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1
Content available Application of Rapid Prototyping technology in the manufacturing of turbine blade with small diameter holes
Deja M., Dobrzyński M., Flaszyński P., Haras J., Zieliński D.
Polish Maritime Research
|
2018
|
S 1
119--123
EN
The article presents the possibilities++ of using Rapid Prototyping (RP) technology in the manufacturing of turbine blades with small diameter holes. The object under investigation was gas turbine blade with small diameter cooling holes and holes for generating longitudinal vortices. A turbine blade model was produced by means of Direct Metal Laser Sintering (DMLS) technology and subsequently validated in terms of detection and accuracy of the obtained holes. The application of the computer tomography and digital radiography technique resulted in obtaining a series of cross-sections of the turbine blade model with a series of holes. Particular attention was pointed out at the investigation of the locations of micro-holes with a diameter of 0.3 mm. It turned out that it was impossible to make such small holes by the RP method. In the following part the results of the study on the possibilities of making the micro-holes using electrical discharge method have been presented. In addition, proposition of further works such as the development of the considerations and issues discussed in this article, has been offered.
2
Content available Identification of the causes of increased vibrations in the high-power multi-stage rotodynamic pump
Żywica G., Flaszyński P., Kaczmarczyk T. Z., Kopeć H.
Diagnostyka
|
2018
|
Vol. 19, No. 3
81--88
EN
The article discusses the vibrodiagnostic tests of a multi-stage high-power rotodynamic pump. The tested pump was operated as a feed water pump in an industrial combined heat and power plant. However, some time ago, its dynamic performance started to deteriorate. Therefore, diagnostic tests were carried out, the aim of which was to identify the reasons for the increased vibration level and to minimise it. The scope of the performed work included both the analysis of possible excitation forces originating from the flow system and measurements of the pump vibrations at different power levels. Additionally, at selected measuring points, vibration velocity spectra were registered and eigenfrequencies were determined. The analysis of the obtained results allowed to clearly identify the causes of dynamic problems and introduce changes that enable their elimination.
PL
W artykule omówione zostały badania wibrodiagnostyczne wielostopniowej pompy wirowej o mocy 3 MW. Badana pompa pracowała jako pompa wody zasilającej w elektrociepłowni przemysłowej, ale od pewnego czasu jej stan dynamiczny pogarszał się. Dlatego przeprowadzone zostały badania diagnostyczne, których celem była identyfikacja przyczyn podwyższonego poziomu drgań oraz ich minimalizacja. Zakres wykonanych prac obejmował zarówno analizę możliwych wymuszeń pochodzących z układu przepływowego jak i pomiary wielkości charakterystycznych drgań pompy przy różnych poziomach mocy. Dodatkowo, w wybranych punktach pomiarowych, zarejestrowano również rozkłady częstotliwościowe drgań i wyznaczono częstotliwości drgań własnych. Analiza uzyskanych wyników pozwoliła na jednoznaczną identyfikację przyczyn problemów dynamicznych oraz wprowadzenie zmian umożliwiających ich eliminację.
3
Content available An investigation of hot spot location at turbine inlet – numerical simulations for factor project test rig
Flaszyński P., Piotrowicz M.
Transactions of the Institute of Fluid-Flow Machinery
|
2017
|
nr 135
101--115
EN
The main objective of the presented paper is the investigation of a flow structure and parameters distribution downstream of combustor simulator and its effect on turbine inlet. The investigations are carried out by means of numerical simulations for combustor and turbine nozzle guide vane configuration existing at test rig in DLR Goettingen. As the effect, the hot spot location for different relative positions of the swirler and nozzle guide vanes is shown. The presented results are obtained within a pre-test simulations supporting the final design of the test section and they allow to draw conclusions for the required limiting cases investigated experimentally. The location of the hot spot is highly important for thermal loading of the first stage rotor.
4
Content available Source term model for streamwise Rod Vortex Generator modelling
Kwiatkowski T., Flaszyński P.
Journal of KONES
|
2016
|
Vol. 23, No. 4
261--268
EN
In the article, the new method of modelling of Rod Vortex Generators (RVGs) was proposed. RVGs are inclined rods, mounted in boundary layer used to flow control. RVGs were intensively investigated in Institute of Fluid-Flow Machinery in Gdansk, Poland. The research results indicate high potential of RVGs to flow control in wide range of Mach numbers (Mach 0.3-1.45) in the main flow. Due to the flow structure details generated by RVG, it is required to create fine grids in the vicinity of RVGs, which increase the computational cost. In order to overcome this difficulty and reduce computational cost the new numerical models of RVGs are proposed, which use the modification of BAY model. Using BAY model it is not needed to resolve the shape of RVG in detail and it is possible to use orthogonal meshes. The BAY model was originally proposed to predict flows behind thin-plate vortex generators. This model works by adding momentum source term to Reynolds-Averaged Navier-Stokes equations in ANSYS Fluent. The BAY model spatial vectors orientation was modified and some simplifications were performed. The model was calibrated and simulations were carried out for the single rod. The results and effectiveness of modified BAY model were compared with wind-tunnel experiment results and grid-resolved model.
