Supersonic nozzle flow simulations for particle coating applications: Effects of shockwaves, nozzle geometry, ambient pressure, and substrate location upon flow characteristics

Jung Jae Park, Min Wook Lee, Suk Goo Yoon, Ho Young Kim, Scott C. James, Stephen D. Heister, Sanjeev Chandra, Woon Ha Yoon, Dong Soo Park, Jungho Ryu

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28 Citations (Scopus)


Characteristics of supersonic flow are examined with specific regard to nano-particle thin-film coating. Effects of shockwaves, nozzle geometry, chamber pressure, and substrate location were studied computationally. Shockwaves are minimized to reduce fluctuations in flow properties at the discontinuities across diamond shock structures. Nozzle geometry was adjusted to ensure optimal expansion (i.e., P exit = P ambient), where shock formation was significantly reduced and flow kinetic energy maximized. When the ambient pressure was reduced from 1 to 0.01316 bar, the nozzle's diverging angle must be increased to yield the optimum condition of minimized adversed effects. Beyond some critical distance, substrate location did not seem to be a sensitive parameter on flow characteristics when P amb = 0.01316 bar; however, overly close proximity to the nozzle exit caused flow disturbances inside the nozzle, thereby adversely affecting coating gas flow.

Original languageEnglish
Pages (from-to)514-522
Number of pages9
JournalJournal of Thermal Spray Technology
Issue number3
Publication statusPublished - 2011 Mar 1



  • nano-particle coating
  • nozzle optimization
  • shockwave
  • supersonic flow
  • thin-film deposition

ASJC Scopus subject areas

  • Condensed Matter Physics
  • Materials Chemistry
  • Surfaces, Coatings and Films

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