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1

Comprehensive analysis of tribological factor influence on stress-strain and thermal state of workpiece during titanium alloys machining

Stupnytskyy Vadym, She Xianning

Archive of Mechanical Engineering

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2021

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LXVIII, nr 2

227--248

EN

The article describes how different friction coefficients under certain cutting conditions and parameters affect the formation of the stress-strain and thermal states of the product when titanium alloy machining. A new research methodology is used for the study. Firstly, in the initial data for simulation, each time a different declared coefficient of friction is proposed, and every such task of the cutting process modelling is solved for various cutting parameters. The second stage analyzes how these coefficients influence the stress-strain and thermodynamic state of the workpiece and tool during cutting, as well as the tool wear dynamics. In the third stage of the study, ways for ensuring these analytically-grounded tribological cutting conditions are proposed. The analysis of different wear criteria in the simulation models of titanium alloys cutting is carried out. Experimental studies confirm simulation results.

2

Metoda wyznaczania rozkładu temperatur w uzwojeniu wirnika chłodzonego bezpośrednio wodorem

Gakał P., Owsiannikowa E., Przybysz J., Tretiak A.

Przegląd Elektrotechniczny

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2017

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R. 93, nr 2

43--47

PL

Do analizy stanu cieplnego uzwojenia wirnika chłodzonego bezpośrednio wodorem zastosowano metodę elementów skończonych, która jest stosowana w programie Solid Works. Metoda pozwala trójwymiarowo zbadać stan cieplny z uwzględnieniem różnych rodzajów odprowadzenia ciepła z elementów wirnika oraz nierównomierności warunków wymiany ciepła. W artykule przedstawiono wyniki badań cieplnych turbogeneratora o mocy 550 MW podczas biegu jałowego i trójfazowego zwarcia ustalonego. Badania wykonano w firmie Elektrotiażmasz. Temperatura uzwojenia wirnika wynosiła podczas pracy znamionowej 74,7oC.. Z porównania wyników obliczeń i badań wynika, że różnica między nimi jest mniejsza od 5%.

EN

It is proposed to use the finite element method realized in the computer SolidWorks environment for the analysis of the temperature field of the rotor of 550-MW turbogenerator with direct hydrogen cooling. This technique allows to investigate the thermal state of the rotor in a threedimensional statement, taking into account different types of heat in the elements of the rotor and irregular conditions of heat exchange between cooling medium. The relation for heat transfer coefficient between hydrogen and inner walls of the cooling channels of the rotor winding is proposed to use as a boundary conditions intended for the closure of the mathematical model for the thermal state of the rotor of the turbogenerator. The results of the thermal tests of 550-MW generator in the idling and short circuit are presented in the article. Thermal tests were carried out at the State Enterprise «Plant «Electrotyazhmash». The maximum temperature of the rotor winding at rated lood was 74,7 C. The comparison of the calculated data and test results shows that the difference is less than 5%.

3

The analysis of thermal state of catalytic converter depending on fuel supply and engine load using thermo-vision

Worsztynowicz B., Uhryński A., Borkowski B., Pluta M.

Combustion Engines

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2017

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R. 56, nr 3

30--36

EN

The paper discusses the problem of thermal state of three-way catalytic converter depending on engine load with spark ignition fueled with gasoline and natural gas. The measurements on the test bench were performed, during which the temperature of the exhaust gases in the exhaust system was measured with the help of thermocouples, and at the same time, the track of the thermal state of the catalytic converter was monitored using thermo-vision camera. The stable work of engine with different rotation speed and values of load was considered together with transient states. The results of the measurements were presented in forms of charts and selected thermograms, qualitatively presenting the issue of thermal state of the catalytic converter.

4

Tribological Properties and Microstructure of the Metal-Polymer Composite thin Layer Deposited on a Copper Plate by Electrocontact Sintering

Kovtun V., Pasovets V., Pieczonka T.

