How can you prevent the combustion chamber of a jet engine from melting at full throttle?

Question

What material is used? How is it made?

Answer 1

at high load or even at moderate load any metal cannot withstand that high temp,even though you provide air cooling that's not enough that is why the combustor and even the turbine blades for that matter have thermal coating called TBC(thermal barrier coating).These coatings serve to insulate metallic components from large and prolonged heat loads by utilizing thermally insulating materials which can sustain an appreciable temperature difference between the load bearing alloys and the coating surface

http://en.wikipedia.org/wiki/Thermal_bar...

Answer 2

Here's a few ideas...

First way is to reduce the transfer of heat to the inside surfaces of the combustion chamber (This often improves efficiency too, as more the engines heat is being thrown at the turbine!). Perhaps to reduce conduction, make sure there is ALWAYS a layer of cooler air between the VERY hot gas and the chamber walls. One way this can be done (which relies on a special kind of Convection) is to make the air rotate around the chamber's axis (the flow out from turbines often has some degree of swirl anyway, so it may as well be used). The heavier (and cooler) gasses will be displace the lighter gases, and the lighter/hotter gases will tend towards the centre of the chamber.(It's to do with Centripetal force, works much like a centrifuge) Radiant heat is a little more difficult, not sure if you want a reflective surface, or a matt-black one, but one of them will help. Different surface textures absorb different amounts of heat too. Think the smoother the surface the less area to absorb/radiate heat (there's a balance point that depends on conditions/materials)

Second is remove the heat from the chamber walls. perhaps pass a coolant though the cylinder walls to remove heat. Quite often fuel is pre-heated, and it can form part of a cooling system

Third is choice of material. An obvious choice to cope with high temperatures are refractories. Some of them can be cast, where as some require sintering.

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If you're trying to build one yourself perhaps try this link which suggests a way of using a lot of off the shelf parts (or out of a  scrap yard at least)

http://www.salvatoreaiello.com/main.shtm...

Answer 3

There are no jet engines on the market that melt at full throttle.

So you are trying to design your own? A major project.