2012 - Publications Repository - Gdańsk University of Technology

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Publications from the year 2012

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Experience based enhanced decision support for business processes
- Bartosz Kuchaesji
- Edward Szczerbicki
2012
Przedstawiono koncepcje wspomagania procesow biznesowych poprzez wprowadzneie do modelu zbioru doswiadczen.
Experimental and numerical study on deformed steel columns subjected to impact load during earthquakes
- Wojciech Migda
- Robert Jankowski
2012
The soft-storey failure is one of the most typical types of damage observed in buildings during earthquakes. The failure of an upper soft storey of a structure results in large impact load acting on the lower floors and if the resistance of the structural members of the lower storeys is not sufficient it may further lead to progressive collapse of the whole building. The aim of the present paper is to investigate the dynamic behaviour of horizontally deformed steel columns (deformation as the result of earthquake loading) that are additionally subjected to vertical impact load. Steel columns with high slenderness ratio were considered in the study. Both experimental tests and numerical analysis were carried out. In the experiment, impact load was generated by a steel sphere dropped onto a pad of technical clay, so as to simulate nearly plastic impact observed in the reality during earthquakes. The detailed numerical analysis using the FEM was later conducted after verification of the accuracy of the numerical model created. The results of the study indicate that with the increase in the pre-deformation of a column the value of the peak force acting on its top as well as the peak mean normal stress value show a considerable increase trend. Moreover, with the increase in the pre-deformation, the peak horizontal displacement of the middle part of column substantially increases for all height drop values considered. The above conclusions show that the deformation of columns introduced as the result of vibrations due to earthquake loading has a substantial negative influence. The results indicate, however, that even the deformed column is still capable to carry considerable dynamic load before its failure due to stability loss.
Experimental determination of basic mechanical properties of elastomeric polymer
- Tomasz Falborski
2012
There are a lot of different methods of repairing and reinforcing damaged structures, but when it comes to historical buildings and other cultural heritage objects, it is as much about mechanical safety as the aesthetical aspects. Recently, a new and innovative method of repairing damaged structures by filling the cracks with a specially prepared polymer mass has been proposed. This new and innovative technique, known as the Flexible Joint Method (FJM), is mainly dedicated to masonries and historical objects, where minimum intervention is permitted. The flexible joint bonds the disrupted elements and ensures further safe exploitation of a damaged structure. The aim of the present paper is to show the results of the experimental study focused on determining the basic mechanical properties of the elastomeric polymer used for the injections. The results of the study exhibit highly non-linear time-dependent behaviour of the analyzed material. A clear correlation between strain rate and stress was observed. Finally, the hysteretic behaviour of the elastomeric polymer confirms its potential to dissipate the energy in case of dynamic excitations.
Experimental determination of dynamic properties of cylindrical steel tank model filled with liquid
- Daniel Burkacki
- Robert Jankowski
- Tomasz Falborski
2012 Technology and Art
In technical branches, such as chemical or petroleum industries, cylindrical steel tanks are essential structures used for storage of liquid products. Any failure might have disastrous consequences, therefore their safety and reliability is essential. The aim of the present paper is to show the results of the experimental study which has been conducted on a scaled model of a real tank used in Poland. The investigation was carried out using the shaking table. The study included impact tests with modal analysis and harmonic tests of dynamic properties. The influence of liquid level on the natural vibration modes and natural frequencies has been investigated. The results of the study indicate that stored product may significantly influence the values of dynamic parameters.
Experimental examination of an elastomeric polymer
- Tomasz Falborski
- Michał Strankowski
- Łukasz Piszczyk
- Robert Jankowski
- Arkadiusz Kwiecień
2012 Technology and Art
A new method of repairing damaged structures by filling the cracks with a specially prepared elastomeric polymer mass has been recently proposed. This new and innovative technique, known as the Flexible Joint Method (FJM), is mainly dedicated to masonries and historical objects, where minimum intervention is permitted. The flexible joint bonds the disrupted elements and ensures further safe exploitation of a damaged structure. The aim of the present paper is to show the results of the experimental study focused on determining the properties of the polymer mass used for the injections. The polymeric specimens were subjected to static tension and compression tests. The DMA tests were performed to measure the glass transition temperature of an analyzed material and also to determine the elastic modulus (storage modulus), viscous modulus (loss modulus) and damping properties as a function of temperature.
Experimental investigation of M-shape heat transfer coefficient distribution of R123 flow boiling in small-diameter tubes
- Dariusz Mikielewicz
- Michał Klugmann
- Jan Wajs
2012 Full text HEAT TRANSFER ENGINEERING
W publikacji przedstawiono wyniki badań wrzenia czynnika R123 w srebrnych rurkach o małych średnicach (średnice wewnętrzne wynosiły odpowiednio 1.15 mm i 2.3 mm). Badania przeprowadzono w szerokim zakresie stopnia suchości pary (0.01-0.9), gęstości strumienia masy (650-3000 kg/(m2s)) oraz gęstości strumienia ciepła (40-80 kW/m2). W badaniach wykazano, że istnieją dwa lokalne maksima współczynnika przejmowania ciepła w jego profilu wykreślonym w funkcji stopnia suchości pary.
