A HEAT EXCHANGER

A heat exchanger having multiple segments is described. The heat exchanger includes a pair of manifolds, having tubes extending therein. Further, a first blocking element is provided in a manifold to divide the tubes into a first set of tubes and a second set of tubes having a fluid communication with each other. Further, a second blocking element is provided in the manifold, corresponding to the second set of tubes, to further divide the second set of tubes into a first segment of tubes and a second segment of tubes. Further, an inlet is provided on the manifold to introduce the heat exchange fluid to the first set of tubes. Further, a plurality of outlets provided on the manifold to receive the heat exchange fluid from the second set of tubes.

The present invention generally relates to heat exchangers, and in particularly, the heat exchangers having multiple segments to enable uniform distribution of heat exchange fluid in the heat exchangers.

Generally, HVAC systems are implemented in vehicles to provide comfort driving to the driver and occupants. The HVAC system generally includes heat exchangers (i.e., evaporators, condensers), an expansion valve and a compressor. The heat exchangers are connected to the expansion valve and the compressor through conduits for circulation of refrigerant. Typically, the heat exchangers are provided with heat tubes/plates extending between two manifolds, and a baffle/blocking member is provided in a manifold to divide the heat tubes into a first portion of tubes and a second portion of heat tubes in a fluid communication with each other. Each portion of heat tubes may include an opening for introducing/receiving the refrigerant into the heat tubes based on the type of mode.

The refrigerant flows through the tubes in the first portion of tubes and the second portion of tubes to absorb heat from the first portion of tubes and second portion of tubes respectively. As the refrigerant absorbs heat from the first portion of tubes, the density of the refrigerant is reduced. Then, the refrigerant enters into the second portion of tubes and is non-uniformly distributed in the second portion of tubes due to lower density of the refrigerant. Generally, when the density of refrigerant reduces, the refrigerant will follow a path of low resistance and exit the heat exchanger. As the refrigerant is non-uniformly distributed in the second portion of tubes, heat exchange between the refrigerant in the second portion of tubes and air is not uniform, which affects efficiency of the heat exchanger. Due to non-uniform distribution of refrigerant in the second portion of tubes, so called dead zones are created where the heat exchange is sub-optimal.

InFIG. 1, a thermal image of the conventional heat exchanger100is presented. In the conventional heat exchanger100, an outlet is provided in a top section of the second portion of tubes104, so when the refrigerant enters into the second portion of tubes104, the refrigerant is unevenly distributed in the second portion of tubes104which causes formation of the dead zones102in the lower section of the second portion of tubes104. If the outlet is repositioned to a lower section of the second portion of tubes104, the dead zones102are formed in the top section of the second portion of tubes104. To overcome such shortcomings, two outlets are provided in the second portion of manifold cooperating with the second portion of tubes. However, such design again leads to fast egress of the refrigerant from the second portion of tubes without getting distributed to whole area of the second portion of tubes since the refrigerant follows less resistant path to egress from the heat exchanger. Hence, the heat exchange rate is not optimal.

Accordingly, there is a need for a heat exchanger allowing uniform distribution of refrigerant throughout the heat exchange elements present in the heat exchanger to enhance the efficiency of the heat exchanger.

Another object of the present invention is to reduce dead zones created in the heat exchange elements of the heat exchanger that affect efficiency of the heat exchanger.

In the present description, some elements or parameters may be indexed, such as a first element and a second element. In this case, unless stated otherwise, this indexation is only meant to differentiate and name elements which are similar but not identical. No idea of priority should be inferred from such indexation, as these terms may be switched without betraying the invention. Additionally, this indexation does not imply any order in mounting or use of the elements of the invention.

In view of the foregoing, an embodiment of the invention herein provides a heat exchanger having multiple segments to provide optimum heat exchange rate. The heat exchanger includes a first manifold, a second manifold provided opposite to the first manifold, a plurality of tubes, a first blocking element, a second blocking element, an inlet and a plurality of outlets. The plurality of tubes is extended between the first manifold and the second manifold to enable flow of heat exchange fluid in the plurality of tubes. The first blocking element is provided in the first manifold to divide the plurality of tubes into a first set of tubes and a second set of tubes. The second set of tubes is in a fluid communication with the first set of tubes through the second manifold. The inlet is provided on the first manifold, corresponding to the first set of tubes, to introduce the heat exchange fluid to the first set of tubes. The second blocking element is provided in the first manifold, corresponding to the second set of tubes, to further divide the second set of tubes into a first segment of tubes and a second segment of tubes. Further, direction of flow of the heat exchange fluid is same in both the first segment of tubes and the second segment of tubes. The plurality of outlets is provided on the first manifold, corresponding to the second set of tubes, to receive the heat exchange fluid from the second set of tubes.

In one embodiment, the plurality of outlets comprises a first outlet and a second outlet. The first outlet may be provided on the first manifold, corresponding to the first segment of tubes, to egress the heat exchange fluid from the first segment of tubes. The second outlet may be provided on the first manifold, corresponding to the second segment of tubes, to receive the heat exchange fluid from the second segment of tubes.

