The document discusses water injection into an airbreathing jet engine with an afterburner. It provides thermodynamic data at 7 points for the engine flow path and 4 curves showing relative thrust versus relative water injection rate with fuel flow rates labeled on each curve. Water injection after the turbine but before the afterburner is identified as beneficial for this engine configuration.

1. Dear Leonard!
More than one year ago I have sent you an investigation of water injection process
using airbreathing jet engine as a workbench. Results were negative and I was
feeling some discomfort in our relations because I could not find any pearl in your
patents. Reasoning that it is my fault I continued to suffer in silence. Actually I do
understand something in the thermodynamics of gas turbine, but of the ground
versions not the airborne ones. In the power generation I’m sure that the water
injection is beneficial upstream of burner, not after.
Departing from this point of view I found at last the beautiful example of
beneficial water injection after turbine – it is the case of airbreathing jet engine
with afterburner.
The same layout as in my last message
Position p, MPa T, K h, kJ/kg G, g/s
1 0.127 346.4 349.5 1000.00
2 3.400 935.8 980.3 1000.00
3 3.400 298.2 2431.3 20.26
4 3.400 1600.0 1009.1 1020.26
5 0.542 1103.3 391.1 1020.26
6 3.400 298.2 2431.3 0.00
7 0.542 1103.3 391.1 1020.26
Here are 4 curves: relative thrust versus relative mass flow rate of injected water.
Figures on the curves – relative fuel rate in the afterburner.
Fuel
2
GT
Air
K
H2O
To
nozzle
1
3
4 5
6
7
0.94
0.96
0.98
1
1.02
1.04
1.06
1.08
1.1
1.12
0 0.1 0.2 0.3 0.4 0.5 0.6
0 0.2
0.4
0.7