Archives of Metallurgy and Materials

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2017

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Vol. 62, iss. 1

51--58

EN

The properties of the electrocontact sintered metal-polymer composite materials are strongly determined by the heat flow taking place during sintering, which, in turn, is influenced by the amount and initial distribution of the polymer particles in the metal matrix. In case of the metal-polymer powder mixture in the form of a thin layer deposited on the bulk metal substrate, the influence of the latter is also taken into consideration. Thus, the model simulating the heating and sintering of the thin layer made of metal-polymer powder mixture on a metal plate is proposed. Based on mathematical calculations relating to the model describing the thermal state of the system, it is shown how heat flow fields are formed within the layer, depending on the polymer content and its distribution. These theoretical simulations seem to be useful in optimising the production of the antifriction metal-polymer layer on a bulk copper substrate by electrocontact sintering. The results of the tribological experiments and microstructural observations are in a good agreement with the theoretical model.

5

Wspomaganie identyfikacji procesów tribologicznych w badaniach innowacyjnych konstrukcji przekładni planetarnych poprzez zastosowanie metody termowizyjnej

Kwaśny M., Spałek J.

Tribologia

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2015

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nr 3

79--88

PL

W opracowaniu przedstawiono w sposób syntetyczny problem wykorzystania metody termowizyjnej do pośredniej identyfikacji pól temperatur generowanych w węzłach tribologicznych (łożyskowania i zazębienia) podczas badań stanowiskowych innowacyjnych konstrukcji planetarnych przekładni zębatych dużych mocy. Zwrócono uwagę na wielokryterialny system oceny funkcjonalności omawianych przekładni i na tym tle na ważność problematyki procesów tribologicznych kształtujących ich stan termiczny.

EN

The paper presents the problem of the use of thermal imaging methods for indirect identification of temperature fields generated in the tribological nodes, such as bearing and meshing, during bench testing of an innovative design of high power planetary gear. Attention is paid to the multi-criteria evaluation system’s functionality in relation to gears and the validity of the problems of tribological processes that shape their thermal state.

6

Układ regulacji i stabilizacji stanu cieplnego silnika spalinowego w warunkach hamowni silnikowej

Iskra A., Babiak M., Wróblewski E.

Logistyka

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2015

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nr 3

1858--1864, CD 1

PL

W artykule przedstawiono modyfikację stanowiska silnikowego na hamowni silnikowej poprzez budowę układu regulacji i stabilizacji stanu cieplnego silnika. Stanowisko zostało wyposażone w specjalne układy regulacji temperatury, zapewniające większą stabilność temperatury niż ma to miejsce w standardowych układach. Podstawowym warunkiem przeprowadzania badań na stanowisku silnikowym jest utrzymywanie powtarzalności warunków przeprowadzania eksperymentu. Omówiono przebudowę układu chłodzenia silnia, chłodzenia powietrza doładowanego oraz układu podgrzewania oleju w misce olejowej. Dodatkowo przeanalizowano wpływ tych układów na stan cieplny silnika oraz uzyskaniu dokładniejszych warunków pomiarowych badań przeprowadzanych na stanowisku silnikowym zamontowanym na hamowni. Sformułowane wnioski pozwalają ocenić wpływ temperatury cieczy chłodzącej, powietrza doładowanego i oleju na straty tarcia w głównych węzłach tarcia silnika spalinowego.

EN

The paper presents a modification of engine test stand by building control and stabilization system of combustion engine thermal state. Test stand has been equipped with special temperature control, providing greater temperature stability than in the case of standard systems. The basic requirement for carrying out the tests on the engine test stand is to keep the repeatability conditions of the experiment. The paper discusses the reconstruction of the factory cooling system, charge air cooling and heating of the oil in the oil sump. In addition, it analyzes the impact of these systems on the thermal state of the engine and obtaining more accurate measurement conditions of tests carried out on a engine test bench. Conclusions allow to assess the impact of the coolant temperature, charge air and oil on the friction losses in the main engine kinematic pairs.

7

Thermal and stress states in unsteady conditions of operation of the rotors of ultra-supercritical parameter turbines

Rusin A., Lipka M., Łukowicz H.

Archiwum Energetyki

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2013

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T. 43, nr 1/2

129--146

EN

The paper presents the results of numerical analyses, including the steam turbine rotor, for a newly designed 900 MW power unit with ultra-supercritical steam parameters (650 oC, 30.0 MPa). With the use of preliminary design calculations and assuming the optimum structural solutions, simulations of the turbine operation in unsteady conditions are carried out. The analyses take account of the turbine start-up from the different thermal states, i.e., the cold, warm and hot states, and with different rates of increment in the steam parameters. The maps of the temperature field and the stress distributions are obtained. Based on them, the areas with the highest level of stress are identified, i.e., the rotor critical areas which have a direct impact on the life of the entire machine. The performed simulations and analyses make it possible, already at the design stage, to determine the ranges of possible values of stress amplitudes occurring in the main components of the turbine. This in turn allows a preliminary assessment of the turbine life.

