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1

Parallelized numerical code for derivation of heat transfer coefficient from experimental data

Telega J., Doerffer P., Szwaba R., Kaczyński P.

TASK Quarterly : scientific bulletin of Academic Computer Centre in Gdansk

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2015

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Vol. 19, No 2

197--205

EN

An application of parallel computation capabilities in the MATLAB language for the analysis of experimental data concerning the heat transfer coefficient on ribbed walls is presented in this paper. A description of the experimental study, mathematical model and numerical implementation is also given. The obtained results of measurements and calculations shown here clearly indicate the influence of ribbed walls on the heat transfer coefficient distribution in an internal, subsonic flow.

2

Influence of air cooling and air-jet vortex generator on flow structure in turbine passage

Szwaba R., Flaszyński P., Szumski J. A., Doerffer P.

TASK Quarterly : scientific bulletin of Academic Computer Centre in Gdansk

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2015

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Vol. 19, No 2

153--166

EN

The paper concerns the experimental investigations and numerical simulations of a high loaded model of a turbine blade. An increase in the blade load leads to enlargement of a local supersonic zone terminated by a shock wave on the suction side. The Mach number upstream of the shock reaches up to 1.6. The interaction of the shock wave with a boundary layer at such a high Mach number leads to a strong separation. Streamwise vortices generated by air-jets were used for the interaction control. The work presents the experimental and numerical results of the application of an air-jets vortex generator on the suction side of cooled turbine blades. Very interesting results were obtained in the context of the air cooling and air-jet vortex generator influence on the flow structure in the turbine passage.

3

Aerodynamic anhancement in inner channel of turbine blade

Kaczyński P., Szwaba R., Puchowski B., Doerffer P., Flaszyński P.

TASK Quarterly : scientific bulletin of Academic Computer Centre in Gdansk

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2015

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Vol. 19, No 2

101--110

EN

This paper presents the numerical and experimental study of the flow structure in a radial cooling passage model of a gas turbine blade. The investigations focus on the flow aerodynamics in the channel, which is an accurate representation of the configuration used in aero engines. The flow structure and pressure drop were measured by classical measurement techniques. The stagnation pressure and velocity measurements in a channel outlet plane were performed. The investigations concerning the flow field and heat transfer used in the design of radial cooling passages are often developed from simplified models. It is important to note that real engine passages do not have perfect rectangular cross sections, but include corner fillets, ribs with fillet radii and special orientation. Therefore, this work provides detailed fluid flow data for a model of radial cooling geometry which possesses very realistic features. The main purpose of these investigations was to study different channel configurations and their influence on the flow structure and pressure losses in a radial cooling passage of a gas turbine blade.

4

Numerical simulations of a conceptual blade cooling with a working medium

Rogoziński K., Nowak G.

Computer Assisted Methods in Engineering and Science

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2015

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Vol. 22, no. 3

267--278

EN

The development of steam power units aims to increase the working steam parameters as they are the main factors that determine the efficiency of energy conversion. Most state of the art units are designed for supercritical steam parameters. However, the temperature level of steam feeding the turbine is limited by thermal strength of the material used to make the machine components. In this situation, using nickel alloys or cooling the elements exposed to the impact of high temperatures could be the appropriate solution. The former is rather expensive and the latter – technically difficult. The cooling option would require that the cooled element should be fed by a steam with a very high pressure and with a lower temperature than the temperature in the machine flow system. This paper presents the concept of using working steam as the cooling medium after it is expanded in a convergent-divergent nozzle. In such a case, the cooling system is very simple and the performed simulations indicate, for example, that the turbine blades may be cooled in this way.

5

Numerical simulation of thermally loaded aircraft engine turbine blade covered with thermal barrier coating - TBC

Łazarczyk M., Domański R.

Journal of KONES

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2012

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Vol. 19, No. 3

271-277

EN

The objective of this thesis is to present the impact of the turbine blade cooling on blade material temperature as well as to assess advantages and disadvantages of applied cooling method (TBC coating combined with internal cooling). To calculate the conjugated heat transfer analysis generating 3d model and mesh of the blade and its cooling was required. Model mesh was covered with boundary layer in order to properly simulate conditions near the blade walls and obtain accurate results. Calculated blade was put in the canal simulating hot combustion gasses flow. Geometry of model described above was created using Unigraphics NX5 program based on drawings obtained from available literature, and data acquired from the Internet. The discretization was done in commercial pre--processor GAMBITŽ. Conjugated heat transfer analysis was conducted in program FLUENTŽ for two different cases, where the TBC material properties were changed. The goal of this thesis was to obtain temperature fields and distribution in the turbine blade airfoil and to evaluate if applied cooling is sufficient to cool down this thermally loaded part of the engine. Calculated results show that proposed blade heat protection with TBC and internal cooling canal is insufficient during steady state condition, especially on the blade leading and trailing edge. In these two locations, the TBC coating is overheated, and the high temperature level of blade material is unacceptable for materials used in jet engine turbine industry.

6

Computational fluid dynamics methods in turbomachinery

Chmielniak T. J.

TASK Quarterly : scientific bulletin of Academic Computer Centre in Gdansk

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1998

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Vol. 2, No 2

205-213

EN

This paper aims to present a general view of flow problems in turbomachinery and the current levels of numerical methods for solving these problems. The flow models used for modelling phenomena in blade cascades are presented. Models of turbulence are discussed. A variety of examples of turbomachinery problems, such as steady, unsteady, multiphase and multicomponent flows, and also blade cooling are described. The actual research fields of computational fluid mechanics are presented.