Transactions of the Korean Society of Mechanical Engineers B (대한기계학회논문집B)

The Korean Society of Mechanical Engineers (대한기계학회)
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Study of Micro-Supersonic Impinging Jets and Its Application to the Laser Machining

마이크로 초음속제트의 충돌유동과 레이저 가공 응용에 관한 연구

  • 민성규 (한국항공대학교 대학원 항공우주 및 기계공학과) ;
  • 유동옥 (한국항공대학교 항공우주 및 기계공학부) ;
  • 이열 (한국항공대학교 항공우주 및 기계공학부) ;
  • 정조순 (충남대학교 기계공학과)
  • Published : 2009.02.01
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Abstract

Characteristics of micro-sonic/supersonic axi-symmetric jet impinging on a flat plate with a pre-drilled hole were both experimentally and numerically studied, to observe the role of assist-gas jet to eject melted materials from the cut zone in the laser machining. For various Mach numbers of the nozzle and the total pressures of the assist gas, detailed impinging jet flow structures over the plate and the variations of mass flux through the pre-drilled hole were observed. It was found that the present experimental and numerical results show a good agreement, which proves the accountability of the present work. From the present study, it was also observed that the mass flow rate through the hole was closely related with the total pressure loss caused by the Mach disc on the work piece, and that supersonic nozzle could perform more efficient roles as blowing the assist-gas jet in the laser machining, as compared to sonic nozzles.

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References

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