGROUND TO THE INVENTION 5 The present invention relates to a marine vessel (or ship) comprising a superstructure. Marine vessels having a superstructure (i.e. a portion protruding above the deck of the vessel) are well known in the art. For example, large bulk carriers or container ships may have a large superstructure (also known as an accommodation) which protrudes from the 10 deck of the ship. Such known superstructures are typically cuboidal in shape, and extend across the majority of the beam of the ship. The superstructure may be used to house the navigational bridge of the vessel, crew accommodation, machinery, or as interior space relating to other functions of the vessel. 15 However, vessels with such known superstructures may suffer from high drag associated with the shape of the superstructure whilst the vessel is in motion. In particular, the cuboidal superstructure may act as a bluff body when the vessel is in motion, creating aerodynamic drag, with an area of low pressure air and trailing vortices behind the superstructure. This may cause the vessel to suffer from high aerodynamic drag, and result 20 in low fuel efficiency. It is the aim of the present invention to at least partially address the problems noted above. SUMMARY OF THE INVENTION 25 According to the present disclosure, there is provided a marine vessel comprising a deck and a superstructure; the superstructure comprising at least two elongate portions mounted on the deck, positioned either side of the centreline of the vessel, and defining a gap therebetween, the elongate portions being elongate in the fore-aft direction of the vessel, 30 wherein the elongate portions have a rounded leading edge; wherein the elongate portions extend substantially perpendicular to the deck, wherein the elongate portions comprise a useable interior space, wherein the elongate portions are aerofoil portions having a substantially aerofoil cross section, wherein the aerofoil portions are cambered, and wherein the total number of elongate portions is two and / or the superstructure further 10 09 25 comprises a joining portion spanning the elongate portions, wherein the joining portion houses the navigational bridge of the vessel. Such a configuration may result in reduced aerodynamic drag, whilst maintaining the functionally useable space inside the superstructure. This configuration may also allow the elongate portions to act as an 5 aerofoil, creating a resultant force with a forward component. In turn, this may provide an additional propulsive force to the vessel. Optionally, the cross section of each elongate portion parallel to the deck tapers towards the stern of the vessel. 10 According to the present disclosure, there is also provided a marine vessel comprising a deck and a superstructure; the superstructure comprising at least two elongate portions mounted on the deck, positioned either side of the centreline of the vessel, and defining a gap therebetween, the elongate portions being elongate in the fore-aft direction of the 15 vessel; wherein the cross section of each elongate portion parallel to the deck tapers towards the stem of the vessel, wherein the elongate portions extend substantially perpendicular to the deck, wherein each elongate portion comprises a useable interior space, wherein the elongate portions are aerofoil portions having a substantially aerofoil cross section, wherein the aerofoil portions are cambered, and wherein the total number of 20 elongate portions is two and / or the superstructure further comprises a joining portion spanning the elongate portions, wherein the joining portion houses the navigational bridge of the vessel. Such a configuration may result in reduced aerodynamic drag, whilst maintaining the functionally useable space inside the superstructure. This configuration may also allow the elongate portions to act as an aerofoil, creating a resultant force with a 25 forward component. In turn, this may provide an additional propulsive force to the vessel. The elongate portions are aerofoil portions have a substantially aerofoil cross section. This may provide a further improved aerodynamic benefit as described above. 30 Optionally, the span of each aerofoil portion is substantially perpendicular to the deck. Optionally, the chord of each aerofoil portion is substantially parallel to the fore-aft direction of the vessel. 10 09 25 Optionally, the thickness to chord ratio of each aerofoil portion is 10%-40%. Optionally, the thickness to chord ratio of each aerofoil portion is 20-30%. Ratios in these ranges may be low enough for each aerofoil portion to generate lift, whilst also being high enough to retain a useable interior space. 