Component for containing fluid fuel

Abstract

A component 2 for containing fluid fuel which is to be shocked by a shockwave incident on the component. The component includes a first part 4 and a second part 6 which define a chamber 8 configured to contain the fluid fuel. The first part and the second part are connected at a joint 10, at least a portion of which follows a non-linear path, which may be an Archimedean spiral path. The joint may be configured to allow the fluid fuel to be supplied to the chamber. The component may be rotationally symmetric about a central axis.

Description

This invention relates to a component for containing fluid fuel which is to be shocked by a shockwave incident on the component. In particular, this invention relates to components for containing fluid fuel which is to be shocked by a high pressure quasi-spherical shockwave incident on the component, creating high localised concentrations of energy within the fuel. Components for containing fluid fuel to be shocked typically comprise a chamber within the component where the fuel is contained. The component may be formed of two or more parts, connected at a radial joint. In such components, it is advantageous for the properties of the shockwave, and the condition of the fuel, to be strictly controlled, but the joint introduces an inconsistency into the component which may interfere with the properties of the shockwave, and with the condition of the fuel. The present invention aims to provide alternative component designs which reduce the detrimental effects of the joint between two or more parts of the component. When viewed from a first aspect of the present invention, there is provided a component for containing fluid fuel to be shocked by a shockwave incident on the component, the component comprising: a first part; and a second part; wherein the first part and the second part define a chamber configured to contain the fluid fuel; wherein the first part and the second part are connected at a joint; and wherein at least a portion of the joint follows a non-linear path. The invention thus provides a component that is able to hold (e.g. contain) fluid fuel (e.g. liquid and / or gas), such that the fluid fuel may be exposed to a shockwave. In particular, the component may be configured to hold the fluid fuel in the chamber such that the fluid fuel may be exposed to a high pressure shockwave, leading to a collapse of the fluid fuel and a concentration of energy within the fluid fuel which may create the conditions necessary for nuclear fusion to occur. It will be seen that, using a component in accordance with the invention, the nonlinear path of the joint reduces or may even eradicates the presence of material jets and / or expelled gas shocks. As such, the interaction of the shockwave with the fluid fuel in the chamber is not affected by said material jets and / or expelled gas shocks, potentially leading to a more efficient fuel collapse and hence a higher fusion yield. The component is formed from at least two parts. The component comprises a first part and a second part. The first part and the second part may be connected in any suitable and desired way to form the component. In some embodiments, the first part may rest (e.g. on top of) the second part, e.g. such that the first part and the second part abut against each other. The first part and the second part may be any suitable and desired shape. In some embodiments, the first part and / or the second part of the component are substantially rotationally symmetric about an axis (i.e. an axis of symmetry), e.g. an axis through (e.g. the centre of) the component, e.g. through the (e.g. centre of the) chamber. In some embodiments, the first part and the second part share the same axis of symmetry when they are assembled in the component (i.e. the first and second parts are coaxial), e.g. such that the component is rotationally symmetric about the axis of symmetry. In some embodiments, the first part and / or the second part have a substantially circular cross-section, e.g. in a plane perpendicular to their axis of symmetry. In some embodiments, the diameter of the circular cross-section may vary across the first part and / or the second part (e.g. along the length of the axis of symmetry). In embodiments, the component and / or the chamber is substantially spherical. Thus, in embodiments, the first part and / or the second part is substantially hemi-spherical. In some embodiments the component has an oval cross-section, e.g. in a plane parallel to (e.g. containing) the axis of symmetry of the component. Thus, in some embodiments, the component is substantially ovoidal (egg-shaped) and, e.g., the first part and / or the second part is substantially hemi-ovoidal. An ovoidal component may help to manipulate (e.g. focus) the shockwave as it propagates into the component towards the chamber. Preferably one end of the ovoidal component (e.g. formed by the first part) is more tapered and the other end (e.g. formed by the second part) is more rounded. Preferably the component has a maximum dimension (e.g. the longest dimension (major axis) of the ovoid) that is parallel (e.g. coaxial) with the axis of symmetry of the component. In embodiments, an axis of symmetry of the (e.g. ovoidal) component is co-axial with an axis of symmetry of the (e.g. spherical) chamber. The first part and / or the second part each preferably comprises an inner wall and an outer wall. The outer wall may define the outer surface of the first part and / or the second part respectively (and thus the outer surface of the component, when the first part and the second part are assembled to form the component). In some embodiments, at least a portion of the outer wall and / or the inner wall (of the first part and / or the second part) may be curved. The (e.g. inner wall of the) first part and the (e.g. inner wall of the) second part preferably together define the chamber, e.g. when the first part and the second part are assembled to form the component. The (e.g. inner wall of the) first part and the (e.g. inner wall of the) second part preferably together define the perimeter (surface area) of the chamber, e.g. the entire (surface area) perimeter (e.g. other than the fill lines) of the chamber. The inner walls of the first part and the second part may have any suitable and desired shape. In some embodiments, the inner wall of the first part and / or the second part of the component are substantially rotationally symmetric about an axis (i.e. an axis of symmetry), e.g. an axis through (e.g. the centre of) the component, e.g. through the (e.g. centre of the) chamber. In some embodiments, the inner walls of the first part and the second part share the same axis of symmetry when they are assembled in the component, such that the chamber is substantially rotationally symmetric about the axis of symmetry. In some embodiments, the chamber has a substantially circular cross-section, e.g. in a plane perpendicular to the axis of symmetry. In some embodiments, the diameter of the (e.g. circular) cross-section of the chamber may vary across the chamber (e.g. along the length of the axis of symmetry). The outer walls of the first part and the