Description:TECHNICAL FIELD
[001] The present disclosure generally relates to a Diesel Exhaust Fluid (herein after also referred to as “DEF”) storage tank for vehicles and more particularly, the present disclosure relates to the DEF storage tank having plurality of integrated barriers to attenuate noise of a stored fluid and reduce fluid dead volume within the DEF storage tank.
BACKGROUND
[002] Diesel Exhaust Fluid (DEF) is a urea-based chemical compound designed primarily for use in Selective Catalytic Reduction (SCR) systems in order to reduce levels of nitrogen oxide (NOx) released into the atmosphere from vehicles emission. Availability of DEF meeting the required standard of quality is scarce. Due to this, the automobile manufacturers provide DEF storage tanks with large volumes to store a substantial quantity of the DEF in the tank. The large volume of the DEF storage tank ensures that the DEF needs to be refilled only at scheduled service intervals.
[003] Further, the DEF freezes at temperatures below -11○C and thus to prevent the freezing of the DEF, heating devices are coupled with the DEF storage tank for thawing the fluid. The storage tanks are therefore designed to accommodate the volume expansion of the DEF on freezing. Another constraint in the design of the DEF storage tank pertains to the minimization of dead volume of the DEF stored in the tank. When a vehicle is negotiating a gradient and the fluid level inside the DEF storage tank is very low, the fluid tends to get accumulated on one side of the DEF storage tank. A pump attached to the DEF storage tank for supplying the DEF to the SCR system fails to pump the portion of the fluid accumulated beyond the reach of the pump, rendering a part of volume of the fluid unusable. Thus, the structural design and cross section of the DEF storage tank is a crucial factor for minimizing dead volume of the DEF. Furthermore, the manufacturers are required to ensure that the design of the DEF storage tank facilitates filling system which allows high fill rates without spit backs and provides ease in filling.
[004] Apart from the aforementioned constraints on the design of the DEF storage tank, the manufacturers have an additional challenge to adapt/ accommodate the DEF storage tank in vehicles such as modern passenger cars and sport utility vehicles due to space constraints. It is challenging to adopt the DEF storage tank which has an adequate high fill volume without compromising on the ground clearance requirement and availability of space for interfacing components. This is even more challenging in vehicles having low ground clearance which leaves lesser under-body space to accommodate the DEF storage tank at required height. It is difficult to adopt the DEF storage tank at a rear side of the vehicle since a spare wheel and exhaust muffler of the vehicle occupy most of the available space. It is also challenging to adopt the DEF storage tank at middle portion of some of the vehicles because of flat floors of the vehicle and a user’s preference for lower step-in height of the vehicle.
[005] Moreover, the DEF storage tank along with the fluid creates additional stress on the associated body structure of the vehicle changing the modal behaviour of the structure. Also, ensuring that the vehicle meets crash performance becomes challenging depending upon where the DEF storage tank is packaged in the vehicle. For example, the DEF storage tank may intrude into fuel system components during an event of crash if the DEF storage tank and the fuel system are located close to each other.
[006] Also, in locations where DEF availability is poor, there are high chances of system getting refilled with poor quality DEF which may lead to malfunctioning of the DEF system and the SCR after-treatment system, requiring replacement of the DEF system and SCR after-treatment system, thereby incurring high maintenance cost.
[007] Further, to overcome the space constraint for packaging of the DEF storage tank, a shallow DEF storage tank is designed. However, a major drawback of a shallow DEF storage tank is the sloshing noise of the fluid on acceleration and deceleration of the vehicle and the high dead volume of the fluid. Providing additional mechanisms used in conventional DEF storage tanks is not possible in the shallow DEF storage tanks due to height limitation.
[008] Moreover, conventional design requires development of separate injection moulding tools for multiple baffles and baffle holders along with plastic welding fixture development. Also, it increases manufacturing cycle time. The conventional solution would increase part cost and requires high investments while effectiveness of containing slosh noise is limited.
[009] Therefore, there is a need to design a DEF storage tank which obviates the abovementioned drawbacks of the existing DEF storage tanks.
OBJECTS
[0010] The principal object of an embodiment of this invention is to provide a Diesel Exhaust Fluid (DEF) storage tank with a plurality of integrated barriers within a shell structure of the DEF storage tank to attenuate a noise generated by movement of a fluid against walls of the shell structure during motion of a vehicle.
