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1

45 Years of Deliberations on the Thermo-Mechanical Interpretation of Friction and Wear. Part I. The Macroscopic Interpretation of the Tribological Process

Sadowski Jan

Tribologia

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2022

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nr 2

55--66

EN

This first part will consider the friction couple or its part, identified with the open thermodynamic system. Dependences among extensive parameters and energetic interactions in the system and its boundaries with the environment are described in analytical terms. The dimensions of the energy dissipation zone, where the friction of solids takes place, are established. The thermo-mechanical nature of the tribological process is demonstrated. The wear conditions and distribution of energy generated by its particular elements are determined. A new quantity is introduced – the specific work of wear, which characterises the wear resistance of the tribological system and its parts. The effect of the reciprocal cover of solids’ friction surfaces on the energy balance structure in calorimetric testing is analysed. The concept of generalised wear is introduced and standardised. The discussion is restricted to processes at the macroscopic level of matter organisation.

PL

Przedmiotem rozważań w pierwszej części pracy jest para tarciowa lub jej fragment utożsamiona z systemem termodynamicznym otwartym. Opisano analitycznie zależności między parametrami ekstensywnymi i oddziaływaniami energetycznymi w systemie i na jego graniach z otoczeniem. Ustalono wymiary strefy dyssypacji energii, w której zachodzi tarcie ciał stałych. Wykazano cieplno-mechaniczną naturę procesu tribologicznego. Ustalono warunki zachodzenia zużywania i rozdziału energii rozproszonej przez poszczególne jego elementy. Wprowadzono nową wielkość – pracę właściwą zużycia, charakteryzującą odporność na zużywanie systemu tribologicznego i jego elementów. Zanalizowano wpływ wzajemnego przykrycia powierzchni tarcia ciał na strukturę bilansu energii w badaniach kalorymetrycznych. Wprowadzono pojęcie zużycia uogólnionego i jego standaryzację. Rozważania ograniczono do procesów zachodzących na makroskopowym poziomie hierarchicznym organizacji materii.

2

Instalacje gazów medycznych, sprężonego powietrza i próżni. Część 1. Podstawy termodynamiki gazów

Kaiser K.

Technika Chłodnicza i Klimatyzacyjna

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2017

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nr 5

170--175

PL

Sprężone gazy i pary znajdują szerokie zastosowanie w różnych gałęziach przemysłu, m. in. w przemyśle spożywczym, chłodnictwie i transporcie. Do najczęściej sprężanych płynów można zaliczyć np.: powietrze, czynniki chłodnicze, amoniak, azot, tlen, dwutlenek węgla, hel, argon, metan. Ze względu na wymagane parametry w zależności od przeznaczenia sprężane gazy dzieli się na: gazy techniczne, medyczne i spożywcze. W prezentowanym cyklu artykułów znajdą się m. in. niezbędne w codziennej eksploatacji informacje z termodynamiki gazów, wymiany ciepła, działania urządzeń i instalacji gazów medycznych, obsługi tych instalacji oraz obsługi butli gazowych. Ponadto znajdą się w nim również informacje dotyczące wykonania tych instalacji i bezpieczeństwa ich użytkowania.

EN

Compressed gases and vapours are widely used in many branches of industry, such as food processing, refrigeration and transport. The most common compressed media are: air, refrigerants, ammonia, nitrogen, oxygen, carbon dioxide, helium, argon, methane. Taking into account desired parameters and application area, technical, medical and food processing compressed gases can be distinguished. The series of papers deals - except others - with necessary from the practical point of view information on thermodynamics of gases, heat transfer, working principles of devices and installations for medical gases, as well as operation of these installations and gas cylinders. Manufacturing technologies and safety aspects are also described.

3

Impact Characteristic According to the Structure of Crash Box at the Vehicle

Min B. S., Cho J. U.

