Journal of ILASS-Korea (한국분무공학회지)

Institute for Liquid Atomization and Spray Systems-Korea (한국분무공학회)
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A Study on the Post Processing of Flash Boiling Spray Image from Shadowgraphy

감압비등 분무의 역광이미지 후처리 기법에 관한 연구

  • Hyunchang Lee
  • 이현창 (경남대학교 기계공학부)
  • Received : 2024.06.08
  • Accepted : 2024.06.21
  • Published : 2024.06.30
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Abstract

When investigating the droplet, spray, and impact of liquid on a solid plate, backlight imaging has been widely used to understand these phenomena. However, some previous studies have suffered from poor image quality. In this study, various combinations of image processing algorithms, such as white image correction, histogram equalization, CLAHE, Otsu's binarization, and multi-Otsu's binarization, have been applied to flash boiling spray images to enhance image quality for qualitative observation and semi-quantitative spray angle evaluation. To acquire images with high contrast for qualitative observation, applying CLAHE was effective, making small droplets and detailed shapes of the jet noticeable. However, when images were averaged to determine spray angle or penetration length based on intensity, this method induced artifact unphysical patterns, thus requiring careful consideration. Based on the algorithm proposed in this study, the spray angle variation according to injection pressure and temperature has been calculated, showing a reasonable trend.

Keywords

Acknowledgement

이 연구결과물은 2023학년도 경남대학교 신진교수연구비 지원에 의한 것임.

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