PL

W pracy przedstawiono wyniki analiz numerycznych, obejmujących wirnik turbiny parowej dla nowoprojektowanego bloku o mocy 900 MW na parametry super-nadkrytyczne (650 oC, 30 MPa). Opierając sie na wcześniej przeprowadzonych obliczeniach projektowych, po przyjęciu optymalnego rozwiązania konstrukcyjnego, przeprowadzono symulację pracy turbiny w warunkach nieustalonych. Analizy uwzględniały rozruchy turbiny zarówno z różnych początkowych stanów cieplnych, tj. zimnego, ciepłego oraz gorącego, jak i realizowanych z różnymi prędkościami przyrostu parametrów pary. Otrzymano mapy rozkładów pól temperatur oraz naprężeń. Na ich podstawie zidentyfikowano obszary o najwyższym poziomie wytężenia, tzn. obszary krytyczne wirnika, które w sposób bezpośredni będą wpływać na żywotność całej maszyny. Przeprowadzone symulacje i analizy pozwalają już na etapie prac projektowych określić zakresy możliwych wartości amplitud naprężeń występujących w głównych elementach turbiny. Pozwala to z kolei na wstępne oszacowanie trwałości turbiny.

8

Stan termiczny i drgania przekładni zębatej przenośnika taśmowego jako funkcja smarowania

Spałek J., Kwaśny M., Spałek S.

Tribologia

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2010

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nr 5

285-294

PL

W opracowaniu przedstawiono wyniki eksploatacyjnych badań drgań i temperatury dwustopniowej przekładni zębatej pracującej w układzie napędowym przenośnika taśmowego. Drgania rejestrowano za pomocą przenośnego miernika drgań typu MD-5U. Określono zależność poziomu drgań RMS od klasy lepkościowej oleju smarującego (zastosowano oleje w klasach lepkości wg ISO: VG 46, VG 68 oraz VG 150) oraz od temperatury roboczej oleju zmieniającej się w cyklu pracy przekładni od jej rozruchu aż do osiągnięcia ustalonego stanu termicznego. Uzyskane wyniki badań wskazują na istotność wpływu lepkości oleju smarującego na stan termiczny i poziom drgań przekładni zębatej pracującej w określonych warunkach eksploatacyjnych.

EN

The paper presents the results of the examination of the influence of lubricating oil viscosity on the vibration level of a two-stage gear transmission working in a belt-conveyor power transmission system. Three classes of oil viscosity were taken into consideration during the research: VG 46, VG 68, VG 150. The dependence of root-mean-square value (RMS value) of the frame vibration amplitude upon the working viscosity of the mentioned oil classes was defined with the help of a MD-54 portable vibration meter. Oil working viscosity varies with change of temperature in transmission working cycle. The research findings show that the application of oil with a higher viscosity class causes reduction of vibration and temperature level of working transmission.

9

Modeling of flow in an evaporator of a nonconventional combustion engine

Hlavna V, Kovalcik A, Toporcer E

Silniki Spalinowe

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2009

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R. 48, SC1

79--85

EN

A nonconventional cooling-combustion engine uses the part of energy bound in a cooling system of a combustion engine for production of the cooling output applicable in motor vehicles. We have given some information about the principle and some other details at preceding conferences. The paper deals with a flow simulation of the working medium in the vaporization container of a cooling circuit of the unconventional combustion engine. Consequently evaporation and thermal states at the atmospheric pressure above the unconventional cooling liquid (solution LiBr – H2O) level in the evaporator are simulated. Limiting conditions for the functionality assurance of the cooling system of the unconventional combustion engine were found by means of a simulation.

10

Stan cieplny polietylenu modyfikowanego wodorotlenkiem glinu

Samujło B.