In another embodiment, the heat exchanger further includes a first perforated blocking element that is adapted to cooperate with at least few of the second set of tubes in the first manifold, to increase pressure drop of the heat exchange fluid at the exit of the second set of tubes.

In another embodiment, the first perforated blocking element provided in the first manifold is adapted to partially block the passage of the second outlet to facilitate uniform distribution of the heat exchange fluid in the second set of tubes.

In yet another embodiment, the heat exchanger further includes a second perforated blocking element and a third perforated blocking element. The second perforated blocking element and the third perforated blocking element are provided in the second manifold and the first manifold respectively, corresponding to the second segment of tubes, to limit flow of the heat exchange fluid into the second segment of tubes that enables uniform distribution of the heat exchange fluid in the second set of tubes.

In accordance to an embodiment, the heat exchanger further includes a fourth perforated blocking element that is provided in the first manifold, corresponding to the first set of tubes, to enable uniform distribution of the heat exchange fluid in the first set of tubes.

In one embodiment, number of tubes in the second set of tubes is higher than the number of tubes in the first set of tubes, and the number of tubes in the first segment of tubes is higher than the number of tubes in the second segment of tubes.

In accordance with another embodiment, the heat exchanger includes a jumper line that is adapted to connect the first outlet and the second outlet to merge the first outlet and the second outlet fluidically and allow formation an outlet block.

In another embodiment, the first perforated blocking element, the second perforated blocking element, the third perforated blocking element, and the fourth perforated blocking elements are baffles having at least one of holes, vents and combination thereof.

It must be noted that the figures disclose the invention in a detailed enough way to be implemented, the figures helping to better define the invention if needs be. The invention should however not be limited to the embodiment disclosed in the description.

The present invention relates to a heat exchanger having multiple segments to enable uniform distribution of heat exchange fluid in heat exchange elements. According to the aspect, the heat exchanger includes a pair of manifolds and heat exchange elements extending between the pair of manifolds. A pair of blocking elements is introduced into a manifold to divide the heat exchange elements into multiple sets of tubes. The heat exchange fluid may circulate from a first set of tubes to a second set of tubes amongst the multiple sets of tubes. Further, a baffle is provided in the second set of tubes to increase pressure drop of the heat exchange fluid in the second set of tubes. As the baffle is provided to increase the pressure drop of the heat exchange fluid, the heat exchange fluid distribution is improved in the second set of tubes.

While aspects relating to a blocking element provided in a heat exchanger to form a first set of tubes and a second set of tubes as described above and henceforth can be implemented in any number of baffles provided in the heat exchanger to form multiple sets of tubes, the embodiments are described in the context of the following system(s).

FIG. 2illustrates a schematic view of a multi-segment heat exchanger200, in accordance with an embodiment of the present subject matter. The multi-segment heat exchanger200will be referred to as a heat exchanger200hereafter. The heat exchanger200includes a first manifold202, a second manifold204, and a plurality of heat exchange elements206extending between the first manifold202and the second manifold204. In one embodiment, the first manifold202and the second manifold204include slots to receive the plurality of heat exchange elements206and distribute heat exchange fluid to the plurality of heat exchange elements206. In one example, the plurality of heat exchange elements206may be tubes or plates. Hereinafter, the plurality of heat exchange elements206will be referred to as a plurality of tubes206. Further, blocking elements are provided in the first manifold202to divide the plurality of tubes206into multiple segments of tubes. For instance, the blocking elements comprise a first blocking element208, and a second blocking element210. The first blocking element208is provided in the first manifold202to divide the plurality of tubes206into a first set of tubes212and a second set of tubes214. The first set of tubes212is in a fluid communication with the second set of tubes214through the second manifold204. In other words, as the first blocking element208is provided in the first manifold202, the second set of tubes214receives the heat exchange fluid from the first set of tubes212through the second manifold204. The heat exchange fluid, hereinafter referred to as refrigerant, is adapted to flow from the first manifold202to the second manifold204through the first set of tubes212. Further, the refrigerant is adapted to flow from the second manifold204to the first manifold202in the second set of tubes214.

The second blocking element210is provided in the first manifold202corresponding to the second set of tubes214. In other words, the second blocking element210provided in the first manifold202in such a way that the second blocking element210lies in a portion of the first manifold202where the second set of tubes214are received. Further, the second blocking element210is adapted to divide the second set of tubes214into a first segment of tubes216and a second segment of tubes218. The refrigerant flows in the same direction in both the first segment of tubes216and the second segment of tubes218. In other words, the refrigerant flows from the second manifold204to the first manifold202in both the first segment of tubes216and the second segment of tubes218. Further, an inlet220is provided on the first manifold202corresponding to the first set of tubes212to introduce the refrigerant to the first set of tubes212. In other words, the inlet220is coupled to the first manifold202in such a way that the inlet220provides the refrigerant exclusively to the first set of tubes212.