Archives of Metallurgy and Materials

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2017

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Vol. 62, iss. 2B

1047--1050

EN

The crash box between a bumper and a car body in automobiles can reduce impacts for car bodies with a bumper at a low-speed collision by preventing the shocks. Also, this crash box is the part playing a very important role for the safety of vehicle and the reduction of repair cost, and many studies have been investigated for the performance. In this study, aluminum foam was inserted in an aluminum crash box to analyze the relationships of deformation, stress and internal energy. The compression characteristics are compared with six cases. In addition, the load due to displacement at experiment for a case is verified by modeling with finite elements and performing the structural analysis. As these study results for investigating characteristics of the crash box, it is thought that the effective designs of crash box to enhance the durability for collision are made possible.

4

Właściwości gazów doskonałych i półdoskonałych

Litke B.

Problemy Nauk Stosowanych

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2016

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T. 4

95--106

PL

Wstęp i cele: W pracy przedstawiono pojęcie gazu doskonałego i półdoskonałego. Podano prawa Boyle’a-Mariotte’a, Gay Lussaca-Charlesa, Avogadra. Pokazano równania stanu gazu doskonałego. Omówiono ciepło właściwe, energię wewnętrzną i entalpię dla gazów doskonałych i półdoskonałych. Przedstawiono pojęcie mieszaniny gazów doskonałych i półdoskonałych. Podano prawo Daltona i Leduca. Opisano udział masowy kilogramowy, molowy i objętościowy oraz ciśnienie cząstkowe, stałą gazową mieszaniny gazów, gęstość i masę molową mieszaniny. Podano zależności między udziałem objętościowym a masowym. Materiał i metody: Materiał stanowią źródła z literatury z zakresu termodynamiki. W pracy zastosowano metodę analizy teoretycznej. Wyniki: Rezultatem analizy jest opracowanie i podanie wzorów opisujących równanie stanu gazu doskonałego, ciepło właściwe oraz energię wewnętrzną gazów doskonałych i półdoskonałych. W pracy również opracowano wzory dotyczące mieszanin gazów doskonałych i półdoskonałych. Wniosek: Pojęcie gazu doskonałego wprowadzono w celu uproszczenia analizy zachowań gazów i par rzeczywistych.

EN

Introduction and aim: The paper presents the concept of the perfect and semi-perfect gas. Have been given the rights of Boyle-Mariotte, Gay Lussac-Charles and Avogadro. The perfect gas law has been shown in the paper. Has been discussed the specific heat, internal energy and enthalpy for iperfect and semi-perfect gases. The paper presents the concept of a mixture of perfect and semi-perfect gases. The right of Dalton and Leduc have been presented in this paper. In the considerations has been described pound mass, molar and volume participation. Also has been shown a partial pressure, gas constant of the gas mixture, density and molar mass of the mixture. Has been given the relationship between volume and mass participation. Material and methods: Material covers some sources based on the literature in the field of thermodynamics. The method of theoretical analysis has been shown in the paper. Results: The result of the analysis is the elaboration and presenting some formulas which describe the equation of perfect gas, specific heat and internal energy of perfect and semi-perfect gases. In the study also gives some formulas for the perfect and semi-perfect gas mixtures. Conclusion: The concept of a perfect gas was introduced to simplify the analysis of the behavior of real gases and vapors.

5

Finite element analysis of dynamic properties of thermally optimal two-phase composite structure

Nienartowicz M., Stręk T.

Vibrations in Physical Systems

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2014

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Vol. 26

203--210

EN

This paper presents modelling and a FEM analysis of dynamic properties of a thermally optimal two-phase composite structure. Simulations were provided for 2D models. At the first step, topology optimization was performed, where an internal energy was minimized. At the second step, analysis of dynamic properties was executed. Calculations allowed to determine eigenfrequencies and the mode shape of the structure. Solid isotropic material with penalization (SIMP) model was used to find the optimal solution. The optimization algorithm was based on SNOPT method and Finite Element Method.

6

Destruction mechanics: self-destruction

Cherepanov G. P., Esparragoza I. E.

