... Abstract Flow transition is a common phenomenon in fluid dynamics, widely observed, particularly in scientific and technological fields such as turbomachine. However, accurately measuring and predicting flow transition poses a significant challenge due to its inherent complexity, and acquiring...

... to a higher-pressure condition at the blade exit. The ‘separation bubble’ thus formed could, in many cases, trigger flow transition from laminar to turbulent conditions on reattachment further downstream of the point of separation. Since blade profile losses depend on the transition location, the modification...

..., and blade loads. DLR’s CFD solver TRACE is used for the numerical simulations with a rotation-corrected k-ω turbulence model, Low-Mach preconditioning, and the γRe Θ transition model. A robust method for evaluating boundary layer parameters is introduced, based on which representative reference airfoils...

... at off-design conditions. For the low-pressure turbine, the low Reynolds number off-design conditions become particularly of concern for increased loss generation. This current paper focuses on the validation of transition predictions for two low-pressure turbine airfoils using linear turbine cascade...

... Abstract This study analyzes the influence of Reynolds number on the turbulence anisotropy behavior for the transitional flow over the MTU-T161 linear low-pressure turbine (LPT) cascade. Two operating points at Reynolds number Re = 90,000 and Re = 200,000, both at an isentropic exit Mach number...

... Abstract All modern gas turbines, from a small business jet to a large civil engine, make use of film cooling within the HP turbine. Transition on the blade surfaces has a large impact on blade heat transfer and profile loss. Many studies have considered the role of freestream turbulence...

...Proceedings of ASME Turbo Expo 2024 Turbomachinery Technical Conference and Exposition GT2024 June 24-28, 2024, London, United Kingdom GT2024-124283 INFLUENCE OF VARYING FREESTREAM TURBULENCE ON FLOW TRANSITION OVER DISTRIBUTED SURFACE ROUGHNESS Ishita Jain, Shubham Katiyar and S. Sarkar...

... Abstract In this first paper of the two-part series, we analyze the predictive quality of transitional Delayed Detached-Eddy Simulation (DDES) for the transonic TU Darmstadt (TUDa) compressor stage. Initially, we validate the DDES in a translational configuration of the compressor at reduced...

... aerofoil at all where the transition is governed by inviscid instability. Leadingedge modification with herringbone riblets induced higher turbulence in proximity to the wall, resulting in an earlier transition of the shear layer and a reduction in bubble length by 36-20% for = 0 5 along with a change...

... Abstract The present paper focuses on the adverse effects caused by transitional shock wave boundary layer interaction (SBLI) on a highly loaded variable stator vane (VSV) at altitude. The VSV section under investigation is representative of business jet applications. A new design solution...

... the impact on flow physics of interest, such as boundary layer evolution, laminar-to-turbulent transition, and wake shedding. The numerical results show that as Reynolds number is increased, a critical value is reached where the shedding behavior of trailing edge vortices changes, resulting in a jump in wake...

... Abstract The flow over the linear low-pressure turbine cascade MTU-T161 at Re = 90,000 is analyzed using Delayed Detached Eddy Simulations (DDES). At this operating point, the low Reynolds number and the high loading of the blade result in a separation bubble and a separation-induced transition...

... the wake loss region of a linear cascade with sparse experimental data. turbulence transition physics-informed neural networks low-pressure turbine closure modelling machine learning Proceedings of ASME Turbo Expo 2023 Turbomachinery Technical Conference and Exposition GT2023 June 26-30, 2023...

...Proceedings of ASME Turbo Expo 2023 Turbomachinery Technical Conference and Exposition GT2023 June 26-30, 2023, Boston, Massachusetts, USA GT2023-103382 THE INFLUENCE OF SURFACE ROUGHNESS ON FLOW TRANSITION BY WELL-RESOLVED LARGE EDDY SIMULATIONS Ishita Jain, Issam Wajih and S. Sarkar* Department...

... Abstract This paper describes the effects of pressure gradients on the transition of a laminar separation bubble (LSB) formed over the flat plate. The measurements were performed using electronically scanned pressure (ESP) and hot-wire anemometer. The different adverse pressure gradients (APG...

... Abstract This work presents an experimental and numerical investigation on the laminar-turbulent transition and secondary flow structures in a Turbine Rear Structure (TRS). The study was executed at engine representative Reynolds number and inlet conditions at three different turbine load cases...

... inflow angle of 38.3°. The objective of the present study is to assess how this leading-edge bubble influences the transition and development of boundary layer on the suction surface before the mid-chord. It appears that the separation at leading-edge suddenly enhances the perturbation levels exciting...

.... With a uniform inlet, the laminar boundary layer separates near the leading edge, undergoes transition due to amplification of the disturbances, becomes turbulent and finally reattaches forming a bubble. In the presence of oncoming wakes, the characteristics of the separated layer have changed and the impinging...

... This paper presents an effort to model separation-induced transition on a flat plate with a semi-circular leading edge, by using two advanced turbulence models, the three equation non-linear model k-ε-A 2 of Craft et al. [16] and the Reynolds-stress model of Craft [13]. The mechanism...

... 23 02 2010 A rectangular bar which just likes a forward-backward facing step was designed to passive control of the Low-Pressure Turbine (LPT) PakB cascade suction surface separation. Large-eddy simulation (LES) was adopted to analyze the separated-transition flows for the PakB cascade...