FORM 2
THE PATENTS ACT 1970
[39 OF 1970]
AND
THE PATENTS RULES, 2003
COMPLETE SPECIFICATION [See section 10; rule 13]
TITLE OF THE INVENTION REDUCTION OF SLOSHING OF LIQUIDS IN TANKS
APPLICANT(s)
TATA MOTORS PASSENGER VEHICLES LIMITED
an Indian Company Floor 3, 4, Plot-18, Nanavati Mahalaya,
Mudhana Shetty Marg, BSE, Fort, Mumbai City, Mumbai – 400 001,
Maharashtra, India.
PREAMBLE TO THE DESCRIPTION
The following Specification particularly describes the invention and the manner in which it is to be performed.

FIELD OF THE INVENTION
[0001] The present invention relates to tanks storing liquids, and more specifically, related to reduction of sloshing of liquids in such tanks.
BACKGROUND OF THE INVENTION
[0002] A tank may be used to store a liquid for various purposes. For example, an automotive vehicle, hereinafter referred to as a vehicle, may include a fuel tank to store fuel, such as diesel or gasoline. When the tank undergoes a change in speed (e.g., when a vehicle having a fuel tank accelerates or decelerates), the liquid in the tank may hit against the walls of the tank. Further, a portion of the liquid that hits the tank may fall on the remainder of the liquid in the tank. Such hitting and falling of the liquid may be referred to as sloshing.
[0003] Sloshing is an undesired phenomenon in several cases. For example, a liquid hitting a wall of a tank with a large force may damage the wall. As another example, in the case of vehicles carrying large amounts of liquids, such as tanker trucks, sloshing may cause the vehicles to lose stability and even to topple. Further, a sloshing noise may be generated from a fuel tank of a vehicle during acceleration and braking of the vehicle. The sloshing noise may be audible to occupants of the vehicle, causing annoyance or anxiety to the occupants.
[0004] Conventional mechanisms used for reduction of sloshing are either inadequate in solving the problem or are expensive. A need exists for an efficient and cost-effective solution to reduce sloshing.
SUMMARY OF THE INVENTION
[0005] A tank for holding a liquid includes a baffle disposed in the tank to reduce sloshing of the liquid in the tank. The baffle has a spiral shape and has a

plurality of openings on a surface thereof. The liquid stored in the tank is to move from one side of the tank to another side of the tank through the openings.
BRIEF DESCRIPTION OF DRAWINGS
[0006] The features, aspects, and advantages of the subject matter will be better understood with regard to the following description, and accompanying figures. The use of the same reference number in different figures indicates similar or identical features and components.
[0007] Fig. 1 illustrates schematically illustrates a tank that is used to store a liquid, according to an implementation of the present subject matter.
[0008] Fig. 2(a) illustrates a tank, according to an implementation of the present subject matter.
[0009] Fig. 2(b) schematically illustrates offsets between openings on various layers of a baffle, according to an implementation of the present subject matter.
[0010] Fig. 3 illustrates a vehicle in which sloshing is to be reduced, according to an implementation of the present subject matter.
DETAILED DESCRIPTION OF INVENTION
[0011] The present subject matter relates to reduction of sloshing of liquids in tanks. Using techniques of the present subject matter, sloshing of liquids can be significantly reduced in tanks.
[0012] In accordance with an implementation of the present subject matter, a tank for holding a liquid includes a baffle disposed in the tank. The tank may be, for example, a fuel tank of a vehicle. In accordance with the example, the liquid

stored in the tank may be a fuel that is used for running the vehicle. The baffle has a spiral shape and has a plurality of openings on a surface thereof. The baffle is positioned in the tank such that the liquid stored in the tank is to move from one side of the tank to another through the openings. For instance, the baffle may extend between a first side of the tank and a second side of the tank opposite the first side. Consequently, when the liquid is to move from the first side to the second side, the liquid is to pass through the openings on the surface of the baffle.
[0013] Since the liquid flowing from one side of the tank to another is to pass through the openings of the baffle, the liquid is to hit against the various layers of the spiral-shaped baffle, when moving between the sides. Such hitting reduces kinetic energy of the liquid, and significantly slows down the liquid. Therefore, the liquid that hits against a wall of the tank does so with a low speed. Accordingly, sloshing is significantly reduced in the tank.
[0014] In an implementation, the openings on one layer of the baffle are offset from the openings on the adjacent layer of the baffle. Accordingly, liquid passing through openings on one layer of the baffle has to change its direction to pass through the openings on the next layer. Therefore, the liquid has to undergo multiple changes of direction before hitting against a wall of the tank. The multiple changes of direction further reduces the kinetic energy of the liquid.
[0015] In an example, the baffle may extend substantially across an entire length of the tank. For example, an outer diameter of the baffle may be substantially equal to the length of the tank. Accordingly, any lengthwise movement of the liquid in the tank is impeded by the baffle, thereby significantly reducing sloshing of the liquid.
[0016] The implementations herein and the various features and advantageous details thereof are explained more fully with reference to the non-limiting

