Patent Description:
Closed-loop environmental systems, such as the certain aircraft or spacecraft (e.g., the International Space Station), require water to be recycled and reused. This includes any water vapor that has been evaporated or exhaled inside of the system. A condensing heat exchanger has been used on spacecraft to control air temperature and humidity, and to extract excess water vapor from the air. The vapor condenses on the heat exchanger, adheres to its hydrophilic surface, and then is collected by a slurper. Typical slurpers, which separate and collect the water without diverting the air, may not operate with high efficiency due to material and design limitations. <CIT>, <CIT>, <CIT> and <CIT> are relevant prior art documents.

There is always a need in the art for improvements to water separation in condensing heat exchangers, for example in the aerospace industry. This disclosure provides a solution for this need.

In accordance with at least one aspect of this disclosure, a system includes a liquid-gas separator. The liquid-gas separator comprises, a substantially planar body configured to be seated in a fluid flow to separate a flow of liquid from the fluid flow, one or more apertures disposed in the body configured collect the flow of liquid, and one or more diverters integrally formed on or in the body configured divert the flow of liquid towards the one or more apertures. In certain embodiments, the planar body can be additively manufactured.

The one or more diverters include a pair of ramps angled oblique to a longitudinal axis of the planar body and diverging away from the planar body configured to direct the fluid flow over the pair of ramps and to separate the flow of liquid from the fluid flow and divert the flow of liquid between the pair of ramps. In certain embodiments, the pair of ramps can be arranged to form a chevron pattern, and a respective aperture of the one or more apertures is disposed at a converging point of the chevron pattern.

In certain embodiments the pair of ramps can be a first pair of ramps in a plurality of pairs of ramps, and the plurality of pairs of ramps can be disposed along an axial length of the planar body, forming a plurality of chevrons. In certain embodiments, the planar body can be a first planar body, and the system can include a second substantially planar body configured to be seated in the fluid flow opposite the first planar body forming a flow channel therebetween.

In certain such embodiments, the second planar body can include one or more apertures disposed in the second planar body configured collect a flow of liquid, and one or more diverters integrally formed on or in the second planar body configured to separate the flow of liquid from the fluid flow and divert the flow of liquid from towards the one or more apertures. The one or more diverters of the second planar body can include a plurality of pairs of ramps angled oblique to a longitudinal axis of the planar body and diverging away from the second planar body configured to direct the fluid flow over each ramp of the plurality of pairs of ramps and to separate the flow of liquid from the fluid flow and divert the flow of liquid between each the pair of ramps. Each pair of ramps of the second planar body can be arranged to form a chevron pattern, and a respective aperture of the one or more apertures of the second planar body can be disposed at a converging point of the chevron pattern. In embodiments, the plurality of pairs of ramps of the second planar body can be disposed along an axial length of the second planar body, and in certain embodiments, the plurality of pairs of ramps and plurality of apertures of the second planar body can be axially offset from the plurality of pairs of ramps and the plurality of apertures of the first planar body.

In certain embodiments, the one or more diverters can include a plurality of ramps arranged parallel to one another along an axial length of the planar body and diverging away from the planar body, the plurality of ramps configured to direct the fluid flow over each ramp of the plurality of ramps and to separate the flow of liquid from the fluid flow and divert the flow of liquid between each ramp of the plurality of ramps. In certain such embodiments, the one or more apertures can be disposed in an alternating pattern with the plurality of ramps.

In certain embodiments, the first planar body is a first planar body, and the system can also include a second substantially planar body configured to be seated in the fluid flow opposite the first planar body forming a flow channel therebetween. In certain such embodiments, the second planar body can include one or more apertures disposed in the second planar body configured collect a flow of liquid, and one or more diverters integrally formed on or in the second planar body configured divert the flow of liquid from towards the one or more apertures. The one or more diverters of the second planar body can include a plurality of ramps arranged parallel to one another along an axial length of the second planar body and diverging away from the planar body, the plurality of ramps of the second planar body configured to direct the fluid flow over each ramp of the plurality of ramps and to separate the flow of liquid from the fluid flow and divert the flow of liquid between each ramp of the plurality of ramps. In certain embodiments, the plurality ramps and plurality of apertures of the second planar body can be axially offset from the plurality of ramps and the plurality of apertures of the first planar body.