Czasopismo Techniczne. Mechanika

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2009

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R. 106, z. 1-M

307-311

PL

W artykule przedstawiono wybrane wyniki badań charakterystyk p-v-T oraz parametrów termodynamicznego równania stanu polietylenu dużej gęstości modyfikowanego wodorotlenkiem glinu i innymi środkami pomocniczymi. Ustalono wpływ przeprowadzonej modyfikacji na zmiany zależności objętości właściwej polietylenu od temperatury i ciśnienia, kinetykę krystalizacji oraz parametry termodynamicznego równania stanu Taita.

EN

The selected results of p-v-T characteristic and Tait's thermodynamic equation of state parameters investigations of high-density polyethylene modified by aluminium hydroxide and other supporting agents were presented in the article. The dependences of polyethylene modification on changes of specific volume of polyethylene in the function of temperature and pressure, crystallization kinetics and Tait.s thermodynamic equation parameters were established.

11

Heat Transfer Model For Marine Two Stroke Engine Cylinder

Kowalski J., Tarełko W.

Journal of Polish CIMAC

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2007

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Vol. 2, no 1

273-280

EN

This paper deals with modeling of heat flow through cylinder structural components of a marine two-stroke engine. Especially, we paid attention on simulating of temperature distribution for the wet cylinder liner. Multidimensional equations for the transient heat conduction with the Dirichlet and Fourier boundary conditions have been applied. In particular, we applied local values for the convective and radiative heat transfer coefficients using the Fourier boundary conditions determined in a space of cylinder volume and a cooling space of the cylinder. In order to determine the temperature distribution for considered spaces, we applied the radiosity method. Simulation results have been presented in the form of a temperature field for cylinder structural components depended on the crankshaft position angle. Application of the iterative calculation method for solving differential equations of energy balance allowed us for using software easy to get. We carried out all iterative computations using MS Excel spreadsheet. This way, we could decrease the simulation cost significantly.

12

The thermal state modelling of cylinder liner of marine two-stroke combustion engine

Kowalski J., Tarełko W.

Polish Maritime Research

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2006

|

nr 2

15-20

EN

This paper presents a two-dimensional model of heat flow through structural elements of cylinder of two-stroke cross-head engine of longitudinal scavenging, obtained with the use of the elementary balance method. Special attention was paid to the modelling of temperature distribution within engine cylinder liner of "wet" construction. For modelling the unsteady heat flow multi-dimensional equations with Dirichlet - Fourier boundary conditions, were used. For the Fourier boundary conditions in the engine cylinder space local values of convective and radiant heat-transfer coefficients were applied. For calculations the KM3R method of solving differential equations, based on the elementary balance method, was used. Modelling results have been presented in the form of the temperature field of engine cylinder structural elements in function of the changeable angle of crankshaft position.

13

Application of Radiosity Method to Modelling Cylinder Liner Thermal State of Marine Engines

Tarełko S., Kowalski J., Nowaliński S.

Machine Dynamics Problems

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2006

|

Vol. 30, No. 4

160-170

EN

To increase the piston engine effectiveness, we should recognize the heat-releasing phenomenon from an engine cylinder volume. Such knowledge should allow us to model and determine the thermal stresses in the individual structural components of a cylinder liner. Having, in turn, information concerning the distribution of the thermal stresses in these components, we could design an appropriate layout of cooling system elements such as cooling curves, rates, surfaces, etc. This paper deals with the modelling of heat flow through cylinder liner structural components of a two-stroke engine. Especially, we paid attention to simulating temperature distribution for the wet cylinder liner. Multidimensional equations for the transient heat conduction with the Dirichlet and Fourier boundary conditions have been applied. In particularly, we applied local values for the convective and radiative heat transfer coefficients using the Fourier boundary conditions determined in space of cylinder volume. In order to determine the temperature distribution for the considered space, we applied the radiosity method. Simulation results have been presented in the form of a temperature field for cylinder liner structural components depending on the crankshaft position angle. Application of the iterative calculation method for solving differential equations of energy balance allowed us to use software easy to get. We carried out all iterative computations using Excel spreadsheet. This way, we could decrease the simulation cost significantly.

14

Porównanie warunków klimatycznych i bioklimatycznych północnej części Ziemi Oscara II z innymi obszarami zachodniego wybrzeża Spitsbergenu w okresie 1875-2000

Przybylak R., Araźny A.

