12th European Conference on Turbomachinery Fluid dynamics & Thermodynamics
Transient blade loading caused by the interaction of different blade rows is one limiting factor of turbo machinery blading lifetime especially when it leads to forced response. In order to reduce the calculation effort associated with 3D computational fluid dynamics (CFD), modern transient blade row methods such as the time transformation (TT) method are used. This paper investigates the capability of the TT method to predict these phenom-ena by the example of the last two stages of a shrouded 4-stage air-turbine. Numerical simulations are performed using the commercial flow solver ANSYS CFX. In a detailed time step and grid influence study the sufficient resolution of all predominant flow features is ensured. The results of the TT method are then compared to a reference (REF) calcula-tion using direct periodic treatment with focus on the force signals, frequency spectra and the distribution of the first harmonic amplitude of pressure signal along the blade surface.