In certain embodiments, the one or more diverters can include a pair of ramps diverging away from the planar body and arranged such that an apex of each ramp in the pair of ramps are adjacent to one another and defining a trench therebetween. In certain such embodiments, the one or more diverters can be configured to direct the fluid flow over each apex of the pair of ramps and over the trench and to separate the flow of liquid from the fluid flow and divert the flow of liquid into the trench. In certain embodiments, the one or more apertures can be disposed at a bottom of the trench. In embodiments, a drop off angle between the apex of each ramp and a side wall of the trench can be about <NUM> degrees.

In certain embodiments, the planar body includes a plurality of diverters disposed along an axial length of the planar body. In embodiments, the planar body can be a first planar body, the system can include a second substantially planar body configured to be seated in the fluid flow opposite the first planar body forming a flow channel therebetween. The second planar body can include one or more apertures disposed in the second planar body configured collect a flow of liquid and one or more diverters integrally formed on or in the second planar body configured divert the flow of liquid from towards the one or more apertures.

In certain embodiments, the one or more diverters of the second planar body can include a pair of ramps diverging away from the second planar body and arranged such that an apex of each ramp in the pair of ramps are adjacent to one another and defining a trench therebetween, the one or more diverters of the second planar body configured to direct the fluid flow over each apex of the pair of ramps and over the trench and to separate the flow of liquid from the fluid flow and divert the flow of liquid into the trench. The second planar body can include a plurality of diverters disposed along an axial length of the second planar body, and in certain embodiments, the plurality of diverters of the second planar body can be axially offset from the diverters of the first planar body.

In certain embodiments, the one or more diverters can include a hydrophilic coating disposed on one or more portions of the planar body configured to separate the flow of liquid from the fluid flow and divert the flow of liquid towards the one or more apertures. In certain embodiments, the one or more diverters can include a hydrophobic coating disposed on one or more portions of the planar body configured to separate the flow of liquid from the fluid flow and divert the flow of liquid towards the one or more apertures.

In certain embodiments, the one or more diverters can include a divot defined in the planar body and converging into the planar body. In certain such embodiments, the one or more apertures can be disposed at a bottom of the divot, the trench configured to direct the fluid flow over the divot and to separate the flow of liquid from the fluid flow and divert the flow of liquid into the divot.

In certain embodiments, the planar body can include a hollow bar, and the one or more diverters can include a rounded edge of the hollow bar. In embodiments, the one or more apertures can include a plurality of apertures disposed along an axial length of the bar, and in certain embodiments, the plurality of apertures can be disposed in a face of the hollow bar parallel to the fluid flow. In embodiments, the one or more apertures can include a plurality of apertures disposed in a downstream edge of the hollow bar relative to the fluid flow to direct the fluid flow over the face of the planar body and configured to separate the flow of liquid from the fluid flow and divert the flow of liquid along the downstream edge of the hollow bar and into the plurality of apertures.

In embodiments, the system can include a heat exchanger body having a heat exchanger core. The heat exchanger core can include airflow gas flow path defined between a gas inlet and a gas outlet and a condensate flow path defined between the one or more apertures of the liquid-gas separator and a condensate outlet. The liquid-gas separator can be disposed in the heat exchanger core in the gas flow path, and in certain embodiments the liquid-gas separator can be formed integrally with or by the heat exchanger core. The liquid-gas separator can be configured to separate the flow of liquid from a flow of gas, direct the flow of gas to the gas outlet and divert the flow of liquid to through the apertures and to the condensate outlet. In certain embodiments, the heat exchanger body can include a cross flow heat exchanger body, and can further include a liquid flow path defined between a liquid inlet and a liquid outlet, wherein the liquid flow path is fluidly isolated from the gas flow path and the condensate flow path.