5 Optionally, the elongate portions have an aspect ratio of at least 3:1, the aspect ratio being the length of the elongate portion in the fore aft direction of the vessel divided by the width of the elongate portion in the beamwise direction of the vessel. These aspect ratios may allow the flow to recover quickly in the wake of the superstructure, and may thus minimise 10 drag. Optionally, the aspect ratio is at least 4:1. Optionally, the joining portion spans the elongate portions at a position located in the top 15 half of the elongate portions. This may allow line of sight requirements to be met. This may also allow the joining portion to act as an endplate, which may improve lift generated by the elongate portions. Optionally, the elongate portions are configured to support the weight of the joining 20 portion. Optionally, the elongate portions are in a fixed position relative to the deck. Optionally, the interior space is for use other than mere access to the interior of the 25 elongate portion. Optionally, the interior space is subdivided into a plurality of rooms. Optionally, the interior space is for use as one or more of a storage area, a crew 30 accommodation area, a sleeping area, a navigational bridge, an exhaust space, and a machinery room. Optionally, the elongate portions comprise at least one window. Optionally, the elongate portions are coterminous with the deck. 10 09 25 Optionally, the elongate portions are located in the aft-most 25% of the total length of the deck in the fore-aft direction. 5 Optionally, the height of the elongate portions is at least 25% of the beam of the vessel. Optionally, the width of each elongate portion at its widest point is between 5% and 30% of the beam of the vessel. 10 Optionally, the total width of the elongate portions at their widest points is between 10% and 70% of the beam of the vessel. Optionally, the elongate portions are tapered along their height. 15 Optionally, the elongate portions include at least one flow conditioning device. The flow conditioning device may be moveable or fixed. This may provide improved aerodynamic benefits over a range of apparent wind angles. 20 Optionally, the flow conditioning device includes one or more of a leading edge slat, a trailing edge flap, an endplate, a boundary layer blowing device, and a boundary layer suction device. Optionally, the vessel is a cargo ship. 25 Optionally, the vessel is a monohull vessel. Optionally, the vessel has a displacement hull. 30               BRIEF DESCRIPTION OF THE DRAWINGS The present invention will now be described, by way of non-limitative example only, with reference to the accompanying drawings, in which: 10 09 25 Figure 1 shows a schematic perspective view of a marine vessel according to the present invention; Figure 2 shows a close-up perspective view of the stern of the vessel shown in figure 1; Figure 3 shows a further close-up perspective view of the stem of the vessel shown in figure 1; Figure 4 shows a plan view of the stern of the vessel shown in figure 1; Figure 5 shows a schematic perspective view of the stem of a further vessel according to the present invention; Figure 6 shows a further perspective view of the vessel shown in figure 5; Figure 7 shows a schematic perspective view of the stem of a further vessel according to the present invention; Figure 8 shows a plan view of the stern of the vessel shown in figure 7; Figure 9 shows a schematic perspective view of the stem of a further vessel according to the present invention; Figure 10 shows a plan view of the stem of the vessel shown in figure 9; Figure 11 shows a schematic perspective view of the stem of a further vessel according to the present invention; Figure 12 shows a plan view of the stem of the vessel shown in figure 11; and Figure 13 shows further examples of possible cross-sectional shapes of the elongate portions; and Figure 14 shows the airflow around two elongate portions and the resulting forces. 5 DETAILED DESCRIPTION 10 09 25 The present invention relates to a marine vessel 10. As shown in figure 1, the marine 5 vessel comprises a deck 11, a superstructure 12 and a hull 15. The hull 15 of the vessel (and thus the deck 11, which extends along the top of the hull 15) extends in a fore-aft direction. The superstructure 12 comprises a first elongate portion 13a and a second elongate portion 13b. The elongate portions 13a, 13b are elongate in the fore-aft direction. The two elongate portions 13a, 13b are mounted on the deck 11. In other words, the 10 elongate portions extend substantially vertically upwards from the deck. The elongate portions 13a, 13b are positioned either side of the centre line of the vessel, defining a gap therebetween. In other words, the elongate portions are two separate portions, and do not extend continuously across the beamwise direction (i.e. the width) of 15 the vessel. Thus, the superstructure can be considered to be “split” into a port portion and a starboard portion. As will be explained later, this may provide an aerodynamic benefit. In the arrangement shown in figures 1-4, the elongate portions have a rounded leading edge. The elongate portions also taper towards the stern of the vessel. That is, the cross- 20 section of each elongate portion, taken parallel to the deck, is tapered towards the stern. In the arrangement of figures 1-4, the width of the elongate portions at the aft-most point is narrower than the width of the elongate portions at the fore-most point, thus providing the tapered cross-section. 