考虑污染物排放的开式转子发动机总体性能建模及分析研究

Modeling and performance analysis of open rotor engine considering pollutant emissions

关键词:  开式转子发动机  对转桨扇  发动机建模  污染物排放  性能分析

Key words:  Open rotor engine  Contra-rotating propeller  Engine modeling  Pollutant emissions  Performance analysis

摘要:

开式转子发动机兼具涡桨发动机高推进效率和涡扇发动机高飞行速度的特点，是未来民用单通道客机理想动力装置之一。为了掌握开式转子发动机的性能变化规律，明确开式转子发动机相比于常规大涵道比涡扇发动机节油和降低污染物排放的优势，本文基于螺旋桨相似理论和动量理论，建立了考虑前后排桨扇相互影响的对转桨扇模型；与双轴燃气发生器进行匹配，建立了三轴齿轮传动开式转子发动机模型；同时建立了发动机污染物排放计算模型；对同技术水平的开式转子发动机和大涵道比涡扇发动机进行了性能对比。结果表明：所建立的对转桨扇模型与实验结果误差较小，最大误差不超过3%。飞行马赫数增大，桨扇功率系数增大，推力系数减小，耗油率增大；飞行高度增加，桨扇功率系数和推力系数均增大，耗油率呈减小的趋势。相比于同技术水平的大涵道比涡扇发动机，开式转子发动机在典型工况下的耗油率降低9%以上。在飞机起飞着陆循环内，开式转子发动机的UHC，CO和NO_x三种污染物排放指数相比于大涵道比涡扇发动机降低10%以上，表明开式转子发动机可有效降低航空污染物的排放。

Abstract:

The open rotor engine has the characteristics of high propulsion efficiency of turboprop engine and high flight speed of turbofan engine， and is one of the ideal power devices for future civil single-aisle passenger aircraft. In order to grasp the performance variation of the open rotor engine， and to clarify the advantages of the open rotor engine compared with the high bypass ratio turbofan engine in fuel saving and pollutant emissions reducing， this paper established a contra-rotating propeller model based on the propeller similarity theory and momentum theory， which considers the interaction between the front and rear propeller. Matching with the dual-shaft gas generator， a three-shaft gear drive open rotor engine model was established. An engine pollutant emissions calculation model was established. The performance of the open rotor engine and high bypass ratio turbofan engine were compared finally at the same technical level. The results show that the error between the established contra-rotating propeller model and experimental results is small， and the maximum error does not exceed 3%. When the flight Mach number increases， the contra-rotating propeller power coefficient increases， the thrust coefficient decreases， and the fuel consumption rate increases. When the flight altitude increases， the contra-rotating propeller power coefficient and thrust coefficient both increase， and the fuel consumption rate tends to decrease. Compared with the high bypass ratio turbofan engine of the same technical level， the fuel consumption of the open rotor engine under typical operating conditions is greatly reduced by more than 9%. In the landing-takeoff cycle， the three pollutant emission indices of UHC， CO and NO_x of the open rotor engine are reduced by more than 10% compared with the high bypass ratio turbofan engine， indicating that the open rotor engine can effectively reduce the emission of aviation pollutants.