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1

Investigations of rheological and tribological properties of some synovial fluids substitutes

Grykin Monika, Klekotko Marcin, Dąbrowski Jan R.

Engineering of Biomaterials

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2021

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Vol. 24, no. 163

67

EN

Ensuring adequate lubrication in the synovial joint is extremely important for the proper functioning of the locomotor system. Low movement resistance and favorable viscoelastic characteristics are features that define a healthy joint. Natural biomolecules – present in the synovial fluid – are responsible for the lubrication of the articular surfaces. When they are degraded, due to disease or injury, the joint becomes dysfunctional. In such cases, the most common medical procedure is the administration of a series of injections in order to deliver the biolubricant into the joint’s space. The preparations that are substitutes for synovial fluid should be characterized by high biocompatibility as well as the appropriate rheological and tribological properties. In this paper, the basic compositions of the artificial synovial fluid were tested. They consisted of lowmolecular polyacrylamide, high-molecular polyacrylamide and hyaluronic acid sodium salt. For the comparative purposes, the commercial preparation named Hyalgan, which is used in viscosupplementation treatments, was also tested. During the experimental research, physicochemical measurements were carried out, such as the measurement of the pH value, electrolytic conductivity and surface tension. In order to determine the properties of the viscoelastic substitutes, rheological tests were carried out with the use of a rotational rheometer. To determine the resistance to motion, friction tests were carried out for reciprocating motion. Additionally, energy dissipation was estimated, and microscopic analysis of friction traces was performed. This gave a possibility to determine the volume of friction traces and to compare the influence of the tested lubricants on the wear intensity of the samples. The obtained test results indicate that preparations based on polyacrylamide have a beneficial effect on lowering the resistance to motion in the tested tribological systems. They are also characterized by advantageous viscoelastic properties. It is worth noting that among all the tested synthetic synovial liquid compositions, the preparation based on high molecular weight polyacrylamide showed the most promising functional properties.

2

Transient Heat Flow in a One-component Lennard-Jones/spline Fluid : a Non-equilibrium Molecular Dynamics Study

Hafskjold B.

Computational Methods in Science and Technology

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2017

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Vol. 23, No. 3

185--198

EN

A one-component Lennard-Jones/spline fluid at equilibrium was perturbed by a sudden change of the temperature at one of the system’s boundaries. The system’s response was determined by non-equilibrium molecular dynamics (NEMD). The results show that heat was transported by two mechanisms: (1) Heat diffusion and conduction, and (2) energy dissipation associated with the propagation of a pressure (shock) wave. These two processes occur at different time scales, which makes it possible to separate them in one single NEMD run. The system was studied in gas, liquid, and supercritical states with various forms and strengths of the thermal perturbation. Near the heat source, heat was transported according to the transient heat equation. In addition, there was a much faster heat transport, correlated with a pressure wave. This second mechanism was similar to the thermo-mechanical “piston effect” in near-critical fluids and could not be explained by the Joule-Thomson effect. For strong perturbations, the pressure wave travelled faster than the speed of sound, turning it into a shock wave. The system’s local measurable heat flux was found to be consistent with Fourier’s law near the heat source, but not in the wake of the shock. The NEMD results were, however, consistent with the Cattaneo-Vernotte model. The system was found to be in local equilibrium in the transient phase, even with very strong perturbations, except for a low-density gas. For dense systems, we did not find that the local equilibrium assumption used in classical irreversible thermodynamics is inconsistent with the Cattaneo-Vernotte model.

3

One-Dimensional Unsteady Flow : a New Presentation of the Issue

Dowkontt S., Dowkontt G. A.

Machine Dynamics Research

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2015

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Vol. 39, No. 4

31-41

EN

The subject of the article is a one-dimensional unsteady flow. The authors introduce ζ , a new function which expresses the position of liquid planes in the flow relative to the positions they occupied when the fluid was at rest. This enabled the replacement of two partial differential equations of the first order included in the system of equations describing one-dimensional unsteady flow by a partial differential equation of the second order for function ζ .