second part may have any suitable and desired shape. As the outer walls form the (outer) shape of the (first part and the second part of the) component, in embodiments, the outer walls are shaped as outlined herein in relation to the (first part and the second part of the) component. In embodiments, the component is configured to spherically focus an input shockwave, e.g. towards the (e.g. centre of the) chamber. In embodiments, the e.g. first part and / or the second part of the) component has a thickness which is sufficiently large to effectively manipulate an input shockwave. The thickness of the first part, the second part and / or the component may be defined as the shortest distance between the inner wall and the outer wall (e.g. in a plane perpendicular to the axis of symmetry of the component) (e.g. from the chamber to the exterior of the (e.g. first part and / or the second part of the) component). In some embodiments, the diameter of the chamber is approximately half of the diameter of the component (e.g. in a plane perpendicular to the axis of symmetry). In some embodiments, the diameter of the chamber may be more than a quarter of the diameter of the component, in some embodiments, more than a third, in some embodiments, more than a half. In embodiments, the thickness of the (e.g. first part and / or the second part of the) component is similar (e.g. substantially equal) to a maximum dimension (e.g. a diameter) of the chamber. In embodiments, the thickness of the (e.g. first part and / or the second part of the) component is greater than a maximum dimension (e.g. a diameter) of the chamber. In embodiments, an overall volume of the component (e.g. including the volume of the first and second parts, and of the chamber defined by the first and second parts) is significantly greater than the volume of the chamber. In embodiments, the thickness of the (e.g. first part and / or the second part of the) component is greater than 1 / 10,h, e.g. greater than 1 / 5,h, e.g. greater than 3 / 10,hs, e.g. greater than 2 / 5ths, e.g. greater than half of a maximum dimension (e.g. diameter) of the chamber. The (e.g. first part and / or the second part of the) component may any suitable and desired dimensions, e.g. to be determined by the specific application of the component. In one embodiment the (e.g. first part and / or the second part of the) component has a diameter and / or maximum dimension between 0.1 mm and 100 mm, e.g. between 1 mm and 50 mm, e.g. between 2 mm and 10 mm, e.g. approximately 3 mm, 5 mm or 8 mm. In embodiments, the (e.g. first part and / or the second part of the) component has a thickness between 0.025 mm and 25 mm, e.g. between 0.25 mm and 12.5 mm, e.g. between 0.5 mm and 2.5 mm, e.g. approximately 0.75mm, 1.25 mm or 2 mm. In embodiments, the chamber has a maximum dimension (e.g. diameter) between 0.05 mm and 50 mm, e.g. between 0.5 mm and 25 mm, e.g. between 1 mm and 5 mm, e.g. approximately 1.5 mm, 2.5 mm or 4 mm. The component may be formed of any suitable and desired material. The first and second parts of the component may be formed of the same material. In some embodiments, the component is formed from a high Z material. In some embodiments, the component is formed of a metal and / or a metal alloy. For example, the component may be formed of one or more of: gold, tungsten, copper, tantalum and / or an alloy comprising one or more of gold, tungsten, tantalum and / or copper. These materials may be advantageous owing to their high density, high toughness and / or high strength. In some embodiments, the (e.g. first part and / or second part of the) component is configured to (e.g. substantially) manipulate an input shockwave. It will be understood that in order to be configured to manipulate an input shockwave, the (e.g. first part and / or second part of the) component is designed to manipulate a shockwave in a specific and deliberate way. Thus, an element that has some impact on the propagation of a shockwave simply as a result of its construction, but which is not designed or intended to have a specific effect on an input shockwave, will not be understood to be configured to manipulate an input shockwave. In some embodiments, manipulating the shockwave includes accelerating the shockwave, decelerating the shockwave, reflecting portions of the shockwave (e.g. reflecting portions of the shockwave a plurality of times such that portions of the shockwave are superimposed), changing the shape of the shockwave by decelerating and / or accelerating different portions of the shockwave differently (e.g. slowing down a portion of the shockwave which is aligned with the chamber such that the shockwave may curve around the chamber). In some embodiments, the (e.g. first part and / or second part of the) component is configured to spherically focus an input shockwave, e.g. towards the (e.g. centre of the) chamber. The first part and the second part are connected together at the joint, to form the component. Thus, the boundary between the first part and the second part forms the joint. The joint may extend across the thickness of the component (i.e. between the inner and outer walls of the component). The joint may extend across the thickness of the component around the entire perimeter of the component. In some embodiments, the joint may be defined between a bottom surface of the first part and a top surface of the second part. In some embodiments, the joint may be rotationally symmetric (e.g. about the axis of symmetry of the component). For example, taking a cross-section of the component through any plane which contains the axis of symmetry, the shape of the joint is substantially the same in any of these planes, e.g. the joint is a surface of revolution of the cross-sectional path. In some embodiments, taking a cross-section of the component through a plane which contains the axis of symmetry, the joint in the cross-section is a one dimensional shape comprising a curved portion and / or at least one corner. In some embodiments, the joint is a revolution of a one-dimensional shape about the axis of symmetry of the component. Therefore, the joint may be a two-dimensional surface. At least a portion of the joint follows a non-linear path. The path of the joint is the direction of the line or the surface between the chamber and the exterior of the component (e.g. between outer wall and the inner wall of the component), which is formed at the boundary between the first part and the second part. A linear path would be one in which the line or the surface extends in a single direction between the outer wall and the inner wall of the component. For example, a joint that extends only in a radial direction between the outer wall and the inner wall of the component would have a linear path. In this example, in a plane containing the axis symmetry of the component, the joint would appear to be a straight line extending between the outer wall and the inner wall of the component. It will be understood that the term ‘non-linear’ is intended to cover joints that contain at least one change of direction in the path or surface of the joint (e.g. between the outer wall and the inner wall of the component), e.g. curved paths or