Just Google e.g. "heat pipe" and "leading edge" or "thermal protection" and you'll get things like this:KJ_Lesnick said:I'm not sure if it said anything about being useful as a complete thermal protection system, or if it would only be useful as part of it.
KJ_Lesnick said:What I'm not getting is...
-A heat pipe works on convection; it carries heat from one area to another.
-How does that not heat up the insides of the plane?
KJ_Lesnick said:BTW: Has anyone heard of some kind of stuff called "Starlite" or "Firepaste"? Starlite was some kind of coating which allegedly was ceramic based and could allegedly take temperatures of 10,000 F to 20,000 F so I was told. I remember hearing of an experiment in which a hard-boiled egg was treated with this stuff then put under a (acetylene?) blow-torch. After they were done they cracked open the egg and the egg was unscathed. Firepaste is cruder and simpler and less capable but nonetheless is based on the same principle and works quite well. Since the stuff isn't exactly rigid or hard and capable of withstanding extreme stress... in combination with a fairly light heat-shield this stuff would be incredible.
sferrin said:Because you dump the heat into the fuel headed to the engines. There are limits to that however. One other use for that heat can be used to "crack" heavy hydrocarbon fuel into something "lighter" that lights off quicker for use in a scramjet. X-51 does this as I recall.
If you feel like looking through a decade's worth of AvWeek there was an ad in the 80s advertising coatings that could survice "particle beams and temperatures up to 50,000 degrees". Whether it was BS, someone added an extra zero or what have you I don't know. I do find it extremely hard to believe as carbon vaporizes at around 7000F and I don't see how you could take element A & element B and combine them to get a compound/alloy that has a higher melting point than either. Any chemists/metallurgists feel free to correct me.
(edit: Actually, table salt would fall into that category. Hmmmm.)