基于直二元喷管形面尺寸的涡扇发动机参数优化设计研究

Optimization Design of Turbofan Engine Parameters Based on Straight Two-Dimensional Nozzle Profile

关键词:  涡扇发动机  设计参数  直二元喷管  序列二次规划  多目标优化

Key words:  Turbofan engine  Design parameters  Straight two-dimensional nozzle  Sequential quadratic programming  Multi-objective optimization

摘要:

为了在设计阶段提升带直二元喷管涡扇发动机的总体性能，开展了基于直二元喷管形面尺寸的涡扇发动机参数优化的研究。首先，建立了带直二元喷管的涡扇发动机模型，提出了发动机正后向排气系统红外辐射特征的计算方法，分析了直二元喷管尺寸对发动机性能参数的影响；其次，提出了基于序列二次规划算法的设计参数多目标优化方法，优化的目标包括高单位推力、低油耗和低红外辐射强度；最后，基于以上模型，利用序列二次规划算法对在设计点非加力情况下的涡扇发动机设计参数进行多目标优化。仿真结果表明：在设计点上，相较于不带直二元喷管的涡扇发动机，带直二元喷管的涡扇发动机具有更好的红外性能，并且通过算法优化后，带直二元喷管的涡扇发动机具有更好的性能参数。

Abstract:

In order to improve the overall performance of turbofan engines with straight two-dimensional nozzle at design stage， optimization design of turbofan engine parameters based on straight two-dimensional nozzle profile dimensions was carried out. Firstly， a turbofan engine model with straight two-dimensional nozzle was established， and the infrared radiation characteristic of the forward backward exhaust system of the engine was calculated. The influence of the dimension sizes of the straight two-dimensional nozzle on the engine performance parameters was analyzed. Secondly， a multi-objective optimization method of design parameters based on sequential quadratic programming algorithm was proposed. The optimized objectives include high specific thrust， low fuel consumption and low infrared radiation. Finally， based on the above model， the sequential quadratic programming algorithm was used to carry out the multi-objective optimization of the design parameters of turbofan engine without afterburning at design point. The simulation results show that， compared with the turbofan engine without straight two-dimensional nozzle， the turbofan engine with straight two-dimensional nozzle has better infrared performance at design point， and the turbofan engine with straight two-dimensional nozzle has better performance parameters after optimization by the algorithm.