25 As can be seen in figure 4, the rounded leading edge and taper result in the cross-sectional shape (when taken as a slice parallel to the deck) being a substantially aerofoil shape. Thus, the elongate portions can be considered to be aerofoil portions. As shown in figures 1-4, each aerofoil portion is oriented such that the span of the aerofoil portion is substantially perpendicular to the deck. As also shown in figures 1-4, each aerofoil portion 30 is oriented such the chord of the aerofoil portion is substantially parallel to the fore-aft direction of the vessel. It will be understood that the term “aerofoil portion” need not be any particular aerofoil shape, or a complete aerofoil shape (such as that used in an aircraft wing), but rather need 6 10 09 25 only have a substantially rounded leading edge and a taper towards the rear. Further, it will be understood that a “rounded leading edge” need not be defined by a continuous curve, but be made up of a plurality of linear sections which are shaped to form a polygon having a similar aerodynamic effect to a continuous curve. 5 The elongate portions 13a, 13b also comprise a usable interior space. In other words, the elongate portions are not solid, but rather contain space therein which can be used for various purposes. It will be understood that the term “usable interior space” indicates that the purpose of the space is not merely (i.e. solely) to enable access to the interior of the 10 elongate portions themselves (e.g. for maintenance), but serves for an additional purpose. For example, the interior space may be used as one or more of a storage area, an accommodation area, a sleeping area, a navigational bridge, an exhaust space, and a machinery room. Further, the interior space may be sub-divided into a plurality of rooms. The interior space may also comprise a plurality of storeys (i.e. have a number of interior 15 decks at different levels). The elongate portions 13a, 13b, as shown in figures 1-4, may provide a superstructure having reduced drag, compared to a known cuboidal superstructure extending across the width of a vessel, by virtue of their shape. Dividing the superstructure into two narrower 20 portions (compared to the known superstructures described above), with a gap between the portions, may allow the flow to recover more quickly in the wake of the superstructure (i.e. reduce the size of the region of separated flow downstream of the superstructure). Likewise, the shape of the elongate portions (including the rounded leading edge and taper) may also reduce the size of the wake produced by the superstructure. This may provide 25 lower aerodynamic drag. This may in turn result in increased fuel efficiency and / or reduced fuel consumption. Further, for arrangements where there is some reduction in frontal area compared to the known arrangements described above, the reduced frontal area and gap defined between 30 the elongate portions may mean that airflow is blocked across a smaller proportion of the width of the vessel, thus reducing the size of the wake produced by the superstructure. However, it will be understood that, even for arrangements of the invention with an equivalent frontal area to the known arrangements described above, the above aerodynamic 10 09 25 effects associated with dividing the superstructure into two portions and shape of the elongate portions may still apply. Further, the shape of the elongate portions may provide a further benefit when the wind is at an angle to the direction of travel of the boat, by acting as an aerofoil. In particular, the shape of the elongate portions may result in an area of lower pressure on one side of the aerofoil, and an area of higher pressure on the other side of the aerofoil, thus creating a net resultant force Fres, in a similar manner to a sail. This principle is illustrated in figure 14, which depicts streamlines of the airflow around two elongate portions 13 a, 13b. The lift and drag forces produced by the elongate portions are depicted by arrows Fl and Fd respectively. It will be noted that the lift force Fl has a forward component. Thus, when the wind W is at certain angles (such as that shown in figure 14), the resultant force produced by the elongate portions may have a net forward component, which may in turn contribute to the thrust of the vessel. This effect may