Numerical simulation and performance evaluation of skin friction reduction by boundary layer injection under hypervelocity inflow condition

This study proposes a quantitative evaluation framework to assess the performance of boundary layer injection (BLI) technology, establishing standardized metrics for integration into performance analysis of scramjets. We comparatively evaluate inert gas and fuel BLI strategies under typical combusto...

Full description

Saved in:
Bibliographic Details
Main Authors: Zhenming Qu, Feiteng Luo, Yaosong Long, Wenjuan Chen
Format: Article
Language:English
Published: KeAi Communications Co., Ltd. 2025-06-01
Series:Propulsion and Power Research
Subjects:
Online Access:http://www.sciencedirect.com/science/article/pii/S2212540X25000239
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1850098095074836480
author Zhenming Qu
Feiteng Luo
Yaosong Long
Wenjuan Chen
author_facet Zhenming Qu
Feiteng Luo
Yaosong Long
Wenjuan Chen
author_sort Zhenming Qu
collection DOAJ
description This study proposes a quantitative evaluation framework to assess the performance of boundary layer injection (BLI) technology, establishing standardized metrics for integration into performance analysis of scramjets. We comparatively evaluate inert gas and fuel BLI strategies under typical combustor inflow conditions through systematic numerical investigations employing this evaluation framework. Key findings reveal that fuel injection demonstrates superior skin friction reduction efficacy compared to inert gases, especially hydrogen, achieving skin friction reduction performance up to 600 s at Mach 8+ conditions with an injection equivalence ratio (ER) of 0.1. Hydrogen's advantage arises from its inherently low density, coupled with combustion-induced density reduction in the log-law region. This dual mechanism suppresses turbulent momentum transport and attenuates skin friction through large-scale flow restructuring. However, when benchmarked against reacting mainstream flows without BLI, fuel injection efficacy diminishes significantly (100 s level) — local density reduction effects induced by boundary layer combustion are attenuated by mainstream heat release, limiting further momentum transport suppression and reducing drag reduction performance to inert gas levels. These results underscore the critical influence of ambient combustion conditions on BLI effectiveness, emphasizing that BLI implementation must prioritize non-reacting or weakly reacting flow environments. The proposed standardized metrics address this operational dependency, enabling BLI optimization within full-engine design paradigms to prevent counterproductive “pseudo-optimization.''
format Article
id doaj-art-06a2102c26fa4ee78151dce5096a2617
institution DOAJ
issn 2212-540X
language English
publishDate 2025-06-01
publisher KeAi Communications Co., Ltd.
record_format Article
series Propulsion and Power Research
spelling doaj-art-06a2102c26fa4ee78151dce5096a26172025-08-20T02:40:48ZengKeAi Communications Co., Ltd.Propulsion and Power Research2212-540X2025-06-0114227430310.1016/j.jppr.2025.05.003Numerical simulation and performance evaluation of skin friction reduction by boundary layer injection under hypervelocity inflow conditionZhenming Qu0Feiteng Luo1Yaosong Long2Wenjuan Chen3School of Aerospace Engineering, Huazhong University of Science and Technology, Wuhan, Hubei, ChinaCorresponding author.; School of Aerospace Engineering, Huazhong University of Science and Technology, Wuhan, Hubei, ChinaSchool of Aerospace Engineering, Huazhong University of Science and Technology, Wuhan, Hubei, ChinaSchool of Aerospace Engineering, Huazhong University of Science and Technology, Wuhan, Hubei, ChinaThis study proposes a quantitative evaluation framework to assess the performance of boundary layer injection (BLI) technology, establishing standardized metrics for integration into performance analysis of scramjets. We comparatively evaluate inert gas and fuel BLI strategies under typical combustor inflow conditions through systematic numerical investigations employing this evaluation framework. Key findings reveal that fuel injection demonstrates superior skin friction reduction efficacy compared to inert gases, especially hydrogen, achieving skin friction reduction performance up to 600 s at Mach 8+ conditions with an injection equivalence ratio (ER) of 0.1. Hydrogen's advantage arises from its inherently low density, coupled with combustion-induced density reduction in the log-law region. This dual mechanism suppresses turbulent momentum transport and attenuates skin friction through large-scale flow restructuring. However, when benchmarked against reacting mainstream flows without BLI, fuel injection efficacy diminishes significantly (100 s level) — local density reduction effects induced by boundary layer combustion are attenuated by mainstream heat release, limiting further momentum transport suppression and reducing drag reduction performance to inert gas levels. These results underscore the critical influence of ambient combustion conditions on BLI effectiveness, emphasizing that BLI implementation must prioritize non-reacting or weakly reacting flow environments. The proposed standardized metrics address this operational dependency, enabling BLI optimization within full-engine design paradigms to prevent counterproductive “pseudo-optimization.''http://www.sciencedirect.com/science/article/pii/S2212540X25000239ScramjetBoundary layer combustionBoundary layer injectionSkin friction reductionPerformance evaluationHypersonic
spellingShingle Zhenming Qu
Feiteng Luo
Yaosong Long
Wenjuan Chen
Numerical simulation and performance evaluation of skin friction reduction by boundary layer injection under hypervelocity inflow condition
Propulsion and Power Research
Scramjet
Boundary layer combustion
Boundary layer injection
Skin friction reduction
Performance evaluation
Hypersonic
title Numerical simulation and performance evaluation of skin friction reduction by boundary layer injection under hypervelocity inflow condition
title_full Numerical simulation and performance evaluation of skin friction reduction by boundary layer injection under hypervelocity inflow condition
title_fullStr Numerical simulation and performance evaluation of skin friction reduction by boundary layer injection under hypervelocity inflow condition
title_full_unstemmed Numerical simulation and performance evaluation of skin friction reduction by boundary layer injection under hypervelocity inflow condition
title_short Numerical simulation and performance evaluation of skin friction reduction by boundary layer injection under hypervelocity inflow condition
title_sort numerical simulation and performance evaluation of skin friction reduction by boundary layer injection under hypervelocity inflow condition
topic Scramjet
Boundary layer combustion
Boundary layer injection
Skin friction reduction
Performance evaluation
Hypersonic
url http://www.sciencedirect.com/science/article/pii/S2212540X25000239
work_keys_str_mv AT zhenmingqu numericalsimulationandperformanceevaluationofskinfrictionreductionbyboundarylayerinjectionunderhypervelocityinflowcondition
AT feitengluo numericalsimulationandperformanceevaluationofskinfrictionreductionbyboundarylayerinjectionunderhypervelocityinflowcondition
AT yaosonglong numericalsimulationandperformanceevaluationofskinfrictionreductionbyboundarylayerinjectionunderhypervelocityinflowcondition
AT wenjuanchen numericalsimulationandperformanceevaluationofskinfrictionreductionbyboundarylayerinjectionunderhypervelocityinflowcondition