Problemy Klimatologii Polarnej

|

2005

|

nr 15

119-131

PL

W artykule porównano warunki klimatyczne i bioklimatyczne N części Ziemi Oskara II z innymi obszarami zachodniego wybrzeża Spitsbergenu w okresie 1975-2000. Klimat Ziemi Oskara II przedstawiono na podstawie danych meteorologicznych ze stacji Ny Alesund. Klimat centralnej i południowej części zachodniego wybrzeża Spitsbergenu reprezentują odpowiednio stacje: Svalbard-Lufthavn i Hornsund. Dla wymienionych obszarów obliczono i przeanalizowano różnice pomiędzy średnimi miesięcznymi i rocznymi wartościami wybranych elementów meteorologicznych (wiatr, zachmurzenie, temperatura i wilgotność powietrza oraz opady atmosferyczne) i wskaźników biometeorologicznych (niedosyt fizjologiczny, wielkość ochładzająca powietrza, wskaźnik ochładzania wiatrem, temperatura ochładzania wiatrem, przewidywana izolacyjność odzieży).

EN

The paper describes the climate and bioclimate of the tundra zone in the northern part of Oscar II Land (the area from Jonsfiorden to Kongsfiorden) from 1975 to 2000. A comparison with the climate and bioclimate of other parts of the west coast of Spitsbergen is also presented. For the analysis, meteorological data from three stations (Ny Alesund, Svalbard Lufthavn and Hornsund) were used (Fig. 1). Significant differentiation of climatic conditions on the west coast of Spitsbergen was found (Table 1 and Fig. 2). Wind direction and speed was strongly modified by the local topographic conditions. For this reason, the lowest mean annual wind speed (by 1.2 to 1.7 m/s) of the three analysed stations, was in Ny Alesund. The degree of cloudiness was similar at Ny Alesund and Svalbard Lufthavn, while at Hornsund it was greater by about 6%. Mean annual air temperature at Ny Alesund is slightly higher (by 0.1°C) than at Svalbard Lufthavn and significantly lower (by 1.1°C) than at Hornsund. In the annual course, in comparison with the central part of the west coast, the northern part of Oscar II Land is markedly warmer in winter (on average by 1.0°C) and significantly colder in summer (by 1.0°C). An opposite relationship may be noted when comparison is made with the southern part of Spitsbergen. The greatest values of relative humidity occur in the southern and northern parts of Spitsbergen, while in the central part of the western coast their values are smaller (in particular in summer). Atmospheric precipitation was twice as low in the central part of the western coast of Spitsbergen as it was in its northern and southern parts. Differences in bioclimatic conditions were found on the west coast of Spitsbergen (Table 2, Fig. 3). To establish their characteristics, a number of biometeorological and thermophysiological indices were used. These enabled the estimation of the sensations of heat in humans standing outdoors in this part of Spitsbergen. Analysis of the physiological deficit (D) values on the west coast of Spitsbergen indicate that water evaporation from the human upper respiratory tract during the whole year is high. The cooling power (H) shows significant differences between different parts of western Spitsbergen. The mean number of days per year with thermal comfort for humans oscillated between 11 at Svalbard Lufthavn and 18 at Hornsund to 42 at Ny Alesund. On the other hand, days with cold discomfort were most frequent in central (277) and southern (271) parts of Spitsbergen, while in the northern part they rarely occurred (only 217). The best thermal sensations (described as 'cool') according to the wind chill index (WCI) occur from June to September at all stations, and also in May at Ny Alesund. In the other months conditions described as 'cold' were noted over the entire area. Days with a possibility of frostbite were noted with an annual average frequency of about 10 at Ny Alesund and 25 at Svalbard Lufthavn and Hornsund. The wind chill temperature (WCT) throughout the west coast of Spitsbergen shows the dominance of moderate sensations of cold from November to April. During the summer months (July and August) sensations of 'cold' did not occur. The insulation predicted index (Iclp) was used to estimate the bioclimate of Spitsbergen from the point of view of an individual's need for clothes to obtain thermal comfort. The index was calculated for a standing man and a man who is walking at a speed of 4km/h. Its values for the standing individual oscillated from 4.35 clo at Hornsund to about 4.49 clo at Svalbard Lufthavn. On the other hand, for the walker, clothes would need half the thermal insulation level to obtain thermal comfort.

