Patent Application
20200003479
The subject matter disclosed herein generally relates to the field of fluid passage components, and more particularly to method and apparatus for reducing moisture in fluid passage components.
In an aircraft air condition system, moisture may condense and build up on air conditioning components. The moisture must be collected and drained from engine bleed air, or compressed ambient air, at a location downstream of a condenser to prevent re-entry into the cabin or air cycle machine where the moisture may cause damage.
According to one embodiment, a method of applying a hydrophobic surface coating to one or more internal surfaces of a fluid passage component is provided. The method including: flowing a rare earth precursor into the fluid passage component; allowing the rare earth precursor to react with the one or more internal surfaces of the fluid passage component; removing excess rare earth precursor from the fluid passage component; flowing an oxide forming precursor into the fluid passage component; allowing the oxide forming precursor to react with the rare earth precursors on the one or more internal surfaces to form a hydrophobic surface coating on each of the one or more internal surfaces; and removing excess oxide forming precursor from the fluid passage component.
In addition to one or more of the features described above, or as an alternative, further embodiments may include: flowing a rare earth precursor into the fluid passage component; allowing the rare earth precursor to react with the hydrophobic surface coating on each of the one or more internal surfaces of the fluid passage component; removing excess rare earth precursor from the fluid passage component; flowing an oxide forming precursor into the fluid passage component; allowing the oxide forming precursor to react with the rare earth precursors on the one or more internal surfaces to form a second layer of a hydrophobic surface coating on each of the one or more internal surfaces; and removing excess oxide forming precursor from the fluid passage component.
In addition to one or more of the features described above, or as an alternative, further embodiments may include that the rare earth precursor includes at least one of tetrakis(2,2,6,6-tetramethyl-3,5-heptanedionato)cerium, (tris(isopropylcyclopentadienyl)cerium, tris(2,2,6,6,-tetramethyl-3,5-heptanedionato)-1,10-phenanthroline)cerium, and tetrakis(1-methoxy-2-methyl-2-propanolate)cerium.
In addition to one or more of the features described above, or as an alternative, further embodiments may include that the oxide forming precursor includes at least one of water, ozone, and an O2 plasma.
In addition to one or more of the features described above, or as an alternative, further embodiments may include that the rare earth precursor is allowed to react with the one or more internal surfaces of the fluid passage component through vapor deposition.
In addition to one or more of the features described above, or as an alternative, further embodiments may include that the rare earth precursor is allowed to react with the one or more internal surfaces of the fluid passage component through chemical vapor deposition.
In addition to one or more of the features described above, or as an alternative, further embodiments may include that the rare earth precursor is allowed to react with the one or more internal surfaces of the fluid passage component through atomic layer deposition.
According to another embodiment, a fluid passage component having a hydrophobic surface coating on one or more internal surfaces of the fluid passage component formed by the method of claim 1 is provided. The fluid passage component including: an inlet; an outlet opposite the inlet; and an inner surface defining a main flow channel, the main flow channel fluidly connecting the inlet to the outlet, the inner surface is one of the one or more internal surfaces having a hydrophobic surface coating.
In addition to one or more of the features described above, or as an alternative, further embodiments may include the fluid passage component is a heat exchanger.
In addition to one or more of the features described above, or as an alternative, further embodiments may include that the fluid passage component is a heat exchanger of an air-conditioning system.
In addition to one or more of the features described above, or as an alternative, further embodiments may include that the fluid passage component is a heat exchanger of an air-conditioning system of an aircraft.
In addition to one or more of the features described above, or as an alternative, further embodiments may include that the fluid passage component is a condenser.
In addition to one or more of the features described above, or as an alternative, further embodiments may include that the fluid passage component is a condenser of an air-conditioning system.
In addition to one or more of the features described above, or as an alternative, further embodiments may include that the fluid passage component is a condenser of an air-conditioning system of an aircraft.
In addition to one or more of the features described above, or as an alternative, further embodiments may include: a cooling fluid passageway in thermal communication with airflow within the main flow channel, the cooling fluid passageway is one of the one or more internal surfaces having a hydrophobic surface coating.
In addition to one or more of the features described above, or as an alternative, further embodiments may include: a heat-transfer fin in thermal communication with airflow within the main flow channel, the heat-transfer fin is one of the one or more internal surfaces having a hydrophobic surface coating.
In addition to one or more of the features described above, or as an alternative, further embodiments may include that the hydrophobic surface coating includes at least one of cerium oxide, erbium oxide, and praseodymium oxide.
According to another embodiment, a fluid passage component is provided. The fluid passage component including: one or more internal surfaces having a hydrophobic surface coating on the one or more internal surfaces, the hydrophobic surface having an oxidized precursor layer bonded to a rare earth precursor layer.
In addition to one or more of the features described above, or as an alternative, further embodiments may include an inlet; an outlet opposite the inlet; and an inner surface defining a main flow channel, the main flow channel fluidly connecting the inlet to the outlet, wherein the inner surface is one of the one or more internal surfaces having a hydrophobic surface coating.
In addition to one or more of the features described above, or as an alternative, further embodiments may include that the fluid passage component is a heat exchanger.
Technical effects of embodiments of the present disclosure include adding a hydrophobic surface to a fluid passage component using atomic layer deposition.
The foregoing features and elements may be combined in various combinations without exclusivity, unless expressly indicated otherwise. These features and elements as well as the operation thereof will become more apparent in light of the following description and the accompanying drawings. It should be understood, however, that the following description and drawings are intended to be illustrative and explanatory in nature and non-limiting.
The following descriptions should not be considered limiting in any way. With reference to the accompanying drawings, like elements are numbered alike:
A detailed description of one or more embodiments of the disclosed apparatus and method are presented herein by way of exemplification and not limitation with reference to the Figures.
