I don't get it. They are injecting methanol on the outside of the precooler tubes right? What causes it to move opposite to the airflow? Capillary/wetting action?
>A heat exchanger as claimed in claim 93, wherein the antifreeze injector comprises a plurality of injection portions and is arranged to inject a more concentrated antifreeze at a first injection portion in a first region of air flow and a more water-diluted antifreeze at a second injection portion which is more upstream than the first injection portion at a second region of air flow that is warmer than the first region.
So I think they have system than repeatedly injects and collects the methanol and methanol/water mixture, re-injecting it each time upstream of the previous injection point.
They seem to inject it at the end, collect it somehow, then inject it upstream of the first injection location, then collect it again, then inject again upstream of that...
No clue how they perform this collection action, though.