surfaces, stepped paths or surfaces, paths or surfaces including one or more corners, zig-zag paths, etc.. Paths or surfaces having a plurality of corners may be considered to be labyrinth paths or surfaces. In some embodiments, the joint may comprise a first linear portion (e.g. extending from the inner wall of the component), connected via a first corner to a second linear portion, which is further connected via a second corner to a third linear portion (e.g. extending to the outer wall of the component). In some examples, the first and third linear portions may extend in a substantially radial direction (e.g. perpendicular to the axis of symmetry of the component). In some embodiments, the second linear portion may be substantially perpendicular to the first and / or third linear portions (e.g. parallel to the axis of symmetry of the component). In some embodiments, the first and / or second corners may be (turn through) substantially 90 degrees. In some embodiments, the joint is configured to allow the fluid fuel to be supplied to the chamber. In some embodiments, the joint is configured to provide fluid communication between the exterior of the component and the chamber, e.g. the chamber and the exterior of the component may be fluidly connected via the joint. As such, the joint may provide a path allowing fluid to enter the chamber (e.g. from the exterior of the component). The joint may be configured to allow the fluid fuel to be supplied to the chamber in any suitable and desired way. In some embodiments, the component may be surrounded by a fluid fuel, such that the fluid fuel may flow freely into the chamber. In some embodiments, a pressure differential may be used (e.g. having lower pressure inside the chamber and higher pressure outside the component) to help ensure that fluid fuel flows into the chamber. In some embodiments, the component comprises a fuel fill line. In some embodiments, the joint and / or the fuel fill line are configured to allow the fluid fuel to be supplied to the chamber. In some embodiments, the fuel fill line extends between the outer wall of the component and the inner wall of the component. The fuel fill line may be configured to provide fluid communication between (i.e. to fluidly connect) the exterior of the component and the chamber. In some embodiments, the width (e.g. diameter) of the fuel fill line is less than 100 microns, e.g. less than 50 microns, e.g. less than 10 microns, e.g. less than 5 microns, e.g. less than 2 microns. In embodiments, the fill line has a proximal end, which opens into the chamber (e.g. forms an opening in the inner wall of the component), and a distal end, which opens to the exterior of the component (e.g. forms an opening in the outer wall of the component). In some embodiments, the fuel fill line is formed in the surface of the first part and / or the surface of the second part of the component along the joint. Therefore, in some embodiments, the fuel fill line follows the path of the joint in at least one dimension. The fuel fill line may be formed in any suitable and desired way. In some embodiments, the fuel fill line is formed as a groove in the abutting face of one or both of the first and second parts. For example, the fuel fill line may be etched or machined into the (surface of the) first part and / or the (surface of the) second part. In some embodiments, the first part and / or the second part are formed in a mould which includes a protrusion in the desired shape of the fuel fill line. In some embodiments, the component comprises a plate configured to be sandwiched between the abutting faces of the first and second parts, and wherein the fuel fill line is formed as a groove or slot in the plate. Such embodiments may aid the manufacture of the component, as the fuel fill line may be formed separately from the first and second parts. The plate may be any suitable and desired shape. In some embodiments, the plate may have substantially the same shape as (at least a portion of) the joint. This may help to ensure that the first part and the second part fit together in the desired manner (e.g. maintaining the desired shape of the joint). In some embodiments, the plate is annular. In some embodiments, at least a portion of the fuel fill line follows a non-linear path. A non-linear fuel fill line may be advantageous for at least the same reasons as a non-linear joint. Namely, the fluid fuel may be supplied to the chamber via a fuel fill line, but the non-linear path of the fuel fill line reduces or even eradicates the presence of material jets and / or expelled gas shocks. As such, the interaction of the shockwave with the fluid fuel in the chamber may not be affected by such material jets and / or expelled gas shocks, potentially leading to a more efficient fuel collapse and hence a higher fusion yield. In some embodiments, the component is rotationally symmetric about a central axis. This may help to ensure that the shockwave arrives at the outer perimeter of the chamber (i.e. that it reaches the fuel) at substantially the same time around the entire outer perimeter of the chamber. This may help to ensure that the fuel collapses symmetrically. In some embodiments, at least a portion of the joint follows a spiral path (e.g. in a cross-section through the component, e.g. in a plane parallel to (e.g. containing) the axis of symmetry). In some embodiments, at least a portion of the joint follows an Archimedean spiral path (e.g. in a cross-section through the component, e.g. in a plane parallel to (e.g. containing) the axis of symmetry). At each point on the portion joint that follows the Archimedean spiral path, the joint makes the same angle with the radial direction (i.e. the direction of propagation of an input spherical shockwave). As such, the effect of the joint shape is the same across the whole of the portion of the joint that follows the Archimedean spiral path. In some embodiments, the entire joint may follow an Archimedean spiral path (e.g. in a cross-section through the component, e.g. in a plane parallel to (e.g. containing) the axis of symmetry). In some embodiments, the joint may follow a path that alternates between portions following an Archimedean spiral path of a first chirality and portions following an Archimedean spiral path of a second chirality (e.g. rather than one continuous spiral). This may help to ensure that the first part and the second part may be brought together to form the component. In some embodiments, the portion of the joint following an Archimedean spiral path forms an angle t|) with a radial direction of the component at any point on the portion. In some embodiments, the joint is configured such that | is greater than a first threshold. The first threshold may be the angle at which a material jet no longer reaches the chamber. As such, in such embodiments, the negative impact of a material jet on the fuel collapse may be avoided or (e.g. substantially) reduced. In some embodiments, the first threshold is in the range 30° to 50°. In some embodiments, the joint is configured such that <|> is greater than a second threshold. The second threshold may be the angle at which an expelled gas shock no longer reaches the chamber (e.g. in embodiments where the joint is used to allow fuel to enter the chamber). As such, in such embodiments, the negative impact (e.g. lack of symmetry of the overall shock state) on the fuel collapse may be avoided or (e.g. substantially) reduced. In some embodiments, the joint is configured such that I is smaller than a second threshold. The second threshold may be the angle at which an expelled gas shock no longer reaches the chamber (e.g. in embodiments where the joint is used to allow fuel to enter the chamber). As such, in such embodiments, an expelled gas shock may be allowed to reach the fluid fuel in the chamber. This may be advantageous since the expelled gas shock may act to pre-condition (e.g. pre-heat, or pre-compress) the fluid fuel. In some embodiments, the second threshold is in the range 50° to 60°. In embodiments where the component comprises a fuel fill line, at least a portion of the fuel fill line may follow a spiral path. The spiral path of the fuel fill line may have any one or more of the features discussed above in relation to a spiral path of a joint. It will be appreciated that the fuel fill line will generally follow a onedimensional path, while the joint will generally follow a two-dimensional surface, which, e.g., may be a surface of revolution of a one-dimensional path. In some embodiments, the joint follows a path comprising one or more corners (e.g. in a cross-section through the component, e.g. in a plane parallel to (e.g. containing) the axis of symmetry). In some embodiments, the corner(s) may help to prevent material jetting in the component. When the shock-front reaches the component, low density material may be forced into the joint. However, when the low density material reaches a corner, it is forced to change direction, which introduces turbulence and slows the material down. In examples of a joint having more than one corner, the low density material is slowed down further when it is forced to change direction again at each subsequent corner. Therefore, the corner(s) are configured to slow down the low density material, such that the shock-front arrives at the chamber before the low density material. This helps to ensure that the low density material cannot penetrate the fuel in the chamber before the shockwave reaches the fuel. This helps to avoid introducing an impurity in the fuel, which may have a negative impact on the concentration of energy generated by the shockwave. In embodiments where the joint has been used to allow fuel to enter the chamber, the corner(s) may also help to prevent an expelled gas shock. When the shock-front reaches the component, any residual fuel that is in the joint may be shocked. However, when it reaches a corner, the fuel is forced to change direction, which introduces turbulence and slows the fuel down. In examples of a joint having more than one corner, the fuel is slowed down further when it is forced to change direction again at each subsequent corner. Therefore, the corner(s) are configured to slow down the fuel, such that the shockfront arrives at the chamber before the shocked fuel. This helps to avoid an irregularity in the fuel inside the chamber, which helps to ensure that the fuel collapses symmetrically. In some embodiments, one or more of the one or more corners are approximately 90°. In embodiments where the component comprises a fuel fill line, the fuel fill line may follow a path comprising one or more corners. The corner(s) of the fuel fill line may have any one or more of the features discussed above in relation to the corner(s) of a joint. In some embodiments, at least a portion of the joint follows a path that is parallel to the central axis of the component (e.g. in a cross-section through the component, e.g. in a plane parallel to (e.g. containing) the axis of symmetry). This may help to prevent or reduce the effects of material jetting and / or expelled gas shock because any material jets and / or expelled gas shocks which are generated other (e.g. radial) portions of the joint may be destroyed by a subsequent section that is parallel to the central axis of the component, owing to its geometry with respect to the shockwave. In some embodiments, the joint is configured to change the direction of the fluid fuel as it travels through the joint In some embodiments, this may help to prevent material jetting and / or expelled gas shock in embodiments where the joint has been used to allow fuel to enter the chamber. When the shock-front reaches the component, low density material and / or gas may be forced into the joint. However, forcing the low density material and / or gas to change direction introduces turbulence and slows the material and / or gas down. This helps to ensure that the shock-front arrives at the chamber before the low density material and / or gas and that the low density material and / or gas cannot penetrate the fuel in the chamber before the shockwave reaches the fuel. This helps to avoid introducing an impurity in the fuel, which may have a negative impact on the concentration of energy generated by the shockwave. In some embodiments, the first part and the second part are configured to be moveable relative to one another in at least one direction. In some embodiments, this may be the vertical direction (i.e. in a direction parallel to the central axis of the component). This may help to ensure that the first part and the second part may be brought together to form the component. The first part and the second part may be brought together to form the component in any suitable and desired way. In some embodiments, the first part of the component is lowered onto the second part of the component. In order to facilitate this, the shape of the joint may be configured such that the first and second parts of the component may be brought together along at least one direction. In some embodiments, the first part of the component and the second part of the component are configured to move relative to one another in at least one direction without the top surface of the second part and the bottom surface of the first part coming into contact with one another. In some embodiments, the joint has a thickness (e.g. between the (abutting surfaces of the) first and second parts) of less than 10 microns, preferably less than 5 microns. According to a second aspect of the present invention, there is provided a system comprising: a component as outlined herein; and an apparatus configured to generate a (e.g. quasi-spherical) shockwave to be incident on the component. The component may be arranged to be used with any suitable and desired fuel. In embodiments, the fluid comprises a fuel, e.g. a fuel for nuclear fusion. In embodiments the fluid comprises one or more (e.g. all) of: deuterium gas, liquid deuterium, tritium gas, liquid tritium, deuterium-tritium (DT) gas, and deuteriumtritium (DT) liquid. It will be understood that where used herein, the term “shock-impedance” is intended to mean “'the pressure which must be applied to a medium in order to impart a unit particle velocity to some of the medium” (Henderson, ‘On the refraction of shock waves’, Journal of Fluid Mechanics, Volume 198, January 1989, pages 365-386). This is