[0011] Another object of an embodiment of the invention is to provide the DEF storage tank with at least two long barrier profiles disposed within an interior space of the shell structure along a width and across a height of the shell structure, encompassing two front mounting points and two rear mounting points of the DEF storage tank defined on the shell structure, such that the long barrier profiles divide the shell structure into at least three portions and restrict the flow of fluid during acceleration and deceleration of the vehicle.
[0012] Yet another object of an embodiment of the invention is to provide the DEF storage tank in which the shell structure has integrated long barrier profiles, wherein the long barrier profiles are adapted to prevent the fluid from gaining kinetic energy during motion of the vehicle, thereby limiting a velocity of the fluid interacting with the walls of the shell structure, resulting in lower pressure levels within the DEF storage tank.
[0013] Still another object of an embodiment of this invention is to provide the DEF storage tank in which the long barrier profiles are adapted to create a reservoir within a portion of the shell structure to supply the fluid to a pump assembly of the DEF storage tank when the vehicle is negotiating a gradient, therefore reducing a dead volume of the DEF stored in the DEF storage tank.
[0014] Another object of an embodiment of this invention is to provide the DEF storage tank in which the long barrier profiles are provided in conjunction with the two front and two rear mounting points of the DEF storage tank, which stiffens and strengthens the walls of the shell structure, thereby improving a panel mode frequency of the shell structure walls and modal frequency of the DEF storage tank, resulting in improving durability of the DEF storage tank and lowering of noise and vibrations.
[0015] Yet another object of an embodiment of the invention is to provide the DEF storage tank in which a plurality of short barrier profiles are integrated within the shell structure, disposed within the interior of the shell structure and extending inwards from side walls of the shell structure, wherein the short barrier profiles are adapted to restrict the movement of the fluid along the side walls of the shell structure in a portion between the long barrier profiles.
[0016] Still another object of an embodiment of this invention is to provide the shallow DEF storage tank which is adapted to be mounted below a spare wheel housing in the vehicle without compromising on passenger and cabin space, departure angle and ground clearance of the vehicle.
[0017] These and other objects of the embodiments herein will be better appreciated and understood when considered in conjunction with the following description and the accompanying drawings. It should be understood, however, that the following descriptions, while indicating embodiments 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 embodiments herein without departing from the spirit thereof, and the embodiments herein include all such modifications.
BRIEF DESCRIPTION OF DRAWINGS
[0018] The embodiments herein are illustrated in the accompanying drawings, throughout which like reference letters indicate corresponding parts in the various figures. The embodiments herein will be better understood from the following description with reference to the drawings, in which:
[0019] Fig. 1 is a top view of a DEF storage tank showing an upper body of a shell structure of the DEF storage tank, according to embodiments as disclosed herein;
[0020] Fig. 2 is a cross-sectional view of the DEF storage tank showing an interior space of the upper body of the shell structure of the DEF storage tank, according to embodiments as disclosed herein;
[0021] Fig. 3 is a bottom view of the DEF storage tank showing a lower body of the shell structure of the DEF storage tank, according to embodiments as disclosed herein;
[0022] Fig. 4 is another cross-sectional view of the DEF storage tank showing an interior space of the lower body of the shell structure of the DEF storage tank, according to embodiments as disclosed herein;
[0023] Fig. 5A depicts an isometric view of the upper body of the shell structure of the DEF storage tank, according to embodiments as disclosed herein;
[0024] Fig. 5B is an isometric view of the lower body of the shell structure of the DEF storage tank, according to embodiments as disclosed herein;
[0025] Fig. 6A is the cross-sectional view of the upper body of the shell structure depicting a flow of liquid around a plurality of barrier profiles integrated with the shell structure, according to embodiments as disclosed herein;
[0026] Fig. 6B is the cross-sectional view of the lower body of the shell structure depicting the flow of liquid around the plurality of barrier profiles integrated with the shell structure, according to embodiments as disclosed herein;
[0027] Fig. 7 is a cross-sectional side view of the DEF storage tank showing the shell structure and a pump assembly of the DEF storage tank, according to embodiments as disclosed herein;
[0028] Fig. 8A and Fig. 8B are side views of the DEF storage tank depicting a flow/position of the fluid within the shell structure when a vehicle is operating on a surface having a positive gradient, according to embodiments as disclosed herein;
[0029] Fig. 9A and Fig. 9B are side views of the DEF storage tank depicting a flow/position of the fluid within the shell structure when the vehicle is operating on a surface having a negative gradient, according to embodiments as disclosed herein;
[0030] Fig. 10A is a graph depicting kinetic energy of the fluid on interaction with an interior of the shell structure in a conventional DEF storage tank assembly, according to embodiments as disclosed herein;
[0031] Fig. 10B is a graph depicting kinetic energy of the fluid on interaction with an interior of the shell structure of the DEF storage tank, according to embodiments as disclosed herein;
[0032] Figs. 11A and 11Bare graphs representing surface pressure plots for shell structure of a conventional DEF storage tank and the shell structure of the DEF storage tank respectively, according to embodiments as disclosed herein; and
[0033] Figs. 12A and 12Bare modal frequency report for shell structure of a conventional DEF storage tank and the shell structure of the DEF storage tank respectively, according to embodiments as disclosed herein.
