航空发动机燃烧室数字孪生体系关键技术

Key technology of digital twin system for aero-engine combustors

通过曲线坐标系浸没边界方法(IBM),在设计阶段可以实现对真实航空发动机燃烧室的高保真虚实映射,保留全部几何结构信息。在IBM方法基础上,采用大涡模拟(LES)结合概率密度函数输运方程湍流燃烧模型(TPDF),对双旋流燃烧室、某单头部直流燃烧室以及某折流燃烧室1/10模型进行真实结构仿真,测试数字孪生体系关键技术的有效性。对比预测结果和实验结果,双旋流燃烧室的旋流器出口附近轴向、径向、切向速度平均误差分别为15.7%、23.8%、15.0%;非稳态解析了真实直流燃烧室与折流燃烧室的详细湍流燃烧场,出口温度分布的平均相对误差分别为11.66%和17.95%。因此基于虚实映射得到的燃烧室数字孪生体系具有一定的有效性,该方法具有潜在的工程应用前景。

The curvilinear coordinate system’s immersion boundary method(IBM)can be used to realize high-fidelity virtual-real mapping of the real aero-engine combustor in the design stage,and retain all the geometric structure information.Based on the IBM method,large eddy simulation(LES)combined with transported probability density functional turbulent combustion model(TPDF)was used to simulate the real structure of a double-swirler combustor,a single-head model of a throughflow combustor and 1/10 model of a slinger combustor,and test the effectiveness of key technologies of the digital twin system.Compared with the prediction and experiment results,the average errors of axial,radial and tangential velocities near the outlet of the swirler of the double-swirler combustor were 15.7%,23.8%and 15.0%,respectively.The detailed turbulent combustion fields of the single-head model of a throughflow combustor and the slinger combustor were analyzed under the unsteady state,and the average relative errors of the outlet temperature distribution were 11.66%and 17.95%,respectively.Therefore,the combustor’s digital twin system obtained based on virtual real mapping has certain effectiveness,and the proposed method has potential engineering application prospects.