equal to the product of the shock speed and the density of the un-shocked material. The component may have any suitable and desired dimensions, e.g. to be determined by the specific application of the component. In one embodiment the component has a thickness, diameter and / or maximum dimension between 0.1 mm and 100 mm, e.g. between 1 mm and 50 mm, e.g. between 2 mm and 10 mm, e.g. approximately 3 mm, 5 mm or 8 mm. Certain embodiments of the invention will now be described, by way of example only, with reference to the accompanying drawings, in which: Figure 1 shows a cross-sectional view of a component with a conventional joint; Figure 2 shows a cross-sectional view of a component with a stepped joint; Figure 3 shows an exploded perspective view of a component with a stepped joint; Figure 4 shows a cross-sectional view of a component with a number of stepped portions at the joint; Figure 5 shows a cross-sectional view of a component with a number of sloping portions at the joint; Figure 6 shows a cross-sectional view of a component with a number of spiral portions at the joint; Figure 7 shows an enlarged view of a portion of Figure 6; Figure 8 shows a schematic diagram of a spiral joint whilst a shockwave is propagating through the component; Figure 9 shows an exploded perspective view of a component with a stepped joint and a labyrinth fill line; and Figure 10 shows an exploded perspective view of a component with a stepped joint and a spiral fill line. It will be understood that where used herein, the terms “top”, “bottom”, “up”, “down”, “side”, “base”, “vertical”, “horizontal”, etc. are included for clarity and are intended to refer to the orientation shown in the enclosed Figures. It will be appreciated that, in use, the components and systems may operate in any suitable and desired orientation. It will be understood that each of the components described herein may be configured to be used at part of a nuclear fusion process. As such the fluid fuel mentioned herein may be a fusionable fuel such as deuterium gas. If the fuel is put under a sufficiently high pressure it will collapse, resulting in intense pressures and temperatures being generated in the collapsed fluid fuel, which may be sufficient to initiate fusion. Figure 1 shows a cross-sectional view of a component 2 with a conventional joint 10. In this embodiment, the component 2 is formed from a first part 4 and a second part 6. The first part 4 and the second part 6 fit together at the joint 10 and define a chamber 8 in the component 2. The chamber 8 may be used to contain a fluid (e.g. a gaseous) fuel for use as part of a nuclear fusion process. The first part 4 and the second part 6 fit together at the joint 10 leaving a small gap along the length of the joint 10. In some embodiments, fuel may enter the chambers through the joint 10. Therefore, the joint 10 may provide a means for fluid communication between the outside of the component 2 and the chamber 8. In this embodiment, the joint 10 is a linear radial joint. The joint 10 follows a straight line path from the outer surface of the component 2 to the outer perimeter of the chamber 8. The joint 10 follows a path along the radial direction of the component 2. In this embodiment, the component 2 is rotationally symmetric about the central axis 12 of the component 2. Therefore, if the joint 10 is used to allow fuel to enter the chamber 8, the fuel may enter the chamber 8 through the joint 10 from any point along the perimeter of the component 2. Although in this embodiment, the component 2 is formed from two parts 4, 6 it will be understood that the component 2 may be formed from any suitable and desired number of parts. Therefore, in some embodiments, the component 2 includes a number of joints 10 that are in fluid communication with the chamber 8. The component 2 is used to contain fuel as it undergoes shock from a shockwave. The shockwave impinges upon the component 2 along the radial direction of the component 2. An issue with linear radial joint 10 is that as the shockwave reaches the outer surface of the component 2, lower density material is forced into the linear radial joint 10. This lower density material may comprise lower density material used within the component itself, as well as lower density material from elements of a system in which the component is employed. For example, the component may be suspended in a volume of PMMA (Polymethyl methacrylate). This material forms a jet that travels faster than the shock in the component 2, such that the material jet penetrates the fuel in the volume 8 before the shockwave reaches the fuel. This introduces an impurity in the fuel which has a negative impact on the concentration of energy generated by the shockwave. Another potential issue with linear radial joints 10, in the case of gaseous fuel that has entered the chamber 8 through the linear radial joint 10, is expelled gas shock. The expelled gas shock is a product of the residual fuel which is present in the linear radial joint 10. This fuel is shocked before the shockwave reaches the fuel in the chamber 8, and the gas shock in the linear radial joint 10 is then expelled into the chamber 8, resulting in an irregularity in the fuel inside the chamber. This irregularity may have a negative impact on the properties of the fuel collapse. In embodiments, however, the expelled gas shock may be advantageous, as will be explained below. Figure 2 shows a cross-sectional view of a component 2 with a stepped joint 10. In this embodiment, the joint 10 comprises a first radial section 10a, a vertical section 10b and a second radial section 10c. The radial sections 10a, 10c are substantially perpendicular to the surface of the shock-front. The radial sections 10a, 10c are also substantially perpendicular to the vertical section 10b. The sections 10a-c of the joint 10 are connected and may provide a means for fluid communication between the outside of the component 2 and the chamber 8. The first radial section 10a extends inwardly from the outer surface of the component 2. The first radial section 10a is connected by a corner 10d to the vertical section 10b. The vertical section 10b is connected by a corner 10e to the second radial section 10c, which extends to the outer surface of the chamber 8. In this embodiment, the radial sections 10a, 10c are substantially perpendicular to the vertical section 10b. Hence, corners 10d, 10e are right angles. The corners 10d, 10e may help to prevent material jetting in the component 2. When the shock-front reaches the component 2, low density material may be forced into the joint 10. This low density material may be able to travel along the first radial section 10a at a higher speed than the shock-front. However, when it reaches the first corner 10d, the low density material is forced to change direction, which introduces turbulence and slows the material down. The low density material is slowed down further when it is forced to change direction again at the second corner 10e. Therefore, the corners 10d, 10e are configured to slow down the low density material, such that the shock-front arrives at the chamber 8 before the low density material. This helps to ensure that the low