Filip Wasilczuk, Paweł Flaszyński, Piotr Kaczyński, Ryszard Szwaba, Piotr Doerffer, Krzysztof Marugi,
The paper presents the passive flow control technique, called ‘air curtain’ that reduces the leakage through the shroud sealing of a turbine rotor. The pressure difference between the shroud domains is used to generate a high velocity jet in the clearance between the seal and the casing. A seal with the air curtain is compared to the reference seal by experimental and numerical investigations. It is proven that that leakage is reduced when the air curtain is applied. The effectiveness of the leakage ...
Tópico(s): Aerodynamics and Fluid Dynamics Research
2021 - Elsevier BV | Aerospace Science and Technology
Ryszard Kaczyński, Barbara Grabowska-Olszewska,
This paper is an attempt to evaluate the expansivity of the main genetic types of Polish clays which very often are considered as a bedground for engineering structures. Lithological characteristics and basic physical properties presented in this paper concern the soils of (I) Quaternary age: Boulder clays and glaciolacustrine clays, (II) Tertiary continental and marine clays: Mio-Pliocene clays of Poznan series, Miocene clays of the Carpathian Foredeep (unweathered and weathered), bentonites and bentonitic ...
Tópico(s): Geotechnical and construction materials studies
1997 - Elsevier BV | Applied Clay Science
The main objective of the study was determine the loading history and establish the current state of consolidation of Neogene clays, to study their lithological and microstructural properties, and to define their geological-engineering properties. To accomplish this task, series of laboratory and field tests were performed. The tests were made on clays taken from pits excavated for underground stations and tunnels (A-14-A-15) in Warsaw and from 2 borehole cores taken from the Stegny experimental ...
Tópico(s): Soil and Unsaturated Flow
2010 - Polish Geological Institute | Geological Quarterly
Filip Wasilczuk, Paweł Flaszyński, Piotr Kaczyński, Ryszard Szwaba, Piotr Doerffer, Krzysztof Marugi,
Purpose The purpose of the study is to measure the mass flow in the flow through the labyrinth seal of the gas turbine and compare it to the results of numerical simulation. Moreover the capability of two turbulence models to reflect the phenomenon will be assessed. The studied case will later be used as a reference case for the new, original design of flow control method to limit the leakage flow through the labyrinth seal. Design/methodology/approach Experimental measurements were conducted, measuring ...
Tópico(s): Mechanical and Thermal Properties Analysis
2018 - Emerald Publishing Limited | Aircraft Engineering and Aerospace Technology
Piotr Kaczyński, Ryszard Szwaba, Filip Wasilczuk, Paweł Flaszyński, Piotr Doerffer,
This paper contains experimental and numerical investigation of the leakage flow over the blade tip in turbine stage. Experiments were conducted in non-rotating linear channel. Test rig was intended to model the geometry of the labyrinth seal of the blades of the lower pressure turbine stage. Investigated model contained two different geometries of labyrinth fins. Moreover smooth and honeycomb stator landing were tested. Experimental measurements have been supported by CFD simulation which gives ...
Tópico(s): Heat Transfer Mechanisms
2018 - IOP Publishing | Journal of Physics Conference Series
Filip Wasilczuk, Paweł Flaszyński, Piotr Kaczyński, Ryszard Szwaba, Piotr Doerffer, Krzysztof Marugi,
Abstract This article presents investigations of mass flow reduction in a gap above a fin by the air curtain technique. The proposed method uses slots in the fin to generate a bypass flow and to create a fluidic barrier in the gap above the fin. Both numerical and experimental researches were conducted and the air curtain proved to be effective, showing the mass flow reduction up to about 20%. The comparison of numerical simulations and experimental data showed good agreement, and the flow structure ...
Tópico(s): Plasma and Flow Control in Aerodynamics
2020 - ASM International | Journal of Fluids Engineering
Mio-Pliocene clays will increasingly constitute the subgrade for building structures, not only in the Warsaw region, but within the whole of central Poland, where the depths of their occurrences range from 2 to 100 m below groundlevel and their average thickness is 50 m. In their geological history these clays became overconsolidated. They include numerous weakness surfaces, are sensitive to the influence of exogenic processes, and can be classified as soils of specific properties. It is necessary ...
Tópico(s): Grouting, Rheology, and Soil Mechanics
2002 - De Gruyter | Acta Geologica Polonica
Agnieszka J. Bednarska, Łukasz Mikołajczyk, Elżbieta Ziółkowska, Karolina Kocjan, Agnieszka Wnęk, Jaya Sravanthi Mokkapati, Dariusz Teper, Piotr Kaczyński, Bożena Łozowicka, Renata Śliwińska, Ryszard Laskowski,
Agricultural landscapes have changed substantially in recent decades, shifting from the dominance of small fields (S) with diverse cropping systems toward large-scale monoculture (L), where landscape heterogeneity disappears. In this study, artificial nests of the red mason bee, Osmia bicornis, were placed in S and L landscape types on the perimeter of oilseed rape fields representing different oilseed rape coverages (ORC, % land cover). The local landscape structure around each nest was characterised ...
