The Tupolev company has patented a hypersonic aircraft with a combined power plant. It includes two turbojet engines that use jet fuel and one that uses cryogenic fuel. The authors of the invention want to solve the problem of heating when flying at supersonic speeds when external surfaces interact with the incoming air flow, reports TASS.
In order to cool the external surfaces, “cryogenic fuel is supplied from the tank through pipelines to the hottest parts of the aircraft airframe and engine, as a result of which intensive gasification of cryogenic fuel occurs in the pipelines.” “This process is endothermic in nature, in which heat is absorbed from the heated parts of the aircraft airframe and engine. The heated cryogenic fuel turns into gaseous form and is fed into the engine combustion chamber and afterburner to create thrust,” the patent description says.
Thermally stable fuel T-6 or T-8B can be used as jet fuel, and liquefied natural gas or liquefied hydrogen can be used as cryogenic fuel.
One of the authors of the invention was Valery Benderov, Honored Designer of the Russian Federation, leading design engineer of the Tupolev Design Bureau. From 2012 to 2019, he was the program director and chief designer of the multifunctional flight simulation complex.