Patent Description:
These heat exchangers may be used in vehicles in order to cool inlet gases of a turbocharged internal combustion engine with a coolant liquid, for instance a water-based coolant liquid.

Such heat exchangers usually comprise a casing inside which there are channels dedicated to the circulation of the gases as well as passes for the coolant liquid to circulate inside the heat exchanger. The channels and the passes are arranged so that the gases and the coolant liquid can exchange calories, resulting in a drop of temperature for the gases.

More specifically, the channels can extend from one end of the heat exchanger bearing an air inlet to another end bearing an air outlet, the air circulating inside the heat exchanger from the air inlet to the air outlet. The channels are usually stacked horizontally, i.e. one next to the other in a direction perpendicular to that of the air flow. The liquid coolant can circulate in passes located in between the channels, from a liquid inlet to a liquid outlet. Due to this disposition of the liquid inlet and outlet relative to that of the passes, there can however be a risk of local boiling in the vicinity of the liquid outlet for the passes which are the farthest from the centre of the heat exchanger. These passes are indeed at risk of not being cooled enough by the coolant liquid. As such, there is a need for heat exchangers inside of which the coolant liquid flow is improved.

The present invention fits into this context by providing a heat exchanger with at least one corridor for the coolant liquid facing the passes located at a distance from the centre of the heat exchanger, thus improving the flow of the coolant liquid and avoiding local boiling in these passes.

In this context, the present invention is directed to a heat exchanger configured to cool an air flow with a coolant liquid, comprising a heat core, a first air flow duct located at a first longitudinal end of said heat core and a second air flow duct located at a second longitudinal end of said heat core, the heat core comprising a plurality of air flow channels defining liquid passes in between at least two air flow channels, said heat core comprising a plurality of plates enveloping the air flow channels and the liquid passes. According to the invention, at least one of the plates has at least a first projection defining a liquid chamber at the first longitudinal end of the heat core and at least a second projection defining a corridor connected to the liquid chamber and configured for the circulation of the coolant liquid, the corridor extending from the liquid chamber and in the direction of the second longitudinal end of the heat core.

The heat exchanger according to the invention requires a coolant liquid in order to cool the air. This air flows in the heat exchanger, and more precisely in its heat core, from the first air duct or air inlet located at its first longitudinal end, to the second air duct or air outlet located at its second longitudinal end which is opposed to the first longitudinal end.

The plurality of plates of the heat core, for instance four plates, define an internal housing for the air and the coolant liquid to circulate inside the heat core. More precisely, when circulating inside the heat core the air is contained in air flow channels whereas the coolant liquid can circulate in the spaces between these air flow channels, which form liquid passes. Two of the plates are used to delimitate the liquid passes vertically, by closing a volume inside of which the coolant liquid can circulate. One of these two plates bears the first projection defining the liquid chamber and the second projection defining the corridor, wherein the coolant liquid can circulate as well. In other words, the liquid chamber and the corridor are in liquid communication with the liquid passes. The projections of the plate making up the liquid chamber and the corridor extend opposite of the internal housing.

The liquid may be a water-based coolant liquid, e.g., a mix of water and glycol, which is designed to exchange calories with the air flowing inside the air flow channels. Each air flow channel is furthermore equipped with an air flow disrupter, which helps distribute the air within the heat core.

The presence of the corridor and its disposition help improve the distribution of the coolant liquid within the heat core.

In some embodiments, the corridor faces at least one of the liquid passes.

As an option of the invention, the corridor defined by the second projection is a first corridor, the plate having the first and second projections also having a at least third projection defining a at least second corridor connected to the liquid chamber and configured for the circulation of the coolant liquid.

There are thus at least two corridors extending from the liquid chamber and in the direction of the second longitudinal end of the heat core.

According to an optional characteristic of the invention, each of the at least two corridors faces one of the liquid passes.

According to an optional characteristic of the invention, the heat core comprises a group of central liquid passes and two lateral liquid passes bordering said group of central liquid passes, the first corridor facing one of the lateral liquid passes and the second corridor facing the other lateral liquid pass.

Each of the first corridor and second corridor extends alongside a transverse end of the plate having the liquid chamber. Such arrangement helps improve the coolant liquid flow in the lateral liquid passes, thus preventing local boiling in these lateral liquid passes.