Further, a plurality of outlets is coupled to the first manifold202corresponding to the second set of tubes214. In other words, the plurality of outlets is provided on the first manifold202in such a way that the plurality of outlets receives the refrigerant from the second set of tubes214. In one embodiment, the plurality of outlets includes a first outlet222, and a second outlet224. The first outlet222is provided on the first manifold202, corresponding to the first segment of tubes216, to receive the refrigerant from the first segment of tubes216. Further, the second outlet224is provided on the first manifold202, corresponding to the second segment of tubes218, to receive the refrigerant from the second segment of tubes218.

The heat exchanger200may further comprise a first perforated blocking element226cooperatively coupled to at least few of the second set of tubes214in the first manifold202to increase pressure drop of the refrigerant at the exit of the second set of tubes214. In one embodiment, the first perforated blocking element226provided in the first manifold202is adapted to partially block the passage of the second outlet224to facilitate uniform distribution of the refrigerant in the second set of tubes214. In other words, the first perforated blocking element226is provided in the first manifold202in such a way that the first perforated blocking element226blocks the refrigerant flowing to the second outlet224. Further, the first perforated blocking element226is adapted to limit the refrigerant flow in the second segment of tubes218which enables uniform distribution of the refrigerant throughout the second set of tubes214. In heat pump mode, when the refrigerant enters into the first set of tubes212from the inlet220, the refrigerant absorbs heat from the air present around the first set of tubes212and the density of the refrigerant is reduced due to heat exchange between the refrigerant and the air. Thereafter, density varied refrigerant enters into the second set of tubes214and absorbs heat from the air present around the second set of tubes214. As the density of refrigerant entering into the second set of tubes214is lesser as compared to the density of refrigerant entering into the first set of tubes212, the refrigerant may inadequately absorb heat and then exit through the plurality of outlets. To alleviate such effect, the first perforated blocking element226is provided in the first manifold202which partially blocks the refrigerant flowing through the second outlet224. The first perforated blocking element226may partially block flow of the refrigerant and consequently improve distribution of the refrigerant in the second set of tubes214.

In one embodiment, number of tubes in the second set of tubes214is higher than the number of tubes in the first set of tubes212. In another embodiment, the number of tubes in the first segment of tubes216is higher than the number of tubes in the second segment of tubes218. Further, the heat exchanger200may further include a jumper line228adapted to connect the first outlet222and the second outlet224to merge them fluidically and enable formation of an outlet block230. For example, the refrigerant received at the first outlet222is transferred to the outlet block230where the refrigerant from the second outlet224also received.

FIG. 3illustrates a schematic view of the heat exchanger100having a second perforated blocking element302in the second manifold204. In heat pump mode, flow of the refrigerant in the second segment of tubes218is high as compared to the refrigerant flow in the first segment of tubes216which leads to an inefficient heat exchange in the first segment of tubes216. To alleviate such effect, the second perforated blocking element302is provided in the second manifold204as shown inFIG. 3. The second perforated blocking element302is coupled to the second manifold204corresponding to the second set of tubes214. In one embodiment, the second perforated blocking element302is placed in the second manifold204in such a way that the second perforated blocking element302is parallel to the second blocking element210. The second perforated blocking element302is adapted to limit the flow of refrigerant into the second segment of tubes218, which results in uniform distribution of the refrigerant throughout the second set of tubes214.

FIG. 4illustrates a schematic view of the heat exchanger200having multiple subsections in the second set of tubes214, in accordance with an embodiment of the present subject matter. The heat exchanger200further includes a third perforated blocking element402provided in the first manifold202posterior to the second blocking element210, to divide the second set of tubes214into multiple segments of tubes. In one embodiment, the second perforated blocking element302and the third perforated blocking element402are a baffle having adjusting openings cross section to control flow of refrigerant therein. Further, a fourth perforated blocking element404is provided in the first manifold202anterior to the first blocking element208to divide the first set of tubes212into two segments to enable uniform distribution of refrigerant in the first set of tubes212. In other words, the fourth perforated blocking element404is provided in the first manifold202corresponding to the first set of tubes212to avoid formation of dead zones in the first set of tubes212. Further, the refrigerant may be, but not limited to, R11, R12, R113, R114, R115, R22, R123, R134a, R404a, R407C, and R410a.

FIG. 5illustrates various designs of the perforated blocking elements. In one embodiment, the first perforated blocking element226, the second perforated blocking element228, the third perforated blocking element302, and the fourth perforated blocking elements402are baffles. In another embodiment, the baffles may include at least one of holes, vents and combination thereof as shown in theFIG. 5. As the refrigerant uniformly distributed throughout the plurality of tubes206, thermal performance of the heat exchanger is increased.

In any case, the invention cannot and should not be limited to the embodiments specifically described in this document, as other embodiments might exist. The invention shall spread to any equivalent means and any technically operating combination of means.