implementations that are illustrated in the accompanying drawings and detailed in the following description. It should be understood, however, that the following descriptions, while indicating preferred implementations and numerous specific details thereof, are given by way of illustration and not of limitation. Many changes and modifications may be made within the scope of the implementations herein without departing from the spirit thereof, and the implementations herein include all such modifications. The examples used herein are intended merely to facilitate an understanding of ways in which the implementations herein can be practiced and to further enable those skilled in the art to practice the implementations herein. Accordingly, the examples should not be construed as limiting the scope of the implementations herein.
[0017] In the below description, a tank is explained with reference to a fuel tank. However, it is to be understood that the implementations of the present subject matter can also be used for other types of tanks. For example, techniques of the present subject matter can be used in tanks placed in tanker trucks that are used for conveying large quantities of liquids.
[0018] Descriptions of well-known components and processing techniques are omitted so as to not unnecessarily obscure the implementations herein. Also, the various implementations described herein are not necessarily mutually exclusive, as some implementations can be combined with one or more other implementations to form new implementations.
[0019] Referring now to the drawings, where similar reference characters denote corresponding features consistently throughout the figures, there are shown preferred implementations. Further, for the sake of simplicity, and without limitation, the same numbers are used throughout the drawings to reference like features and components. The implementations herein will be better understood from the following description with reference to the drawings.

[0020] Fig. 1 illustrates schematically illustrates a tank 100 that is used to store a liquid, according to an implementation of the present subject matter. Here, the tank 100 is shown as open from the top to illustrate the inside of the tank 100. The tank 100 may include a plurality of walls, such as walls 101-1, 101-2, 101-3, and 101-4. The tank 100 may be, for example, a fuel tank of a vehicle (not shown in Fig. 1). In accordance with the example, the liquid stored in the tank may be a fuel, such as diesel or gasoline, that is used for driving the vehicle. The vehicle may be, for example, a commercial vehicle, such as a truck, or a passenger vehicle, such as a car.
[0021] In some cases, the tank 100 may undergo changes in speed. For example, the vehicle having the tank 100 may be accelerated or decelerated. In such cases, the liquid in the tank 100 may tend to move due to its inertia and may tend to hit a wall of the tank 100. Such a movement of the liquid, if unimpeded, may cause a significant amount of sloshing, which in turn may cause damage to the walls of the tank, noise, and reduced stability of the vehicle.
[0022] To reduce sloshing in the tank 100, a baffle 102 may be disposed in the tank 100. The baffle 102 may be spiral-shaped. In an implementation, the baffle 102 may be made from sheet metal. For instance, a sheet of metal may be rolled in the shape of a spiral to form the baffle 102. In other implementations, the baffle 102 may be made of plastic or fibre. In an example, the baffle 102 may be a spiral spring.
[0023] The baffle 102 may include a plurality of layers 104-1, 104-2, …, 104-n (collectively referred to as layers 104). The layers 104 may be centred around an axis 105 of the baffle 102. Further, the outermost layer 104-n of the baffle 102 may face the walls of the tank 100. In an example, the axis 105 may extend in a height direction of the tank 100, as illustrated. Further, the axis 105 may be substantially equidistant from opposite walls of the tank 100. For example, a distance between the wall 101-1 and the axis 105 may be substantially equal to

