摘要
为评估分开排气大涵道比涡扇发动机高空模拟试验的排气特性,采用数值仿真方法,对分开排气发动机高空模拟试验时配备的排气扩压器的结构进行分析。主要从发动机尾锥与排气扩压器入口距离、排气扩压器结构尺寸、舱内压力模拟偏差及次流四方面影响进行排气特性计算,并以发动机设计推力进行检验。结果表明:该发动机进行高空模拟试验时,排气扩压器直径应不小于3.5 m,排气扩压器直段长度不小于9.0 m,发动机尾锥与排气扩压器入口距离以0.85倍扩压器直段直径为宜;发动机飞行包线的巡航点和左边界点的推力偏差,均随模拟舱压偏差绝对值的增大而增大,但巡航点推力变化斜率较大。
In order to evaluate the exhaust characteristic of the high ,altitude simulation test for the separate exhaust turbofan engine, the numerical simulation method was used to analyze the geometry of exhaust dif-fusers which were employed in a separate exhaust engine altitude simulation test. The influence of the dis-tance between engine caudal and the exhaust diffuser main entrance, the exhaust diffuser size, the height （atmosphere pressure） analog deviation, as well as the secondary flow were fully investigated and validated on design thrust of the turbofan engine. The results of these calculations show that in this separate exhaust high altitude simulation test, the diameter of the exhaust diffuser should be not less than 3.5m;the length of the exhaust diffuser straight section is not less than 9.0m;the appropriate distance from engine caudal to the exhaust diffuser main entrance is about 0.85 times of exhaust diffuser straight section;the engine thrust off-set of the cruise and a left boundary point at the flight envelope increases when the atmosphere pressure an-alog deviation grows;but the increase rate of the cruise point is larger.
出处
《燃气涡轮试验与研究》
北大核心
2015年第2期7-13,共7页
Gas Turbine Experiment and Research
关键词
航空发动机
高空模拟试车台
排气扩压器
涵道比
推力
数值仿真
aero-engine
altitude simulation test facility
exhaust diffuser
bypass ratio
thrust
numerical simulation
