Claims:[0044] Claims:
We claim:
1. A fan shroud assembly (100) comprising:
a) a frame front opening for air inlet from a radiator (102) and a frame back opening to receive the fan assembly (103), wherein the fan assembly (103) further comprises a plurality of blades and a fan drive shaft for engine cooling purpose;
b) a frame assembly (101) to provide structural support for attachment of the fan assembly (103) to the radiator (102), wherein a protruded bell mouth is formed around corner edges (101a) of the frame assembly (101) to increase the mass flow rate through the radiator (102).

2. The fan shroud assembly (100) as claimed in claim 1, wherein the corner gap between the radiator (102) plane and the frame front opening is increased by using a protruded bell mouth at the corners (10a) of the frame assembly (101).

3. The fan shroud assembly (100) as claimed in claim 2, wherein the corner gap between the radiator (102) plane and the frame front opening is increased to improve mass air flow rate through the radiator (102).

4. The fan shroud assembly (100) as claimed in claim 2, wherein an optimized guide curve (104) is formed between the frame assembly (101) front opening and the radiator (102) plane.

5. The fan shroud assembly (100) as claimed in claim 4, wherein the optimized guide curve (104) provides funneling effect thereby resulting in low air pressure towards the air inlet region.

6. The fan shroud assembly (100) as claimed in claim 5, wherein the optimized guide curve (104) is a Bezier curve.

, Description:[0001] PREAMBLE TO THE DESCRIPTION:
[0002] The following specification particularly describes the invention and the manner in which it is to be performed:
[0003] DESCRIPTION OF THE INVENTION
[0004] Technical field of the invention
[0005] The present invention relates to a fan shroud assembly and more particularly relates to a fan shroud assembly with improved mass air flow rate through the radiator.
[0006] Background of the invention
[0007] In general, an engine in an automotive vehicle is cooled by liquid coolant which is pumped either by a liquid-to-air heat exchanger or a radiator. Further, the location of these heat exchangers is typically in front of the vehicle, so that high pressure due to forward motion of the vehicle may cause air to move through them. However, to assure that sufficient air moves through the heat exchangers where cooling requirements are severe or when the vehicle is not moving, a fan assembly is fitted either upstream or downstream of the heat exchangers. Here, the fan assembly typically includes a fan and a shroud which surrounds the fan to guide air between the heat exchanger and the fan assembly.
[0008] However, when the vehicle is operating in stop-and-go conditions or when the vehicle is standing still, the effectiveness of air cooling drops considerably because the volume of air passing through the radiator is diminished. To overcome the above-mentioned drawbacks fan shrouds with various geometries were introduced.
[0009] For instance, the patent document WO2001096746A1 (referred herein as ‘746) discloses an automotive fan assembly with flared shroud and with conforming blade tips to conform to the shape of the inlet of the flared shroud, to increase the air flow rate and to reduce the noise level of the shroud fan combination.
[0010] Similarly, a Korean patent document KR100707782B1 (referred herein as ‘782) discloses a fan shroud assembly for a vehicle to reduce ventilation resistance and noise and to increase air flow by forming a bell mouth at a shroud hood. Further, to reduce ventilation resistance a protruded bell mouth as disclosed in ‘782 is formed at an air inlet of the fan of the hood along the circumferential direction, to guide the air flow. Here, the bell mouth is positioned higher than the end of the air inlet of the fan to reduce ventilation resistance.
[0011] Another Korean patent document KR20090040560A (referred herein as ‘560) discloses an automobile fan shroud assembly comprising a cooling fan and a shroud to attach the cooling fan to a vehicle structure. Further, a square shaped sound absorbing material is formed in the border of the shroud to reduce the noise level of the fan-shroud combination.
[0012] Another patent document DE112014004563T5 (referred herein as ‘563) discloses a double bell mouth shroud encircling a circular fan with a plurality of fan blades. The double bell mouth as disclosed in ‘563 further has an inlet to receive air and an outlet to outlet air. Here, the outlet radius is about 10% of the inlet radius to increase air flow rate and reduce noise level.
[0013] The US patent document US9267419B2 (referred herein as ‘419) discloses a convex fan shroud assembly that includes a front frame defining an air intake opening. The convex fan shroud as disclosed in ‘419 includes a convex top wall, a convex bottom wall and a pair of opposed convex side walls connected to the frame. The convex walls define a barrel shaped shroud body to accommodate the fan. Thus, the convex fan shroud has an optimized shape leading to high air flow rates through the radiator.
[0014] Though many fan shroud assemblies are available with increased air flow rate, there is always room for improvement related to the cooling arrangements for internal combustion engines.

