Water-based polymer networks for blow-off cooling applications

Abstract

The method includes obtaining (402) thermal energy from a structure (112) to be cooled, the structure including microchannels (208). The method also includes supplying (402) the thermal energy to a water-based polymer network (206), the water-based polymer network including a gel formed using a polymer and water. The method further includes generating (404) one or more gases (210) by heating the water-based polymer network, the generating one or more gases including releasing water in the water-based polymer network to produce steam. Additionally, the method includes passing (408) the one or more gases through the microchannels to remove at least a portion of the thermal energy from the structure.

Description

[Technical Field]

[0001] The present disclosure relates generally to cooling systems, and more particularly to water-based polymer networks for blow-off cooling applications. [Background technology]

[0002] Certain types of flying vehicles are capable of traveling through the atmosphere at very high speeds. As a result, some of these flying vehicles may experience extreme temperatures due to friction with the air. Without some thermal management, these extreme temperatures may damage or destroy components of the flying vehicle, preventing or preventing the flying vehicle from being used for its intended purpose. Summary of the Invention

[0003] The present disclosure provides water-based polymer networks for blow-off cooling applications.

[0004] In a first embodiment, a method includes obtaining thermal energy from a structure to be cooled, the structure including microchannels. The method also includes providing the thermal energy to a water-based polymer network, the water-based polymer network including a gel formed using a polymer and water. The method further includes generating one or more gases by heating the water-based polymer network, where generating the one or more gases includes releasing water in the water-based polymer network to produce steam. Additionally, the method includes passing the one or more gases through the microchannels to remove at least a portion of the thermal energy from the structure.

[0005] In a second embodiment, an apparatus includes a structure to be cooled, the structure including microchannels. The apparatus also includes a water-based polymer network configured to receive thermal energy from the structure. The water-based polymer network includes a gel formed using a polymer and water. The water-based polymer network is configured to generate one or more gases when heated, the one or more gases including water in the water-based polymer network liberated into steam. The microchannels are configured to allow the passage of the one or more gases to remove at least a portion of the thermal energy from the structure.

[0006] In a third embodiment, a flight vehicle includes a body having a leading edge, the leading edge including an external structure having microchannels. The flight vehicle also includes a water-based polymer network configured to receive thermal energy from the leading edge. The water-based polymer network includes a gel formed using a polymer and water. The water-based polymer network is configured to generate one or more gases when heated, the one or more gases including water in the water-based polymer network liberated into steam. The microchannels are configured to allow the passage of the one or more gases to remove at least a portion of the thermal energy from the leading edge.

[0007] Other technical features may be readily apparent to those skilled in the art from the following drawings, descriptions, and claims. [Brief explanation of the drawings]

[0008] For a more complete understanding of the present disclosure, reference is now made to the following descriptions taken in conjunction with the accompanying drawings, in which:

[0009] [Figure 1] 1 illustrates an exemplary flight vehicle supporting a water-based polymer network according to the present disclosure. [Figure 2] 1 illustrates an exemplary nose cone of a flight vehicle supporting a water-based polymer network according to the present disclosure. [Figure 3]1 illustrates an exemplary nose cone of a flight vehicle supporting a water-based polymer network according to the present disclosure. [Figure 4] 1 illustrates an exemplary method for using a water-based polymer network for blow-off cooling applications according to the present disclosure. DETAILED DESCRIPTION OF THE INVENTION

[0010] 1A-4 described below and the various embodiments used to explain the principles of the present disclosure are exemplary only and should not be construed as limiting the scope of the present disclosure. Those skilled in the art will understand that the principles of the present disclosure may be implemented in any type of suitably configured device or system.

[0011] As discussed above, certain types of air vehicles are capable of traveling through the atmosphere at very high speeds. As a result, some of these air vehicles may experience extreme temperatures due to friction with the air. Without some form of thermal management, these extreme temperatures may damage or destroy components of the air vehicle, preventing or rendering the air vehicle unable to be used for its intended purpose.