4

Ervironmental friendly drilling fluid management offshore Norway

Bilstad T., Jensen B., Toft M.

AGH Drilling, Oil, Gas

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2014

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Vol. 31, no. 2

191--197

EN

Types and amount of fluids utilized when drilling a well determine to which extent the drilled cuttings are legally considered hazardous waste. The main categories of drilling fluids are oil based (OBM), water based (WBM) and synthetic based mud (SBM). The purpose of adding fluids to the drilling operations is to cool and lubricate the drill bit, to stabilize the well bore, to control subsurface pressure, to control formation pressure, to control well stability. to control corrosion, and to carry cuttings to the surface. Historically, cuttings from drilling sub-surface wells have been depositeddirectly from the platform to the seabed. However, environmental laws and regulations for the Norwegian offshore sector prohibit such practice when the oil on cutting exceeds 1 % by weight. Re-injection of cuttings as a slurry into subsurface formations is still practiced. Due to migration, leaks, re-entering of slurry onto the seabed, and collapsing formations this disposal method is on a decline. Transport of oily cuttings to shore for final treatment is the preferred Norwegian practice. However, cutting treatment on platforms is also continuousl yevaluated. For logistics and cost reasons, as well as health, safety and environmental (HSE) and working environment reasons, emphasis is put on offshore waste minimization, reuse and recycle.Ten onshore locations in Norway are currently receiving cuttings for further treatment and fluid recovery. The treated cuttings are for the most part disposed in landfills.

5

Offshore drilled cuttings management

Bilstad T., Stenberg E. S., Jensen B., Larsen T., Toft M.

AGH Drilling, Oil, Gas

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2013

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Vol. 30, no. 1

47--50

EN

The search for offshore fossil fuels generates large volumes of drilled cuttings which under certain conditions are defined hazardous, negating disposal at sea. Much of the cuttings end up in onshore landfills. The types of fluids used in well drilling operations determine to which extent the cuttings are considered hazardous. The three main types of fluids are oil based mud (OBM), water based mud (WBM) and synthetic based mud (SBM). The purpose of adding fluids or mud in the drilling operations is to cool and lubricate the drill bit, to stabilize the well bore, to control subsurface pressure, formation pressure, well stability and corrosion, and to carry cuttings to the surface. OBM is based on either diesel or mineral oil. One advantage of OBM is enhanced drilling performance, especially in technical challenging environments. A drawback, however, is the toxicity of OBM, prohibiting discharge of cuttings to the marine environment. Drilled cuttings are rocks produced during drilling operations, becoming coated with drilling fluids. Historically, cuttings have been disposed to sea. However, recent environmental laws and regulations prohibit such practice. Re-injection of cuttings as a slurry into subsurface formations has also been discontinued due to leaks and re-entering of slurry into the bottom waters. Transport of cuttings to shore is therefore the choice. For logistics and cost reasons emphasis is put on offshore waste minimization and reuse/recycle. Total fluid management (TFM) leads to environmental impact reduction (EIR). Minimization of drilling fluids and reuse of fluids lead to cost reduction. Volume of cuttings is reduced through directional drilling and by drilling smaller diameter holes. Synthetic based drilling fluids (SBM) are replacing OBM. Drilling wastes are further separated into a fluid and a solid phase. The solids may be used for road and other construction purposes, whereas the OBM is burned for energy recovery. The purpose of the thermo-mechanical cuttings cleaner (TCC) is to convert hazardous oily cuttings into useful products. TCC facilities are only available onshore in Norway. However, offshore TCC units will in due time be introduced, negating the need for transport of cuttings to shore. Cuttings are allowed disposed to sea when no toxic fluids are attached. TCC separation is accomplished by generating temperatures of 240-300 degrees of Celsius sufficient for evaporation of oil and water from the mineral solids.

6

Influence of Rheological Size Parameters on Yarn Properties

Kovacevic S., Mijovic B., Grancaric A. M.

