During service, a turbine engine undergoes frequently dynamic operations. Because of the changes in mass flow, temperature, pressure, as well as the different reaction of the components of turbine to these changes, the turbine performances may vary significantly. It is critical to understand and quantify these variations to design and integrate the turbine to the engine. This paper presents a study of the performances and the variation of the performances for an axial gas turbine across its operating envelope. Numerical simulations are used to describe the flow across the turbine and to estimate the turbine maps. Using theoretical charts for typical turbine thermal expansion, the variation of tip clearance across the working line is approximated. Because of the changes of the tip clearance, using a single geometry may not supply relevant information during real dynamic operations. In order to eliminate these additional errors in the numerical study, a number of turbines maps are recalculated for different tip clearances, respectively to engine regimes. With the resulting data, the working line is recalculated across multiple maps. The comparison between the two working lines is presented as well as the study of performance variation of the turbine across the operation envelope and the influence of tip clearance at different regimes.

中文翻译：

---

动态运行期间的轴向涡轮机性能估计

在使用期间，涡轮发动机经常经历动态操作。由于质量流量、温度、压力的变化以及汽轮机部件对这些变化的不同反应，汽轮机性能可能会有很大差异。理解和量化这些变化对于设计涡轮机并将其集成到发动机中至关重要。本文研究了轴流式燃气轮机在其运行范围内的性能和性能变化。数值模拟用于描述穿过涡轮机的流量并估计涡轮机图。使用典型涡轮机热膨胀的理论图表，可以近似计算工作线上叶尖间隙的变化。由于尖端间隙的变化，在实际动态操作期间，使用单个几何图形可能无法提供相关信息。为了消除数值研究中的这些额外误差，针对不同的叶尖间隙，分别针对发动机状态重新计算了多个涡轮图。使用结果数据，跨多个地图重新计算工作线。介绍了两条工作线之间的比较，并研究了涡轮机在整个运行范围内的性能变化以及不同状态下叶尖间隙的影响。