be present to some extent at apparent wind directions of between 0 and 80 degrees from the bow. This may result in yet further increased fuel efficiency and / or reduced fuel consumption. The combination of the shape of the elongate portions, combined with the elongate portions having a useable interior space, may provide the above aerodynamic benefits, whilst also allowing the superstructure to fulfil the same functional purpose as a conventional superstructure. In other words, the superstructure of the present invention provides reduced drag and improved fuel consumption, whilst maintaining the usability and utility of the superstructure. As shown in figures 1-4, the vessel may comprise a joining portion 14 which spans between the first elongate portion 13a and the second elongate portion 13b. It will be noted that, in such an arrangement, a gap is nonetheless defined between the elongate portions, because the joining portion spans the gap without completely blocking the gap, because does not extend all the way to the deck in the vertical direction. That is, the joining portion 14 spans only a portion of the height (i.e. not the full height) of the elongate portions. In some arrangements, the joining portion 14 may span the elongate portions at a position located in the top half of the elongate portions. It will be understood that, in such an 8 10 09 25 arrangement, the elongate portions 13a, 13b support the weight of the joining portion 14. In the arrangement shown in figures 2 and 3, the joining portion spans elongate portions at their uppermost point. The joining portion 14 may house the navigational bridge of the vessel. In arrangements where the joining portion spans the elongate portions in the top half of the elongate portions, the provision of the navigational bridge in the joining portion may provide for good visibility from the bridge, and may also allow line of sight requirements to be met, whilst nonetheless providing low aerodynamic drag due to the gap formed under the joining portion and between the elongate portions. Locating the joining portion on top of the elongate portions may also to some extent enable it to act as an endplate, thus increasing the pressure difference from one side of the elongate portion to the other when acting as an aerofoil (as described above). It will be understood that figures 1-4 are schematic figures, which are designed to illustrate the principle of the invention by showing only the pertinent parts, and that vessels according the invention may include further features. An example of an arrangement with further features is shown in figures 5 and 6, which depict a similar arrangement to that of figures 1-4, with a superstructure 52 including elongate portions 53a, 53b, and a joining portion 54, but show additional structural details of the vessel. For example, as shown in figures 5 and 6, the elongate portions 53a, 53b may comprise a plurality of windows 56 or portholes. It will be understood that the particular arrangement of windows shown in figures 5 and 6 (with windows provided in the rounded leading edge and in the sides of the elongate portions) is merely an example, and that any suitable arrangement of windows 56 may be chosen. As shown in figures 5 and 6, the elongate portions 53a, 53b may further comprise openings 57 (other than windows or portholes) therein. Such openings may provide access to the useable interior space. For example, the openings may allow equipment, such as life rafts or tenders, to be stored in the interior space of the elongate portions. As further illustrated in figures 5 and 6, the elongate portions may be provided with further features. For example, a crane 58 is provided on the top of elongate portion 13a. Further, 9 10 09 25 staircases 59 may be present on the exterior of the elongate portions, which may provide access to the interior of the elongate portions at differing heights, and may also provide emergency escape routes from the interior space. Figures 7 and 8 depict a further variation of the arrangements of figures 1-6. In particular, the vessel of figures 7 and 8 comprises a superstructure 72 with two elongate portions 73a, 73b (which are elongate portions having the same shape as the arrangements of figures 1-6), but does not comprise a joining portion. It will be understood that any of the features shown in figures 5 and 6 may also be applied to the arrangement of figures 7 and 8. Figures 9 and 10 depict a further arrangement of marine vessel, similar to that depictured in figures 7 and 8. In particular, the vessel of figures 9 and 10 comprises a superstructure 92 with two elongate portions 93 a, 93b. However, in the arrangement of figures 9 and 10, the elongate portions 93a, 93b comprise a rounded leading edge, but do not taper towards the stern of the vessel. In other words, the cross-sectional shape