DETAILED DESCRIPTION
[0034] The embodiments herein and the various features and advantageous details thereof are explained more fully with reference to the non-limiting embodiments that are illustrated in the accompanying drawings and detailed in the following description. Descriptions of well-known components and processing techniques are omitted so as to not unnecessarily obscure the embodiments herein. The examples used herein are intended merely to facilitate an understanding of ways in which the embodiments herein may be practiced and to further enable those of skill in the art to practice the embodiments herein. Accordingly, the examples should not be construed as limiting the scope of the embodiments herein.
[0035] The embodiments herein achieve a DEF storage tank for a vehicle which includes a plurality of integrated barriers within a shell structure of the DEF storage tank to attenuate a noise generated by movement of a fluid against walls of the shell structure during motion of the vehicle. Further, the embodiments herein achieve the DEF storage tank in which at least two long barrier profiles are disposed within an interior of the shell structure along a width and across a height of the shell structure. The long barrier profiles encompass two front mount points and two rear points of the DEF storage tank defined on the shell structure and are configured to divide the shell structure into three portions and restrict the flow of fluid during acceleration and deceleration of the vehicle. Furthermore, the embodiments herein achieve the DEF storage tank in which the long barrier profiles are adapted to prevent the fluid from gaining kinetic energy during the motion of the vehicle, thereby limiting a velocity of the fluid interacting with the walls of the shell structure, resulting in lower pressure levels within the DEF storage tank. Moreover, the embodiments herein achieve the DEF storage tank in which the long barrier profiles are adapted to create a reservoir within a portion of the shell structure to supply fluid to a pump assembly of the DEF storage tank when the vehicle is negotiating a gradient, therefore reducing a dead volume of the DEF stored in the DEF storage tank.
[0036] The embodiments herein also achieve the DEF storage tank in which the long barrier profiles are provided in conjunction with two front and two rear mounting points of the DEF storage tank, which stiffens and strengthens the walls of the shell structure, thereby improving a panel mode frequency of the walls of the shell structure and modal frequency of the DEF storage tank, resulting in improving durability of the DEF storage tank and lowering of noise and vibrations. Further, the embodiments herein achieve the DEF storage tank which includes a plurality of short barrier profiles integrated with the shell structure and disposed within the interior space of the shell structure extending inwards from side walls of the shell structure, wherein the short barrier profiles are adapted to restrict the movement of the fluid along the side walls of the shell structure in portion between the long barrier profiles. Additionally, the embodiments herein achieve the DEF storage tank which is adapted to be mounted below a spare wheel housing of the vehicle without compromising on passenger and cabin space, departure angle and ground clearance of vehicle. Lower height of tank shell ensures lower visibility of tank from rear to ensure better customer perceived quality. Referring now to the drawings, and more particularly to FIGS. 1 through 10, where similar reference characters denote corresponding features consistently throughout the figures, there are shown embodiments.
[0037] The embodiments herein disclose the DEF storage tank comprising a shell structure which is adapted to store the DEF, a pump assembly, a heating mechanism, a fluid filling system and a DEF outlet mounted on the shell structure. The DEF storage tank further includes a plurality of mounting points defined on the shell structure for facilitating mounting of the DEF storage tank on the body of the vehicle. In an embodiment, the DEF storage tank has a height which ranges from10% to 15 % of a length and width of the DEF storage tank. Fig.7 depicts a cross sectional view of the DEF storage tank (100) showing the shell structure (101) and a pump assembly (200) mounted within the shell structure (101) for supplying the DEF stored in the shell structure (101) to a SCR after-treatment system of the vehicle. In an embodiment, (as shown in Fig.1- Fig.4) the shell structure has a substantially cuboidal shape defining an interior space comprising a front wall (101FW), a rear wall (101BW), two side walls (101LW, 101RW) i.e., a right side wall (101RW) and a left side wall (101LW), an upper wall (101UW) and a lower wall (101W). In an embodiment, the shell structure (101) is formed by blow moulding. In another embodiment, the shell structure (101) comprises an upper body (101UB) and a lower body (101LB) connected to the upper body (101UB). The upper body (101UB) and the lower body (101LB) of the shell structure (101) are fabricated separately and are connected to form a single integrated shell structure (101).