15

Układ do kontroli stanów cieplno-wytrzymałościowych wirników na podstawie pomiaru temperatury metalu.

Kurowicz M.

Zagadnienia Eksploatacji Maszyn

|

2004

|

Vol. 39, nr 3

145-161

PL

Przedmiotem rozważań jest element metody kontroli stanu cieplno-wytrzymałościowego wirnika turbiny podczas rozruchu, zmiany mocy oraz w stanie nominalnego obciążenia. Punktem wyjścia do modelowania rozkładów temperatury, obciążeń cieplnych i naprężeń są wyniki bezpośredniego pomiaru temperatury metalu w wybranych miejscach wirnika. W pracy przedstawiono zasadę pomiaru temperatury metalu w wybranych miejscach wirnika turbiny oraz koncepcję i założenia projektowe układu pomiarowego. Opisano sposób mocowania czujników pomiarowych oraz dwa rozwiązania transmitera (układu przeniesienia sygnału z wirującego wirnika). Przedstawiono również przebieg i wyniki badań tych układów w warunkach laboratoryjnych. Przykładowo podano wyniki pomiarów temperatury uzyskane w rzeczywistych warunkach stygnięcia wirnika WP turbiny 13K215.

EN

The assessment of thermal states is based on the temperature measurements in chosen locations of an investigated component. These measurements are complemented with the measurements of the fluid flowing around the component surface. This approach is commonly applied to the control and diagnostic systems of power units (boilers and turbines) for the assessment of thermal states of non-rotating thick-walled components (boiler drums, casings, valves chamber and clamping rings). There is however different situation as far as rotors are concerned. Direct control of their thermal state during standard operation is somewhat more difficult. This is because temperature distribution in rotating coordinates has to be determined. Such situation forces indirect control of thermal states. The simplest approach bases only on the rate of changes of livesteam temperature. Standard control systems usually apply a restriction (maximal value) for the rate of changes of livesteam temperature. This restriction is meant to protect the rotor from high stresses. This paper presents on-line system for the assessment of operating conditions of rotors. It involves direct method. The investigations of thermal state derive from the measurements of the rotor temperature in its several locations. The article presents the idea of measurements of rotor temperature in several chosen locations. The assumptions made for the construction of the measurements set are described. The construction of the handle is shown, which allows to attach thermoelements to a turbine rotor. Two alternative designs of the transmitter are presented, which allow to carry the measurement signal out of the rotor. The main assumptions for the design of the on-line control of thermal and strength states are as follows: - rotor temperature is measured in the central void of the rotor; - the number of measurement locations in the rotor is arbitrary; practical application assumes four measurements; - the measurement of the temperature utilizes standard Pt100 thermocouple, which is commonly used in power units diagnostics; - the measurement signal is carried out of the rotor from the thermocouple to the measurement set through a transmitter installed at the end of the rotor. The electronic part of the measurement set was designed and assembled. It was then tested at the laboratory. Experimental tests were also conducted at the operating steam turbine. The set measured the rotor temperature of the high pressure part of a steam turbine. Analysis was done during a cool-down after the first operating period of just repaired turbine. The tests proved that practical application of the presented approach requires temperature measurements in 1-4 locations and current intensity transmission of measurement signal.

16

Symulacja zmian stanu cieplno-wilgotnościowego przegród ze styropianem

Grabarczyk S.

Warstwy, Dachy i Ściany

|

2004

|

nr 2

25-27

17

Badania przekładni planetarnych układów napędpwych przenosników górniczych

Spałek J., Skoć A.

Tribologia

|

2001

|

nr 4

773-781

PL

W opracowaniu przedstawiono wyniki analizy konstrukcyjnej oraz badań stanowiskowych prototypów wysokomomentowych przekładni planetarnych, przeznaczonych do napędów przenośników górniczych o dużej wydajności transportowej. Wykazano, że nowe przekładnie zaprojektowane i wyprodukowane w kraju mogą z powodzeniem znaleźć zastosowanie w praktyce górniczej.

EN

The work presents findings of construction analysis and stand tests of high-momentum planetary gears prototypes designed for heavy-duty mine conveyers drives. It is shown that new gears, designed and produced in Poland can be successfully applied in mining.