5
Content available Numerical simulations of gap flow above rotating disk
Wasilczuk F., Flaszyński P., Doerffer P.
TASK Quarterly : scientific bulletin of Academic Computer Centre in Gdansk
|
2015
|
Vol. 19, No 2
89--100
EN
A rotating disk can be considered a basic configuration for the investigations of the impact of various conditions on the flow through the clearance between the shrouded turbine blade and the casing. Numerical calculations using Fine/Turbo Numeca were conducted to examine the influence of the rotational velocity and the pressure difference across the disk on the flow conditions, especially the mass flow through the clearance. The results were validated using the experimental data. Moreover, the flow field was investigated to reveal the vortices induced in the flow. The calculations showed a significant drop of the mass flow with a rise of the rotation velocity. Additionally, the vortex created upstream of the disk at higher rotation velocities was observed. The phenomenon of separation at the edge of the disk was investigated.
6
Content available Influence of limiting walls on shock wave structure in single passage test section with compressor profile
Piotrowicz M., Flaszyński P., Szwaba R.
TASK Quarterly : scientific bulletin of Academic Computer Centre in Gdansk
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2015
|
Vol. 19, No 2
141--152
EN
The shock wave boundary layer interaction on the suction side of a transonic compressor blade is one of the main objectives of the TFAST project (Transition Location Effect on Shock Wave Boundary Layer Interaction). In order to look more closely into the flow structure on the suction side of the blade, a design of a turbine passage model in a rectilinear transonic wind tunnel was proposed. The model which could reproduce the flow structure, the shock wave location, the pressure distribution and the boundary layer development similar to the obtained in a reference cascade profile is the main objective of the design presented here. The design of the proposed test section is very challenging, because of the existence of a shock wave, its interaction with the boundary layer and its influence on the 3-D flow structure in the test section. The paper presents the influence of the test section geometry configuration on the flow structure as an effect of the shock wave boundary layer interaction.
7
Content available 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
|
2015
|
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.
8
Content available 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
|
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.
9
Content available Numerical prediction of steady and unsteady tip vortex cavitation on hydrofoils
Flaszyński P., Szantyr J. A., Tesch K.
Polish Maritime Research
|
2012
|
nr 3
3-15
EN
The article presents the numerical method for prediction of tip vortex cavitation generated on hydrofoils. This method has been developed in the course of numerical and experimental research described in earlier publications. The objective of the research was to design the optimum discrete grid structure for this specific computational task and to select the best turbulence model for such an application The article includes a short description of the method and a computational example demonstrating its performance. In this example the results of numerical prediction of the cavitating tip vortex obtained from two commercial CFD codes are compared with experimental photographs taken in the cavitation tunnel in the corresponding flow conditions. Altogether nine different flow conditions are tested and analyzed, but only selected results are included. The accuracy of the numerical predictions is discussed and the reasons for minor existing discrepancies are identified. The unsteady tip vortex calculations are also presented, showing the fluctuations of the transverse velocity components predicted for three cross-sections of the cavitating vortex kernel.
10
Content available An Experimental and Numerical Study of Tip Vortex Cavitation
Szantyr J. A., Flaszyński P., Suchecki W., Alabrudziński S.
Polish Maritime Research
|
2011
|
nr 4
14-22
EN
The article presents the results of the research project concerning tip vortex cavitation. This form of cavitation is very important in operation of many types of rotary hydraulic machines, including pumps, turbines and marine propellers. Tip vortex cavitation generates noise, vibration and erosion. It should be eliminated or significantly limited during the design of these types of machines. The objective of the project was to develop an accurate and reliable method for numerical prediction of tip vortex cavitation, which could serve this purpose. The project consisted of the laboratory experiments and numerical calculations. Inthe laboratory experiments tip vortex cavitation was generated behind a hydrofoil in the cavitation tunneland the velocity field around the cavitating kernel was measured using the Particle Image Velocimetry method. Measurements were conducted in three cross-sections of the cavitating tip vortex for a number ofangles of attack of the hydrofoil and for several values of the cavitation index. In the course of numerical calculations two commercial CFD codes were used: Fluent and CFX. Several available approaches to numerical modeling of tip vortex cavitation were applied and tested, attempting to reproduce the experimental conditions. The results of calculations were compared with the collected experimental data. The most promising computational approach was identified. Keywords:
11
Katedra Maszyn Wirnikowych i Mechaniki Płynów w latach 2005-2010
Banaszek M., Biernacki R., Flaszyński P., Iwan J., Puzyrewski R.