Fibres & Textiles in Eastern Europe

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2012

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Vol. 20, no. 4 (93)

41--46

EN

The paper describes the results of changed size viscosity as a function of the temperature, concentration and shear stress. The rheological properties of size with various concentrations in combination with components of synthetic sizing agents based on polyvinyl alcohol (PVA) and carboxymethyl cellulose (CMC) were investigated. The size viscosity increased with decreasing temperatures and the increasing spindle speed of the viscometer. The breaking force and abrasion resistance of yarn sized under different rheological conditions by changing the temperature of sizing were examined. Measurement results show that by changing the size temperature from 50 °C to 80 °C the breaking force of the yarn mostly increased too. A change in the size temperature affects the yarn abrasion resistance, but these changes do not follow the linearity of the breaking force either, which is expressed by a comparison of the synthetic sizing agents with the same concentrations.

PL

W artykule przedstawiono zmiany lepkości preparacji, w wyniku zmian temperatury, stężenia i szybkości ścinania. Badano preparacje składające się z alkoholu poliwinylowego (PVA) i karboksymetylocelulozy (CMC). Mierzono wytrzymałość przędzy na rozciąganie oraz odporność na ścieranie. Przy wzroście temperatury z 50 °C do 80 °C stwierdzono, że wzrosła również wytrzymałość przędzy. Uzyskane wyniki poddano wnikliwej analizie.

7

Wrzenie na poziomym pęku rur gładkich i z powłoką porowatą. Część 2

Krasowski K., Cieśliński J.

Technika Chłodnicza i Klimatyzacyjna

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2011

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nr 2

60-72

PL

Druga część artykułu poświęconego problematyce badań doświadczalnych procesu wrzenia wybranych cieczy roboczych na poziomym pęku rur gładkich i rur z powłoką porowatą. W jego części pierwszej („TCHK”, nr 1/2011, s. 5) podano parametry opisujące proces wrzenia na poziomym pęku rur, a następnie dokonano przeglądu wybranych wyników badań eksperymentalnych wielu autorów, dotyczących procesu wrzenia na pęku rur gładkich, rur o powierzchni rozwiniętej i rur pokrytych powłoką porowatą. Przedstawiono również zagadnienie modelowania wrzenia na pęku rur. Część druga artykułu zawiera opis stanowiska badawczego i zastosowanej metodyki opracowania wyników pomiarów. Zaprezentowano uzyskane wyniki badań doświadczalnych prowadzonych przez autorów wraz z opracowanymi na ich podstawie korelacjami

EN

This is the second part of paper dealing with experimental investigations of pool boiling of selected fluids on horizontal bundles of plain tubes and porous coated tubes. In the first part ("TCHK", nr 1/2011, s. 5) the parameters of pool boiling on horizontal tube bundle have defines and selected published results of boiling tests on bundles of plain, enhanced and porous coated tubes have been presented. Models of pool boiling on horizontal tube bundle have been discussed. In the second part the test stand and investigation procesure are described. Original test results and own correlations are given

8

Cutting fluids and their influence on cutting process

Cillikova M., Micietova A., Salaj J.

International Journal of Applied Mechanics and Engineering

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2010

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Vol. 15, no 2

457-461

EN

The paper deals with the influence of a cutting fluid on the cutting force and machined surface when turning steel 12050. Cutting fluids, Emulzín H, RO 32 were applied in the experiments. Some of the experiments were performed without a coolant.

9

Ciecze do likwidacji odwiertów

Uliasz M.

Nafta-Gaz

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2007

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R. 63, nr 4

223-231

PL

W artykule przedstawiono wyniki badań laboratoryjnych dotyczące opracowania składów cieczy do likwidacji odwiertów, w oparciu o materiały i środki chemiczne spełniające określone wymagania górnicze i ochrony środowiska.

EN

This paper presents results of the laboratory research carried out on the well liquids compositions used to plug and abandonment well. The tested compositions full fielled the mining and ecological standards.