density material cannot penetrate the fuel in the chamber 8 before the shockwave reaches the fuel. This helps to avoid introducing an impurity in the fuel, which may have a negative impact on the concentration of energy generated by the shockwave. In embodiments where the joint 10 has been used to allow fuel to enter the chamber 8, the corners 10d, 10e may also help to prevent an expelled gas shock. When the shock-front reaches the component 2, any residual fuel that is in the joint 10 may be shocked. This fuel may be able to travel along the first radial section 10a at a higher speed than the shock-front. However, when it reaches the first corner 10d, the fuel is forced to change direction, which introduces turbulence and slows the fuel down. The fuel is slowed down further when it is forced to change direction again at the second corner 10e. Therefore, the corners 10d, 10e are configured to slow down the fuel, such that the shock-front arrives at the chamber 8 before the shocked fuel. This helps to avoid an irregularity in the fuel inside the chamber, which helps to ensure that the fuel collapses symmetrically. Figure 3 shows an exploded perspective view of a component 2 with a stepped joint 10. The component 2 of Figure 3 is the same as the component 2 of Figure 2. In this figure, it can be seen that the component 2, including the features of the joint 10, is rotationally symmetric as described above. This may help to ensure that the shock-front arrives at the outer perimeter of the chamber 8 (i.e. that it reaches the fuel) at substantially the same time around the entire outer perimeter of the chamber 8. This may help to ensure that the fuel collapses symmetrically. Figure 4 shows a cross-sectional view of a component 2 with a number of stepped portions at the joint 10. The joint 10 of Figure 4 is similar to that of Figures 2 and 3. However, in this embodiment, the joint 10 comprises a plurality of vertical portions 10b. Each pair of vertical portions 10b are connected by a corner 10d to a radial portion 10a. The joint 10 of Figure 4 operates in a similar manner to that of Figures 2 and 3. If a material jet is formed or expelled gas is shocked, it is forced to change its direction at each of the corners 10d. This change in direction reduces the speed of the material such that the shock-front arrives at the fuel in the chamber 8 before any lower density material and / or the expelled shocked gas. The shape of the joint 10 (including the number of radial portions 10a, vertical portions 10b and / or corners 10d) may be varied in order to ensure that the shockfront arrives at the fuel in the chamber 8 before any low density material and / or the expelled shocked gas. As such, if the component is designed to eradicate any material jet and any expelled gas shock, then a large number of corners 10d should be used. However, if the joint 10 includes a large number of corners 10d, then the joint 10 will be longer and so the overall density of the component will be reduced. This reduction in density may affect how the shockwave propagates through the component and hence potentially affect the successful collapse of the fuel. As such, a compromise between minimising material jets and / or gas shocks, and maintaining sufficient density of the component is found. Figure 5 shows a cross-sectional view of a component 2 with a number of sloping portions at the joint 10. The joint 10 includes a plurality of sloping portions 10f and a plurality of vertical portions 10g. The sloping portions 10f and the vertical portions 10g are alternately connected via a plurality of corners 10h. In some embodiments, the sloping portions 10f may be used as an alternative to the radial portions 10a and vertical portions 10b of Figures 2 and 3. The path length of the joint 10 may be shorter if a sloping portion 10f is used instead of a radial portion 10a and a vertical portion 10b. This may help to increase the overall density of the component, which may help to ensure that the shockwave propagates symmetrically through the component 2. Furthermore, the joint 10 of Figure 5 includes a plurality of corners 10h. These corners 10h may help to reduce material jetting and / or expelled fuel shock. If jets of low density material and / or expelled fuel reaches a corner 10h, it is forced to change direction, which introduces turbulence and slows the material and / or the fuel down. This occurs each time the material and / or the fuel reaches one of the plurality of corners 10h. Therefore, the corners 10h are configured to slow down the material and / or the fuel, such that the shock-front arrives at the chamber 8 before the material and / or the shocked fuel. Figure 6 shows a cross-sectional view of a component 2 with a number of spiral portions at the joint 10. The joint 10 includes a plurality of spiral portions 10i, 10j. The plurality of spiral portions 10i are of a first chirality and the plurality of spiral portions 10k are of a second chirality. The spiral portions 10i and the spiral portions 10j are alternately connected via a plurality of corners 10k. The spiral portions 10i and 10j may help to reduce material jetting and / or expelled gas shock. The plurality of spiral portions 10i, 10j of the joint 10 are formed as sections of an Archimedean spiral (as defined by https: / / mathworld.wolfram.com / ArchimedesSpiral.html). In this embodiment, the joint 10 makes an angle 0 with the outer edge of the chamber 8 (i.e. a tangent 16 to the outer edge of the chamber 8). Owing to the Archimedean spiral shape of the joint 10, at every point on the joint 10, the joint 10 also makes the angle 0 with the tangent to a spherically impinging shockwave along the radius 14 of the component 2. As such, at any given point along the radius 14 of the component 2, the joint 10 makes an angle 4> with the radial direction 14 where ¢ = 0- 90°. The function of the spiral joint 10 will be described with reference to Figure 8, which shows a schematic diagram of a spiral joint 10 whilst a shockwave is propagating through the component 2 towards the chamber 8. For the purposes of the following explanation, the situation depicted by Figure 8 will be described in two dimensions. As such, the joint 10 will be considered to have an inner wall and an outer wall, wherein the inner wall is the wall which is closer to the chamber 8. It can be seen from Figure 8, that as a result of the spiral shape of the joint 10, the shock front 18 is not perpendicular to the central axis of the joint 10, as is the case for a linear radial joint 10. As such, an acute angle is formed at the point 20 at which the shock front 18 contacts the inner wall of the joint 10. As the shock front 18 propagates towards the chamber 8, the point 20 moves down the joint 10 towards the chamber 8. If the point 20 is moving down the joint 10 faster than the material jet, then the jet will not reach the fuel in the chamber 8 until after the shockfront 18 has reached the fuel in the chamber 8, and hence the issues associated with material jetting may be avoided. In embodiments where the joint 10 is used for allowing fuel to enter the chamber 8, the plurality of spiral portions 10i, 10j also help to prevent expelled gas shock. If the