Technika Chłodnicza i Klimatyzacyjna
|
2010
|
nr 5
202-206
12
Content available remote Method of Characteristics for Design of Centrifugal Pump Geometry
Puzyrewski R., Zochowski K., Flaszyński P.
TASK Quarterly : scientific bulletin of Academic Computer Centre in Gdansk
|
2010
|
Vol. 14, No 3
249-256
EN
The method of characteristics leads to the blade geometry of a centrifugal pump. The method is built taking the advantage of the governing equations of fluid mechanics written in a non-orthogonal coordinates system. The coordinate system is based on an analytically described boundary of a centrifugal pump. Some of the information concerning the designed geometry should be introduced in advance. The mass conservation equation needs the information of the blockage factor resulting from the blading thickness. In the momentum conservation equation the body force replaces the blading force together with the friction force. In the energy conservation equation the dissipation effects are represented by a loss coefficient. It is shown that while simplifying the body force vector, the set of equations reduces to a hyperbolic system which allows applying the method of characteristics. The shapes of surfaces representing the designed blading can be built from the trajectories of fluid particles.
13
Content available A method for the accurate numerical prediction of the tip vortices shed from hydrofoils
Flaszyński P., Szantyr J. A., Dymarski P., Kraskowski M.
Polish Maritime Research
|
2010
|
nr 2
10-17
EN
The possibly accurate numerical prediction of the detailed structure of vortices shed from the tips of hydrofoils is an important element of the design process of marine propellers. The concentrated tip vortices are responsible for the propeller cavitation erosion and acoustic emission. The purpose of the project described in this paper was to develop the numerical method for prediction of the tip vortex structure. In the course of the project the numerical calculations were confronted with the results of experimental measurements. This led to creation of the specific method of construction of the computational grid and to selection of the optimum turbulence model. As a result the reliable method for the accurate numerical prediction of the concentrated tip vortices for different hydrofoil geometry and flow conditions has been developed and validated. This method enables elimination of the unfavourable phenomena related to the tip vortices in the course of the propeller design calculations.
14
Content available An experimental and numerical study of the vortices generated by hydrofoils
Szantyr J. A., Biernacki R., Flaszyński P., Dymarski P., Kraskowski M.
Polish Maritime Research
|
2009
|
nr 3
11-17
EN
The article presents the results of the research project concerning the process of formation of the tip vortices shed from hydrofoils of different geometry in different flow conditions. Three hydrofoils resembling the contemporary marine propeller blades have been selected for the study. The experimental part of the project consisted of the LDA measurements of the velocity field in three cross-sections of the vortex generated by the hydrofoils in the cavitation tunnel. The numerical part of the project consisted of calculations of the corresponding velocity field by means of three computer codes and several selected turbulence models. The comparative analysis of the experimental and numerical results, leading to the assessment of the accuracy of the numerical methods, is included.
15
Content available A method for analysing ram pressure characteristics of impeller pump rotor
Puzyrewski R., Żochowski K., Flaszyński P.
Polish Maritime Research
|
2009
|
S 1
52-57
EN
This paper presents a method in which typical tests of centrifugal pump are used to obtain information on real value of discharge angle of flow leaving the rotor. The method can be applied to properly choose inlet angle to blade palisade of centrifugal guide vanes in the case when to perform measurements of velocity fields behind the rotor more precisely is not possible.
16
Content available remote Numeryczna analiza trojwymiarowgo przepływu w polimerowym łożysku smarowanym wodą
Flaszyński P., Litwin W.
Tribologia
|
2007
|
nr 1
49-56
PL
Praca prezentuje wyniki obliczeń przepływu trójwymiarowego w obszarze szczeliny łożyska wraz z komorą zasilającą i spływową. Obliczenia wykonano przy zastosowaniu programu FLUENT. Przedstawiono wartości lokalne w postaci rozkładu ciśnienia i temperatury w łożysku oraz charakterystyki globalne: wartości sił i masowego natężenia przepływu. Wyniki obliczeń przedstawiono na tle danych eksperymentalnych dla jednej z wybranych konfiguracji łożyska.