According to another optional characteristic of the invention, the first corridor and the second corridor are parallel.

As such, they extend along straight lines which are also parallel to the air flow channels.

In some embodiments, the first corridor and the second corridor have the same dimension measured in a direction perpendicular to a longitudinal direction of the heat core.

This dimension corresponds to the width of the first corridor and the second corridor. The corridors having the same width helps ensure that the coolant liquid flows similarly on each side of the heat core.

According to an optional characteristic, the heat core comprises at least a coolant inlet and a coolant outlet, the first projection defining the liquid chamber bearing one of them.

The coolant liquid enters the heat core via the coolant inlet and exits it via the coolant outlet. Either the coolant inlet or the coolant outlet is located on the projection. In other words, either the coolant inlet is located on the liquid chamber or the coolant outlet is located on the liquid chamber.

In some embodiments, the liquid chamber defined by the first projection is a first liquid chamber, the plate having the first and second projections also having a fourth projection defining a second liquid chamber, such second liquid chamber being located at the second longitudinal end of the heat core, at least one of the corridors joining the first liquid chamber and the second liquid chamber.

There is then a first liquid chamber located at the first longitudinal end of the heat core and a second liquid chamber located at the second longitudinal end of the heat core, these first and second chambers being joined by the corridors.

According to another optional characteristic, the second liquid chamber is blind.

This means that the walls of the second liquid chamber do not have a hole in them, and more specifically that the second liquid chamber does not bear an inlet or an outlet.

According to another optional characteristic of the invention, the coolant inlet and the coolant outlet are located on opposite plates of the heat core.

Such arrangement of the coolant inlet and outlet ensures a satisfactory flow of coolant in the heat core, so that all the air flow channels are adequately cooled.

According to another optional characteristic of the invention, the coolant outlet is located closer to the first longitudinal end of the heat core whereas the coolant inlet is located closer to the second longitudinal end of the heat core.

Likewise, this arrangement of the coolant inlet and of the coolant outlet contributes to a satisfactory distribution of coolant liquid in the heat core.

Other characteristics, details and advantages of the invention will become clearer on reading the following description, on the one hand, and several examples of realisation given as an indication and without limitation with reference to the schematic drawings annexed, on the other hand, on which:.

The characteristics, variants and different modes of realisation of the invention may be associated with each other in various combinations, in so far as they are not incompatible or exclusive with each other. In particular, variants of the invention comprising only a selection of features subsequently described in from the other features described may be imagined, if this selection of features is enough to confer a technical advantage and/or to differentiate the invention from prior art.

Like numbers refer to like elements throughout drawings.

In the following description, the designations "longitudinal", "transversal" and "vertical" refer to the orientation of the heat exchanger according to the invention. A longitudinal direction corresponds to a direction in which the air flow channels of the heat exchanger mainly extend, this longitudinal direction being parallel to a longitudinal axis L of a coordinate system L, V, T shown in the figures. A transversal direction corresponds to a direction in which the liquid passes slot in between the air flow channels, this transversal direction being parallel to a transverse axis T of the coordinate system L, V, T, and perpendicular to the longitudinal axis L. Finally, a vertical direction corresponds to a vertical axis V of the coordinate system L, V, T, the vertical axis V being perpendicular to the longitudinal axis L and the transversal axis T.

<FIG> are perspective views of a heat exchanger <NUM> according to the invention, such heat exchanger <NUM> being destined to cool an air flow. The heat exchanger <NUM> can for example be installed in a vehicle such as an automobile vehicle in order to cool its inlet gases.

The heat exchanger <NUM> comprises a heat core <NUM>, which makes up its central portion. The heat core <NUM> is furthermore the part of the heat exchanger <NUM> where calorie exchanges occur, these calorie exchanges being essential to the cooling of the air flow. To this end, the heat core <NUM> comprises air flow channels <NUM> within which the air needing to be cooled can circulate. Such air flow channels are particularly visible on <FIG>, as well as on <FIG> which is a cross-section view. These air flow channels <NUM> extend from one side of the heat core <NUM> to the other according to a longitudinal direction, more particularly from a first longitudinal end <NUM> of the heat core to its second longitudinal end <NUM>. The air flow channels <NUM> are contained in an internal housing <NUM> of the heat core <NUM>, which is made of plates such as aluminium plates. As represented here, the heat core <NUM> comprises four rectangular plates, among which a first plate <NUM>, a second plate <NUM>, a third plate <NUM> and a fourth plate <NUM>. The first plate <NUM> and the third plate <NUM> face each other and extend mainly according to a longitudinal-transversal plane, whereas the second plate <NUM> and the fourth plate <NUM> face each other and extend mainly according to a longitudinal-vertical plane.

