How to Protect Hypersonic Vehicles from High Temperatures?
A hypersonic flight can radically change the field of aeronautics, just as the overcoming of the sound barrier did in 1947. However, the transition from supersonic to hypersonic speeds has proven to be a much more challenging task. The main obstacle lies in the tremendous amount of heat generated by an object flying at five times the speed of sound, where most materials either melt or become inoperable.
Engineers at the RTX Center for Technology have been working to find a solution to this problem. Under a contract with DARPA, they propose an alternative method for cooling hypersonic vehicles by replicating the mechanism of human sweating. The idea involves integrating a network of microchannels into the front edges of the vehicle, similar to sweat glands in humans. These channels would supply liquid to the surface of the vehicle’s shell, which would then evaporate and remove heat.
John Sharon, the head of the project at RTX, has revealed that they have created a small-scale model, about the size of a credit card, for testing purposes. The next step entails refining the technology by reducing the size of the channels and scaling up the model to match the size of a real hypersonic vehicle.
“When you’re flying at five times the speed of sound, the temperature can increase rapidly, sometimes within a fraction of a second,” explained Sharon.