EN
The article deals with water lubricated main shaft bearings. The main idea of this article was to check and present the possibilities of modern CFD software - FLUENT 6.2 as a tool for calculation of hydrodynamic bearings. The results of conducted calculations were compared to measurements. All experimental tests were made on special test stand design and built at the Faculty of Ocean Engineering and Ship Technology of the Gdansk University of Technology. The results of calculated load capacity are similar. The value difference was about 30%. Bigger difference was in measured and calculated pressure field. Probably problem was in measured values.
17
Content available remote Wpływ strat brzegowych w obszarze przepływów wtórnych na kształtowanie wirnika sprężarki promieniowej
Puzyrewski R., Flaszyński P.
Zeszyty Naukowe. Cieplne Maszyny Przepływowe - Turbomachinery / Politechnika Łódzka
|
2006
|
nr 130, vol. 1
153-162
PL
Przedstawiono metodę wyznaczania powierzchni łopatki sprężarki promieniowej opartą o rozwiązanie zadania odwrotnego w ramach modelu osiowosymetrycznego. Wykorzystano korektę Stodoli dla uwzględnienia skończonej ilości łopatek. Pokazano jak zwiększone straty w obrębie obszarów przy dysku i pokrywie wpływają na zmianę kształtu łopatki. Dla przykładowego wirnika wykonano obliczenia typu 3D.
18
Experimental and numerical analysis of a streamwise vortex generator for subsonic flow
Flaszyński P., Szwaba R.
Inżynieria Chemiczna i Procesowa
|
2006
|
T. 27, z. 3/1
985-997
EN
The total pressure measurements at two sections downstream of the jet hole (streamwise vortex generator) for the main flow Mach numbers 0.3 and 0.8 are presented. Experimental data are compared with the numerical results (FLUENT and SPARC) for one jet hole inclination. Differences of the streamwise vortex structures predicted by the codes are compared.
PL
Przedstawiono wyniki obliczeń numerycznych dwoma kodami (FLUENT i SPARC) na tle badań eksperymentalnych generatora wirów wzdłużnych dla liczb Macha przepływu głównego 0.3 i 0.8. Porównano ciśnienie całkowite w dwóch przekrojach za otworem, przez który odbywa się wydmuch. Przedstawiono strukturę wiru wzdłużnego uzyskaną za pomocą obu programów.
19
Content available remote Flow Models 1D, 2D, 3D for Diagonal Pump
Puzyrewski R., Żochowski K., Flaszyński P.
Zeszyty Naukowe. Cieplne Maszyny Przepływowe - Turbomachinery / Politechnika Łódzka
|
2005
|
nr 128, vol. 2
441-448
EN
The sequence of typical models in turbomachinery: 1D, 2D and 3D is presented in the paper. For the one-dimensional model a diagram of energy losses is shown for the pump process. The 2D model is considered as axisymmetrical and the solution of inverse problem has been carried out. Model 3D The 3D model has been used to investigate some details of the flow pattern in rotor designed for a diagonal pump.
20
Content available The inverse problem in a hyperbolic-section radial compressor
Puzyrewski R., Flaszyński P.
Journal of Theoretical and Applied Mechanics
|
2003
|
Vol. 41 nr 4
789-803
EN
A comparison between the inverse method, leading within the framework of the 2D model to prediction of the optimal rotor shape and the direct approach for evaluating flow through a preexisting rotor shape utilizing a 3D model is presented in this paper. The principle of shaping the rotor envelope and blading within the 2D model is illustrated, followed by subsequent computation of 3D flow through the resulting model. The design goal is to obtain uniform distributions of flow parameters within the rotor while avoiding separated flow. It is also shown how the altering of the overall shape of the rotor from conical to hyperboloidal affects the uniformity of velocity distribution upstream of the rotor inlet.
PL
Porównano rozwiązanie zadania odwrotnego w ramach modelu dwuwymiarowego, prowadzącego do kształtu koła wirnikowego, z zadaniem prostym rozwiązanym w ramach modelu trójwymiarowego dla skonstruowanego wirnika. Przedstawiono elementy algorytmu kształtowania łopatek przy wykorzystaniu modelu dwuwymiarowego. W podanym przykładzie wskazano możliwość optymalizacji kształtu jednego z ograniczeń kanału w celu uzyskania równomiernego rozkładu parametrów w przekroju wylotowym. Pokazano jak zmiana obrysu wirnika z klasycznego kształtu stożkowego na hiperboliczny może wpłynąć na równomierność rozkładu pól prędkości przed układem łopatkowym.
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