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1

Influence of mesh density on 2D viscous flutter in a turbomachinery cascade

Pająk A., Soliński M., Rządkowski R.

Zeszyty Naukowe. Cieplne Maszyny Przepływowe - Turbomachinery / Politechnika Łódzka

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2011

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nr 140

169-178

EN

In this study numerical simulations of 2D viscous flutter were performed and compared with available experimental results for various mesh densities and flow parameters. Calculations were carried out for the bending oscillations of an Eleventh Standard Configuration cascade. ANSYS CFX code was used for the SST, SA and k-ω turbulence model calculations.

2

Dynamic analysis of first stage compressor bladed disk of an aircraft engine

Rzadkowski R., Drewczyński M., Soliński M., Maurin A., Maciejewska A., Szczepanik R.

Problemy Eksploatacji

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2011

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nr 1

157-165

EN

There have been a number of SO-3 first stage compressor blade failures. An experiment was carried out on a first stage rotor blade in the compressor of an SO-3 engine at the Air Force Institute of Technology in Warsaw. The natural frequencies of rotor blades were measured. Next, the tip-timing measurement of rotor blade was done in an engine working at various speeds. Various operation conditions were assumed, such as the presence of a foreign object in the engine inlet. Structure and flow calculations were carried out to compare the experimental results. An FEM was used to calculate the natural frequencies of a mistuned bladed disk. The FLUENT code was used to calculate the unsteady forces acting on rotor blades. The mistuned bladed disk was forced to vibrate when rotating at 15000 rpm.

PL

Odnotowano wiele uszkodzeń łopatek wirnikowych pierwszego stopnia sprężarki silnika SO-3. W Instytucie Technicznym Wojsk Lotniczych w Warszawie przeprowadzono cykl eksperymentów na łopatkach wirnikowych pierwszego stopnia sprężarki silnika SO-3. Zmierzono częstotliwości drgań własnych łopatek wirnikowych. Wykonano pomiary przemieszczeń łopatek wirnikowych metodą tip-timing dla różnych prędkości obrotowych wirnika. W trakcie badań uwzględniono także obecność obcego ciała we wlocie silnika. Przeprowadzono obliczenia numeryczne przepływu w pierwszym stopniu sprężarki i drgającej ułopatkowanej tarczy, w celu porównania z wynikami otrzymanymi z badań eksperymentalnych. Metoda elementów skończonych zastosowana została do analizy drgań wymuszonych ułopatkowanej tarczy z łopatkami różniącymi się wymiarami geometrycznymi, dla nominalnej prędkości obrotowej n=15 000 obr./min. Program FLUENT zastosowany został do obliczenia niestacjonarnych sił działających na łopatki wirnikowe.

3

Influence of wind energy on the environment

Soliński I., Soliński M.

Czasopismo Techniczne. Chemia

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2008

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R. 105, z. 2-Ch

77-83

EN

In the 1970s, oil shortages pushed the development of alternative energy sources. In the 1990s, the push came from a renewed concern for the environment in response to scientific studies indicating potential changes to the global climate if the use of fossil fuels continued to increase. Wind energy is an economical power resource in many areas of the country. Wind is a clean fuel, wind farms produce no air or water pollution because no fuel is burned. Growing concern about emissions from fossil fuel generation, increased government support, and higher costs for fossil fuels have helped wind power capacity grow substantially over the last 10 years. The state and perspectives of the wind energy development in Poland, Europe and the world is shown in the paper.

PL

Kryzys energetyczny lat siedemdziesiątych przyspieszył rozwój alternatywnych źródeł energii. W latach 90. nastąpił rozwój tych źródeł energii wywołany zaobserwowanym globalnym ociepleniem klimatu, którego przyczyną jest wykorzystanie konwencjonalnych źródeł energii. W artykule przedstawiono stan i perspektywy rozwoju energetyki wiatrowej w świecie, Europie i Polsce oraz wpływ na środowisko przyrodnicze. Wskazano, że energetyka wiatrowa w minimalnym stopniu negatywnie wpływa na środowisko, wywierając duży wpływ na zmniejszenie emisji szkodliwych substancji.

4

Unsteady Forces Acting on Blades and the Shaft in the Last Stage of Steam Turbine with Exhaust Hood

Rządkowski R., Soliński M., Kwapisz L., Gnesin V.

Zeszyty Naukowe. Cieplne Maszyny Przepływowe - Turbomachinery / Politechnika Łódzka

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2005

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nr 128, vol. 2

471-478

EN

The aerodynamic unsteady forces acting on the rotor blades and the shaft in the last stage of turbine 13K215 were calculated. A numerical simulation of a 3D transonic ideal gas flow through turbomachinery blade rows moving relative to one another is presented, with a non-uniform pressure distribution of steam behind the rotor blades. In order to find the pressure distribution, numerical calculations were done for unsteady flow through the stage with the exhaust hood using the program FLUENT. The unsteady forces of the rotor blades were calculated. The natural frequencies of the bladed disc were compared with the frequencies of the flow excitations. Next, the unsteady forces acting on the shaft were calculated, taking the mistuning of the blades into consideration.

5

High and low frequency excitations of the last stage rotor blades and shaft of the steam turbine 13K215

Rządkowski R., Gnesin V., Soliński M.

Transactions of the Institute of Fluid-Flow Machinery

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2003

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nr 114

123-132

EN

A three-dimensional numerical analysis for aerodynamic unsteady forces of the last stage steam turbine 13K215 rotor blades and total unsteady forces acting on the shaft from considered stage, have been presented. The numerical calculations were performed for different pressure distribution behind the rotor blades in circumferential direction (p2=6000, 7500, 9000, 7500 Pa). The analysis of the 3D transonic flow of an ideal gas through turbomachinery blade rows moving relatively one to another without takong into account the blades oscillations is presented. An ideal gas flow through the mutually moving stator and rotor blades with periodicity on the whole annulus is describrd by the unsteady Euler conservation equations, which are integrated using the explicit monotonous finite-volume difference scheme of Godunov-Kolgan and moving hybrid H-H grid. The algorithm proposed allows to calculate turbine stages with an arbitrary pitch ration of stator and rotor blades. The unsteady forces acting on the rotor blades in axial, tangential and radial directions were found. Due to non-uniform pressure distribution the low frequency excitation appeared. Values of the low frequency excitations are greater than the high frequency excitation caused by the stator blades. Next, the total unsteady forces acting on the shaft from all rotor blades in considered stage were calculated. Values of unsteady forces are very small in comparison to the single blade. The low frequency excitation disappeared. The high frequency excitation is depended on the number of rotor blades.