[0015] Summary of the invention
[0016] The present invention overcomes the drawbacks of the prior art by providing a fan shroud with bell mouth radius at the jet ring junction to increase mass air flow rate through the radiator. The fan shroud assembly of the present invention comprises a frame assembly to provide structural support for attachment of the fan assembly to a vehicle structure such as a radiator. The frame assembly has a front opening for air inlet and a back opening to receive the fan assembly. The frame assembly focusses the airflow from the radiator to the fan assembly for cooling purposes.
[0017] In accordance to one embodiment of the present invention, a protruded bell mouth is formed around the corner edges of the frame assembly to increase the corner gap between the radiator plane and the frame front opening to increase mass air flow rate through the radiator.
[0018] Thus, the corner gap between the radiator plane and the frame front opening is maximized by forming a bell mouth radius at a jet ring junction to improve mass air flow rate through the radiator.
[0019] Brief description of the drawings:
[0020] The foregoing and other features of embodiments will become more apparent from the following detailed description of embodiments when read in conjunction with the accompanying drawings. In the drawings, like reference numerals refer to like elements.
[0021] FIG 1 illustrates a fan shroud assembly, in accordance to one or more embodiment of the invention.
[0022] FIG 2a illustrates air flow through the geometry of a conventional fan shroud assembly, in accordance to one or more embodiment of the present invention.
[0023] FIG 2b illustrates a detailed view of air flow through the fan shroud assembly, in accordance to one or more embodiment of the present invention.
[0024] FIG 3 is a graph illustrating air flow in current fan shroud assembly against conventional fan shroud assembly.
[0025] Detailed description of the invention:
[0026] Reference will now be made in detail to the description of the present subject matter, one or more examples of which are shown in figures. Each example is provided to explain the subject matter and not a limitation. Various changes and modifications obvious to one skilled in the art to which the invention pertains are deemed to be within the spirit, scope and contemplation of the invention.
[0027] The figures depict a simplified structure only showing some elements and functional entities, all being logical units whose implementation may differ from what is shown. The connections shown are logical connections; the actual physical connections may be different.
[0028] While the present invention has been described with respect to certain embodiments, it will be apparent to those skilled in the art that various changes and modification may be made without departing from the scope of the invention as defined in the following claims.
[0029] The present invention relates to a fan shroud assembly with bell mouth radius at the jet ring junction to increase mass air flow rate through the radiator. The fan shroud assembly of the present invention comprises a frame assembly to provide structural support for attachment of the fan assembly to a vehicle structure. The frame assembly has a front opening for air inlet and a back opening to receive the fan assembly. The frame assembly focusses the airflow from the radiator core to the fan assembly for cooling purposes.
[0030] Here, the corner gap between the radiator plane and the frame front opening is maximized by forming a bell mouth radius at a jet ring junction for improving mass air flow rate through the radiator.
[0031] FIG 1 illustrates a fan shroud assembly, in accordance to one or more embodiment of the invention. The fan shroud assembly (100) comprises a frame assembly (101) to provide structural support for attachment of the fan assembly (103) to a vehicle structure such as a radiator (102). The frame assembly (101) has a front opening for air inlet and a back opening to receive the fan assembly (103). Here, the fan assembly (103) further comprises a plurality of blades and a fan drive shaft. The frame assembly (101) focusses the airflow from the radiator (102) to the fan assembly (103) for cooling purposes. Here, the corner gap between the radiator plane (102) and the frame front opening is maximized by forming a bell mouth radius at a jet ring junction for improving mass air flow rate through the radiator (102).
[0032] In accordance to one embodiment of the present invention, a protruded bell mouth is formed around the corner edge (101a) of the frame assembly (101) to increase the corner gap between the radiator plane and the frame front opening to increase mass air flow rate through the radiator (102).
[0033] Further, the effect of the fan shroud assembly (100) on overall airflow driven by a fan has been studied and the optimized shape of the fan shroud has been developed using 3D computational fluid dynamics (CFD).
[0034] FIG 2a illustrates the air flow through the corner edges of the conventional fan shroud assemblies. As shown in FIG 2a, the distance between the radiator plane (201) and the frame front face (202) is small resulting in high air pressure built up in that region in conventional fan shroud assemblies (202). Thus, the build-up high pressure results in low air flow towards the air inlet region of the conventional fan shroud assembly (202).
[0035] FIG 2b illustrates a detailed view of air flow through the fan shroud assembly, in accordance to one or more embodiment of the present invention
[0036] As shown in FIG 2b, the fan shroud assembly (200) with a protruded bell mouth around the corner edges (101a) of the frame assembly (101) increases the corner gap between the frame front opening (101) and the radiator plane (102) leading to an improved mass air flow rate through the radiator (102) when compared to the conventional fan shroud assemblies (200, as shown in FIG 2a).
[0037] Further as shown in FIG 2b, the optimized guide curve (104) between the frame assembly (101) front opening and the radiator (102) plane provides funneling effect thereby resulting in low air pressure towards the frame air inlet region, leading to better exit characteristics.
[0038] In accordance to one embodiment of the present invention, the optimized guide curve (104) formed at the corner edges (101a) of the shroud frame assembly (101) is a Bezier Curve.
[0039] FIG 3 is a graph illustrating mass air flow rate in current fan shroud assembly against conventional fan shroud assembly.
[0040] As shown in FIG 3, providing a protruded bell mouth around the corner edges (101a) of the frame assembly (101) decreases the resistance to air flow through the radiator (102).
[0041] Thus, the fan shroud assembly (100) of the present invention provides increased air flow rate by providing a protruded bell mouth around the corner edges (101a) of the frame assembly (101) so that the corner gap between the frame front opening (101) and the radiator plane (102) increases leading to an improved mass air flow rate through the radiator (102) when compared to the conventional fan shroud assemblies.
[0042] Thus, the fan shroud assembly (100) of the present invention may be implemented in any system that utilizes liquid to air heat exchanger or radiator in combination with a fan assembly for cooling purpose.
[0043] While the present invention has been described with respect to certain embodiments, it will be apparent to those skilled in the art that various changes and modification may be made without departing from the scope of the invention as defined in the following claims.