Journal of the Korean Society of Propulsion Engineers (한국추진공학회지)

The Korean Society of Propulsion Engineers (한국추진공학회)
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Heat Flux Measurements in High Velocity Oxygen-Fuel Torch Flow for Testing High Thermal Materials

고온 재료 테스트를 위한 고속 산소 연료 토치 흐름에서의 열유속 측정

  • Chinnaraj, Rajesh Kumar (High-Enthalpy Plasma Research Center, Jeonbuk National University) ;
  • Choi, Seong Man (High-Enthalpy Plasma Research Center, Jeonbuk National University) ;
  • Hong, Seong Min (High-Enthalpy Plasma Research Center, Jeonbuk National University)
  • Received : 2020.07.24
  • Accepted : 2021.02.06
  • Published : 2021.04.30
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Abstract

A commercial HVOF torch (originally designed for coating applications) has been modified as a high temperature flow source for material testing. In this study, a water cooled commercial Gardon gauge was used to measure heat fluxes at four locations away from the nozzle exit. The cooling water temperature data were used to calculate calorimetric heat fluxes at the same locations. The heat fluxes from both methods were compared and the calorimetric heat fluxes were found to be many times higher than the Gardon gauge heat fluxes. A hypothesis is applied to the calorimetric method to understand the discrepancy seen between the methods. The Gardon gauge heat fluxes are seen to be in the range of the hypothesized calorimetric calculations. This can be considered as a considerable validation for the hypothesis, but further refinement needed using appropriate numerical models.

상업용 HVOF 토치 (원래 코팅 용도로 설계됨)가 재료 테스트를 위한 고온 유동원으로 수정되었다. 이 연구에서는 수냉식 상용 Gardon 게이지를 사용하여 노즐 출구에서 떨어진 네 위치에서 열유속을 측정하였다. 냉각수 온도 데이터는 동일한 위치에서 열량 측정 열유속 (calorimetric heat flux)을 계산하는 데 사용되었다. 두 방법의 열유속을 비교 한 결과 열량 측정 열유속이 Gardon 게이지 열유속보다 몇 배 더 높은 것으로 나타났다. 두 가지 방법 사이에 나타나는 불일치를 이해하기 위해 열량 측정방법에 대한 가설을 적용하였다. 이것은 가설에 대한 상당한 검증으로 간주될 수 있지만 적절한 수치모델을 사용하여 추가 개선이 필요하다.

Keywords

Acknowledgement

This research was supported by Korea Basic Science Institute (National Research Facilities and Equipment Center) grant funded by the Ministry of Education (2019R1A6C1030013).

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