At high speeds the compressor and turbine of the jet engine may be eliminated entirely. The result is called a ramjet (a subsonic configuration is shown). Here the incoming air is slowed and the pressure increases; the air is heated in the widest part by the burning of injected fuel. The heated air exhausts at high velocity from the converging nozzle. What nozzle area \(A_{2}\), is needed to deliver a \(90 \mathrm{kN}\) thrust at an air speed of \(270 \mathrm{~m} / \mathrm{s}\) if the exhaust velocity is the sonic velocity for the heated air, which is at \(1000 \mathrm{~K}\). How much fuel energy \((\mathrm{kW})\) is required? Assume that the jet operates at an altitude of \(12 \mathrm{~km}\) and neglect the fuel mass and pressure differentials.

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V V2 Nozzle X Fuel Jets Diffuser Combustion -- X P4.144