the distance between the axis 105 and the wall 101-3. Alternatively or additionally, a distance between the wall 101-2 and the axis 105 may be substantially same as the distance between the axis 105 and the wall 101-4. Accordingly, the axis 105 may be close to, or coincide with, a centre of the tank 100 in the lengthwise and/or width-wise directions of the tank 100.
[0024] The baffle 102 may include a plurality of openings on a surface of the baffle 102. For example, multiple openings may be provided on each of the layers 104. Each opening may extend through a thickness of the surface of the baffle 102. Each opening may have one of a variety of shapes, such as circular, rectangular, and triangular. To flow from one side of the tank, such as side 106, to another side, such as side 108, the liquid is to pass through the openings on the surface of the baffle 102. For instance, the plurality of layers 104 divide the tank 100 into a plurality of chambers, such as chambers 110-1, 110-2, 110-3, …. Accordingly, the liquid that is to move across the tank 100 is to move from one chamber to another, through the openings provided on the various layers 104.
[0025] During movement of the liquid from one chamber to another for moving in the tank 100, the liquid hits against the layers 104 of the baffle 102. The hitting against the layers reduces the kinetic energy of the liquid. Thus, before the liquid reaches a wall of the tank 100 and hits against the wall, the liquid hits against a plurality of layers 104 of the baffle 102. For example, when the liquid near a centre of the tank 100 travels towards a wall 101-2 of the tank 100, the liquid hits against the layers 104-1, 104-2, …, before eventually hitting against the wall 101-2. Such hitting against multiple layers significantly reduces the kinetic energy of the liquid. Thus, the liquid hits the wall 101-2 with a low kinetic energy, thereby significantly reducing the sloshing.
[0026] In an example, the baffle 102 may be supported, such as mounted, on a floor 116 of the tank 100 and may extend towards a roof (not shown in Fig. 1) of the tank 100. In another example, the baffle 102 may be supported on the roof

of the tank 100 and may extend towards the floor 116. In a further example, the baffle 102 may be supported on one or more walls 100 of the tank 100. Further, the baffle 102 may have a height that is at least 60% of a height of the tank 100. For instance, the height of the baffle 102 may be in a range of 60-95% of height of the tank 100. Accordingly, liquid flowing at any height of the tank 100 may flow through the baffle 102.
[0027] Further, in an example, the baffle 102 may span substantially across an entire length and/or width of the tank 100. For example, an outer diameter ‘D’ of the baffle 102 may be at least 70% of a length and/or width of the tank 100. Accordingly, a liquid that is to flow from any portion of the tank 100 to another portion of the tank 100 may be forced to flow through the baffle 102. Therefore, the liquid at any portion of the tank 100 is to flow through the baffle 102 before hitting a wall of the tank 100. Thus, kinetic energy of liquid hitting the wall of the tank 100, regardless of which part of the tank 100 the liquid originated from, is less.
[0028] The baffle 102 may be attached to the tank 100 using a variety of joining methods. The joining method may depend on the materials with which the tank 100 and the baffle 102 are made. For example, if the baffle 102 and the tank 100 are each made of a metal, they may be attached by welding. If the baffle 102 and the tank 100 are made of a plastic or fibre, they may be attached to each other using fasteners.
[0029] Fig. 2(a) illustrates the tank 100, according to an implementation of the present subject matter. Here, the roof and the walls of the tank 100 are not illustrated. As illustrated, the outermost layer 104-n and the penultimate layer 104-n-1 immediately preceding the outermost layer 104-n include a plurality of openings. In an implementation, openings provided on one layer may be offset from openings provided on an adjacent layer. In other words, openings provided on one layer may be unaligned with respect to openings on an

immediately adjacent layer. For example, the openings on the outermost layer 104-n may be offset from the openings 202-n-1 provided on the penultimate layer 104-n-1. The offset between openings on adjacent layers is schematically illustrated in Fig. 2(b).
[0030] In the figures, each layer of the baffle 102 is illustrated as having a substantially circular shape. However, the layers may have a different shape depending on a shape of the tank. For example, if the shape of the tank is rectangular, with the length of tank being greater than the width, the layers may have a substantially elliptical shape, with the major diameter of the layers extending in the length direction of the tank and the minor diameter extending in the width direction. Thus, the shape of the various layers may differ depending on the shape of the tank, such that the baffle covers a substantial area of the tank.
[0031] Fig. 2(b) schematically illustrates offsets between openings on various layers of the baffle 102, according to an implementation of the present subject matter. Here, the various layers of the baffle 102 are shown as planar layers placed parallel to each other to illustrate the offset between the openings on the various layers. As illustrated, the openings on one layer, such as the first layer 104-1, are offset from the openings on the immediately adjacent layer, such as the second layer 104-2.
[0032] Since openings on one layer are offset from those in the adjacent layer, liquid entering through the openings on one layer is to change its direction before passing through the adjacent layer. For example, liquid entering through the openings on the first layer 104-1 is to change its direction before passing through the openings on the second layer 104-2. In this manner, the liquid passing through the various layers of the baffle 102 changes its direction multiple times when passing through the layers. The repeated changes in direction of the liquid significantly slows down the liquid, thereby significantly

