Boeing patents self-transpiring cooling system for hot struc

[nuaetius]

<blockquote><font class="small">In reply to:</font><hr /><p>A self-transpiring technology for hypersonic or reusable space vehicles using a solid material that becomes gaseous and flows through the porous outer surface to cool the surface has been patented by Boeing.<br /><br />Boeing expects the technology to provide cooling over a temperature range of 600-1600ºC (1,100-2,900ºF). The solid material is held within an inner cavity between the support structure and ceramic matrix composite outer skin.<br /><br />The material vaporises, sublimes or decomposes into the gas at a temperature below the maximum the outer skin can withstand. Once a gas, it transpires through the porous outer surface to cool the skin. <br /><br />The patent states: "The solid material system is a non-regenerable resource, it is capable of protection for only a limited duration during a high heat flux event." But the material would be replaced between flights, it notes.<br /><p><hr /></p></p></blockquote> <br /><br />http://www.flightglobal.com/articles/2007/12/28/220343/boeing-patents-self-transpiring-cooling-system-for-hot.html

 

[spacy600]

Speaking of patents, Jim Benson <br />just applied for a new one.<br /><br />http://tinyurl.com/yu88e8<br />Single-Piece Hybrid Rocket Motor <br /><br />A hybrid rocket motor is formed from a single piece of material, such as, for example, by extrusion or injection molding. The rocket motor includes various components, such as casing, structure, oxidizer tank, combustion chamber, fuel, port and nozzle that are all formed from a single piece of material. The material can be, for example, a material that can be used as solid rocket fuel.

 

[keermalec]

I believe classic ablative aershells withstand temperatures up to 1600° C as well. Given this new technology is also non-reusable, it will not revolutionize the space industry. Now a fully reusable system (with no refurbishing necessary between flights ala Space Shuttle) now THAT would be a revolution. <div class="Discussion_UserSignature"> <p><em>“An error does not become a mistake until you refuse to correct it.” John F. Kennedy</em></p> </div>

 

[j05h]

If the material used for transpiration is water, then the heatshield could be refilled between flights or with space station gray water in LEO. Using orbital waste water could be a huge leverage in that instance. More exotic materials would probably require refurbishing. <br /><br />Josh <div class="Discussion_UserSignature"> <div align="center"><em>We need a first generation of pioneers.</em><br /></div> </div>

 

[spacy600]

From the patent:<br /><br />The material system contained within the internal cavity is an effective solid chemical that undergoes an endothermic reaction (or possibly even mildly exothermic) in the desired temperature range to produce gases that can penetrate the porous ceramic material as it is being generated. One material system that meets these requirements is zinc nitride. Another material system that meets these requirements is a mixture of germanium nitride and germanium oxide. In addition, mixtures of these two systems are also contemplated and may provide cooling over a customized temperature range from about 600 to 1600 degrees Celsius. Several other nitrides or oxynitrides are also contemplated. <br /><br />They talk of powder form (fine, coarse, ect)<br /><br />The proposed invention combines the attributes of an insulative and ablative thermal protection system into a single integrated system for a hypersonic or reusable space vehicle with the capability of surviving short periods of high heat flux (either planned in the flight profile or an off-nominal event) without sustaining structural damage due to overheating. The proposed invention is expected to be cost effective, and can extend the range of heat loads for insulative thermal protection systems.<br /><br />Looks like you can fill the powder and go.<br />