Stationary Rocket Engines

The rocket generators are functionally similar to gas turbines but with two key differences. The first key difference is that they require oxidizers to function, not just liquid and gaseous fuels. The second key difference is they have compact turbopumps inside, as they can pig out on fuel and oxidizer just like a real life rocket engine.

The turbopump used in these units are similar to the ones used in full-flow staged combustion cycles, but with interchangeable turbines, impellers and stators. The pumps can be rearranged to run in oxidizer-rich mode when using petrochemical fuels. (they coke when they get hot without sufficient oxidizer! you don’t want petrochemical coke ruining your fuel lines!)

All of that fuel and oxidizer being pumped by the turbopump goes into the combustion chamber, creating a small explosion that drives the main turbine, thus generating a lot of rotational energy.

One note about using ClF3 in turbopump impellers is the necessary passivation by fluorine gas if made of nickel, copper or steel … or by coating them with polychlorotrifluoroethylene plastic. The turbopump turbines in a ClF3-rich staged combustion cycle rocket engine is a different story, you just can’t coat them with PCTFE, which is a bummer as it limits your material choices for the turbopump turbines. (you can only use fluorine-passivated or ClF3-passivated nickel, copper or steel.) The stators can be passivated or coated depending on what side of the turbopump the stators are located. (impeller stators can be coated with special plastic while turbine stators can only be passivated.)

Polychlorotrifluoroethylene is a special plastic used to contain ClF3, made by reacting HDPE with a little ClF3 in special chemical reactors.

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