10

Topology optimization - broadening the areas of application

Bendsoe M. P., Lund E., Olhoff N., Sigmund O.

Control and Cybernetics

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2005

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Vol. 34, no 1

7-35

EN

This paper deals with recent, developments of topology optimization techniques for application in some new types of design problems. The emphasis is on recent work of the Danish research groups at Aalborg University and at the Technical University of Denmark and focus is on the central role that the choice of objective functions and design parameterization plays for a successful extension of the material distribution approach to new design settings and to new types of physics models. The applications that will be outlined encompass design of laminated composite structures, design for pressure loads, design in fluids, design in acoustics, and design in photonics. A short outline of other design optimization activities is also given.

11

Ruin marble : a record of fracture-controlled fluid flow and precipitation

Marko F., Pivko D., Hurai V.

Geological Quarterly

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2003

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Vol. 47, No 3

241-252

EN

The ruin marble structure of the Cretaceous/Paleogene fine-grained marly limestone from the Outer Flysch Belt of the Western Carpathians has a non-tectonic origin, according to structural and sedimentological evidence. Distinctive offsets of coloured red-brownish ferric oxyhydroxide bands are not due to displacements along rock-cutting fractures, as they superficially appear to be. Evidences for shear movement along these pseudo-faults were not observed. Band offsets result from different velocities of pervasively diffusing fluids, precipitating ferric oxyhydroxides in corridors bounded by sets of mineralised systematic joints. During rock weathering, calcite-filled joints operated as barriers for lateral fluid diffusion, but enabled longitudinal diffusion along healed joints. Simple laboratory experiments have been performed to simulate the formation of natural ruin marble structure.

12

On thermal convection in micropolar fluids in presence of suspended particles

Mohan H., Kumar P., Anjula

Studia Geotechnica et Mechanica

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2002

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Vol. 24, nr 3-4

53--63

PL

Opisano niestabilność termiczną płynów mikropolamych w obecności cząstek zawieszonych. Sprzężenie między ruchem wirowym a strumieniami ciepła może być przyczyną nadstabilnych stanów w układzie. Zawieszone cząstki wprowadzają także drgania w układzie, a wartość liczby Rayleigha zmniejsza się ze zwiększeniem liczby cząstek zawieszonych.

EN

The thermal instability of micropolar fluids in the presence of suspended particles has been considered. The coupling between spin and heat fluxes may bring overstable modes in the system. The suspended particles also introduce oscillatory modes in the system and the Rayleigh number is found to decrease with the increase in suspended particles.

13

Działalność i osiągnięcia Polskiego Serwisu Płynów Wiertniczych Sp. z o.o. w Krośnie

Dudek A., Pudło J.

Prace Instytutu Górnictwa Naftowego i Gazownictwa

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2002

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nr 116 wyd. konferencyjne

347--350

14

The instability of streaming Rivlin-Ericksen fluids in porous medium

Sharma V., Kishor K., Rana G.

Studia Geotechnica et Mechanica

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2001

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Vol. 23, nr 3-4

83--93

PL

Badano niestabilność przepływu cieczy Rivlina-Ericksena w ośrodku porowatym. Przyjęto, że ich konfiguracja jest denna. Stwierdzono, że jeśli nie było napięcia powierzchniowego, to przepływ nie wpływał na zaburzenia poprzeczne do jego kierunku pod warunkiem, że zaniedbano zaburzenia w kierunku przepływu, podczas gdy w przypadku zaburzeń we wszystkich innych kierunkach stwierdzono niestabilność dla pewnego zakresu liczby falowej. Napięcie powierzchniowe może tłumić tę niestabilność Kelvina-Helmholtza w przypadku niewielkich zaburzeń długości fali, a porowatość i lepko-sprężystość ośrodka zmniejsza zakres stabilności w odniesieniu do różnicy w szybkościach przepływu. Napięcie powierzchniowe stabilizuje pewien zakres liczby falowej dla powierzchniowej konfiguracji.