point 20 is moving down the joint 10 faster than the expelled gas shock, then no expelled gas shock will reach the fuel in the chamber 8 until after the shock-front 18 has reached the fuel in the chamber 8, and hence any issues associated with an expelled gas shock may be avoided. It will of course be understood that the point 20 is not physical matter that is moving, it is simply the point at which the shock front 18 and the inner wall intersect. The larger the value of 0, the faster the point 20 will move. As such, there is a threshold value of 0 at which the point 20 is travelling faster than the material jet, and a value of 0 at which the point 20 is travelling faster than the expelled gas shock. For the illustrated component 2, these thresholds have been determined using simulations. The threshold value of 0 at which the point 20 is travelling faster than the material jet (and so no material jet enters the chamber 8) is between 120° and 140°, and the threshold value of 0 at which the point 20 is travelling faster than the expelled gas shock is between 140° and 150°. Since ¢ = 0- 90°, if the thresholds are considered as values of 0 (i.e. in terms of the angle made with the radial direction) then the threshold value of 0 at which the point 20 is travelling faster than the material jet (and so no material jet enters the chamber 8) is between 30° and 50°, and the threshold value of 0 at which the point 20 is travelling faster than the expelled gas shock is between 50° and 60° In this embodiment, the joint 10 is formed from a plurality of spiral portions 10i, 10j that alternate between a first chirality and a second chirality, rather than one continuous spiral. This may help to ensure that the first part 4 and the second part 6 may be brought together to form the component 2. For example, in Figure 6 the alternating spiral portions 10i, 10j, form an open surface between the first part 4 and the second part 6. This allows, for example, the first part 4 to be placed on top of the second part 6 to form the component 2. This would not be possible if the joint 10 were formed of one continuous spiral with an angle 9 above the threshold value for material jetting and / or expelled gas shock. Furthermore, the corners 10k may help to reduce material jetting and / or expelled fuel shock. If jets of low density material and / or expelled fuel reaches a corner 10k, it is forced to change direction, which introduces turbulence and slows the material and / or the fuel down. This occurs each time the material and / or the fuel reaches one of the plurality of corners 10k. Therefore, the corners 10k are configured to slow down the material and / or the fuel, such that the shock-front arrives at the chamber 8 before the material and / or the shocked fuel. Figure 7 shows an enlarged view of a portion of Figure 6. Here it can be seen that the plurality of spirals 10i, 10j form an angle 0 to the radius 14 of the component 2. The plurality of spirals 10i, 10j of both a first chirality 10i and a second chirality 10j form the same angle 0 to the radius 14 of the component 2. In some embodiments, the angle 0 may be above the threshold value for material jetting and / or expelled gas shock. This may help to prevent material jets and / or expelled gas reaching the fuel in the chamber 8 before the shock-front. Figure 9 shows an exploded perspective view of a component 2 which is formed of a first part 4 and a second part 6, with a joint 10 in between the first and second parts 4, 6, and the joint 10 comprising a step. In this embodiment, when viewed in a cross-section taken in a plane parallel to the axis 12 of the component 2, the joint 10 comprises a first radial portion 10a, a vertical portion 10b and a second radial portion 10c. The radial portions 10a, 10c are also substantially perpendicular to the vertical portion 10b. In the illustrated embodiment, the vertical portion 10b and the second radial portion 10c are formed by an annular protrusion on the abutting face 22 of the second part 6 and a complementary recess on the abutting face of the first part 4. The fill line 24 of the component 2 is a labyrinth fill line and as such comprises a plurality of radial portions 26, circumferential portions 28, and corners 30. Further, the fill line 24 is formed as a groove in the abutting face 22 of the second part 6. As a result of the vertical portion 10b of the joint 10, the fill line 24 comprises a vertical portion 32. This vertical portion 32 acts in the same way as the circumferential portions 28 since it is parallel to the shock front. Figure 10 shows an exploded perspective view of a component 2 which is a variant of the component 2 of Figure 9. Rather than the labyrinth fill line, the component 2 of Figure 10 comprises a spiral fill line 34. The component 2 of Figure 10 is otherwise identical to the component 2 of Figure 9 and so the description of the joint and abutting faces given in relation to Figure 9 is equally applicable to Figure 10. The component 2 may be manufactured in any suitable and desired way. In some embodiments, the component 2 may be formed over a removable mandrel. For example, the mandrel may be dissolvable or collapsible to allow the mandrel to be removed from the component 2 after it has been formed. In some embodiments, the component 2 may be formed in a mould. For example, the component 2 may be formed of a metal that is cast in a mould. The component 2 may be formed as a single piece or as two or more separate parts 4, 6. If the component 2 is formed as a single piece, it may later be separated (e.g. cut using a machine or a laser) into two or more parts 4, 6. Even if the component 2 is formed in two or more parts 4, 6, at least one surface of the component may be cut (e.g. using a machine or a laser). This may help to ensure that the two or more parts 4, 6 of the component 2 fit together to form a joint 10 of the desired size. In some embodiments, the width of the joint 10 may be on the order of a few microns. Therefore, the surfaces of the two or more parts 4, 6 of the component 2 need to precisely formed or cut to form a joint 10 of the desired size. The two or more parts 4, 6 may be brought together to form the component 2 in any suitable and desired way. In some embodiments, the first part 4 of the component 2 is lowered onto the second part 6 of the component 2. In order to facilitate this, the first part 4 of the component 2 and the second part 6 of the component 2 are configured to move relative to one another in at least one direction. In some embodiments, this is the vertical direction (i.e. in a direction parallel to the central axis 12 of the component 2). The shape of the joint 10 is configured such that the two or more parts 4, 6 of the component 2 may be brought together along at least one direction. In some embodiments, the first part 4 of the component 2 and the second part 6 of the component 2 are configured to move relative to one another in at least one direction 5 without the top surface of the second part 6 and the bottom surface of the first part 6 coming into contact with one another. This may help to ensure that the first part 4 and the second part 6 may be brought together to form the component 2.

