On Sun, 20 May 2018 22:25:03 +0100, Steve Walker
wrote:

An RB211 (for industrial use) only has two compressor stages (medium and
high pressure), on two co-axial shafts, driven by two turbines -
probably because the air at ground level is dense and the first stage is
redundant. Again, the turbines are sized to power the appropriate
compressor stage and you get a lot of hot, fast moving exhaust. In this
use, it is actually termed a gas generator (or was by the company I
worked for) and you don't want the GG to move. Instead it is bolted down
and the exhaust is directed into a power-turbine, which is driven by the
gas, before exhausting to a heat recovery plant. The power-turbine
drives whatever load you have attached.

This sounds similar to the GT used in the Royal Navy destroyers that
broke down when they went in tropical waters, a problem with an inter
cooler.

The conversion efficiency was claimed to be better than a diesel at
over 50%

AJH