International Journal of Applied Mechanics and Engineering

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2007

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Vol. 12, no 2

565-570

EN

Fracture meehanics studies the cracking of a material while destruction is the fraeturing/separation of a material into smali debris by very many cracks. In the latter case, a fraeture front or wave separates the intact material from that destructed into smali particles. As distinct from fracture mechanies, destruction mechanies does not concern about how and where each crack grows. Its main interest is to study the location and motion of the fracture front. The present paper is a brief presentation of destruction mechanics and, especially, self-destruction, or selfsustaining fracture in former terminology, as its most interesting subject. Destruction in this approach is treated like a specific phase transition of an intact material into a destructed one. The general condition of destruction is formulated in terms of energy. Some problems of destruction mechanies are briefly reviewed, including quasistatie problems of local destruction in stress concentration zones, stability and instability of destruction process, flame drilling, a theory of Tungus meteorite destruction, and dynamic problems such as the problems of underground explosion, collision of brttle bodies, and propagation of a plane fracture wave from a free boundary. The dynamic, explosive growth of the destruction zone occurring by itself, uncontrollably, is called the selfdestruction. Self- destruction starts from a small change in the boundary or loading playing the part of a trigger initiating a fracture wave that propagates at the speed of sound and destructs all material being at the metastable, overstressed condition. The destruction of Batavian tears is a well-known example of self-destruction. Coal bursts and rock bursts as self-destruction phenomena in deep rnines have been known for a long time. Some old but forgotten experiments on explosive self-destruction of glass specimens are described in the paper, as well as some calculations of fraeture waves and an estimate of the size of destructed particles.

7

Podstawowe pojęcia w termodynamice technicznej: energia, praca i ciepło

Kubski P.

Technika Poszukiwań Geologicznych

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2006

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R. 45, nr 1

57-63

PL

Przypomniano podstawowe pojęcia z zakresu termodynamiki technicznej. Zwrócono szczególną uwagę na to, że praca i ciepło są sposobem przekazywania energii, a nie są postaciami czy formami energii, mimo że te trzy ważne pojęcia charakteryzują się tym samym wymiarem i mogą być wyrażane tymi samymi jednostkami. Omówiono również pojęcia energii wewnętrznej oraz entalpii wyrażane także przy pomocy jednostek energii. Kolejnym celem było zwrócenie uwagi, że praca i ciepło różnią się w dodatku przydatnością energetyczną, którą określamy przy pomocy, również tu przypomnianego, pojęcia egzergii.

EN

The basic terms in engineering thermodynamics were reminded. It was taken into special consideration that the work and the heat are the way of energy transfer. These two terms are not energy. Three terms, energy, work and heat, are characterized in the same dimension and can be expressed in the same unit. The definitions of internal energy and enthalpy were also discussed. These another terms can be also expressed in unit of energy. Next aim in work was to take into account, that work and heat differ energetic usefulness, which can be qualified by term of egzergy.

8

Fenomen fluktuacji niskoczęstotliwościowych z widmem 1/f

Stadnyk B, Kołodij Z., Kowalczyk A.

Pomiary Automatyka Kontrola

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2003

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R. 49, nr 7-8

12-14

PL

W artykule przedstawiono problemy analizy fluktuacji niskoczęstotliwościowych w jednorodnych i niejednorodnych metalach i półprzewodnikach. Postawiono tezę o wpływie ruchu Browna cząstek elementarnych na fluktuacje niskoczęstotliwościowe. Zaproponowano model fluktuacyjny wiążący nagromadzoną wewnętrzną energię oraz strukturę sieci krystalicznej z parametrami szumowymi.

EN

In the paper the problem of analysis of low frequency fluctuations in the samples of metals and semiconductors were presented. We came to conclusion that there is the dependence between fluctuations and the Brown`s movement. The proposed fluctuational model connects the spared internal energy and the crystal structure with power of fluctuations.

9

Dynamothermics

Ciężak A.

Metallurgy and Foundry Engineering

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2002

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Vol. 28, no. 1

73-91

EN

It has been demonstrated that the internal energy of an ideal gas may depend exclusively on its pressure, and this energy has been called piezoenergy. Piezoenergy is - an analogue of classical internal energy (depending only on temperature in the case of a perfect gas), if the role of the agent has been taken by the heat gas existing in the entropy space, work - calculated using molar work capacity (analogue of molar heat capacity), has been constituted energy delivered by a corpuscular gas entering or leaving, and heat has been expressed and solely by the product of temperature and shift in the entropy space. Such a description has been created in the field which has been called dynamothermics. From the logical point of view, dynamothermics is equivalent to thermodynamics and uses the same physical quantities as thermodynamics, these quantities, however, play different roles, for instance, the law of the increase of volume corresponds to the law of the increase of entropy. Phenomena in dynamothermics correspond to the specific phenomena in thermodynamics.