Claims

1. A component for containing fluid fuel to be shocked by a shockwave incident on the component, the component comprising;a first part: anda second part;wherein the first part and the second part define a chamber configured to contain the fluid fuel;wherein the first part and the second part are connected at a joint; andwherein at least a portion of the joint follows a non-linear path.

2. A component as claimed in claim 1, wherein the joint is configured to allow the fluid fuel to be supplied to the chamber.

3. A component as claimed in claim 1 or 2, wherein the component is rotationally symmetric about a central axis.

4. A component as claimed in claim 1,2 or 3, wherein at least a portion of the joint follows a spiral path.

5. A component as claimed in claim 4, wherein at least a portion of the joint follows an Archimedean spiral path.

6. A component as claimed in claim 5, wherein the portion of the joint following an Archimedean spiral path forms an angle <|> with a radial direction of the component at any point on said portion.

7. A component as claimed in claim 6, wherein the joint is configured such that t|) is greater than a first threshold.

8. A component as claimed in claim 7, wherein the first threshold is in the range 30° to 50°.

9. A component as claimed in claim 6, 7 or 8, wherein the joint is configured such that I is greater than a second threshold.

10. A component as claimed in claim 6, 7 or 8, wherein the joint is configured such that <|> is smaller than a second threshold.

11. A component as claimed in claim 9 or 10, wherein the second threshold is in the range 50° to 60°.

12. A component as claimed in any one of the preceding claims, wherein the joint follows a path comprising one or more corners.

13. A component as claimed in claim 12, wherein one or more of the one or more corners are approximately 90°.

14. A component as claimed in any one of the preceding claims, wherein at least a portion of the joint follows a path that is parallel to the central axis of the component.

15. A component as claimed in any one of the preceding claims, wherein the joint is configured to change the direction of the fluid fuel as it travels through the joint.

16. A component as claimed in any one of the preceding claims, wherein the first part and the second part are configured to be moveable relative to one another in at least one direction.

17. A component as claimed in any one of the preceding claims, wherein the joint has a thickness of less than 10 microns, preferably less than 5 microns.

18. A system comprising:a component in any one of the preceding claims; andan apparatus configured to generate a shockwave which is incident on the component.AMENDMENTS TO THE CLAIMS HAVE BEEN FILED AS FOLLOWS22 10 2427Claims1. A component for containing fusionable fluid fuel to be shocked by a shockwave incident on the component as part of a nuclear fusion process, the5 component comprising;a first part: anda second part;wherein the first part and the second part define a chamber configured to contain the fluid fuel;10 wherein the first part and the second part are connected at a joint;andwherein at least a portion of the joint follows a non-linear path;wherein the joint is configured to allow the fluid fuel to be supplied to the chamber.

152. A component as claimed in claim 1, wherein the component is rotationally symmetric about a central axis.

3. A component as claimed in claim 1 or 2, wherein at least a portion of the20 joint follows a spiral path.

4. A component as claimed in claim 3, wherein at least a portion of the joint follows an Archimedean spiral path.25 5. A component as claimed in claim 4, wherein the portion of the joint followingan Archimedean spiral path forms an angle <|> with a radial direction of the component at any point on said portion.

6. A component as claimed in claim 5, wherein the joint is configured such that 30 t|) is greater than a first threshold.

7. A component as claimed in claim 6, wherein the first threshold is in the range 30° to 50°.

8. A component as claimed in claim 5, 6 or 7, wherein the joint is configured such that I is greater than a second threshold.

9. A component as claimed in claim 5, 6 or 7, wherein the joint is configured 5 such that <|> is smaller than a second threshold.

10. A component as claimed in claim 8 or 9, wherein the second threshold is in the range 50° to 60°.10 11. A component as claimed in any one of the preceding claims, wherein thejoint follows a path comprising one or more corners.

12. A component as claimed in claim 11, wherein one or more of the one or more corners are approximately 90°.CMCM CM13. A component as claimed in any one of the preceding claims, wherein at least a portion of the joint follows a path that is parallel to the central axis of the component.20 14. A component as claimed in any one of the preceding claims, wherein thejoint is configured to change the direction of the fluid fuel as it travels through the joint.

15. A component as claimed in any one of the preceding claims, wherein the25 first part and the second part are configured to be moveable relative to one another in at least one direction.

16. A component as claimed in any one of the preceding claims, wherein the joint has a thickness of less than 10 microns, preferably less than 5 microns.

17. A system comprising:a component in any one of the preceding claims; andan apparatus configured to generate a shockwave which is incident on the component.

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