of the elongate portions is a rectangle with a rounded leading edge. It will be understood that any of the other features of figures 1-6 may be applied to an arrangement with elongate portions having the shape shown in figures 9 and 10. For example, a joining portion 14, including, for example, a navigational bridge, may be applied to such an arrangement. Figures 11 and 12 depict a further arrangement of marine vessel, similar to that depictured in figures 7 and 8. In particular, the vessel of figures 11 and 12 comprises a superstructure 112 with two elongate portions 113a, 113b. However, in the arrangement of figures 11 and 12, the elongate portions taper towards the stem of the vessel, but do not comprise a rounded leading edge. Rather, the leading edge is a flat surface. In other words, the cross-sectional shape of the elongate portions 113a, 113b is tapered with a substantially flat leading edge. Such a shape may be considered to be an aerofoil with a blunted leading edge. It will be understood that any of the other features of figures 1-6 may be applied to an arrangement with elongate portions having the shape shown in figures 11 and 12. For example, a joining portion 14, including, for example, a navigational bridge, may be applied to such an arrangement. It will be appreciated that numerous other cross-sectional shapes of elongate portion may be provided, and may have the aerodynamic benefits described above. In particular, any 10 10 09 25 shape which has a rounded leading edge and / or has a taper towards the stern may be used. Examples of such shapes are shown in figures 13a-131. These cross-sectional shapes may be applied to any of the arrangements described above and depicted in figures 1-12. It will be noted that in some arrangements shown in figures 13a-l31, a rounded leading edge but no taper is present (see, for example, figures 13a, 13b and 131), in some arrangements, a taper but no rounded leading edge is present (see, for example, figures 13c, 13d, and 13e), and in some arrangements (see, for example, figures 13f, 13g, 13h, 13i, 13j and 13k), both a rounded leading edge and taper are present. In the arrangements shown in figures 1-8, the aspect ratio of the elongate portions is approximately 4:1. The aspect ratio is defined as the length of the elongate portion in the fore-aft direction of the vessel divided by the width of the elongate portion in the beamwise direction of the vessel. However, the aspect ratio is not limited to this value, and in some arrangements may be, for example, at least 3:1, or at least 4:1. For an elongate portion which is considered to be an aerofoil portion, a thickness to chord ratio can also be defined, as the maximum thickness of the aerofoil shape divided by the chord length of the aerofoil shape. In the arrangements shown in figures 1 -4, the aerofoil portion has a thickness to chord ratio of approximately 25%. It will be understood that this value corresponds to an aspect ratio of 4:1. However, the thickness to chord ratio is not limited to this number, and may be, for example 10% - 40%, or preferably 20% - 30%. For elongate portions which have an aerofoil cross section, the cross-section of the aerofoil may be cambered or may be uncambered. In the arrangements shown in figures 1-12, it will be noted that the total number of elongate portions is two. In other words, there are no more than two elongate portions. However, it will also be understood that arrangements are possible in which more than two elongate portions are provided. For example, three elongate portions may be provided, with respective gaps being defined between adjacent elongate portions. In the arrangements shown in figures 1-12, the elongate portions are in a fixed position relative to the deck. In other words, the elongate portions do not move relative to the deck. 11 10 09 25 However, in some arrangements, the elongate portions may additionally include at least one flow conditioning device. The flow conditioning device may be static or may be movable. For example, the flow conditioning device may include one or more of a leading edge slat, a trailing edge flap, an end plate, a boundary layer blowing device, and a 5 boundary layer suction device. This may further improve the aerodynamic effects described above. For example, such devices may result in reduced drag, and / or may increase the range of wind angles over which a force with a net forward component is produced. 