In embodiments, the liquid-gas separator can be configured separate the flow of liquid from a flow of gas, direct the flow of gas to the gas outlet and divert the flow of liquid through the apertures and to the condensate outlet in a weightless environment. In embodiments, the weightless environment can include a spacecraft in outer space.

Reference will now be made to the drawings wherein like reference numerals identify similar structural features or aspects of the subject disclosure. For purposes of explanation and illustration, and not limitation, an illustrative view of an embodiment of a system in accordance with the disclosure is shown in <FIG> and is designated generally by reference character <NUM>. Other embodiments and/or aspects of this disclosure are shown in <FIG>.

With reference to <FIG>, in accordance with at least one aspect of this disclosure, a system <NUM> includes a heat exchanger body <NUM> having a heat exchanger core <NUM>. The heat exchanger body <NUM> and core <NUM> can define, a gas flow path <NUM> defined between a gas inlet <NUM> and a gas outlet <NUM>. A condensate flow path <NUM> can be defined between one or more apertures <NUM> of a liquid-gas separator <NUM> and a condensate outlet <NUM>. The liquid-gas separator <NUM> can be disposed in the heat exchanger body <NUM> in a fluid flow path <NUM> (e.g., the gas flow path <NUM> having a mixture of liquid and gas therein).

In embodiments, the liquid-gas separator <NUM> can be configured to separate the fluid flow <NUM> into the flow of gas <NUM> and a flow of liquid <NUM>. The liquid-gas separator <NUM> can also be configured to direct the flow of gas <NUM> to the gas outlet <NUM> and divert the flow of liquid <NUM> from the fluid flow <NUM> to and through the apertures <NUM> and to the condensate outlet <NUM>. In certain embodiments, the heat exchanger body <NUM> can include a cross flow heat exchanger body, and can further include a liquid flow path <NUM> defined between a liquid inlet <NUM> and a liquid outlet <NUM>, wherein the liquid flow path <NUM> is fluidly isolated from gas flow path <NUM> and the condensate flow path <NUM>. In embodiments, the separator <NUM> can be configured to direct the flow of gas <NUM> to the gas outlet <NUM> and divert the flow of liquid <NUM> to and through the apertures <NUM> and to the condensate outlet <NUM> in a weightless environment, for example if the system <NUM> is included in a spacecraft <NUM> travelling to, from or within outer space at a constant velocity.

In certain embodiments, the liquid-gas separator <NUM> can be or include an air-water separator configured to separate a flow of air (e.g., gas flow <NUM>) and a flow of water (e.g., liquid flow <NUM>) from the fluid flow <NUM>. For clarity and ease of explanation, the liquid-gas separator <NUM> is hereinafter referred to as air-water separator <NUM>, and the respective flows therein are referred to as flow of air <NUM> and flow of water <NUM>. One skilled in the art having the benefit of this disclosure however would readily appreciate the separator <NUM> can be used for separating liquids and gases other than water and air as dictated by the particular heat exchanger or system with which it is used.

In certain embodiments, with reference now to <FIG>, the air-water separator <NUM> can include a substantially planar body <NUM> configured to be seated in the fluid flow <NUM> to separate the flow of water <NUM> from the flow of air <NUM> in the fluid flow <NUM>. The one or more apertures <NUM> can be disposed in the body <NUM> configured collect the flow of water <NUM>, and one or more diverters <NUM> can be integrally formed on or in the body <NUM> configured divert the flow of water <NUM> towards the one or more apertures <NUM>. In certain embodiments, the planar body <NUM> can be additively manufactured.

As shown in <FIG>, the one or more diverters <NUM> can include a pair of ramps <NUM> angled oblique to a longitudinal axis A of the planar body <NUM> and diverging away from the planar body <NUM> configured to direct the flow of air <NUM> over the pair of ramps <NUM> and to divert the flow of water <NUM> between the pair of ramps <NUM>. In certain embodiments, e.g., as shown, the pair of ramps <NUM> can be arranged to form a chevron pattern, and a respective aperture of the one or more apertures <NUM> can be disposed at a converging point <NUM> of the chevron pattern. While triangular ramps are shown, any suitable shaped ramp is contemplated herein, for example rounded triangular ramps. Further, the apertures <NUM> can be included in any suitable location along the axial length of the body <NUM> and in any suitable pattern with respect to the ramps <NUM>.

