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The paper deals with numerical modelling of carbon dioxide capture by amine solvent from flue gases in post-combustion technology. A complex flow system including a countercurrent two-phase flow in a porous region, chemical reaction and heat transfer is considered to resolve CO 2 absorption. In order to approach the hydrodynamics of the process a two-fluid Eulerian model was applied. At the present stage of model development only the first part of the cycle, i.e. CO 2 absorption was included. A series of parametric simulations has shown that carbon dioxide capture efficiency is mostly influenced by the ratio of liquid (aqueous amine solution) to gas (flue gases) mass fluxes. Good consistency of numerical results with experimental data acquired at a small-scale laboratory CO 2 capture installation (at the Institute for Chemical Processing of Coal, Zabrze, Poland) has proved the reliability of the model.

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This paper presents the results of tests and validations of the γ-Reθ model proposed by Menter et al. (2006, “A Correlation-Based Transition Model Using Local Variables—Part I: Model Formation,” ASME J. Turbomach., 128, pp. 413–422), which was extended by in-house correlations for onset location and transition length. The tests performed were based on experimental data from the flat plate test cases available at the ERCOFTAC database as well as on experimental data from the turbine blade profile investigated at Czestochowa University of Technology. Further on, the model was applied for unsteady calculations of the blade profile test case, where chosen inlet conditions (turbulent intensity and wake parameters) were applied. For the selected case, numerical results were compared not only with the experimental data but also with the results obtained with other transition models. It was shown that the applied model was able to reproduce some essential flow features related to the bypass and wake-induced transition, and the simulations revealed good agreement with the experimental results in terms of localization and extent of wake-induced transition.

The paper presents an experimental and numerical analysis of the interaction between wakes and boundary layers on aerodynamic blade profiles. The experiment revealed that incoming wakes interact with boundary layers and cause the significant increase of velocity fluctuations in the boundary layer and in consequence shift the transition zone towards the leading edge. The full time evolution of periodic wake induced transition was reproduced from measurements. The numerical simulation of the flow around the blade profile has been performed with the use of the adaptive grid viscous flow unNEWT PUIM solver with a prescribed unsteady intermittency method (PUIM) developed at Cambridge University, UK. The results obtained give evidence that the turbulence transported within the wake is mainly responsible for the transition process. The applied CFD solver was able to reproduce some essential flow features related to the bypass and wake-induced transitions and the simulations reveal good agreement with the experimental results in terms of localisation and extent of wake-induced transition.