[0012] Some thermal management approaches attempt to use exotic materials that can withstand elevated temperatures. For example, carbon-carbon composites can generally be prone to ablation, and exotic coatings may be used to help protect the carbon-carbon composites. However, these approaches are typically expensive and not suitable for widespread manufacturing. Other approaches to thermal management may use heat pumps and other active thermal management techniques, but these approaches generally consume power and occupy significant space within the flight vehicle or other system.

[0013] The present disclosure provides a water-based polymer network for transpirant cooling applications. As described in more detail below, the transpirant coolant is implemented in the form of a gel, which includes a polymer (such as sodium polyacrylate) that has absorbed water. This effectively gels the water and, using osmosis, equilibrates sodium or other ions to form a polymer network. The polymer network in the gel does not decompose upon heating to produce liquid water. Instead, the water within the gel is released to produce a gas, such as steam, that can be used during the transpirant cooling process. Furthermore, the polymer itself may decompose into one or more gases (such as hydrogen gas) that are useful for transpirant purposes; this decomposition may represent an endothermic process that further functions as a potential cooling process. Optionally, one or more other liquids or solids may be mixed or dissolved in the water absorbed by the polymer network, and these one or more other liquids or solids may decompose into one or more useful gases for transpirant cooling purposes.

[0014] The gel becomes a stable, self-contained blow-off coolant and can be used in flight vehicles or other applications to cool the nose cone or other portions of the flight vehicle or other system. Furthermore, the gel can be easily injected into the nose cone or other portions of the flight vehicle or other system, allowing the gel to utilize all available space within the flight vehicle or other system. Furthermore, the gel can be relatively thick and act like a solid material when no significant external forces are acting on the gel, meaning that the gel can often function as a deformable solid. This allows the gel to remain in a desired location within the flight vehicle or other system. Furthermore, in some cases, microchannels or other passages through which gas can exit the nose cone or other portions of the flight vehicle or other system can be selectively sealed, for example, by using valves or one or more materials that can melt or liquefy at elevated temperatures. This can help reduce or prevent evaporation of water from the gel until it is used for blow-off cooling.

[0015] Finally, this approach supports the use of water within the gel for cooling purposes. In many cases, using water as a coolant is highly desirable due to its ability to rapidly remove large amounts of thermal energy. However, water has a tendency to leak through microchannels or other passages, which can cause problems for various devices (e.g., devices containing electronic circuitry). Furthermore, even if a microchannel or other passage is temporarily sealed, internal vapor pressure typically eventually forces all liquid water out of a given space, preventing the liquid water from evaporating and removing the maximum amount of thermal energy from an aircraft vehicle or other system. Using the gel as a blow-off coolant can help reduce or eliminate the possibility of water leakage, thereby enabling effective cooling using water without the risk of water leakage. Furthermore, internal pressure typically cannot force the gel through the microchannels, helping to keep the gel (and its associated water) in a suitable position for cooling purposes.

[0016] The water-based polymer network can be used for effusion cooling in any suitable device or system. In the following description, it is often assumed that the water-based polymer network is used in a flight vehicle, such as a rocket, missile, hypersonic vehicle, or other airborne system. Also, in the following description, it is often assumed that the water-based polymer network is used in the nose cone of the flight vehicle. However, this example of the use of the water-based polymer network is for illustrative purposes only. In general, the water-based polymer network can be used in any other suitable device or system where effusion cooling is required or desired, and the water-based polymer network can be used in any suitable portion or portions of those devices or systems.

[0017] FIG. 1 illustrates an exemplary aerial vehicle 100 supporting a water-based polymer network according to the present disclosure. As illustrated in FIG. 1, aerial vehicle 100 generally represents an object that flies through, is launched into or toward, or otherwise moves within a given space. Aerial vehicle 100 can represent a vehicle that moves through the atmosphere, or possibly space. Exemplary types of aerial vehicles can include projectiles, rockets, missiles, drones, aircraft, satellites, and spacecraft. Aerial vehicle 100 includes any suitable object configured to operate in a high-temperature environment.