Still with reference to <FIG>, the pair of ramps <NUM> can be a first pair of ramps 228a in a plurality of pairs of ramps, and the plurality of pairs of ramps can be disposed along an axial length of the planar body <NUM>, forming a plurality of chevrons. In embodiments the planar body <NUM> can be a first planar body 224a, and the system can include a second substantially planar body 224b configured to be seated in the fluid flow <NUM> opposite the first planar body 224a forming a flow channel <NUM> therebetween.

As shown, the second planar body 224b can be substantially similar to the first planar body 224a. The plurality of pairs of ramps 228b and apertures 212b of the second planar body 224b can be disposed along an axial length of the second planar body 224b but can be axially offset from the plurality of pairs of ramps 228a and the plurality of apertures 212a of the first planar body 224a. As seen more clearly in <FIG>, the first and second planar bodies 224a, 224b can also be offset from each other in a direction perpendicular to the longitudinal axis A1, A2 of the first and second planar bodies 224a, 224b. The blockage in the fluid flow <NUM> created by the chevrons <NUM> will create a recirculation region for the airflow <NUM>, causing the bulk blow to travel up the ramps and impinge on the opposite wall.

With reference now to <FIG>, another embodiment of an air-water separator <NUM> is shown. The air-water separator <NUM> can be similar to that of the air-water separator <NUM>, for example air-water separator <NUM> can have similar components and features with respect to air-water separator <NUM>. For brevity, the description of common elements that have been described above for air-water separator <NUM> are not repeated with respect to air-water separator <NUM> as shown in <FIG>. In air-water separator <NUM>, the one or more diverters <NUM> can include a plurality of ramps <NUM> arranged parallel to one another along the axial length of the planar body <NUM> to direct the flow of air <NUM> over each ramp <NUM> and to divert the flow of water <NUM> between each ramp <NUM>. As shown, the one or more apertures <NUM> can be disposed in an alternating pattern with the plurality of ramps <NUM>.

As shown in <FIG>, the plurality of ramps 328b and plurality of apertures 312b of the second planar body 324b can be axially offset from the plurality of ramps 328a and the plurality of apertures 312a of the first planar body 324a and in a direction perpendicular to the longitudinal axis of the planar bodies 324a, 324b. Orienting the ramps <NUM> in the direction of the air flow <NUM> will reduce the pressure drop created by the obstruction. Axially offsetting the ramps on the top (e.g., 328b) and bottom (e.g., 328a) will impinge the air <NUM> onto the opposite surface and encourage the water <NUM> towards the holes <NUM>.

With reference now to <FIG>, another embodiment of an air-water separator <NUM> is shown. The air-water separator <NUM> can be similar to that of the air-water separators <NUM>, <NUM>, for example air-water separator <NUM> can have similar components and features with respect to air-water separators <NUM>, <NUM>. For brevity, the description of common elements that have been described above for air-water separators <NUM>, <NUM> are not repeated with respect to air-water separator <NUM> as shown in <FIG>. In air-water separator <NUM>, the one or more diverters <NUM> can include a pair of ramps <NUM> diverging away from the planar body 424a and arranged such that an apex <NUM> of each ramp <NUM> are adjacent to one another and define a trench <NUM> therebetween.

The one or more diverters <NUM> can be configured to direct the flow of air <NUM> over each apex <NUM> and over the trench <NUM> and to divert the flow of water <NUM> into the trench <NUM>. In certain embodiments, the one or more apertures <NUM> can be disposed at a bottom <NUM> of the trench <NUM>. In embodiments, a drop off angle <NUM> between the apex <NUM> of each ramp <NUM> and a side wall <NUM> of the trench <NUM> can be about <NUM> degrees. Here, the air <NUM> will pass over the trench <NUM>, because the Reynolds number of the air <NUM> will be too high to make the turn at the drop off angle <NUM> (e.g., in some case about <NUM> degrees). The water <NUM> will have a lower Reynolds number and will drop off into the trench <NUM>, where it can drain into the apertures <NUM>.

