FORM 2
The Patent Act 1970
(39 of 1970)
AND
The Patent Rules, 2003
COMPLETE SPECIFICATION (SEE SECTION 10 AND RULE 13)
TITLE OF THE INVENTION Dual receiver drier integrated condenser
APPLICANT
TATA MOTORS LIMITED
an Indian company having its registered office
at Bombay house, 24 Homi Mody Street,
Hutatma Chowk, Mumbai 400 001,
Maharashtra, India.
The following specification particularly describes the invention and the manner in which it is to be performed.

FIELD OF THE INVENTION
[0001] The present disclosure relates to Dual receiver drier integrated condenser. More particularly relates a dual receiver drier diversion based condenser for enhancing heat rejection from the refrigerant and maximizing the effectiveness of the condenser.
BACKGROUND OF THE INVENTION
[0002] A Receiver Drier (RD) is provided in a condenser of an air conditioner for a motor vehicle to store and desiccate refrigerant. Generally, a condenser receives a fluid such as the refrigerant in a vapor phase, at a reasonably high temperature, and cools the refrigerant by transforming a vapor phase to a liquid phase.
[0003] FIG. 1 illustrates a conventional condenser 100 with a single integral receiver drier, according to the prior art. The condenser 100 includes a pair of generally vertical, parallel manifolds, first or inlet header 102 and second or outlet header 104 spaced apart a predetermined distance. The condenser 100 also includes a plurality of generally parallel, tubes 106 extending between the headers 102 and 104 and conducting fluid such as a refrigerant between them. The condenser 100 includes a fluid inlet 108 for directing the fluid into the condenser 100 formed in the inlet header 102 and a fluid outlet for directing the fluid out of the condenser 100 formed in the outlet header 104. The condenser 100 also includes a plurality of convoluted or louvered fins disposed between the tubes 106 and attached to an exterior of each of the tubes 106. The fins serve as a means for conducting heat away from the tubes 106 while providing additional surface area for convective heat transfer by air flowing over the condenser 100. The condenser 100 includes an integral receiver drier 112, disposed in and integral with the outlet header 104.

[0004] As the refrigerant flows in a back and forth pattern through the condenser, heat is transferred from the vapor phase of the refrigerant to condense to the liquid phase. The liquid phase continues to flow through a pass structure of the condenser connected to the tubes that directs the refrigerant through a plurality of flow paths until the fluid reaches an outlet from where it is carried to other components of air conditioning system. The pass structures of the conventional condensers allows the refrigerant flow in a single direction. No separation of condensed refrigerant and non-condensed refrigerant is considered by the existing condenser. Also same internal tube structure is used across complete condenser core. Further, Same fin geometry is formed across the condenser resulting in non-uniform airflow distribution which hampers complete utilization of the condenser.
[0005] Thus, it is desired to address the above mentioned disadvantages or other shortcomings or at least provide a useful alternative.
OBJECT OF THE INVENTION
[0006] The principal object of the present invention is to provide a dual Receiver Drier (RD) integrated condenser. A Dual receiver drier in a condenser is provided to desiccate a refrigerant and maximizing the condensing efficiency.
[0007] Another object of the present invention is to integrate dual Receiver Drier (RD) each of the RD integral with a housing at either side of the condenser, wherein the dual RD is a provision to separate the liquid refrigerant from mixture of liquid & vapour refrigerant flowing through the condenser tubes. The dual RD facilitates separation of liquid refrigerant immediately at the end of a pass.
[0008] Yet another object of the present invention is to provide varying fin geometry facilitating uniform air-flow across the condenser core for condenser’s complete utilization.

[0009] Yet another object of the present invention is to provide a variable internal cross-section of tubes in which a size is finalized depending on an estimated state of refrigerant passing through that particular tube.
[0010] Yet another object of the present invention is provide a unique pass structure path based on diversion wherein the heavier refrigerant flows to lower pass and lighter refrigerant flows to higher pass.
SUMMARY OF THE INVENTION
[0011] In accomplishing the objects of the invention, there has been provided, according to one aspect of the invention, a condenser for an air-conditioning system. The condenser comprises a first header tank, a second header tank, a plurality of tubes arranged between the first header tank and the second header tank, and a dual Receiver Drier (RD) each of the RD integral with a housing at either side of the condenser. The dual RD facilitates separation of liquid refrigerant at the end of a pass.
[0012] In an embodiment, a first RD of the dual RD integral with the housing of the first header tank, wherein the first RD has an inlet at the first header tank from at least two passes of the condenser.
[0013] In an embodiment, the inlet at the first header tank for conducting the flow of the refrigerant into the condenser is provided at a center of the condenser.
[0014] In an embodiment, a second RD of the dual RD integral with the housing on the second header tank, wherein the second RD has an inlet from at least one pass of the condenser such that the condensed refrigerant exits from the second RD to the second header and then through the last pass of the condenser.