The air flow thus circulates in the internal housing <NUM> and more precisely in the air flow channels <NUM> from the second longitudinal end <NUM> to its first longitudinal end <NUM>. More specifically, the air flow may enter the heat exchanger <NUM> via an air inlet <NUM> located at the second longitudinal end <NUM> and may exit it via an air outlet <NUM> located at the first longitudinal end <NUM> of the heat core <NUM>. Both the air inlet <NUM> and the air outlet <NUM> are air flow ducts, and they may for instance be made of polyvinyl chloride.

Each air flow channel <NUM> is equipped with an air flow disrupter <NUM>, which helps distribute the air flow more homogeneously within the heat core <NUM>. These air flow disrupters are particularly visible on <FIG>. They snake inside their respective air flow channels <NUM> from one of their lateral ends in the vicinity of the first plate <NUM> to an opposite lateral end of the air flow channels <NUM> close to the third plate <NUM>, forming winglets in the air flow channels <NUM> so as to deviate the air flowing inside them.

The air flow channels <NUM> are stacked one next to the other according to a transverse direction, perpendicular to the longitudinal direction. The spaces between two contiguous air flow channels <NUM> define liquid passes <NUM>, within which a coolant liquid may circulate. This coolant liquid can be water-based; it can for instance be a mix of <NUM> % water and <NUM> % glycol. In addition to the liquid passes <NUM>, the coolant liquid may also circulate in the spaces between the air flow channels <NUM> and the first plate <NUM> on the one hand and between these air flow channels <NUM> and the third plate <NUM>. Among the liquid passes <NUM>, the heat core <NUM> comprises a group of central liquid passes <NUM> as well as two lateral liquid passes <NUM>, <NUM> bordering said group of central liquid passes <NUM>, among which a first lateral liquid pass <NUM> and a second lateral liquid pass <NUM>. The first lateral liquid pass <NUM> faces the second plate <NUM> whereas the second lateral liquid pass <NUM> faces the fourth plate <NUM>, although there may be an air flow channel <NUM> in between each of these first and second lateral liquid passes <NUM>, <NUM> and the plate <NUM>, <NUM> they respectively face. In any case, every air flow channel <NUM> and every liquid pass <NUM> is contained within the internal housing <NUM> of the heat core <NUM> of the heat exchanger <NUM>. In other words, this internal housing <NUM> participates in delimiting a volume for both the air flow and the coolant liquid to circulate inside of.

The heat exchanger <NUM> according to the invention is configured to receive the coolant liquid via a coolant inlet <NUM> and to evacuate the coolant liquid via a coolant outlet <NUM>. Similarly to the air inlet <NUM> and the air outlet <NUM>, the coolant inlet <NUM> and the coolant outlet <NUM> are ducts and can be made of polyvinyl chloride. As shown on <FIG>, the coolant inlet <NUM> and the coolant outlet <NUM> may be located on opposite plates of the heat core <NUM>, with here the coolant outlet <NUM> located on the first plate <NUM> and the coolant inlet <NUM> located on the third plate <NUM>. This ensures the coolant liquid can flow through the heat core <NUM> from the first plate <NUM> to the third plate <NUM>, which means from one of its lateral end to the other, and cool the air flowing in the air flow channels <NUM> adequately. To this end, the coolant outlet <NUM> may in addition be located in the vicinity of the first longitudinal end <NUM> of the heat core <NUM> while the coolant inlet <NUM> is closer to its second longitudinal end <NUM>, thus reinforcing the spreading of the coolant liquid within the heat core <NUM>.

