The kerosene-fueled Scramjet with multi-cavity combustor has the potential to serve aspropulsion system for hypersonic flight.However,the impact of injection positions on combustionperformance and mechanism at high Ma...The kerosene-fueled Scramjet with multi-cavity combustor has the potential to serve aspropulsion system for hypersonic flight.However,the impact of injection positions on combustionperformance and mechanism at high Mach numbers remains uncertain.Therefore,a comparativestudy was conducted using numerical methods to explore multi-cavity Scramjet combustor perfor-mance at a flight Mach number 7.0 with different injection positions.The combustor is equippedwith 6 cavities arranged in three groups along the flow direction,each consisting of two cavities per-pendicular to the flow.It is shown that the injection location significantly influences combustionperformance:Front-injection yields higher combustion efficiency than post-injection,but post-injection is advantageous for the intake start.Additionally,regardless of injection positions,themainstream flow state near the cavities behind the injection can be categorized as supersonic flow,supersonic-subsonic coexistence flow,and subsonic flow.The optimal length from the downstreamto the trailing edge of the cavities behind the injection for achieving maximum combustion effi-ciency is determined.Further extension beyond this optimal length does not significantly increasethe combustion efficiency.In addition,the optimal length varies with different injection positions-specifically,it is about 60%longer with post-injection conditions than with front-injection con-ditions in this investigation.Moreover,significant secondary combustion within the cavities leadingto improved efficiency only occurs when mainstream flow state is either supersonic flow orsupersonic-subsonic coexistence flow.Also,with a well-optimized design,the kerosene-fueledmulti-cavity Scramjet can achieve enhanced combustion efficiency,which shows relatively smallvariation across a wide range of equivalence ratios.This might be caused by the effects of interac-tion among these multiple cavities.Therefore,these research findings can provide valuable insightsfor designing and optimizing the kerosene-fueled multi-cavity combustor in Scramjet at high Machnumbers.展开更多
基金financially supported by the National Key Laboratory of Ramjet,China(No.2022-020-003)the Fundamental Research Funds for the Central Universities,China(No.501QYZX2023146001)。
文摘The kerosene-fueled Scramjet with multi-cavity combustor has the potential to serve aspropulsion system for hypersonic flight.However,the impact of injection positions on combustionperformance and mechanism at high Mach numbers remains uncertain.Therefore,a comparativestudy was conducted using numerical methods to explore multi-cavity Scramjet combustor perfor-mance at a flight Mach number 7.0 with different injection positions.The combustor is equippedwith 6 cavities arranged in three groups along the flow direction,each consisting of two cavities per-pendicular to the flow.It is shown that the injection location significantly influences combustionperformance:Front-injection yields higher combustion efficiency than post-injection,but post-injection is advantageous for the intake start.Additionally,regardless of injection positions,themainstream flow state near the cavities behind the injection can be categorized as supersonic flow,supersonic-subsonic coexistence flow,and subsonic flow.The optimal length from the downstreamto the trailing edge of the cavities behind the injection for achieving maximum combustion effi-ciency is determined.Further extension beyond this optimal length does not significantly increasethe combustion efficiency.In addition,the optimal length varies with different injection positions-specifically,it is about 60%longer with post-injection conditions than with front-injection con-ditions in this investigation.Moreover,significant secondary combustion within the cavities leadingto improved efficiency only occurs when mainstream flow state is either supersonic flow orsupersonic-subsonic coexistence flow.Also,with a well-optimized design,the kerosene-fueledmulti-cavity Scramjet can achieve enhanced combustion efficiency,which shows relatively smallvariation across a wide range of equivalence ratios.This might be caused by the effects of interac-tion among these multiple cavities.Therefore,these research findings can provide valuable insightsfor designing and optimizing the kerosene-fueled multi-cavity combustor in Scramjet at high Machnumbers.