[0015] In an embodiment, a variable fin geometry is provided across the condenser for facilitating a uniform air-flow across the condenser.
[0016] The condenser of claim 5, wherein the variable fin geometry is determined based on at least one of a fin pitch, a louver height, a fin height, a louver depth, a louver angel, and a louver pitch.
[0017] In an embodiment, an internal structure of the tubes are different for each of the pass to address varying dryness fraction of the refrigerant.
[0018] In an embodiment, a cross-sectional area of the tubes of the each of the passes of the condenser is determined based on an estimated phase or state of the refrigerant passing through that particular tube.
[0019] In an embodiment, a pressure at a lower side of the refrigerant and an air side of the refrigerant drops across the condenser.
[0020] In an embodiment, the dual RD cooperates with the first header tank and the header tank to ensure that only the non-condensed refrigerant flows through the tubes of the condenser while the condensed refrigerant flows to one of the RD.
[0021] These and other aspects 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 preferred 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 FIGURE
[0022] This method and system is 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:
[0023] FIG. 1 illustrates a conventional condenser with a single integral receiver drier, according to the prior art;
[0024] FIG. 2 illustrates a proposed condenser with a dual integral receiver drier, according to an embodiment as disclosed herein;
[0025] FIG. 3 illustrates various parameters to be varied for variable fin geometry, according to an embodiment as disclosed herein; and
[0026] FIG. 4 illustrates tubes with different internal structures, according to an embodiment as disclosed herein.
DETAILED DESCRIPTION OF THE INVENTION
[0027] 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. Also, the various embodiments described herein are not necessarily mutually exclusive, as some embodiments can be combined with one or more other embodiments to form new embodiments. The term “or” as used herein, refers to a non-exclusive or, unless otherwise indicated. The examples used herein are intended merely to facilitate an understanding of ways in which

the embodiments herein can be practiced and to further enable those skilled in the art to practice the embodiments herein. Accordingly, the examples should not be construed as limiting the scope of the embodiments herein.
[0028] Embodiments herein discloses a condenser for an air-conditioning system. The condenser comprises a first header tank, a second header tank, a plurality of tubes arranged between the first header tank and the second header tank, and a dual Receiver Drier (RD) each of the RD integral with a housing at either side of the condenser, wherein the dual RD facilitates separation of liquid refrigerant immediately at the end of a pass.
[0029] Unlike the conventional systems, the proposed invention discloses an improved condenser design that facilitates effective use of a condenser core area facilitated by providing maximum area for phase change and to reduce the refrigerant side pressure drop facilitated by a dual RD and diversion based pass structure. In a conventional condenser, a path of air-flow is concentrated at a certain area of the condenser core creating some underutilized and some unutilized parts of the core. To counter this, a variable fin geometry is provided across the condenser core facilitating a uniform air-flow across the core and complete utilization of the core. The Dual RD ensures a separation of liquid refrigerant from mixture of liquid and vapor refrigerant, at the earliest. A different tube structure for each pass is also proposed as the refrigerant is in two phases and due to presence of two phases, a capacity to reject heat also varies. Tube cross-sectional area of the pass is decided according to the estimated phase of the refrigerant. An entry of the refrigerant is also provided through the center of the condenser. Due to center entry, there is provision to separate the refrigerant such that the heavier refrigerant flows through the lower pass and lighter refrigerant flows through the higher pass.
[0030] The accompanying drawings are used to help easily understand various technical features and it should be understood that the embodiments

presented herein are not limited by the accompanying drawings. As such, the present disclosure should be construed to extend to any alterations, equivalents and substitutes in addition to those which are particularly set out in the accompanying drawings. Although the terms first, second, etc. may be used herein to describe various elements, these elements should not be limited by these terms. These terms are generally only used to distinguish one element from another.
[0031] Referring now to the drawings, and more particularly to FIGS. 2 through 4, there are shown preferred embodiments.
[0032] The FIG. 2 illustrates a proposed condenser 200 with a dual integral receiver drier (RD) (208a and 208b), according to an embodiment as disclosed herein. The condenser 200 includes a pair of generally vertical, parallel header tanks (202 and 204). The first header tank 202 and the second header tank 204 spaced apart at a predetermined distance. The condenser 200 also includes a plurality of generally parallel, tubes 206 extending between the first header tank 202 and the second header tank 204 and conducting fluid such as a refrigerant between them. The condenser 200 includes a fluid inlet for directing the fluid into the condenser 200 formed in the header tank 202 and a fluid outlet for directing the fluid out of the condenser 200 formed in the header tank 204. The tubes 206 extends form a pass structure such as pass 1, pass 2, pass 3, pass 4, and pass 5 to direct the refrigerant. In an example implementation, pass structure including five passes may deliver the required performance. However, the number of passes should not be construed as a limitation and increasing or decreasing the number of passes may be possible. In an embodiment, an internal structure of the tubes are different for each of the pass to address varying dryness fraction of the refrigerant. A different tube structure for each pass is also proposed as the refrigerant is in two phases and due to presence of two phases, a capacity to reject heat also varies. In an embodiment, a cross-sectional area of the tubes 206 of the each of the passes of the condenser 200 is determined based on estimated phase of the refrigerant of the condenser 200. The condenser 200 also includes the dual RD 208a and 208b each