[0018] In this particular example, flight vehicle 100 represents a hypersonic vehicle, which typically refers to an object capable of traveling at a speed of at least Mach 5 (approximately 3,836 miles per hour or approximately 6,174 kilometers per hour). In such hypersonic vehicles, friction caused by vehicle 100 passing through the atmosphere can generate a large amount of heat within vehicle 100. Note that the form factor of flight vehicle 100 shown in FIG. 1 is for illustrative purposes only. Numerous hypersonic vehicle designs have been proposed, and the present disclosure is not limited to any designs specifically for hypersonic vehicles. Furthermore, the present disclosure is not limited to use with hypersonic vehicles. For example, any vehicle or other object that may generate heat due to aerodynamic drag can be used herein, or any object that would otherwise generate sufficient heat or be used in a high-temperature environment can be used herein.

[0019] As can be seen in FIG. 1 , the flight vehicle 100 includes a body 102 that generally surrounds the other components of the flight vehicle 100. The body 102 can have any suitable size, shape, and dimensions. In a hypersonic flight vehicle, for example, the body 102 has an advanced aerodynamic shape that allows the flight vehicle 100 to travel through the atmosphere at extremely high speeds. Of course, the design of the body 102 can vary greatly based on the intended application. The body 102 can also be formed from any suitable material. Depending on the application and environment in which the body 102 will be used, the body 102 can be formed from exotic materials that can withstand extreme high temperatures. However, this is not required, and the body 102 can be formed from more common materials that can still withstand the intended temperatures of a given application. Furthermore, the body 102 can be formed in any suitable manner.

[0020] The flight vehicle 100 also includes various components, at least some of which may reside partially or completely within the body 102 of the flight vehicle 100. For example, the flight vehicle 100 may include one or more engine components 104, which generally represent components used to generate thrust to propel the flight vehicle 100. The engine components 104 may include any suitable type of engine, such as a ramjet or scramjet. The flight vehicle 100 may also include one or more guidance components 106 that may be used to help guide the flight vehicle 100 during flight. The guidance components 106 may include any suitable type of location detection or guidance system, such as a Global Positioning System (GPS) receiver or other satellite-based or other location detection system. The flight vehicle 100 may also include one or more tracking components 108 that may be used to track one or more objects or areas with which the flight vehicle 100 may collide. The tracking components 108 may include any suitable type of object or other tracking system, such as an electro-optical (EO) tracking system. Additionally, flight vehicle 100 may include one or more electrical components 110 that may be used to process data, control other components of flight vehicle 100, or perform other functions within flight vehicle 100. Electrical component 110 may include any suitable type of processing, control, or other electrical or electronic device, such as a microprocessor, microcontroller, digital signal processor (DSP), field programmable gate array (FPGA), application specific integrated circuit (ASIC), or discrete circuitry.

[0021] As described in more detail below, flight vehicle 100 uses a water-based polymer network to assist in vent cooling of flight vehicle 100 during use. The water-based polymer network may be used in any suitable portion or portions of flight vehicle 100 where cooling is needed or desired. In some cases, the water-based polymer network may be used in nosecone 112 of flight vehicle 100, for example, along the leading edge of nosecone 112. Nosecone 112 represents the leading end of flight vehicle 100 and may often represent the portion of flight vehicle 100 that reaches the highest temperature during flight. Nosecone 112 may be attached to or integrated with body 102 of flight vehicle 100. However, it should be noted that the water-based polymer network may be used in any other or additional portions of flight vehicle 100, for example, at or near an inlet or control surface of flight vehicle 100, or along the leading edge of at least one other structure or portion of flight vehicle 100 (such as a wing or fin).

[0022] While Figure 1 illustrates one example of an airborne vehicle 100 supporting a water-based polymer network, various modifications may be made to Figure 1. For example, any other suitable device or system may include one or more exemplary water-based polymer networks. Other exemplary applications in which one or more exemplary water-based polymer networks may be used include missiles, commercial or military rockets, or other commercial or military airborne vehicles. Additionally, the water-based polymer networks may be used in other environments and are not limited to use with airborne vehicles.