[0038] Fig 1 is a top view of the DEF storage tank (100) showing an upper surface of the shell structure (101) and Fig 3 is a bottom view of the DEF storage tank (100) showing a lower surface of the shell structure (101), according to an embodiment. Fig. 2 is a cross sectional view of the DEF storage tank (100) showing the interior space of the upper body (101UB) of the shell structure (101) and Fig. 4 is another cross-sectional view of the DEF storage tank (100) showing the interior space of the lower body (101LB) of the shell structure (101), according to an embodiment. In an embodiment, as shown in Fig.1 to Fig.4, the DEF storage tank (100) includes a plurality of mounting points (m1, m2, m3, m4, m5, m6) defined on the shell structure (101). Two front mounting points (first mounting point and second mounting point) (m1, m2) are defined towards the front wall (101FW) of the shell structure (101), two rear mounting points (third mounting point and fourth mounting point) (m3, m4)are defined towards the rear wall (101BW) of the shell structure (101), and two other mounting points (fifth mounting point and sixth mounting point) (m5, m6) are defined on members extending from the rear wall (101BW) and right wall (101RW) of the shell structure (101) for facilitating mounting of the DEF storage tank (100) on the body of the vehicle. For the purpose of this description and ease of understanding, six mounting points (m1 through m6) are mentioned herein. However, it is also within the scope of this invention to use any number of mounting points within the spirit of this invention and without otherwise deterring the intended function of the DEF storage tank (100) as can be deduced from this description.
[0039] The DEF storage tank (100) further includes at least two long barrier profiles (102A, 102B) integrated with the shell structure (101). The long barrier profiles (102A, 102B) are defined within the interior space of the shell structure (101), extending along a width of the shell structure (101) and across a height of the shell structure (101) (as shown in Fig. 2 and Fig.4). Further, the long barrier profiles (102A, 102B) are positioned such that the shell structure (101) is divided into at least three portions(P1, P2, P3) (as shown in Fig. 6A and 6B). The long barrier profiles (102A, 102B) are disposed within the shell structure (101) such that the fluid is prevented from gaining kinetic energy when the vehicle is accelerating or decelerating, by restricting the flow of the fluid. Fig. 6A and Fig. 6B depict the flow path of the fluid on interaction with the long barrier profiles (102A, 102B). The long barrier profiles (102A, 102B)also aid in attenuating the sloshing noise generated when the fluid hits the walls of the shell structure (101) since the long barrier profiles (102A, 102B) create a barrier for the movement of the fluid, thereby reducing its kinetic energy.Fig. 10 A is a graph depicting the kinetic energy of the fluid on interaction with the interior walls of the shell structure in a conventional DEF storage tank assembly when the vehicle is accelerated and Fig. 10B shows a graph depicting the reduction in kinetic energy of the fluid in the shallow DEF storage tank (100) on interaction of the fluid with the interior walls of the shell structure (101) when the vehicle is accelerated, as compared to the fluid stored in the conventional DEF storage tank. Figs. 11A is a graph representing surface pressure plot for shell structure of a conventional DEF storage tank. As is apparent from Fig. 11B, which is a graph representing surface pressure plot for shell structure of the DEF storage tank according to embodiments of the present invention, the surface pressure is decreased. Further, Figs. 12A and 12B are modal frequency report for shell structure of a conventional DEF storage tank and the shell structure of the DEF storage tank according to embodiments of the present invention, respectively.