10 It will be noted that in the arrangements depicted in figures 1-12, the cross-section of the elongate portions is substantially constant along its height. However, arrangements are also possible in which the elongate portions are tapered along their height (i.e. the cross section at the top of the elongate portions is smaller than the cross section at the bottom of the elongate portions). It will be understood that the variation in cross-section may be 15 continuous or stepwise, and be along all or part of the height of the elongate portions. In such arrangements, the shape of the cross-section may be substantially constant, with only the size of the cross-section reducing towards the top of the elongate portion. In other arrangements, the shape of the cross-section of the elongate portions may alternatively or additionally vary along the height of the elongate portions. 20 In the arrangements illustrated in figures 1-12, the elongate portions are coterminous with the deck. In other words, the elongate portions extend upwards from the deck and are mounted on the deck so that the bottom of each elongate portion is in contact with the upper surface of the deck. However, it will be understood that in some arrangements, the 25 elongate portions may be mounted on a surface which is itself mounted on the deck (i.e. a platform on the deck). Further, in some arrangements, the interior shape of the elongate portions may extend below the deck. In the arrangements illustrated in figures 1-12, the superstructure (and thus the elongate 30 portions) are located towards the stem (i.e. the rear) of the vessel. Preferably, the elongate portions are located in the aft-most 25% of the total length of the deck in the fore-aft direction. 10 09 25 In some arrangements, the elongate portions may be at different positions in the fore-aft direction. This may be particularly beneficial when the superstructure comprises more than two elongate portions. For example, in arrangements where the superstructure comprises three elongate portions, there may be two elongate portions as illustrated in any 5 of figures 1-12, and a third elongate portion (which may be substantially on the centreline of the vessel, or displaced from the centreline), at a different fore-aft position. In the arrangements illustrated in figures 1-12, the height of the elongate portions is approximately 58% of the beam (i.e. width) of the vessel. However, it will be understood 10 that any suitable height as a proportion of the beam may be chosen. For example, the height of the elongate portions may be at least 25% of the beam of the vessel, may preferably be at least 40% of the beam of the vessel, and may more preferably be 40%-60% of the beam of the vessel. The height may be chosen based on line of sight criteria, so that, when a navigational bridge is provided as part of the superstructure, suitable lines of 15 sight are available from the bridge. In the arrangements illustrated in figures 1-12, the width of each elongate portion is approximately 25% of the beam (i.e. width) of the vessel. However, it will be understood that any suitable width as a proportion of the beam may be chosen. For example, the width 20 of each elongate portions at its widest point may be between 5% and 30% of the beam of the vessel, and preferably 10-25% of the beam of the vessel. In the arrangements illustrated in figures 1-12, the total width of the elongate portions is approximately 50% of the beam (i.e. width) of the vessel (i.e. twice the width of each 25 elongate portion). However, the total width is not limited to this value, and the total width of the elongate portions at their widest points may be between 10% and 70% of the beam of the vessel. It will be understood that the total width of the elongate portions is not necessarily twice the width of each elongate portion, because, as explained above, the superstructure may comprise more than two elongate portions. 30 The positioning of the elongate portions either side of the centre line of the vessel may be such that they are distributed substantially symmetrically either side of the centre line. In other arrangements, the elongate portions may be distributed asymmetrically either side of the centre line. Although the arrangement of the present invention may be applied to any marine vessel, the present invention may be particularly suitable for cargo ships, such as bulk carriers or tankers or container ships. The arrangement of the present invention may also be 5 particularly beneficial for monohull vessels. The present invention may also provide a particular benefit to vessels with displacement hulls, rather than planing hulls. It should be understood by those skilled in the art that while the present invention has been described with reference to exemplary embodiments, it is not limited to the disclosed 10 exemplary embodiments. Various modifications, combinations, sub-combinations and alterations may occur depending on design requirements and other factors insofar as they are within the scope of the appended claims or the equivalents thereof. Features from any example or embodiment of the present disclosure can be combined with features from any other example or embodiment of the present disclosure. 10 09 25