Experimental Investigation of Prototype Water-Lubricated Compliant Foil Bearings
- Artur Olszewski
- Michał Wodtke
- Piotr Hryniewicz
2012 Key Engineering Materials
Praca zawiera wyniki badań doświadczalnych prototypowego łożyska foliowego smarowanego wodą. Łożyska tego typu mogą mieć zastosowanie w węzłach, od których wymaga się ekologicznego środka smarowego, np. pompy wodne czy turbiny wodne. W opracowaniu zademonstrowano wyniki badań trzech prototypowych poprzecznych łożysk foliowych. Opisano napotkane problemy badań oraz wprowadzonych do konstrukcji łożyska zmian, których celem była poprawa badanych parametrów działania łożyska.
Experimental Investigation of the ORC System Elements of a Home Cogenerative Micro Power Plant
- Tomasz Kaczmarczyk
- Eugeniusz Ihnatowicz
- Jarosław Mikielewicz
- Dariusz Mikielewicz
2012
W pracy przedstawiono wyniki badań obiegu ORC z prototypową pompą czerpakową czynnika roboczego HFE 7100 i elektrycznym przepływowym podgrzewaczem oleju termalnego w układzie ORC bez regeneracji. Z analizy wyników badań wynika, że w obiegu ORC bez regeneracji z zaworem rozprężnym (symulującym pracę mikroturbiny) osiągnięto przegrzanie par czynnika niskowrzącego HFE 7100. Uzyskano powtarzalność wyników badań wykonanych serii pomiarowych oraz sprawdzono działanie elementów układu ORC (wymienników ciepła, pomp obiegowych i aparatury kontrolno pomiarowej). Daje to podstawy do kontynuowania badań z mikroturbiną.
Experimental investigations of commercial gas boiler as a heat source for the domestic micro-CHP
- Dariusz Mikielewicz
- Jan Wajs
- Jarosław Mikielewicz
2012
W pracy przedstawiono wyniki badań przeprowadzonych na prototypowym stanowisku mikrosiłowni domowej ORC z kotłem gazowym jako źródłem ciepła. Wykazano, iż jest możliwa adaptacja komercyjnego kotła gazowego dla potrzeb kogeneracji w skali mikro.
Experimental investigations on condensation in flow of HFE-7100 in small diameter channels
- Dariusz Mikielewicz
- Rafał Andrzejczyk
- Michał Klugmann
- Jan Wajs
2012
W pracy przedstawiono wyniki badań eksperymentalnych kondensacji czynnika HFE-7100 w minikanale o średnicy wewnętrznej 2.3 mm. Opisano również oryginalne podejście w prowadzeniu badań nad uzyskaniem lokalnych wartości współczynnika przejmowania ciepła podczas kondensacji w przepływie.
Experimental investigations on condensation in flow of HFE-7100 in small diameter channels
- Dariusz Mikielewicz
- Rafał Andrzejczyk
- Michał Klugmann
- Jan Wajs
2012
In the paper the authors present investigations of flow condensation with the use of the HFE-7100 as a working fluid. The original and new approach to removing the heat from the channel was applied. The research was carried out using a wide-range real time observations, e.g. using infrared camera and stroboscope microphotography. This paper presents the details of experiment as well as the influence of heat and flow parameters on heat transfer coefficient and flow structures for the case of single vertical silver tube of 2.3 mm inner diameter.
Experimental Research of Implant-Fascia Connections
- Agnieszka Tomaszewska
2012
W pracy przedstawiono wyniki identyfikacji siły zrywającej połączenie implantu z powięzią wykonane z użyciem różnych typów łączników: zszywek lub szwów chirurgicznych. Rozważono pięć typów łączników i pięć typów implantów.
Experimental research on technical fabric of the Forest Opera Roof in Sopot
- Krzysztof Żerdzicki
- Paweł Kłosowski
- Krzysztof Woźnica
2012 Machine Dynamics Research
The experimental analysis of the technical fabric Valmex is presented. The study involves uniaxial tensile, cyclic, rheological and biaxial tests. Some of the main differencies between two types of the analysed material have been identified. Mechanical properties of the textile have been modeled by the viscoelastic standard model with quite good effect.