[0040] In an embodiment, the DEF storage tank (100) includes a first long barrier profile (102A) disposed towards the front wall (101FW) of the shell structure (101) and a second long barrier profile (102B) disposed towards the rear wall (101BW) of the shell structure (101). The first long barrier profile (102A) encompasses the two front mounting points (m1, m2) and extends longitudinally along the width of the shell structure (101). The second long barrier profile (102B) encompasses the two rear mounting points (m3, m4) and extends longitudinally along the width of the shell structure (101). Both the first long barrier profile (102A) and second long barrier profile (102B) are disposed such that ends of the long barrier profiles (102A, 102B) do not touch the side walls (101LW, 101RW) of the shell structure (101). Further, both the long barrier profiles (102A, 102B) are disposed across the height of the shell structure (101) such that the long barrier profiles (102A, 102B) are in an abutting relation with the upper wall (101UW) and the lower wall (101W) of the interior space of the shell structure (101).
[0041] Further, according to an embodiment, the DEF storage tank (100) includes a plurality of short barrier profiles (103L, 103R) integrated with the shell structure (101) and disposed within the interior space of the shell structure (101) at predetermined positions. The short barrier profiles (103L, 103R)extend inwards from the side walls (101LW, 101RW) of the shell structure (101). Further the short barrier profiles (103L, 103R) are adapted to restrict the flow of the fluid when the fluid comes in contact with the side walls (101LW, 101RW) of the shell structure (101). In an embodiment, an end of each of the short barrier profiles(103L, 103R) is in an abutting relation with the respective side wall (101LW, 101RW) of the shell structure (101) and another end of the short barrier profiles (103L, 103R) extends towards a middle portion of the shell structure (101) up to a predetermined length. In an embodiment, the plurality of short barrier profiles (103L, 103R) comprises two short right barrier profiles (103R) extending inward from the right side wall (101RW) of the shell structure (101), and one short left barrier profile(103L) extending inwards from the left side wall (101LW) of the shell structure (101). The short barrier profiles (103L, 103R) are positioned along the side walls (101LW, 101RW) in a portion defined between the two long barrier profiles (102A, 101B). The short barrier profiles (103L, 103R) are adapted to restrict the flow of the fluid when the fluid comes in contact with the side walls (101LW, 101RW) of the shell structure (101).
[0042] In an embodiment of the invention, wherein the shell structure (101) comprises the upper body (101UB) and the lower body (101LB), as shown in Fig. 5A and 5B, the long barrier profiles (102A,102B) comprise an upper half portion (102AU,102BU) integrated with the upper body (101UB) of the shell structure (101), and a lower half portion (102AL, 102BL) integrated with the lower body (101LB) of the shell structure (101). Similarly, the short barrier profiles (103L, 103R) are integrated into two halves, wherein an upper half (not shown) is integrated with the upper body (101UB) and the lower half (not shown) is integrated with the lower body (101LB) of the shell structure (101).
[0043] Further, as shown in Figs. 8A-9B, the long barrier profiles (102A, 102B) integrated with the shell structure (101) are adapted to function as a reservoir to supply fluid to a pump assembly (200) coupled to the DEF storage tank (100) when the vehicle is negotiating a gradient. Furthermore, the long barrier profiles (102A, 102B) and the short barrier profiles (103L,103R) are adapted to strengthen the walls (101FW, 101BW, 101LW, 101RW) of the shell structure (101) and lower the noise and vibrations generated within the shell structure (101). In an embodiment, the long barrier profiles (102A, 102B) and the short barrier profiles (103L, 103R) are integrated with the shell structure (101) by blow moulding. In an embodiment, the DEF storage tank (100) is adapted to be mounted below a spare wheel housing of the vehicle.
[0044] The technical advantages achieved by the embodiments disclosed herein include providing DEF storage tank with barrier profiles integrated with the shell structure of the tank which facilitates in attenuating noise generated by the fluid when the fluid interacts with the walls of the tank/ shell structure by regulating the flow of the fluid and preventing the fluid from gaining kinetic energy, creating a local reservoir within the storage tank to supply the fluid to the DEF storage tank pump when the vehicle is negotiating a gradient, therefore minimizing the dead volume of the fluid, stiffening and strengthening of walls of the shell structure resulting in improved modal frequency and panel mode frequency, ease of manufacturing and eliminating need of extra parts.
[0045] The foregoing description of the specific embodiments will so fully reveal the general nature of the embodiments herein that others can, by applying current knowledge, readily modify and/or adapt for various applications such specific embodiments without departing from the generic concept, and, therefore, such adaptations and modifications should and are intended to be comprehended within the meaning and range of equivalents of the disclosed embodiments. 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 embodiments herein have been described in terms of preferred embodiments, those skilled in the art will recognize that the embodiments herein can be practiced with modification within the spirit and scope of the embodiments as described herein.
