Axial Turbine Performance Estimation During Dynamic Operations

Abstract

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.

Performance of a microjet using component map scaling

“…Dr Joachim Kurzke is the developer, designer and inventor of GasTurb. The main purpose of the software is to perform on-design and off-design analyzes corresponding to specific parameters of gas turbines that are used both in aircraft propulsion systems and as a propulsion element in combined power cycles (Kurzke, 2007; Kuz’michev et al , 2017; Hashmi et al , 2020; Nicoara et al , 2020). GSP developed by the National Aerospace Laboratory and commercially launched is a comprehensive computer-aided engineering software that offers aero-thermodynamic relationships, steady-state characteristics and dimensionless modeling in the simulation, adaptation, and operation processes of various gas turbine engines and components (Altarazi et al , 2020; Visser, 2020).…”