EN

The instability of streaming Rivlin-Ericksen fluids in porous medium is considered. The configuration is taken to be bottom-heavy. In the absence of surface tension, the perturbations transverse to the direction of streaming are found to be unaffected by the presence of streaming if perturbations in the direction of streaming are ignored, whereas for perturbations in all other directions, there exists the instability for a certain wave number range. The surface tension is able to suppress this Kelvin-Helmoltz instability for smali wave length perturbations, and the medium porosity and the viscoelasticity reduce the stability rangę given in terms of a difference in streaming velocities. For the top heavy configurations, the surface tension stabilizes a certain wave number range.

15

Altenberger A., Dahler J.S.

Polish Journal of Chemistry

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2001

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Vol. 75, nr 4

601-616

EN

An approach based on the concept of functional self-similarity is used to derive equations of state for two- and three-dimensional hard-particle fluids. Calculations indicate that this procedure works quite well, producing estimates of the compressibility factor that closely agree with the results of computer simulation.

16

Freezing Behavior in Porous Materials : Theory and Experiment

Śliwińska-Bartkowiak M., Dudziak G., Sikorski R., Gras R., Gubbins K. E., Radhakrishnan R., Kaneko K.

Polish Journal of Chemistry

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2001

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Vol. 75, nr 4

547-555

EN

We report both experimental measurements and molecular simulations of the melting and freezing behavior of simple fluids in porous media. Activated carbon fibers, having a mean pore width of 1.7 nm, were chosen as the porous medium. Differential scanning calorimetry (DSC) and dielectric relaxation spectroscopy (DS) were used to determine the melting point in these materials. The melting point was found to be very sensitive to the relative strength of the fluid-wall interaction compared to the fluid-fluid interaction. Monte Carlo simulations and Landau free energy formalism were used to determine the shift in the melting point, Tm, for simple fluids in pores having repulsive, weakly attractive and strongly attractive walls. The strength of the interaction of the fluid with the pore wall is shown to have a large effect on the shift in Tm, with Tm being reduced for weakly attracting walls. The theory of corresponding states is used to compare the experimental results for several systems to the simulation results. This approach also provides a unified approach in understanding the diverse freezing behavior in porous media.

17

Badania inkluzji fluidalnych w spoiwie kwarcowym piaskowców kambru środkowego na obszarze bloku Łeby w Morzu Bałtyckim - implikacje diagenetyczne, izotopowe i geochemiczne

Jarmołowicz-Szulc K.

Biuletyn Państwowego Instytutu Geologicznego

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2001

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nr 399

1-84

PL

W spoiwach kwarcowych piaskowców środkowego kambru z otworów wiertniczych wykonanych na obszarze bloku Łeby (tzw. blok B) polskiej części Morza Bałtyckiego stwierdzono występowanie dwóch typów inkluzji fluidalnych - wodnych i węglowodorowych. Ich tworzenie jest związane z migracją mieszanych fluidów i uwięzieniem ich we wczesnym i późnym cemencie. Inkluzje mają rozmiary od 1do 10mim i charakteryzują się zróżnicowanym świeceniem w nadfiolecie. Inkluzje roztworów wodnych nie wykazują fluorescencji, podczas gdy inkluzje węglowodorowe świecą w barwach od niebiesko-białej do żółtej. Ropa naftowa w inkluzjach jest dojrzała, jej gęstość wynosi pomiędzy 41 a 45 stopni API. Inkluzje wodne znajdują się na granicy ziarna kwarcu detrytycznego i autigenicznego, we wczesnym cemencie i w późnych zabliźnieniach mikroszczelin. Inkluzje węglowodorowe są najczęstsze w późnych wypełnieniach szczelin. Temperatury homogenizacji dla inkluzji ropy naftowej mieszczą się w przedziale maksimum częstości 60-93 stopni Celsjusza. Z badań punktowych składu izotopowego kwarcu wynika zmienność wartości rho18O w zakresie od 19,4 do 25,6o/ooSMOW dla wczesnego cementu kwarcowego. Wartość rho18O wód porowych mieści się w zakresie pomiędzy (-11) a (-5)o/ooSMOW, średnio (-7,5)o/ooSMOW, przyjmując temperaturę 50 stopni Celsjusza inkluzji jednofazowych jako minimalną wartość temperatury uwięzienia inkluzji we wczesnym spoiwie.