[0023] 2 and 3 illustrate an exemplary nose cone 112 of an air vehicle supporting a water-based polymer network in accordance with the present disclosure. For ease of explanation, the nose cone 112 is described as forming part of the air vehicle 100 shown in FIG. 1. However, the water-based polymer network may be used in any other suitable device or system, including other types of air vehicles.

[0024] As shown in FIG. 2 , the nosecone 112 is defined by a skin or other external structure 202. The external structure 202 generally represents the portion of the nosecone 112 that comes into contact with atmospheric air during movement. Thus, during use of the flight vehicle 100, the external structure 202 experiences a significant heat flux 204 that can rapidly heat the nosecone 112 and, absent some thermal management, may damage or destroy the nosecone 112. The external structure 202 of the nosecone 112 may be formed from any suitable material(s), such as a refractory alloy. The external structure 202 of the nosecone 112 may also be formed by any suitable method. Additionally, the external structure 202 of the nosecone 112 may have any suitable size, shape, and dimensions.

[0025] The water-based polymer network 206 is positioned within the nosecone 112 and can receive thermal energy from the nosecone 112 or other source(s). The water-based polymer network 206 represents a gel formed using a water-absorbing polymer that gels the water. Any suitable polymer, such as sodium polyacrylate, can be used herein to form the gel. The water-based polymer network 206 can fill any desired space or spaces within the nosecone 112 or other structure. In this example, the water-based polymer network 206 is shown as substantially filling the space at the end of the nosecone 112. However, the water-based polymer network 206 may have any other suitable form within the nosecone 112. Although not shown here, the nosecone 112 may define one or more dedicated compartments or other spaces within the nosecone 112 to hold the water-based polymer network 206.

[0026] During use, thermal energy from the nosecone 112 enters the water-based polymer network 206 and can liberate water within the water-based polymer network 206 into one or more gases, such as steam. Additionally, the polymers in the water-based polymer network 206 can undergo endothermic reactions to generate one or more additional gases, such as hydrogen gas. The microchannels 208 within the external structure 202 allow these various gases 210 to escape through the external structure 202 to the surrounding environment. Creating the gases 210 from the material of the water-based polymer network 206 and transporting the gases 210 through the microchannels 208 to the surrounding environment supports a blow-off cooling process (and optionally a convective heat transfer cooling process) that can remove a significant amount of thermal energy from the nosecone 112. Each microchannel 208 generally represents any suitable passageway through which gases can escape during the blow-off cooling process. Additionally, each microchannel 208 may be formed in any suitable manner. Furthermore, each microchannel 208 may have any suitable size, shape, and dimensions, and may follow any suitable path through the external structure 202 .

[0027] One or more additional materials 212 may optionally be used within the water-based polymer network 206. In some embodiments, for example, the one or more additional materials 212 may be mixed with or dissolved in water that is absorbed by the polymer network. These one or more additional materials 212 may also absorb thermal energy to generate one or more additional gases, which may escape through the external structure 202 via the microchannels 208 as additional gas 210. The one or more additional materials 212 may represent any suitable material or materials used to impart a desired functionality to the water-based polymer network 206, such as one or more liquid materials or one or more solid materials. For example, in some cases, the one or more additional materials 212 may include a glycol, which can be added to water to adjust the freezing point of the resulting mixture. The one or more additional materials 212 may also or instead include one or more salts, such as an ammonia salt.

[0028] As shown in FIG. 3 , an additional function that may optionally be employed by the water-based polymer network 206 includes selectively blocking microchannels 208. In the example shown in FIG. 3 , for example, material 302 may be positioned within each microchannel 208 to block that microchannel 208. This may help prevent water or other material(s) within the water-based polymer network 206 from evaporating or otherwise escaping through the microchannels 208 and out of the water-based polymer network 206 until the flight vehicle 100 or other system is actually in use. As a specific example, material 302 may be solid at lower temperatures but melt or otherwise liquefy at elevated temperatures. As a result, when the water and possibly other material(s) within the water-based polymer network 206 begin to form one or more gases 210 during use of the flight vehicle 100 or other system, internal pressure from the one or more gases 210 may eventually force the liquefied material 302 out of the microchannels 208. This then allows the one or more gases 210 to escape from within the nosecone 112 to the surrounding environment. The material 302 comprises any suitable material(s) configured to temporarily block the microchannels 208, such as paraffin wax or solder. It should be noted that while the use of a liquefiable material 302 represents one example of a mechanism for selectively blocking the microchannels 208, other mechanisms may also be used. For example, one or more valves 304 may be used to selectively open or block the microchannels 208.