of the RD integral with a housing at either side of the condenser, wherein the dual RD facilitates separation of liquid refrigerant from mixture of liquid & vapor refrigerant flowing through the condenser tubes.
[0033] In an embodiment, a first RD 208a of the dual RD integral with the housing of the first header tank 202. The first RD has the inlet at the first header tank 202 from at least two passes of the condenser 200 such that the refrigerant from 1 of the passes, separates such that the non-condensed refrigerant flows to the next pass of the condenser and the condensed refrigerant flows to the first RD 208a For example, the complete refrigerant flows through the pass 2 to the first RD 208a. Vapour part of the refrigerant flows from the pass 3 to the pass 4 and liquid part of the refrigerant flows to the first RD 208a.
[0034] In an embodiment, the inlet at the first header tank 202 for conducting the flow of the refrigerant into the condenser 200 is provided at a center of the condenser 200 such that at the end of first pass, refrigerant entering the second header separates such that the non-condensed refrigerant with a lower dryness fraction flows through the lower pass of the condenser and the non-condensed refrigerant with a higher dryness fraction flows through the upper pass of the condenser. Due to center entry, there is provision to separate the refrigerant such that the heavier refrigerant flows through the lower pass and lighter refrigerant flows through the higher pass.
[0035] In an embodiment, a second RD of the dual RD integral with the housing on the second header tank, wherein the second RD has an inlet from at least one pass of the condenser such that the condensed refrigerant exits from the second RD to the second header and then through the last pass of the condenser.

from the tubes 206 while providing additional surface area for convective heat transfer by air flowing over the condenser 200.
[0037] Unlike convention system, the proposed dual RD facilitates separation of liquid refrigerant immediately at the end of the pass (such as pass 3 or pass 5). Due to the mentioned condenser construction, air side as well as refrigerant side pressure drop across the condenser is reduced. The dual RD cooperates with the first header tank 202 and the header tank 204 to ensure that only the non-condensed refrigerant flows through the tubes 206 of the condenser 200 while the condensed refrigerant flows to the first RD 208a.
[0038] The FIG. 3 illustrates various parameters to be varied for variable fin geometry, according to an embodiment as disclosed herein. In an embodiment, a variable fin geometry is provided across the condenser for facilitating a uniform air-flow across the condenser 200. The variable fin geometry is determined based on at least one of a fin pitch, a louver height, a fin height, a louver depth, a louver angel, and a louver pitch. Unlike the conventional condensers, the varying fin geometry facilitating uniform air-flow across the condenser core thus facilitating condenser’s complete utilization.
[0039] The FIG. 4 illustrates the tubes 206 with different internal structures, according to an embodiment as disclosed herein. Proposed different tube structure for each of the pass is possible to be implemented, as the refrigerant is in two phases and due to presence of two phases, a capacity to reject heat also varies.
[0040] 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 should be appreciated that the condenser 200 could be used as a heat exchanger in other applications besides motor vehicles or air conditions system. Also 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.

We Claim:
1. A condenser comprises:
a first header tank;
a second header tank;
a plurality of tubes arranged between the first header tank and the second header tank; and
a dual Receiver Drier (RD) each of the RD integral with a housing at either side of the condenser, wherein the dual RD facilitates separation of liquid refrigerant at the end of a pass.
2. The condenser of claim 1, wherein a first RD of the dual RD integral with the housing of the first header tank, wherein the first RD has an inlet at the first header tank from at least two passes of the condenser.
3. The condenser of claim 2, wherein the inlet at the first header tank for conducting the flow of the refrigerant into the condenser is provided at a center of the condenser.
4. The condenser of claim 1, wherein a second RD of the dual RD integral with the housing on the second header tank, wherein the second RD has an inlet from at least one pass of the condenser such that the condensed refrigerant exits from the second RD to the second header and then through the last pass of the condenser.
5. The condenser of claim 1, wherein a variable fin geometry is provided across the condenser for facilitating a uniform air-flow across the condenser.
6. The condenser of claim 5, wherein the variable fin geometry is determined based on at least one of a fin pitch, a louver height, a fin height, a louver depth, a louver angel, and a louver pitch.

7. The condenser of claim 1, wherein an internal structure of the tubes are different for each of the pass to address varying dryness fraction of the refrigerant.
8. The condenser of claim 1, wherein a cross-sectional area of the tubes of the each of the passes of the condenser is determined based on an estimated phase or state of the refrigerant passing through that particular tube.
9. The condenser of claim 1, wherein a pressure at a lower side of the refrigerant and an air side of the refrigerant drops across the condenser.
10. The condenser of claim 1, wherein the dual RD cooperates with the first header tank and the header tank to ensure that only the non-condensed refrigerant flows through the tubes of the condenser while the condensed refrigerant flows to one of the RD.