旋转爆震燃烧向心涡轮组合流场数值研究  

Numerical study of combined flow field of rotating detonation coupling with radial inflow turbine

作　　者：林君宁 林志勇 张成名 LIN Junning;LIN Zhiyong;ZHANG Chengming(School of Aeronautics and Astronautics,Sun Yat-sen University,Shenzhen 518107,China)

机构地区：[1]中山大学航空航天学院,广东深圳518107

出　　处：《推进技术》2024年第12期170-180,共11页Journal of Propulsion Technology

摘　　要：爆震燃烧自增压特性可以有效提高涡轮的轮轴功输出。为探究旋转爆震燃烧应用于向心涡轮的可行性并分析爆震燃烧与涡轮相互作用机理,本文建立了旋转爆震向心涡轮三维分析模型,研究了不同转速和流量下旋转爆震传播及涡轮流场特性的变化规律。数值计算结果表明,在向心涡轮高速旋转时环形爆震燃烧室中可以获得稳定自持的爆震波。旋转爆震诱导的斜激波会显著改变涡轮流道内的气流方向,并在叶片局部产生分离涡和超声速流动;斜激波经过涡轮作用后压强峰值显著降低,振幅下降了60%;爆震涡轮组合工作能够增大向心涡轮的压比和温降,从而提高涡轮输出功和输出转矩,其峰值输出功在转速与理论最佳速度比为0.75时达到最大,比相同工况下的等压燃烧涡轮输出功高30%~40%,其最大输出转矩为12 N·m;而爆震模态下涡轮出口的超声速流动增大了激波损失,涡轮效率下降了20%。在0.36~0.40 kg/s流量内,爆震模态下涡轮落压比和总温随流量变化较小,涡轮的输出转矩和流量成正比;但进一步提高流量会造成流道拥塞,影响爆震波的稳定传播。The characteristics of self-pressurization of rotating detonation combustion can effectively im⁃prove the power output of turbines.In order to explore the feasibility of applying rotating detonation combustion to radial inflow turbine and analyze the interaction mechanism of their coupling operation,a three-dimensional analysis model which combines rotating detonation combustion and radial inflow turbine is constructed to study the propagation of rotational detonation waves and the changes of aerodynamic characteristics of the internal flow of turbines at different rotating speed and flow rate condition.The results show that stable self-sustaining detona⁃tion wave can be obtained in the annular detonation chamber when radial inflow turbine is rotating at high speed.The oblique shock wave induced by rotating detonation will significantly change the direction of the flow in the turbine channel,and generate separation vortex and supersonic flow in the blade.The amplitude of pressure oscil⁃lation decreased by 60%after turbine.The coupling operation can increase the pressure ratio and temperature drop of the radial turbine,thereby improving turbine’s output power and torque.The peak output work reaches its maximum when the speed ratio to theoretical optimal speed is 0.75,which is 30%~40%higher than the output power of constant pressure combustion turbines under the same working condition,and its maximum output torque is 12 N·m.In detonation mode,supersonic flow at turbine outlet increases shock loss and turbine efficien⁃cy decreases by 20%.In the flow rate range of 0.36~0.40 kg/s,the drop pressure ratio and total temperature of the turbine under detonation mode change little with the flow rate,and the output torque of the turbine is proportional to the flow rate.However,the further increase of flow rate will cause the flow channel congestion and affect the stable propagation of detonation wave.

关 键 词：旋转爆震 斜激波 向心涡轮 涡轮叶片 涡轮输出功 涡轮效率 涡轮转矩 

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]