大涵道比涡扇发动机风扇转子叶片优化

采用掠形设计技术对一台大涵道比涡扇发动机的风扇转子叶片进行了三维优化.通过三维定常Navier-Stokes（N-S）方程计算，分析了叶片尖部及根部掠形设计参数对风扇转子性能的影响.结果表明，叶片尖部前掠和根部后掠都能增加风扇转子的堵点流量，扩大其稳定工作范围.采用叶片尖部前掠和根部后掠的组合方案优化了叶片.单转子计算结果表明，优化后叶片的堵点流量增加约2%，设计流量点总压比和等熵效率分别增加5%和2%；风扇/增压级整机内外涵联算结果表明，优化后在起飞、巡航和爬升转速下，外涵的稳定工作范围都明显增加，巡航转速下，堵点流量增加约2.3%，失速点流量减小约5.2%，设计流量点的外涵总压比和等熵效率分别增加2%和0.8%，优化后内涵特性没有明显变化. 

Optimization of fan rotor blade in high bypass ratio turbofan engine

By using sweep design technique, the fan rotor blade of a high bypass ratio turbofan engine was optimized in three-dimensional configuration. The influence of the sweep design parameters at blade tip and hub on the performance of the fan rotor were studied by solving three-dimensional steady Navier-Stokes (N-S) equations. The results show that both forward sweep at blade tip and backward sweep at blade hub can enhance the performance of the fan rotor, increase its chock point mass flow and enlarge its stable working range. The blade was optimized by the combined choice of forward sweep at blade tip and backward sweep at blade hub. The calculation result of the single rotor shows that the total pressure ratio and isoentropic efficiency at design mass flow point are increased 5% and 2%, respectively, and the chock point mass flow is increased about 2%. The core and bypass of fan/compressor combined calculation results show that the stable working range of the bypass is enlarged at different rotating speeds of take off, cruise and climbing state after optimization. The mass flow is increased about 2.3% at the chock point, and decreased about 5.2% at stall point at rotating speed of cruise. The total pressure ratio and isoentropic efficiency of the bypass are increased about 2% and 0.8% at design mass flow point, while the performance of the core does not change significantly after optimization.