The invention discloses a clean
skin substrate preparation method based on throttling expansion induced cooling
devitrification multiphase
jet flow, and belongs to the technical field of
aviation maintenance. The method comprises: firstly planning a
nozzle scanning path; then the mechanical arm and the
nozzle assembly are adjusted to initial positions; thirdly, compressed gas is introduced into the self-rotating
nozzle assembly, the saturated
salt solution is sucked in, the compressed gas is throttled and expanded through a Laval nozzle to generate low temperature, the
salt solution is induced to be cooled, crystals are separated out, and gas-liquid-
crystal three-phase
jet flow is formed; and finally, the spray head is driven to move along the track, and the three-phase
jet flow is used for cleaning the outer side coaming, the
front edge lip and the silencing plate of the aircraft air
inlet channel. According to the method, the crystals separated out in situ by cooling are used as the
abrasive medium, no residue exists after cleaning, the problems of
abrasive embedding,
thermal damage and chemical damage in a traditional method are thoroughly avoided, the clean
skin base body can be efficiently and controllably prepared, and an innovative solution is provided for maintenance and preparation of the clean
skin base body of the aircraft air
inlet channel.