reducing the kinetic energy of the liquid. Such a reduction in the kinetic energy further reduces the sloshing.
[0033] In the above explanation, a tank is shown as having a single baffle. However, a tank may be provided with multiple baffles. The number of baffles in a tank may be determined based on the dimensions of the tank. For example, if the tank is of a rectangular shape with the length of the tank being greater than its width, two baffles offset from each other in a length direction of the tank may be provided. Further, the different baffles provided in the tank may have different shapes and/or sizes. In an implementation, a baffle provided in the tank may be coupled to another baffle provided in the tank. For example, the outermost layers of two baffles may be joined with each other, such as by welding.
[0034] Fig. 3 illustrates a vehicle 300 in which sloshing is to be reduced, according to an implementation of the present subject matter. The vehicle 300 may include a tank 302 to store a liquid. The tank 302 corresponds to the tank 100. In an example, the tank 302 may be a fuel tank that is to store a fuel used for running the vehicle 300. In another example, the tank 302 may be one that is used for storing another liquid used for performing another function in the vehicle 300. For instance, the tank 302 may be a urea tank that is to store urea, which may be used for reducing NOx emissions of the vehicle 300. In another example, the vehicle 300 may be a tanker truck used for conveying large amounts of liquids, and the tank 302 may be tank of the tanker truck.
[0035] The tank 302 may have a baffle 304 disposed therein. The baffle 304 may correspond to the baffle 102. Accordingly, the baffle 304 may help in reducing sloshing of the liquid in the tank 302. The baffle 304 may have a spiral shape and may have a plurality of openings on a surface thereof. The liquid stored in the tank 302 is to move from one side of the tank 302 to another side of the tank through the openings. In an example, the baffle 304 may have a

plurality of layers, such as the layers 104. Further, openings on one layer may be offset from openings on an adjacent layer, as explained with reference to Figs. 2(a) and 2(b).
[0036] The present subject matter provides a simple and effective technique for reducing sloshing in vehicles. Thus, the noise caused due to the sloshing can be reduced, thereby enhancing driving experience of occupants of the vehicle. Further, damage to fuel tanks and other liquid tanks used in the vehicle can also be reduced. Still further, loss of stability of a vehicle due to the sloshing can be significantly reduced, thereby preventing toppling of the vehicle.
[0037] Since the thickness of the baffle is small, the volume occupied by the baffle is less. Therefore, the volume available in the tank for holding liquid is not significantly reduced.
[0038] The foregoing description of the specific implementations will so fully reveal the general nature of the implementations herein that others can, by applying current knowledge, readily modify and/or adapt for various applications without departing from the generic concept, and, therefore, such modifications and adaptations should and are intended to be comprehended within the meaning and range of equivalents of the disclosed implementations. It is to be understood that the phraseology or terminology employed herein is for the purpose of description and not of limitation. Therefore, while the implementations herein have been described in terms of preferred implementations, those skilled in the art will recognize that the implementations herein can be practiced with modification within the spirit and scope of the implementations as described herein.

We Claim:
1. A tank for holding a liquid, the tank comprising:
a baffle disposed in the tank to reduce sloshing of the liquid in the tank, the baffle having a spiral shape and having a plurality of openings on a surface thereof, wherein the liquid stored in the tank is to move from one side of the tank to another side of the tank through the openings.
2. The tank as claimed in claim 1, wherein the baffle has a plurality of layers such that the plurality of layers divides the tank into a plurality of chambers.
3. The tank as claimed in claim 2, wherein each layer of the baffle has a substantially circular or elliptical shape.
4. The tank as claimed in claim 1, wherein the baffle has a plurality of layers, and wherein openings on one layer are offset from openings on an adjacent layer.
5. The tank as claimed in claim 1, wherein the baffle is supported on a floor, a roof, or a wall of the tank.
6. The tank as claimed in claim 1, wherein an axis of the baffle is substantially equidistant from opposite walls of the tank.
7. The tank as claimed in claim 1, wherein a height of the baffle is at least 60% of a height of the tank and wherein an outer diameter of the baffle is at least 70% of a length of the tank.
8. A vehicle comprising:
a tank for storing a liquid, the tank comprising:

a baffle disposed in the tank to reduce sloshing of the liquid in the tank, the baffle having a spiral shape and having a plurality of openings on a surface thereof, wherein the liquid stored in the tank is to move from one side of the tank to another side of the tank through the openings.
9. The vehicle as claimed in claim 8, wherein the tank is a fuel tank of the vehicle.
10. The vehicle as claimed in claim 8, wherein the baffle has a plurality of layers, and wherein openings on one layer are offset from openings on an adjacent layer.