Experimental study of boiling heat transfer in the stagnation point of water microjet
- Tomasz Muszyński
2012
In the paper presented is a comparison of computational model with experimental data. Numerical model of liquid film with phase change in the stagnation zone due to impingement of the microjet is more widely presented in authors previous work. The radius on which theevaporation process is taking place can be determined from the energy balance on the element of the plate. That radius has also been confirmed experimentally in the course of previous work, showing a very good consistency. The model enables determination of the evaporating film thickness. Knowledge of film thickness allows to estimate the heat transfer coefficient. The experimental data will be presented to show the consistency of the postulated model
Experimental Study of Dapped-End Beams Subjected to Inclined Load
- Krystyna Nagrodzka-Godycka
- Paweł Piotrkowski
2012 ACI STRUCTURAL JOURNAL
This paper presents the results of an experimental investigation of the reinforced concrete (RC) dapped-end beams loaded with inclined forces, compared to identical ones loaded with vertical forces only. Such a load may occur in, for example, Gerber's joints or in dapped-end beams supported on corbels, where the vertical gravitation force is additionally completed with horizontal forces caused by temperature differences, shrinking, or creeping. The problem of the state of stresses, cracking, and load capacity of dapped ends subjected to inclined forces, has not been experimentally sufficiently recognized. In the authors' opinion, the results of the presented investigation establish conclusions that are useful in the theoretical verification of that type of structure
Experimental study on shear localization in granular materials within combined strain and stress field
- D. Leśniewska
- Maciej Niedostatkiewicz
- Andrzej Tejchman-Konarzewski
2012 STRAIN
Lokalizacja odkształceń stycznych w materiałach granulowanych była przedmiotem badań doświadczalnych podczas przemieszczania się sztywnej ścianki. Wykonano pomiary przemieszczeń stosując metodę korelacji obrazów cyfrowych. Natomiast pomiary średnich naprężeń wykonano stosując metodę foto-sprężystości. Zastosowano jako materiał granulowany piasek oraz szklane kulki.
Experimentation, material modelling and simulation of bonded joints with a flexible adhesive
- Izabela Lubowiecka
- Mar RODRíGUEZ
- Elena RODRíGUEZ
- David MARTíNEZ
2012 INTERNATIONAL JOURNAL OF ADHESION AND ADHESIVES
The paper deals with material parameters identification of a flexible adhesive and the numerical simulation of its behaviour in a single lap bonded joint. The material modelling was based on the simple shear and tensile-shear laboratory tests of the bonded joints made of thin aluminium and polyurethane plates with the flexible adhesive Terostat MS 9360 manufactured by Henkel AG & Co. The adhesive was considered as a hyperelastic material. The nonlinear analysis of the joints was conducted in ABAQUS finite element program. The experiment and the simulation of a boat fender made of polyurethane with adhesive joints were performed. The test results were used to validate the simulation and the obtained characteristics of the hyperelastic materials.
Experiments and numerical modeling of meat and bone meal pyrolysis in a rotary kiln
- Paweł Ziółkowski
- Marcin Kantorek
2012
The paper presents aspects of modelling the pyrolysis of meat and bone meal (MBM) in a rotary kiln. The pyrolysis of MBM produces a solid fraction which can be used as a fuel, a liquid fraction with potential chemical applications and a low heating value gas. The meat and bone meal pyrolysis was carried out at the temperature of 900 oC. Main features of experiments and numerical model of the pyrolysis were described. The model was validated by comparing the calculated values to measurement. The results of numerical model agree well with the experimental data. The numerical calculations have been carried out in the CFM (Computational Flow Mechanics) code.
EXPERIMENTS AND SIMULATIONS FOR LAPAROSCOPICVENTRAL HERNIA REPAIR IMPROVEMENT
- Agnieszka Tomaszewska
- Izabela Lubowiecka
- Czesław Szymczak
- Maciej Śmietański
- Paweł Kłosowski
- Błażej Meronk
- Kamil Bury
2012 JOURNAL OF BIOMECHANICS
The authors conducted a wide experimental and numerical study in order to determine effective approaches in the laparoscopic VH repair. At first the study covered identification of mechanical properties of the abdominal fascia, implants, tacks and transabdominalsutures. Basis on these data, the one and two-dimensional mathematical models were formulated and a number of numerical static and dynamic analyses were carried out. Then various physical models of the fascia-mesh system were built in many configurations, using a porcine fascia, a few kinds of implants and tacks.
Explanation of Reduction of Pressure Forces in Turbine Chamber Seals
- Krzysztof Kosowski
- Robert Stępień
2012
The paper describes a chamber seal reducing the aerodynamic forces created in shroud seals. Asymmetrical pressure distribution (due to rotor-stator eccentricity) in the blade tip clearance leads to the creation of pressure forces acting on the blade shroud. By increasing the volume above the shroud, the pressure distribution becomes more uniform on the whole shroud circumference and the effect of rotor eccentricity is reduced. It can be easily performed by introducing an extra chamber to the typical turbine blade seals. The circumferential flows in the chamber result in the decrease in the pressure differences and finally in the decrease in aerodynamic forces acting on the whole turbine rotor. A great deal of experimental and numerical research has been carried out to achieve a better explanation of the flow phenomenon and principle of operation of the chamber seals for different types of blade shrouds. The results with the appropriate comments and explanations are presented in the paper. The investigations were carried out for different types of shrouds, various shapes and dimensions of the chambers, and for different turbine working conditions. The proposed chamber seal can remarkably reduce aerodynamic forces generated in the labyrinth type shroud seals, sometimes even by more than 60%.