Tópico(s): Insect and Arachnid Ecology and Behavior
2021 - Elsevier BV | The Science of The Total Environment
Paweł Flaszyński, Piotr Doerffer, Ryszard Szwaba, Piotr Kaczyński, Michał Piotrowicz,
Tópico(s): Aerodynamics and Fluid Dynamics Research
2015 - Springer Science+Business Media | Journal of Thermal Science
Ryszard Szwaba, Piotr Kaczyński, Piotr Doerffer,
The main objective of this research is to study experimentally the effect of transition on the flow structure of the shock wave boundary layer interaction in the blades passage of a compressor cascade. For this purpose a model of a turbine compressor passage was designed and assembled in a transonic wind tunnel. In the experiment the distributed roughness with different heights and locations was used to induce transition upstream of the shock wave. Three locations of distributed roughness in form ...
Tópico(s): Particle Dynamics in Fluid Flows
2018 - Elsevier BV | Aerospace Science and Technology
DETERMINATION OF PERMEABILITY COEFFICIENTS OR LOW-PERMEABLE, SEMI-PERMEABLE AND PRACTICALLY IMPERMEABLE SOILS Summary Permeability properties of soils are of considerable importance for engineering-geological and hydrogeological estimation of the terrain. They determine the co-operation between the engineering object and building substratum. Determination of values of permeability coefficients is of great significance in the evaluation of filtration conditions in the areas of dam axis and dam abutments, ...
Tópico(s): Geology and Environmental Impact Studies
1969 - | Przegląd Geologiczny
Ryszard Szwaba, Piotr Kaczyński, J.J. Telega, Piotr Doerffer,
Tópico(s): Heat transfer and supercritical fluids
2017 - Springer Science+Business Media | Journal of Thermal Science
Ryszard Kaczyński, Jerzy Trzciński,
In the light of the investigations, it has been found that the boulder clays of Pomeranian and Leszno phases have not generally reached the full consolidation. In most cases, illite is the main clay mineral, and in few cases it is montmorillonite. The physical properties (specific density, volume density, natural water content, liquid limit, plastic limit, soaking and swelling) and the mechanical properties (angle of the internal friction, cohesion) of both types of boulder clays are very much alike, ...
Tópico(s): Geology and Environmental Impact Studies
2013 - Polish Geological Institute | Geological Quarterly
Ryszard Kaczyński, Jerzy Trzciński,
Tópico(s): Geotechnical and Mining Engineering
1997 - | Przegląd Geologiczny
Ryszard Szwaba, Piotr Kaczyński, Piotr Doerffer, J.J. Telega,
Tópico(s): Turbomachinery Performance and Optimization
2016 - Springer Science+Business Media | Journal of Thermal Science
Ryszard Kaczyński, Stanisław J. Matysiak,
The problem of mechanics of periodically stratified soils which can be observed in the cases of varved clays, Miocene clays and flotation wastes are considered. The paper contains a description of layered soils and a presentation of certain homogenized model of periodic two-layered fluid-saturated porous solids based on Biot’s theory of consolidation. The example important from the view point of engineering geology applications is solved.
Tópico(s): Geotechnical Engineering and Soil Mechanics
2013 - Polish Geological Institute | Geological Quarterly
Piotr Kaczyński, Ryszard Szwaba,
The shock wave boundary layer interaction on the suction side of a transonic turbine blade was one of the main objectives of the TFAST project. For this purpose a model of a turbine passage was designed, manufactured and assembled in a transonic wind tunnel. The paper presents the experimental investigations concerning the flow structure on the transonic turbine blade. A clean case (without a cooling system) with a normal shock wave interacting with a laminar boundary layer and also the influence ...
Tópico(s): Computational Fluid Dynamics and Aerodynamics
2016 - IOP Publishing | Journal of Physics Conference Series
Piotr Kaczyński, Ryszard Szwaba, Michał Piotrowicz, Paweł Flaszyński, Piotr Doerffer,
Abstract Presented work is focused on analysis of the flow over the 2D model of Airbus A320 airfoil wing in cruise phase of the flight. For this purpose the measurement channel with an airfoil model was designed and assembled in a transonic wind tunnel to obtain a similar flow pattern as in the reference two-dimensional freestream flow. Experimental investigations were conducted in the IMP PAN transonic wind tunnel with a relative narrow test section which is a novel approach in terms of these type ...