[0029] In some embodiments, the water-based polymer network 206 used in the flight vehicle 100 or other system may be replaceable. For example, the flight vehicle 100 or other system may be put into operation, and the water-based polymer network 206 may be used to provide thermal management for the flight vehicle 100 or other system. If the flight vehicle 100 or other system is recovered, another water-based polymer network 206 may be injected or otherwise placed into the flight vehicle 100 or other system, allowing the flight vehicle 100 or other system to be used again. In other embodiments, the nosecone 112, or other portion of the flight vehicle 100, or other system including the water-based polymer network 206, may be replaceable. Thus, if the flight vehicle 100 or other system is recovered after use, another nosecone 112, or other portion of the flight vehicle 100, or other system including a different water-based polymer network 206 can be installed in the flight vehicle 100 or other system. Note, however, that this is not necessarily required, such as if a particular flight vehicle or other system cannot be reused.

[0030] 2 and 3 illustrate an example of a nose cone 112 of a flight vehicle 100 supporting a water-based polymer network 206, various modifications may be made to Figures 2 and 3. For example, the relative sizes, shapes, and dimensions of the components illustrated in Figures 2 and 3 may be varied as needed or desired. Additionally, the water-based polymer network 206 may be used in other environments and is not limited to use with a flight vehicle's nose cone 112 in particular, or with flight vehicles in general.

[0031] 4 illustrates an exemplary method 400 for using a water-based polymer network for blow-off cooling applications in accordance with the present disclosure. For ease of explanation, the method 400 is described as being performed within the flight vehicle 100 of FIG. 1 with the nose cone 112 of FIG. 2 and FIG. 3. However, the method 400 may be performed using any other suitable device or system that includes the water-based polymer network 206.

[0032] As shown in FIG. 4 , in step 402, the water-based polymer network receives thermal energy from the structure to be cooled. This may include, for example, the water-based polymer network 206 receiving thermal energy from the nose cone 112 of the flight vehicle 100. The water-based polymer network 206 includes a gel formed by at least one polymer and absorbed water (and optionally one or more additional materials 212). In step 404, the water-based polymer network is used to generate one or more gases. This may include, for example, heating the water-based polymer network 206 using thermal energy. This may also include liberating water in the water-based polymer network 206 into steam or other gas(es) 210. Further optionally, this may include the polymers in the water-based polymer network 206 undergoing an endothermic reaction to produce hydrogen gas or other gas(es) 210. Additionally, this may include one or more additional materials 212 (such as glycols or salts) in the water-based polymer network 206 generating the one or more additional gas(es) 210.

[0033] At step 406, the microchannels in the structure may optionally be unblocked. This may include melting or otherwise liquefying the material 302 blocking the microchannels 208, such as by thermal energy in the nose cone 112 of the flight vehicle 100. This may also include internal pressure within the nose cone 112 of the flight vehicle 100 forcing the liquefied material 302 out of the microchannels 208. In other embodiments, this may include opening one or more valves 304 to unblock the microchannels 208. At step 408, one or more gases are exhausted from the structure through the microchannels. This may include, for example, gas 210 escaping the nose cone 112 of the flight vehicle 100 through the microchannels 208. This may result in blow-off cooling of the structure at step 410 to remove thermal energy from the structure.

[0034] While Figure 4 illustrates an example method 400 for using a water-based polymer network for blow-off cooling applications, various modifications may be made to Figure 4. For example, although shown as a series of steps, the various steps in Figure 4 may overlap, occur in parallel, occur in a different order, or occur any number of times.

[0035] The following describes exemplary embodiments of the present disclosure that implement or relate to water-based polymer networks for blow-off cooling applications, although other embodiments may also be used in accordance with the teachings of the present disclosure.