A second planar body 424b (e.g., substantially similar to the first planar body 424a) can be included opposite the first planar body forming a flow channel <NUM> therebetween. As shown in <FIG>, the plurality of diverters 426b of the second planar body 424b can be axially offset from the diverters 426a of the first planar body 424a. Because of the axial offset, the channel <NUM> will have the same height along the entirety of the fluid flow path within the heat exchanger body. In certain embodiments, the one or more apertures can be included in any suitable pattern relative to the trench <NUM> and the ramps <NUM>, for example, apertures <NUM> can additionally be included at the apex <NUM> of each ramp <NUM>. One or more additional obstructions may be included along the length of the trench <NUM> to guide the water <NUM> toward the apertures <NUM>.

For example, in certain embodiments, intermittent, discontinuous 'speed bumps' may be included where the speed bumps on an upstream and downstream side of the planar body are different heights. For example, if the speed bump on the downstream side of the planar body is taller than the upstream side, the downstream speed bump would catch any water droplets that are still in the air stream and may have deflected off of the upstream speed bump, and direct the water to the respective aperture. In contrast, if the speed bump on the upstream side is taller than the downstream side, a stronger low-pressure region would be formed in the valley between the upstream and downstream speed bumps, while not obstructing any downstream flow. One skilled in the art having the benefit of this disclosure would appreciate that feature size/shape of the diverters on the planar body can be optimized based on one or more conditions, such as flow rate, water content, water adherence to a given surfaces, fluid type, and the like.

With reference now to <FIG>, another embodiment of the air-water separator <NUM> is shown. The air-water separator <NUM> can be similar to that of the air-water separators <NUM>, <NUM>, <NUM>, for example air-water separator <NUM> can have similar components and features with respect to air-water separators <NUM>, <NUM>, <NUM>. For brevity, the description of common elements that have been described above for air-water separators <NUM>, <NUM>, <NUM> are not repeated with respect to air-water separator <NUM> as shown in <FIG>. In air water separator <NUM>, the one or more diverters <NUM> can include a divot <NUM> defined in the planar body <NUM> and converging into the planar body <NUM>. As shown, the one or more apertures <NUM> can be disposed at a bottom (e.g., the lowest point) of the divot <NUM>, the divot <NUM> configured to divert the flow of water <NUM> into the divot <NUM> and through the aperture <NUM> and to direct the flow of air <NUM> over the divot <NUM>.

The divot <NUM> can take any suitable shape, for example a flat rectangular recess as shown in <FIG>, a rectangular sloped recess converging into the planar body as shown in <FIG>, a trapezoidal sloped recess converging into the planar body as shown in <FIG>, or any suitable combination thereof. Additionally, while not shown, any one of air-water separators <NUM> as shown in <FIG> can include a second planar body positioned in the fluid flow opposite the first planar body to form a flow channel therebetween, the second planar body being offset from the first planar body in at least on direction (e.g., as described above with respect to air-water separators <NUM>, <NUM>, <NUM>.

With reference now to <FIG>, another embodiment of an air-water separator <NUM> is shown. The air-water separator <NUM> can be similar to that of the air-water separators <NUM>, <NUM>, <NUM>, <NUM>, for example air-water separator <NUM> can have similar components and features with respect to air-water separators <NUM>, <NUM>, <NUM>, <NUM>. For brevity, the description of common elements that have been described above for air-water separators <NUM>, <NUM>, <NUM>, <NUM> are not repeated with respect to air-water separator <NUM> as shown in <FIG>. In air-water separator <NUM>, the planar body <NUM> can include a hollow bar, and the one or more diverters <NUM> can include a rounded edge <NUM> of the hollow bar.