Tópico(s): Computational Fluid Dynamics and Aerodynamics
2022 - IOP Publishing | Journal of Physics Conference Series
Paweł Flaszyński, Piotr Doerffer, Ryszard Szwaba, Michał Piotrowicz, Piotr Kaczyński,
Tópico(s): Aerodynamics and Fluid Dynamics Research
2018 - Springer Science+Business Media | Journal of Thermal Science
Andrzej Drągowski, Kaczyński Ryszard, Joanna Pinińska,
Tópico(s): Industrial Engineering and Technologies
1983 - Springer Science+Business Media | Bulletin of Engineering Geology and the Environment
SHEAR STRENGTH OF SOILS UNDER HIGH PRESSURE CONDITIONS Summary The paper presents results of laboratory tests of shear strength of soils under pressure changing from 0 to 200 kG/cm2. The studies were carried out on samples of soils from the blanket of open-cast brown coal mine from Belchatow and sulphur mine from Machow. They were carried out with the use of a special apparatus to triaxial compression with a possibility of measuring pore pressure during shearing and outflow of water consolidation. ...
Tópico(s): Structural Engineering and Materials Analysis
1977 - | Przegląd Geologiczny
Ryszard Kaczyński, Janusz Muchowski,
Najbardziej charakterystycznymi typami powierzchniowych ruchow masowych na zboczach zbudowanych z ilow krakowieckich w dolinie Wisly i Sanu są klasyczne osuwiska, zsuwy i spelzywanie. O stateczności tych zboczy decydują przede wszystkim powierzchnie oslabienia i resztkowe parametry wytrzymalości na ścinanie. Okres stabilizacji zboczy w ilach krakowieckich zalezy od drenazu wod i w przypadku zboczy silnie zawodnionych jest on dlugotrwaly. MASS MOVEMENTS ON THE SLOPES COMPOSED OF THE KRAKOWIEC CLAYS ( ...
Tópico(s): Geological Formations and Processes Exploration
1987 - Polish Geological Institute | Geological Quarterly
Andrzej Drągowski, Zygmunt Glazer, Ryszard Kaczyński, Joanna Pinińska,
GEOTECHNICAL PROPERTIES OF SELECTED POLISH SOILS Summary The Department of Mechanics and Foundation Engineering, Faculty of Geology, Warsaw University, has been active in continuous research works on soils of Poland. The most of activity is oriented on consulting and expert's reports. For years many detail expertises and general reports on soil conditions were done, resulting in methodical solutions of engineering problems of siting of hydro, mine and industrial objects in difficult or unsual conditions. ...
Tópico(s): Waste Management and Environmental Impact
1989 - | Przegląd Geologiczny
Tópico(s): Drilling and Well Engineering
1975 - Springer Science+Business Media | Bulletin of Engineering Geology and the Environment
A. Szummer, Ryszard Kaczyński, E. T. Stępkowska,
MORPHOLOGY OF MARINE CLAYS AT THE EXAMPLE OF CLAY AT THE EXAMPLE OF CLAY SEDIMENTS FROM CHMIELNIK AND MACHOW Summary Deep drillings recently made in seas and oceans and the necessity to analyse seafloor deposits as foundation soil for drilling platforms arise interest in morphology and structure of these deposits. The available data from studies on samples of such deposits are still rather innumerous so the author presents results of detailed studies on marine clays, nowadays occurring in land areas ...
Tópico(s): Waste Management and Environmental Impact
1982 - | Przegląd Geologiczny
SHEARING STRENGTH TESTS OF ALBIAN SANDS FROM THE LUBLIN COAL BASIN Summary The paper presents results of trfaxial compression tests of Albian sands. The samples were taken in the frozen state at the depth of 600 m below terrain surface in one of mines in the Lublin Coal Basin. The strength studies involved tests with loading applied in traditional way (i.e. by increasing vertical loading under conditions of constant horizontal stress and with or without drainage) and those made under conditions of ...
Tópico(s): Grouting, Rheology, and Soil Mechanics
1987 - | Przegląd Geologiczny
Ryszard Kaczyński, Janusz Muchowski,
Tópico(s): Integrated Water Resources Management
1988 - Springer Science+Business Media | Bulletin of Engineering Geology and the Environment
Tópico(s): Polish Historical and Cultural Studies
2002 - | Przegląd Geologiczny
Ryszard Kaczyński, A Bakowska, K Kielbasinski,
Tópico(s): Geotechnical and Mining Engineering
2008 - | Acta Scientiarum Polonorum Architectura
Tópico(s): Geology and Environmental Impact Studies
2008 - | Acta Scientiarum Polonorum Architectura