内涵喷管关键几何参数对巡航工况超大涵道比短舱气动性能的影响研究  

Effects of core nozzle key geometric parameters on aerodynamic performance of ultra-high bypass ratio nacelle at cruise condition

作　　者：汪文杰 王占学[2] 邓文剑[2] WANG Wenjie;WANG Zhanxue;DENG Wenjian(Xi’an Modern Chemistry Research Institute,Xi’an 710065,China;School of Power and Energy,Northwestern Polytechnical University,Xi’an 710129,China)

机构地区：[1]西安近代化学研究所,陕西西安710065 [2]西北工业大学动力与能源学院,陕西西安710129

出　　处：《推进技术》2024年第7期62-76,共15页Journal of Propulsion Technology

基　　金：两机基础科学中心项目;超音速民机飞发匹配项目的支持。

摘　　要：为降低燃油消耗、污染物排放和气动噪声,民用涡扇发动机朝着超大涵道比(Ultra-High Bypass Ratio,UHBPR)方向发展。发动机尺寸增大导致的短舱阻力和质量增大会减小甚至抵消涵道比增大带来的收益。为进一步提升UHBPR短舱的气动性能,建立了评价巡航工况进气道、外罩和排气系统整体气动性能的参数,基于数值模拟研究了内涵喷管关键几何参数对短舱气动性能的影响规律,并分析了影响机理。结果表明:核心后罩收缩比和内涵喷管长径比对发动机安装推力损失的影响较大,最大变化量分别为10.77%和13.40%。核心后罩收缩比取较小值,内涵喷管长径比取值在0.9附近有利于减小发动机的安装推力损失。流场分析表明:核心后罩收缩比、内涵喷管长径比和出口角变化会影响外涵喷管出口下游的激波前马赫数、激波位置、强度以及其与附面层的相互干扰,也会影响尾锥附近的压力分布,还会影响内涵喷管出口马赫数,从而显著影响核心后罩推力、尾锥推力和内涵喷管推力。巡航工况下外涵喷管超临界而内涵喷管亚临界,内涵喷管几何参数变化几乎不会影响外涵喷管的性能,但会显著影响内涵喷管的流量和推力。内涵喷管流通能力的变化会影响发动机的流量,进而影响冲压阻力、附加阻力和外罩阻力。To reduce fuel consumption,pollution emissions,and aerodynamic noises further,the civil tur-bofan develops toward ultra-high bypass ratio(UHBPR).The increase of drag and weight of the nacelle caused by increasing engine size will decrease or counteract even the benefits brought by increasing the bypass ratio.To improve nacelle aerodynamic performance further,the overall performance parameter of the inlet,cowl,and ex-haust system was defined firstly.And the influence of key geometric parameters of the core nozzle on the aerody-namic performance of the UHBPR nacelle was conducted and the related flow mechanism was analyzed.The re-sults show that the contraction ratio of the core cowl and the length-diameter ratio of the core nozzle have an obvi-ous effect on the engine thrust loss caused by the UHBPR nacelle and the maximum variation of thrust loss is 10.77%and 13.40%respectively.The smaller contraction ratio of the core cowl and the length-diameter ratio of around 0.9 are favourable for decreasing the thrust loss.The change of the contraction ratio of the core cowl,the length-diameter ratio,and the core nozzle exit angle can affect the issues including the Mach number before the shock wave,the location and strength of the shock wave,and shock wave-boundary layer interaction.In addi-tion,the geometric parameter above can affect pressure distribution around the plug,and the Mach number distri-bution on the core nozzle exit plane.As a result,the thrust of the core cowl,the plug,and the core nozzle is af-fected significantly.The fan nozzle is supercritical and the core nozzle is subcritical at cruise condition,so the geometric parameters of the core nozzle will affect the mass flow rate and thrust of the core nozzle but the perfor-mance of the fan nozzle.The variation of the core nozzle mass flow rate could change the mass flow rate of the en-gine and affect the ram drag,additional drag and cowl drag further.

关 键 词：涡扇发动机 内涵喷管 外涵喷管 超大涵道比短舱 气动性能 

分 类 号：V231.1[航空宇航科学与技术—航空宇航推进理论与工程]