Claims

10 09 251. A marine vessel comprising a deck and a superstructure;the superstructure comprising at least two elongate portions mounted on the deck, positioned either side of the centreline of the vessel, and defining a gap therebetween, the elongate portions being elongate in the fore-aft direction of the vessel;wherein the elongate portions have a rounded leading edge;wherein the elongate portions extend substantially perpendicular to the deck;wherein the elongate portions comprise a useable interior space;wherein the elongate portions are aerofoil portions having a substantially aerofoil cross section, wherein the aerofoil portions are cambered; andwherein:the total number of elongate portions is two; and / orthe superstructure further comprises a joining portion spanning the elongate portions, wherein the joining portion houses the navigational bridge of the vessel.

2. The vessel of claim 1, wherein the cross section of each elongate portion parallel to the deck tapers towards the stern of the vessel.

3. A marine vessel comprising a deck and a superstructure;the superstructure comprising at least two elongate portions mounted on the deck, positioned either side of the centreline of the vessel, and defining a gap therebetween, the elongate portions being elongate in the fore-aft direction of the vessel;wherein the cross section of each elongate portion parallel to the deck tapers towards the stem of the vessel;wherein the elongate portions extend substantially perpendicular to the deck;wherein each elongate portion comprises a useable interior space;10 09 25wherein the elongate portions are aerofoil portions having a substantially aerofoil cross section, wherein the aerofoil portions are cambered; andwherein:the total number of elongate portions is two; and / orthe superstructure further comprises a joining portion spanning the elongate portions, wherein the joining portion houses the navigational bridge of the vessel.

4. The vessel of any preceding claim, wherein the span of each aerofoil portion is substantially perpendicular to the deck.

5. The vessel of any preceding claim, wherein the chord of each aerofoil portion is substantially parallel to the fore-aft direction of the vessel.

6. The vessel of any preceding claim, wherein the thickness to chord ratio of each aerofoil portion is 10%-40%.

7. The vessel of claim 6, wherein the thickness to chord ratio of each aerofoil portion is 20-30%.

8. The vessel of any preceding claim, wherein the elongate portions have an aspect ratio of at least 3:1, the aspect ratio being the length of the elongate portion in the fore aft direction of the vessel divided by the width of the elongate portion in the beamwise direction of the vessel;9. The vessel of claim 8, wherein the aspect ratio is at least 4:1.

10. The vessel of any preceding claim, wherein the joining portion spans the elongate portions at a position located in the top half of the elongate portions.

11. The vessel of any of any preceding claim, wherein the elongate portions are configured to support the weight of the joining portion.10 09 2512. The vessel of any preceding claim, wherein the elongate portions are in a fixed position relative to the deck.

13. The vessel of any preceding claim, wherein the interior space is for use other than access to the interior of the elongate portion.

14. The vessel of any preceding claim, wherein the interior space is subdivided into a plurality of rooms.

15. The vessel of any preceding claim, wherein the interior space is for use as one or more of:a storage area;a crew accommodation area;a sleeping area;a navigational bridge;an exhaust space; and a machinery room.

16. The vessel of any preceding claim, wherein the elongate portions comprise at least one window.

17. The vessel of any preceding claim, wherein the elongate portions are coterminous with the deck.

18. The vessel of any preceding claim, wherein the elongate portions are located in the aft-most 25% of the total length of the deck in the fore-aft direction.

19. The vessel of any preceding claim, wherein the height of the elongate portions is at least 25% of the beam of the vessel.

20. The vessel of any preceding claim, wherein the width of each elongate portion at its widest point is between 5% and 30% of the beam of the vessel.10 09 2521. The vessel of any preceding claim, wherein the total width of the elongate portions at their widest points is between 10% and 70% of the beam of the vessel.

22. The vessel of any preceding claim, wherein the elongate portions are tapered along their height.

23. The vessel of any preceding claim, wherein the elongate portions include at least one flow conditioning device;24. The vessel of claim 23, wherein the flow conditioning device includes one or more of a leading edge slat, a trailing edge flap, an endplate, a boundary layer blowing device, and a boundary layer suction device.

25. The vessel of any preceding claim, wherein:the vessel is a cargo ship; and / or.the vessel is a monohull vessel; and / or.the vessel has a displacement hull.

Images