The one or more apertures <NUM> can include a plurality of apertures <NUM> disposed along an axial length of the bar <NUM> in at least one of a face <NUM> or an edge <NUM> of the hollow bar <NUM>. For example, the plurality of apertures <NUM> can be disposed in a face <NUM> of the hollow bar <NUM> parallel to the fluid flow <NUM> and airflow <NUM>. The one or more apertures <NUM> can additionally or alternatively include a plurality of apertures <NUM> disposed in a downstream edge (e.g., edge <NUM>) of the hollow bar <NUM> relative to the fluid flow <NUM> to direct the flow of air <NUM> over the face <NUM> of the planar body <NUM> and configured to divert the flow of water <NUM> along the downstream edge <NUM> of the bar <NUM> and into the plurality of apertures <NUM>. In embodiments, (e.g., as explained further below with respect to air-water separator <NUM>), the planar body <NUM> can include a hydrophilic coating or a hydrophobic coating. If the surface tension force from the hydrophilic coating outweighs the viscous force from the airflow <NUM>, the water <NUM> will remain attached to the bar <NUM> and collect on the back surface (e.g., downstream edge <NUM>) and enter apertures <NUM>.

With reference now to <FIG>, another embodiment of an air-water separator <NUM> is shown. The air-water separator <NUM> can be similar to that of the air-water separators <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, for example air-water separator <NUM> can have similar components and features with respect to air-water separators <NUM>, <NUM>, <NUM>, <NUM>, <NUM>. For brevity, the description of common elements that have been described above for air-water separators <NUM>, <NUM>, <NUM>, <NUM>, <NUM> are not repeated with respect to air-water separator <NUM> as shown in <FIG>. In air-water separator <NUM>, the one or more diverters <NUM> can include either or both of a hydrophilic <NUM> and/or a hydrophobic <NUM> coating disposed on one or more portions of the planar body <NUM> configured to divert the flow of water <NUM> towards the one or more apertures <NUM>.

For example, as shown, a hydrophilic coating <NUM> can be disposed on the planar body <NUM> in a triangular pattern, where a point <NUM> of the triangle converges on a respective aperture <NUM>. The remainder of the planar body <NUM> may be coated with the hydrophobic coating <NUM> to coax the water to the hydrophilic portions. The hydrophilic coating <NUM> can be selectively and strategically applied in a pattern that will help collect water <NUM> at the apertures <NUM>. It is contemplated that the embodiment of the air-water separator <NUM> of <FIG> can be used in any suitable combination with any of the air-water separators described herein, e.g., any one or more of air-water separators <NUM>, <NUM>, <NUM>, <NUM>, <NUM>.

In embodiments, one or more portions, or an entirety of the air-water separator can be formed using additive manufacturing, which allows for more complicated designs than the cast-in condensing heat exchangers. In embodiments, the air-water separator can be formed using laser powder bed fusion, including titanium laser powder bed fusion. One such design includes chevrons added to the slurper bar (e.g., planar body <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>) to direct water droplets towards the collection holes, and shaped to create re-circulation zones for the air to reduce the amount of air leakage into the slurper. Another design can include trenches added along the length of the slurper to collect the water in a slot that the air will pass over. Holes are drilled at the bottom of the trench to drain the water into the slurper channel. Another design includes adding patterns in the hydrophilic coating and holes on the leeward edge of the slurper bar take advantage of the surface tension forces from the water.

Claim 1:
A system, comprising:
a liquid-gas separator (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>) including,
a substantially planar body (<NUM>) configured to be seated in a fluid flow to separate a flow of liquid from the fluid flow;
one or more apertures (<NUM>) disposed in the body configured collect the flow of liquid; and
one or more diverters (<NUM>) integrally formed on or in the body configured to divert the flow of water towards the one or more apertures (<NUM>);
wherein the one or more diverters (<NUM>) includes a pair of ramps (<NUM>) angled oblique to a longitudinal axis of the planar body (<NUM>) and diverging away from the planar body configured to direct the fluid flow over the pair of ramps (<NUM>) and to separate the flow of liquid from the fluid flow and divert the flow of liquid between the pair of ramps (<NUM>).