This paper gives an overview of the capabilities for unsteady flow simulations of low pressure turbine\r\ncascades by using modern transition models. The numerical results are compared to the experimental test\r\ncase T106D-EIZ measured at the high-speed test facility of the University of German Armed Forces Munich.\r\nThe T106D-EIZ is an ultra-high-lift profile with a pitch to chord ratio of 1.05 and therefore has a big\r\nseparation bubble even at a high Reynolds number. Many transition models are calibrated with the\r\nmoderately loaded (pitch to chord ratio of 0.799) T106A test case, which makes the T106D-EIZ a very\r\ndemanding test case for the prediction capabilities of modern transition models using the Unsteady Reynolds\r\nAveraged Navier Stokes (URANS) equations. A special focus lies on the comparison between the different\r\ncorrelations proposed by Menter and Malan for the  Ret local quantities transport transition model. Both\r\ncorrelations are compared to the experimental results and results obtained by a transition model relying on\r\nintegrated boundary layer parameters. In a first step the results of the steady test case situation are\r\nanalysed to calibrate the correct axial velocity density ratio for the quasi 3D calculation. After that time\r\naveraged isentropic Mach number distributions, obtained by unsteady flow simulations, are analysed to\r\nhighlight the differences between the different transition models. This also includes comparisons of time\r\nspace distributions of the quasi wall shear stress rate with computed shear stress rate. Especially in that\r\nanalysis larger differences were found, which could not be explained using the conventional time space\r\ndiagram. Therefore, a 3D time space diagram was used to highlight the differences within the local quantities\r\nused by the  Ret transition model. This analysis lead to a proposal in which way this model could be\r\nimproved to gain better prediction capabilities.    «

This paper gives an overview of the capabilities for unsteady flow simulations of low pressure turbine\r\ncascades by using modern transition models. The numerical results are compared to the experimental test\r\ncase T106D-EIZ measured at the high-speed test facility of the University of German Armed Forces Munich.\r\nThe T106D-EIZ is an ultra-high-lift profile with a pitch to chord ratio of 1.05 and therefore has a big\r\nseparation bubble even at a high Reynolds number. Many transition models...    »