The air conditioning system 12, is a sub-system of an aircraft engine that conditions bleed air 14 so that bleed air 14 can be re-used to perform an additional function within the aircraft. The bleed air 14 is taken from a compressor stage 16 of the aircraft engine. In another non-limiting embodiment, the bleed air 14 can be compressed air taken from an ambient environment. The compressor stage 16 is an intermediate or high pressure stage within the aircraft engine. The condenser 18 is a heat exchanger for condensing moisture into droplets. In an embodiment, the fluid passage component 20 is the condenser 18 of the air conditioning system 12. The fluid passage component 20 includes a main flow channel 40 defined by an internal surface 38 of fluid passage component (see
The compressor stage 16 is fluidly connected to the condenser 18 via fluid lines or conduits in the aircraft. The condenser may be fluidly connected to the fluid passage component 20. The fluid passage component 20 may be fluidly connected to the air cycle machine 22, and the air cycle machine 22 is fluidly connected to the cabin 24.
During operation of the aircraft engine, bleed air 14 is drawn from the compressor stage 16 and into the condenser 18 of the air conditioning system 12. The condenser 18 condenses moisture in the bleed air 14 from vapor into moisture droplets. In some non-limiting embodiments, bleed air 14 can be conditioned by a heat exchanger in order to increase or decrease the temperature of the bleed air 14 exiting from the condenser 18. The bleed air 14, with the condensed moisture droplets, is then transported to the air cycle machine 22. The air cycle machine 22 further conditions the bleed air 14 by altering the temperature and the pressure of the bleed air 14 to a level appropriate from the passengers in the cabin 24. A more detailed example of an aircraft air conditioning system and/or an environment control system can be found in U.S. Pat. No. 8,347,647B2.
The fluid passage component 20 also includes a hydrophobic surface coating 42. In an embodiment, all internal surface 80 of the fluid passage component 20 may be coated with the hydrophobic surface coating 42. In another embodiment, the hydrophobic surface coating 42 is located on selected surfaces within the main flow channel 40 of the fluid passage component 20. In an embodiment, the hydrophobic surface coating 42 is located on the inner surface 38 of the main flow channel 40.
The hydrophobic surface coating 42 is configured to repel moisture away from the hydrophobic surface coating 42. The hydrophobic surface coating 42 may be composed of a hydrophobic compound including but not limited to rare earth oxides and phosphates (e.g., CeO2) that are naturally hydrophobic due to electron shielding of the unoccupied 4f orbitals. Rare earth oxides may include but are not limited to cerium oxide, erbium oxide, praseodymium oxide, or any rare earth oxide known to one of skill in the art. In an embodiment, the hydrophobic surface coating 42 includes at least one of cerium oxide, erbium oxide, and praseodymium oxide.
As mentioned above, the fluid passage component 20 may be a heat exchanger. Advantageously, since the hydrophobic surface coating 42 is configured to repel moisture away from the hydrophobic surface coating 42, the hydrophobic surface coating 42 would be ideal for coating interior surfaces 80 of a heat exchanger core 70 since the heat exchanger core 70 may drop the temperature of airflow 60, thus creating condensation from moisture in the airflow 60. In an embodiment, where the fluid passage component 20 is a heat exchanger, the fluid passage component 20 may include a heat exchanger core 70 located within the fluid passage component 20. The heat exchanger core 70 may designed in various configuration including a non-mixing shell and tube heat exchanger shown in
As shown in
As shown in
Referring now to
At block 410, an oxide forming precursor 120 is flowed into the fluid passage component 20. Specifically the oxide forming precursor 120 may be flowed into the main flow channel 40 of the fluid passage component 20. At block 412, the oxide forming precursor 120 is allowed to react with the rare earth precursors 110 on the one or more internal surfaces 80 to form a hydrophobic surface coating 42 on each of the one or more internal surfaces 80. The rare earth precursor may be water, ozone, or an O2 plasma. In an embodiment, the rare earth precursor includes at least one of water, ozone, and an O2 plasma. At block 414, the excess oxide forming precursor 120 is removed from the fluid passage component 20. For example, the excess oxide forming precursor 120 may be removed from the main flow channel 40 by vacuuming the excess oxide forming precursor 120 out of the main flow channel 40.
The method 400 may be repeated at block 416 to add more than one layer of hydrophobic surface coating 42 on each of the one or more internal surfaces 80. Upon adding a second layer of hydrophobic surface coating 42 at block 406 the rare earth precursor 110 will react with the previous layer of hydrophobic surface coating 42 on each of the one or more internal surfaces 80 rather than the internal surface 80, as described above when laying down the first layer of hydrophobic surface coating 42. The method 400 may be repeated multiple times at block 416 until a desired thickness of the hydrophobic surface coating 42 is obtained on each of the one or more internal surfaces 80. For example, a desired thickness may be 5-10 nm.
While the above description has described the flow process of
The term “about” is intended to include the degree of error associated with measurement of the particular quantity based upon the equipment available at the time of filing the application. For example, “about” can include a range of ±8% or 5%, or 2% of a given value.
The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the present disclosure. As used herein, the singular forms “a”, “an” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms “comprises” and/or “comprising,” when used in this specification, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, element components, and/or groups thereof.
While the present disclosure has been described with reference to an exemplary embodiment or embodiments, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted for elements thereof without departing from the scope of the present disclosure. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the present disclosure without departing from the essential scope thereof. Therefore, it is intended that the present disclosure not be limited to the particular embodiment disclosed as the best mode contemplated for carrying out this present disclosure, but that the present disclosure will include all embodiments falling within the scope of the claims,