[0036] In a first embodiment, a method includes obtaining thermal energy from a structure to be cooled, the structure including microchannels. The method also includes providing the thermal energy to a water-based polymer network, the water-based polymer network including a gel formed using a polymer and water. The method further includes generating one or more gases by heating the water-based polymer network, where generating the one or more gases includes releasing water in the water-based polymer network to produce steam. Additionally, the method includes passing the one or more gases through the microchannels to remove at least a portion of the thermal energy from the structure.

[0037] In a second embodiment, an apparatus includes a structure to be cooled, the structure including microchannels. The apparatus also includes a water-based polymer network configured to receive thermal energy from the structure. The water-based polymer network includes a gel formed using a polymer and water. The water-based polymer network is configured to generate one or more gases when heated, the one or more gases including water in the water-based polymer network that is released into steam. The microchannels are configured to allow the passage of the one or more gases to remove at least a portion of the thermal energy from the structure.

[0038] In a third embodiment, a flight vehicle includes a body having a leading edge, the leading edge including an external structure having microchannels. The flight vehicle also includes a water-based polymer network configured to receive thermal energy from the leading edge. The water-based polymer network includes a gel formed using a polymer and water. The water-based polymer network is configured to generate one or more gases when heated, the one or more gases including water in the water-based polymer network that is released into steam. The microchannels are configured to allow the passage of the one or more gases to remove at least a portion of the thermal energy from the leading edge.

[0039] Any single or suitable combination of the following features may be used with the first, second, or third embodiment. The one or more gases may further include one or more additional gases based on an endothermic reaction involving a polymer in the water-based polymer network. The gel may further include at least one additional material mixed or dissolved in water, and the one or more gases may further include one or more additional gases based on the at least one additional material. The at least one additional material may include at least one of a glycol and a salt. The polymer may include sodium polyacrylate. The water-based polymer network may not decompose or produce liquid water when heated by thermal energy. The microchannels may be unblocked to allow one or more gases to pass through the microchannels. Materials blocking the microchannels may be liquefied and forced out of the microchannels, unblocking the microchannels. One or more valves may be used to unblock the microchannels. The cooled structure may include a leading edge of a body of a flight vehicle. The body of the flight vehicle may include a nosecone, the leading edge may be associated with the nosecone, and the water-based polymer network may be positioned within the nosecone. The water-based polymer network within the nosecone may be replaceable, or the nosecone with the water-based polymer network may be replaceable.

[0040] It may be advantageous to provide definitions of certain words and phrases used throughout this patent document. The terms "include" and "comprise," as well as their derivatives, mean including without limitation. The term "or" is inclusive and / or. The term "associated with" and its derivatives may mean including, contained within, interconnected with, containing, housed within, connected to or with, coupled to or with, communicable with, associated with, interleaved with, juxtaposed with, proximate to, bound to or with, having, having properties of, relating to or with, and the like. The phrase "at least one of," when used in conjunction with a list of items, means that different combinations of one or more of the listed items may be used, and that only one item in the list may be required. For example, "at least one of A, B, and C" includes any of the following combinations: A, B, C, A and B, A and C, B and C, and A and B and C.

[0041] Nothing in this application should be read as implying that any particular element, step, or function is a required or critical element required for inclusion within the scope of any claim. The scope of patented subject matter is defined solely by the scope of the allowed claims. Furthermore, no claim shall invoke 35 U.S.C. §112(f) with respect to any of the appended claims or claim elements unless the precise phrase "means for" or "step for" is expressly used in a particular claim, followed by a participial phrase identifying the function. The use of terms such as "mechanism," "module," "device," "unit," "component," "element," "member," "apparatus," "machine," "system," "processor," or "controller" in the claims is understood to and intended to refer to structures known to those skilled in the art, as further modified or enhanced by features of the claims themselves, and is not intended to invoke 35 U.S.C. §112(f).

[0042] While this disclosure has described particular embodiments and generally associated methods, alterations and permutations of these embodiments and methods will be apparent to those skilled in the art. Accordingly, the above description of exemplary embodiments does not define or constrain the disclosure. Other changes, substitutions, and alterations are possible without departing from the spirit and scope of the disclosure, as defined by the following claims.