EN

Two types of fluid inclusions - aqueous and hydrocarbon - have been stated in quartz cements in the Middle Cambrian sandstones from the Łeba block (so called block B) in the Polish part of the Baltic Sea. Their formation is connected with fluid migration and trapping in the quartz cements - early and late. Inclusions are of 1 to 10 mim in size and display different fluorescence features in the ultraviolet light. Aqueous inclusions do not fluoresce, while those hydrocarbon ones show luminescence in colours from blue-white to yellow. The petroleum in inclusions is mature, its density oscillates between 41 and 45 degrees of API. The aqueous inclusions are at the boudary od detrital and authigenic quartz, in the early cement and in late filling of microfractures. The hydrocarbon inclusions are most frequent in the late filling of the fissures. Homogenisation temperatures for petroleum inclusions are in the maximum frequency interval of 60-93 degrees of Celsius. It results from the point oxygen isotope studies in quartz that rho18O values oscillate between 19.4 and 25.6o/ooSMOW for the early cement. The rho18O composition of pore waters lies in the interval of (-11) to (-5)o/ooSMOW, in average (-7.5)o/oo SMOW, when adopting a temperature of 5 degrees of Celsius from one phase inclusions as the minimum of trapping of the inclusions in the early cement.

18

A Note on radiation conditions for narrow-band random waves generated in fluid of constant depth

Szmidt J. K.

Archives of Hydro-Engineering and Environmental Mechanics

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2001

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Vol. 48, nr 4

39-55

EN

In the paper, the generation of narrow-band random waves in a semi-infinite layer of fluid is considered. The problem is formulated in a discrete space of chosen points by means of the finite difference method. The main goal of the investigations is to construct radiation boundary conditions which enable us to replace the infinite fluid area with a finite domain. The investigations are illustrated with experimental results and numerical examples confirming efficiency of the discrete model developed in the paper.

19

Gacek Z., Maźniewski K.

Nukleonika

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1999

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Vol. 44, nr 2

341-348

EN

Basic electrokinetic processes in some fluids during their forced transportation are considered. Based on the similar mathematical equations for the transport of ionic species, the way how to estimate electrification intensity has been proposed. The methods used to investigate electrification effects of the media under consideration are analysed.

PL

Przedmiotem rozważań są procesy elektryzacyjne niektórych płynów (cieczy i gazów), będące skutkami skomplikowanych zjawisk fizykochemicznych zachodzących podczas wymuszonego przemieszczania mediów przez rurociągi metalowe lub elementy instalacji o podobnym charakterze. Szczególną uwagę poświęcono podobieństwom i różnicom powyższych procesów, a następnie - zakładając określone uwarunkowania - zaproponowano ich jednolity opis pod względem jakościowym i ilościowym. Ponadto omówiono niektóre metody badania efektów elektryzowania się praktycznie nieprzewodzących cieczy i gazów zawierających cząstki stałe.

20

On the solubility of chain alcohols in supercritical carbon dioxide

Gregorowicz J., Chyliński K.

Polish Journal of Chemistry

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1998

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Vol. 72, nr 5

877-885

EN

The phase behaviour in the CO2-n-alkanol family was presented and its influence on the solubility measurements was discussed. A linear relationship is suggested between the logarithm of solubility of liquid n-alkanols in supercritical CO2 and the carbon number of the solute. The hypothesis based on experimental data is supported by thermodynamic considerations. Solubilities of 1-hexanol at 311 K and 1-decanol at 313 K were measured in order to extend the group substances studied in this paper.