PL

Wykazano, że energia wewnętrzna gazu doskonałego może zależeć wyłącznie od ciśnienia i nazwano tę energię piezoenergią. Piezoenergia jest analogiem klasycznej energii wewnętrznej (zależnej tylko od temperatury w przypadku gazu doskonałego), jeśli rolę czynnika przejmie gaz cieplny bytujący w przestrzeni entropowej, pracę - obliczaną za pomocą pracy molowej (analog ciepła molowego), stanowić będzie energia dopływająca lub wypływająca z gazem korpuskularnym, a ciepło wyrazi się - i to wyłącznie, iloczynem temperatury i przesunięcia w przestrzeni entropowej. Opis taki utworzono w dziedzinie, którą nazwano dynamotermika. Od strony logicznej dynamotermika jest równoważna termodynamice i posługuje się tymi samymi wielkościami fizycznymi co termodynamika, ale wielkości te pełnią w niej odmienne role, np. prawu wzrostu objętości odpowiada prawo wzrostu entropii. Zjawiskom w dynamotermice odpowiadają konkretne zjawiska w termodynamice.

10

The substantial balance of internal energy (IE) for extensive quantities as viewed by the balance-theory

Wrzesiński Z.

Engineering Transactions

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2002

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Vol.50, iss.1-2

81-90

EN

The article presents the balance axiom and the basic balance leading to the referential balances of a scalar and vector extensive quantity (EQ). Next the substantial balance of internal energy (IE) has been done, defining the production part which is the sum of IE creation and annihilation, as well as the exchange part which is the sum of IE inflow and outflow through the boundaries of a substantial system. The substantial balance of internal energy (IE) achieved in this way has been reduced to the balance under the conditions of a reversible change, to obtain finally the balance of IE, commonly referred to as the first principle of thermodynamics for extensive quantities (EQs).

11

Substantial balance equation of internal energy as viewed by the balance theory

Wrzesiński Z.

Engineering Transactions

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2002

|

Vol.50, iss.1-2

91-102

EN

The article defines the microscopic substantial system and elementary first-order increments of elementary third-order increments of internal energy (IE), friction heat and heat exchanged between the substantial microsystem and the exterior. A substantial balance of internal energy (IE) has been presented for extensive quantities (EQ) with reference to a substantial microsystem which has been next transformed into a substantial balance equation of the mass density of internal energy (IE). The substantial balance equation of the mass density of internal energy has been integrated for a substantial system throughout the whole substantial area, obtaining a substantial balance equation of internal energy for intensive quantities related to this area. It has also been defined under what conditions this balance equation can be used in the substantial area. In the case of the reversible change, the substantial balance equation of internal energy (IE) for intensive quantities has been reduced to the equation commonly called the first principle of thermodynamics for intensive quantities.

12

Generalised Balance of Internal Energy for an Open System

Wrzesiński Z.

Bulletin of the Polish Academy of Sciences. Technical Sciences

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2001

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vol. 49, nr 4

537-542

EN

The paper presents the definition of mass density of generalised enthalpy and the balance equation of generalised enthalpy for intensive quantities (IQs). The functions of generalised enthalpy have been defined for homogenous fields of intensive quantities and the balance equation of generalised enthalpy - for extensive quantities (EQs). In this respect, the generalised balance of internal energy bas been defined for an open system which, in case of the absence of the exterior impact on the system, bas been reduced to the balance of internal energy for an open system. In the case of a reversible transformation, the generalised balance of internal energy bas been reduced to the balance called the first generalised principle of thermodynamics for an open system and the balance of internal energy has been reduced to the balance called the first principle of thermodynamics for an open system.