mike-wsm
Thin-walled high operating temperature heat exchanger and now methanol injection. This is one incredibly complex engine. What is the reliability over how many re-usage cycles?
Well, the methanol injection was ATREX, not SABRE or Scimitar. Regardless, yes, it is a very complicated engine.
I've had a chance to examine the references you gave and the spiral construction of the pre-cooler appears to be an attempt to make it behave like a
counterflow heat exchanger. A conventional counterflow heat exchanger is continuous in that one fluid is gradually heated along its length as the other fluid travelling in the opposite direction is gradually cooled, At all points along the heat exchanger the temperature difference between fluids is the same, yielding the best performance.
So, the air goes one way, and the coolant goes the opposite way?