The first, second, third and fourth plates <NUM>, <NUM>, <NUM>, <NUM> making up the heat core <NUM> are mostly plane. However, according to the invention at least one of these plates, here the first plate <NUM>, has a first projection in addition to its plane portion. Such first projection is located at the first longitudinal end <NUM> of the heat core <NUM> and it defines a liquid chamber <NUM> which is in liquid communication with the liquid passes <NUM>, so that the coolant liquid can circulate through it. This liquid chamber <NUM> is particularly visible on <FIG>. The height H of the first projection, which corresponds to its dimension measured according to the vertical direction, can for example be of the order of <NUM>,<NUM>, as shown on <FIG>. The liquid chamber is made of four sides <NUM>, <NUM>, <NUM>, <NUM> extending from the first plate <NUM> and opposite to the internal housing <NUM>. These four sides <NUM>, <NUM>, <NUM>, <NUM> are joined by a back wall <NUM>, which is pierced with a hole <NUM> to which either the coolant inlet <NUM> or the coolant outlet <NUM> can be connected. The back wall <NUM> is mainly parallel to the plane portion of the first plate <NUM>.

Out of these four sides, two delimit the liquid chamber <NUM> according to the transverse direction, namely a first lateral side <NUM> and a second lateral side <NUM>. These lateral sides <NUM>, <NUM> extend along the longitudinal direction, that is to say mainly parallel to the air flow channels <NUM> and to the liquid passes <NUM>. The liquid chamber <NUM> is furthermore delimited according to the longitudinal direction by two longitudinal sides, with a first longitudinal side <NUM> and a second longitudinal side <NUM>. These longitudinal sides <NUM>, <NUM> extend along the transverse direction, and as such are mainly perpendicular to the air flow channels <NUM> and the liquid passes <NUM>.

In addition to the first projection, the first plate <NUM> also has a second projection defining a corridor <NUM> which is connected to the liquid chamber <NUM> and is configured for the circulation of the coolant liquid. This corridor <NUM> extends from the liquid chamber <NUM> and in the direction of the second longitudinal end <NUM> of the heat core <NUM>. More precisely, the corridor <NUM> is an extension of either the first lateral side <NUM> or the second lateral side <NUM>.

In some embodiments and as illustrated on the figures, the heat core <NUM> can comprise two corridors. In this case, the corridor <NUM> defined by the second projection is a first corridor <NUM> and the first plate <NUM> has a third projection defining a second corridor <NUM>. Both the second projection and the third projection extend opposite of the internal housing <NUM>. When there are two corridors <NUM>, <NUM>, the first corridor <NUM> may be an extension of the first lateral side <NUM> of the liquid chamber <NUM> while the second corridor <NUM> is an extension of the second lateral side <NUM>. It is thus understood that the first and second corridors <NUM>, <NUM> are parallel and extend according to the longitudinal direction, each in the vicinity of one of the transverse ends of the first plate <NUM>.

As such, the first corridor <NUM> faces the first lateral liquid pass <NUM> whereas the second corridor <NUM> faces the second lateral liquid pass <NUM>. The presence of the corridors <NUM>, <NUM> and their disposition help improve coolant liquid flow in the lateral liquid passes <NUM>, <NUM>, thus preventing local boiling in these lateral liquid passes <NUM>, <NUM>.

As mentioned before, the first corridor <NUM> and the second corridor <NUM> extend in the direction of the second longitudinal end <NUM> of the heat core <NUM>. In some embodiments, the corridors <NUM>, <NUM> may extend up to this second longitudinal end <NUM>, whereas in other embodiments they do not extend all the way to of the second longitudinal end <NUM>; in other words, the length L of the corridors <NUM>, <NUM>, which is their dimension measured according to the longitudinal direction, may be reduced. The lengths L of the first corridor <NUM> and second corridor <NUM> have an impact on the cooling of the lateral liquid passes <NUM>; the longer they are, the better the lateral liquid passes <NUM> will avoid local boiling.

<FIG> illustrates a first plate <NUM> with reduced corridor lengths L. The first corridor <NUM> and second corridor <NUM> extend from the liquid chamber <NUM> and in the direction of the second longitudinal end <NUM> of the heat core <NUM>, up to about half of the first plate <NUM> according to the longitudinal direction. Conversely, the embodiments represented on <FIG> and <FIG> show the first and second corridors <NUM>, <NUM> extending further according to this longitudinal direction, that is to say that on these figures the corridors <NUM>, <NUM> have a greater length L. As an example, these first and second corridors <NUM>, <NUM> can here have a length L of about <NUM>.

