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2026 Vol.31, Issue 1 Preview Page

Research Article

Numerical Investigation of Regression Rate and Combustion Characteristics of Fuel-Rich Propellant in Ramjet Combustor under Varying Inlet Conditions

램제트 연소기 입구 조건에 따른 연료과농 추진제의 후퇴율 및 연소 특성에 관한 수치해석 연구

Eunchong Kim1
,
Lin Yun2
,
Iksoo Park3
,
Sangwook Jin3
,
Doheon Kim3
,
Jaehoon Ryu3
,
Hanseul Shim4
,
Hyung Sub Sim2†
김 은총1
,
윤 린2
,
박 익수3
,
진 상욱3
,
김 도헌3
,
류 재훈3
,
심 한슬4
,
심 형섭2†
1Department of Aerospace Systems Engineering, Graduate School, Sejong University
2Department of Aerospace Engineering, Korea Advanced Institute of Science and Technology
3The 4th R&D Institute, Agency for Defense Development
4Department of Aerospace Systems Engineering, Sejong University
1세종대학교 대학원 우주항공시스템공학과
2한국과학기술원 항공우주공학과
3국방과학연구소 제4기술연구원
4세종대학교 우주항공시스템공학부
*Corresponding Author
31 March 2026. pp. 19-28
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Abstract

The regression rate of solid fuel is a critical performance parameter in solid-fuel ramjets, directly influencing thrust, specific impulse, and range. Therefore, accurate prediction of regression rate is essential for the design and optimization of solid-fuel ramjet propulsion systems. In this study, a coupled numerical framework combining condensed-phase pyrolysis and gas-phase combustion was developed to predict the regression rate and combustion characteristics of a fuel-rich propellant for solid-fuel ramjet applications. The regression rate was computed based on convective heat transfer from the flame and the Arrhenius-type pyrolysis relationship. Systematic analysis was conducted to examine the effects of inlet air mass flux and temperature on fuel regression and combustion performance. The predicted regression rate showed good agreement with experimental data, validating the proposed model. The results revealed that the local regression rate peaked near the reattachment point and gradually decreased downstream. Furthermore, increasing the air mass flux and temperature led to a higher regression rate. A regression rate correlation was derived, demonstrating that both air temperature and mass flux significantly influence the fuel regression rate.

Keywords
Solid fuel ramjet
Computational fluid dynamics
Regression rate
Combustion characteristics
Slab combustor
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Information
  • Publisher :The Korean Society of Combustion
  • Publisher(Ko) :한국연소학회
  • Journal Title :Journal of the Korean Society of Combustion
  • Journal Title(Ko) :한국연소학회지
  • Volume : 31
  • No :1
  • Pages :19-28
  • Received Date : 2026-01-26
  • Revised Date : 2026-03-09
  • Accepted Date : 2026-03-09
  • DOI :https://doi.org/10.15231/jksc.2026.31.1.019
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