Claims

1. obtaining thermal energy from a structure to be cooled, the structure including microchannels; providing the thermal energy to a water-based polymer network, the water-based polymer network comprising a gel formed using a polymer and water; generating one or more gases by heating the water-based polymer network, wherein generating the one or more gases comprises releasing the water in the water-based polymer network to produce steam; passing the one or more gases through the microchannels to remove at least a portion of the thermal energy from the structure; A method comprising:

2. 10. The method of claim 1, wherein generating the one or more gases further comprises producing one or more additional gases based on an endothermic reaction involving the polymer in the water-based polymer network.

3. the gel further comprises at least one additional material mixed or dissolved in the water; The method of claim 1 , wherein generating the one or more gases further comprises producing one or more additional gases based on the at least one additional material.

4. The method of claim 3 , wherein the at least one additional material comprises at least one of a glycol and a salt.

5. The method of claim 1 , wherein the polymer comprises sodium polyacrylate.

6. 10. The method of claim 1, wherein the water-based polymer network does not decompose and does not produce liquid water when heated by the thermal energy.

7. The method of claim 1 , further comprising unblocking the microchannel to allow the one or more gases to pass through the microchannel.

8. unblocking the microchannels liquefying a material blocking the microchannel and forcing the liquefied material out of the microchannel; unblocking said microchannel using one or more valves; The method of claim 7, comprising one of:

9. a structure to be cooled, the structure including microchannels; a water-based polymer network configured to receive thermal energy from the structure, the water-based polymer network comprising a gel formed using a polymer and water, the water-based polymer network configured to generate one or more gases when heated, the one or more gases including the water in the water-based polymer network liberated into steam; Including, The apparatus, wherein the microchannels are configured to allow passage of the one or more gases to remove at least a portion of the thermal energy from the structure.

10. 10. The apparatus of claim 9, wherein the one or more gases further comprise one or more additional gases based on an endothermic reaction involving the polymer in the water-based polymer network.

11. the gel further comprises at least one additional material mixed or dissolved in the water; The apparatus of claim 9 , wherein the one or more gases further comprise one or more additional gases based on the at least one additional material.

12. The device of claim 11 , wherein the at least one additional material comprises at least one of a glycol and a salt.

13. The device of claim 9 , wherein the polymer comprises sodium polyacrylate.

14. 10. The device of claim 9, further comprising a material configured to block the microchannel until liquefied and extruded from the microchannel.

15. The apparatus of claim 9 , further comprising one or more valves configured to block and unblock the microchannels.

16. a body including a leading edge, the leading edge including an exterior structure having microchannels; a water-based polymer network configured to receive thermal energy from the leading edge, the water-based polymer network comprising a gel formed using a polymer and water, the water-based polymer network configured to generate one or more gases upon heating, the one or more gases including the water in the water-based polymer network liberated into steam; Including, the microchannels are configured to allow passage of the one or more gases to remove at least a portion of the thermal energy from the leading edge. Flying vehicle.

17. the one or more gases further comprising one or more additional gases based on an endothermic reaction involving the polymer in the water-based polymer network; The gel further comprises at least one additional material mixed or dissolved in the water, and the one or more gases further comprise one or more additional gases based on the at least one additional material; 17. The flight vehicle of claim 16, wherein the flight vehicle is at least one of:

18. 17. The flight vehicle of claim 16, wherein the polymer comprises sodium polyacrylate.

19. a material configured to block the microchannel until liquefied and extruded from the microchannel; one or more valves configured to block and unblock the microchannel; 17. The flight vehicle of claim 16, further comprising one of:

20. the body includes a nosecone; the leading edge is associated with the nosecone; the water-based polymer network is positioned within the nosecone; 17. The flight vehicle of claim 16.

21. the water-based polymer network in the nose cone is replaceable; and the nose cone with the water-based polymer network is replaceable; and 21. The flight vehicle of claim 20, wherein the flight vehicle is one of:

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