, Claims:We claim,
1. A Diesel Exhaust Fluid (DEF) storage tank (100) for a vehicle, the DEF storage tank (100) comprising:
a shell structure (101) adapted to store a predefined volume of diesel exhaust fluid; and
at least two long barrier profiles(102A,102B) disposed in an interior space of the shell structure (101) at predetermined positions, the long barrier profiles (102A,102B) extend along a width of the shell structure (101) and across a height of the shell structure (101),
wherein the long barrier profiles (102A,102B) are configured to:
divide the shell structure (101) into at least three portions (P1, P2, P3); and
restrict a flow of the fluid stored in the shell structure (101) to prevent the fluid from gaining kinetic energy during an acceleration and deceleration of the vehicle.

2. The DEF storage tank (100) as claimed in claim 1, wherein,
a first long barrier profile (102A) is disposed towards a front wall(101FW) of the shell structure (101), encompassing a first mounting point (m1) and a second mounting point (m2) defined in the shell structure (101) towards the front wall (101FW); and
a second barrier profile (102B) is disposed towards a rear wall(101BW) of the shell structure (101), encompassing a third mounting point (m3) and a fourth mounting point (m4) defined in the shell structure (101) towards the rear wall (101BW).

3. The DEF storage tank (100) as claimed in claim 1, wherein the DEF storage tank (100) comprises a plurality of short barrier profiles (103L,103R) integrated with the shell structure (101) and disposed within the interior space of the shell structure (101) at predetermined positions, extending inwards from a left side wall and a right side wall(101LW, 101RW) of the shell structure (101), wherein
the short barrier profiles (103L, 103R) are adapted to restrict the flow of the fluid, when the fluid comes in contact with the left side wall and the right side wall (101LW, 101RW) of the shell structure (101).

4. The DEF storage tank (100) as claimed in claim 3, wherein the plurality of short barrier profiles (103L, 103R) comprises:
at least two short right barrier profiles (103R) extending inwards from the right-side wall (101 RW) of the shell structure (101); and
at least one short left barrier profile (103L) extending inwards from the left-side wall (101LW) of the shell structure (101),
wherein,
each of the short right barrier profiles (103R) and the short left barrier profile (103L) are integrated with the shell structure (101) and disposed within the interior space of the shell structure (101) at predetermined positions; and
the two short right barrier profiles (103F) and the short left barrier profile (103L) are adapted to restrict the flow of the fluid, when the fluid comes in contact with the right-side wall (101RW) and the left-side wall (101LW) of the shell structure (101).

5. The DEF storage tank (100) as claimed in claim 4, wherein the two short right barrier profiles (103R) and the short left barrier profile (103L) are positioned between the at least two long barrier profiles (102A, 102B) such that the short barrier profiles (103L,103R) restrict the flow of the fluid along the side walls (101LW,101RW) of the shell structure (101).

6. The DEF storage tank (100) as claimed in claim 1, wherein the shell structure (101) comprises an upper body (101UB) and a lower body (101LB)integrated with the upper body (101UB) thereby forming a unitary shell structure (101).

7. The DEF storage tank (100) as claimed in claim 6, wherein each of the long barrier profiles (102A,102B) comprise an upper half portion (102AU,102BU) integrated with the upper body (101UB) of the shell structure (101), and a lower half portion (102AL, 102BL) integrated with the lower body (101LB) of the shell structure (101).

8. The DEF storage tank (100) as claimed in claim 1, wherein the long barrier profiles(102A, 102B) integrated with the shell structure (101) are adapted to function as a reservoir to supply fluid to a pump assembly (200) coupled to the DEF storage tank (100) when the vehicle is negotiating a gradient.

9. The DEF storage tank (100) as claimed in claim 5, wherein the long barrier profiles (102A, 102B) and the short barrier profiles (103L,103R) are adapted to strengthen the walls (101FW, 101BW, 101LW, 101RW) of the shell structure (101) and lower noise and vibration generated within the shell structure (101).

10. The DEF storage tank (100) as claimed in claim 5, wherein the long barrier profiles (102A, 102B) and the short barrier profiles (103L, 103R) are integrated with the shell structure (101) by blow moulding; and
the DEF storage tank (100) is adapted to be mounted below a spare wheel housing of the vehicle.