More particularly, on <FIG> and <FIG> the first corridor <NUM> and the second corridor <NUM> extend up to a second liquid chamber <NUM>. This second liquid chamber <NUM> is defined by a fourth projection of the first plate <NUM>. While the liquid chamber <NUM> defined by the first projection, or first liquid chamber <NUM>, is located at the first longitudinal end <NUM> of the heat core <NUM>, this second liquid chamber <NUM> is located at the second longitudinal end <NUM> of the heat core <NUM>. First liquid chamber <NUM> and second liquid chamber <NUM> are joined by the first corridor <NUM> and the second corridor <NUM>.

In some embodiments, and as is the case on <FIG> and <FIG>, this second liquid chamber <NUM> may be blind. This means that a back wall <NUM> of the second liquid chamber <NUM>, extending mainly parallel to the plane portion of the first plate <NUM> and similar to the back wall <NUM> of the first liquid chamber, is not pierced with a hole. It is thus understood that this second liquid chamber <NUM> is not configured to bear either a coolant inlet or a coolant outlet.

The first corridor <NUM> and the second corridor <NUM> may have the same dimension measured according to the transverse direction of the heat exchanger <NUM>. This dimension corresponds to a width W of the first corridor <NUM> and the second corridor <NUM>. The corridors <NUM>, <NUM> having the same width helps ensure that the coolant liquid flows similarly on each side of the heat core <NUM>. As an example, the width W of the corridors <NUM>, <NUM> can be of about <NUM>.

In addition to the length L and the width W of the first and second corridors <NUM>, <NUM>, another factor influencing the flow of the coolant liquid within the heat core <NUM> is the height G of these corridors <NUM>, <NUM>, which will now be described in reference to <FIG>. Such height G of the corridors <NUM>, <NUM> corresponds to their dimension measured according to the vertical direction. In some embodiments, the height G of the first corridor <NUM> and of the second corridor <NUM> can be the same as the height H of the liquid chamber <NUM>. In other words, there is no increase or decrease between a section of the liquid chamber <NUM> and a section of either corridor <NUM>, <NUM>. Such embodiments are particularly visible on <FIG> and <FIG>, where the height G of the corridors <NUM>, <NUM> can be of about <NUM>,<NUM>. On the contrary, in other embodiments and as illustrated on <FIG>, the first plate <NUM> exhibits different sections for the liquid chamber <NUM> on the one hand and for the corridors <NUM>, <NUM> on the other hand. More precisely, the height G of the first corridor <NUM> and the second corridor <NUM> is reduced compared to that of the liquid chamber <NUM>. The height G of the corridors <NUM>, <NUM> can for instance be equal to half the height H of the liquid chamber <NUM>, or to a quarter of this height H. Such reduction in height compared to the liquid chamber <NUM> allows to control even better the flow of the coolant liquid within the heat core <NUM>.

The present invention thus covers a heat exchanger within which the flow of the coolant liquid, thus allowing an adequate cooling everywhere in the heat exchanger and more particularly in its lateral liquid passes.

Claim 1:
A heat exchanger (<NUM>) configured to cool an air flow with a coolant liquid, comprising a heat core (<NUM>), a first air flow duct located at a first longitudinal end (<NUM>) of said heat core (<NUM>) and a second air flow duct located at a second longitudinal end (<NUM>) of said heat core (<NUM>), the heat core (<NUM>) comprising a plurality of air flow channels (<NUM>) defining liquid passes (<NUM>, <NUM>, <NUM>, <NUM>) in between at least two air flow channels (<NUM>), said heat core (<NUM>) comprising a plurality of plates (<NUM>, <NUM>, <NUM>, <NUM>) enveloping the air flow channels (<NUM>) and the liquid passes (<NUM>, <NUM>, <NUM>, <NUM>), the heat exchanger (<NUM>) being characterised in that at least one of the plates (<NUM>) has at least a first projection defining a liquid chamber (<NUM>) at the first longitudinal end (<NUM>) of the heat core (<NUM>) and at least a second projection defining a corridor (<NUM>) connected to the liquid chamber (<NUM>) and configured for the circulation of the coolant liquid, the corridor (<NUM>) extending from the liquid chamber (<NUM>) and in the direction of the second longitudinal end (<NUM>) of the heat core (<NUM>).