jp928
Well-Known Member
Correct re kero - catches fire on exit from a pipe if rate is too high. One of Bernoulli's formulae covers the observation of the reduction in cross section of a fluid flow as its velocity increases - think of the vertical flow of water from a tap as it accelerates under gravity. Apparently this involves the speed of sound in the fluid, and this leads to the effect that the reduction in sectional area is inverted if the fluid exceeds the speed of sound, and the area increases again. Hence the gas turbine - the working fluid (air basically)must be accelerated from below speed of sound to above, so that it expands and produces thrust. This involves a lot of work in supersonic craft to reduce the speed of the air in the intakes to below the speed of sound before it hits the turbines.