Wyniki wyszukiwania - BazTech

1

Study on the friction coefficient between eggshells and powders with various chosen surfaces

Wozniak Marek, Kuchar Maciej, Zakrzewski Sergiusz, Siczek Krzysztof, Obraniak Andrzej, Rylski Adam, Kubiak Przemyslaw

Technologia i Jakość Wyrobów

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2023

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R. 68

111--151

EN

Transport of fresh or powdered chicken eggs uses conveyors with elements made of steel or plastics, and surfaces often coated by Teflon. Various forms of eggs contact with said surfaces and are subject to friction processes between them. The frictional resistances cause a load on the devices driving the conveyors and a local and temporary increase in temperature in the contact zones and allow the abrasive wear of both the surfaces of the conveyors, packages and the eggshells themselves. This study aimed to determine such the coefficient of friction and wear intensity at various contacts. The friction and wear tests were conducted on two tribotesters and the results are shown in the article.

PL

Transport świeżych lub sproszkowanych jaj kurzych wykorzystuje przenośniki z elementami wykonanymi ze stali lub tworzyw sztucznych, a powierzchnie często pokryte teflonem. Różne formy jaj stykają się ze wspomnianymi powierzchniami i podlegają procesom tarcia między nimi. Opory tarcia powodują obciążenie urządzeń napędzających przenośniki oraz lokalny i tymczasowy wzrost temperatury w strefach styku i pozwala na zużycie ścierne powierzchni przenośników, pakietów i samych skorupek jaj. Badanie to miało na celu określenie takiego współczynnika tarcia i intensywności zużycia w różnych stykach. Testy tarcia i zużycia przeprowadzono na dwóch tribotesterach, a wyniki pokazano w artykule.

2

Research of damage to the rear wheel rim in a tipper-truck

Kubiak Przemyslaw, Wozniak Marek, Zakrzewski Sergiusz, Siczek Krzysztof, Rylski Adam, Mrowicki Adam, Matej Jan, Deda Jakub, Knap Lech

Bulletin of the Polish Academy of Sciences. Technical Sciences

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2022

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Vol. 70, nr 3

art. no. e141000

EN

Serious damage to the inner rim of the rear twin wheel in one dump truck was noted during the operation of the fleet performing transport tasks. It was a drive wheel, and its damage occurred while driving with a load exceeding the permissible value. The examination of selected fragments of the damaged rim surface was conducted visually as well as using a digital microscope with a portable head. The measurements of the Vickers hardness and microscopic observations of the material structure of the sample cut along the thickness of the rim disk were carried out. The drive torque loading of the twin wheels of the tipper-truck rear axle, under their mating with different kinds of road roughness and under various vertical loads of the wheels was calculated. An analysis of stress distributions in the rim modelled using the Finite Element Method was also conducted for several possible scenarios of wheel loading. The damage to the rim was caused by simultaneous action of several factors, such as overloading the car, poor condition of the tires, loading the drive wheel by a part of the vehicle weight and the driving torque, and hitting a wheel on a cavity in a dirt road, causing a temporary relief of one of the tires on a twin wheel.

3

Nonlinear method of precrash vehicle velocity determination based on tensor product of Legendre polynomials - luxury class

Gosławski Łukasz, Sys Ewa, Mrowicki Adam, Krukowski Mateusz, Ma Yanlin, Kubiak Przemyslaw

Archiwum Motoryzacji

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2022

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Vol. 95, nr 1

53--64

EN

Presented paper discusses a new, nonlinear approach to EES (Equivalent Energy Speed) parameter determination in frontal car collisions. This method is based on tensor product of Legendre polynomials and in this case considers Luxury car class. Methods that are used up till now are based on a linear dependency between mass, velocity and deformation. This is of course a simplification that was necessary, due to limitation in computation power of computers when this method was introduced decades ago. The contemporary resources allowed Authors to develop a much more sophisticated method. The mathematical model was developed using data shared by National Highway Traffic Safety Administration (NHTSA). This database covers a large number of test cases along with various information including vehicle mass, crash velocity, chassis deformation etc. New method proves to be more accurate than the currently used approach utilizing linear dependency of deformation force and deformation of the vehicle.

4

The effect of SiO2 nanoparticles content in engine oil on tribological properties of valvetrain chain transmission components

Spinache Edward, Trandafir Adrian, Diaconu Mihai, Ozuna Gustavo, Wozniak Marek, Kubiak Przemyslaw, Siczek Krzysztof

Combustion Engines

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2019

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R. 58, nr 4

4--12

EN

The drive from the crankshaft to the camshaft in an internal combustion engine is usually carried out by means of a cogged belt transmission or a chain transmission when high millage is required without service operations. The valvetrains in CI engines sometimes use the gear transmissions, and the historical rather bevel gear can be found in old cars of collectors or in some motorcycle engines. The chain gear used in SI engines has a two- or three-row chain with high strength, due the unevenness of loads that additionally induce chain pulling and valve timing deregulation. The chain transmission requires the use of pre-tensioners, usually self-acting and driven by springs or oil pressure. The vibrations and chain runout are limited using plastic guides placed on the outside of the long straight sections of the chain. The model of the chain transmission developed with the use of the Finite Elements Method, which operates under oil lubrication conditions, was analyzed. Such the model allowed obtaining weight and mass inertial moments of components. The aim of the study was to evaluate the effect of SiO2 nanoparticles content in engine oil on the friction between chain transmission components. The resulted values of the friction torque in the chain transmission operating in different conditions of lubrication have been presented in the paper.

5

Nonlinear method of vehicle velocity determination based on inverse system and tensor product of Legendre polynomials - intermediate class

Goslawski Lukasz, Gralewski Jacek, Krukowski Mateusz, Kubiak Przemyslaw, Manko Maria, Mrowicki Adam, De Sousa Ricardo Alves, Sys Ewa

Archiwum Motoryzacji

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2019

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Vol. 83, nr 1

133--149

EN

Presented paper discusses two different nonlinear approaches to precrash velocity determination for vehicles from Intermediate Car Class. Data that was used to perform analyses introduced in this paper was taken from National Highway Traffic Safety Administration (NHTSA) database. Such database is comprised of substantial number of crash cases and main focus was put on frontal impacts. Hitherto used energy methods are based on linear model which proves to be inaccurate and producing significant errors. Presented considerations concern the inverse system and tensor product of Legendre polynomials. The focus of those methods is to establish the value of nonlinear coefficient bk which is the slope factor of precrash velocity Vt and deformation ratio Cs function.

6

Nonlinear method of determining the vehicle pre-crash speed based on B-spline with propabilistic weights - subcompact car class

Kubiak Przemyslaw, Sys Ewa, Goslawski Lukasz, Manko Maria, Gralewski Jacek, Krukowski Mateusz, De Sousa Ricardo Alves, Mrowicki Adam, Soghabatyan Tigran, Zou Tiefang

Archiwum Motoryzacji

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2019

|

Vol. 85, nr 3

5--18

EN

A new non-linear method utilizing the work W of car deformation is considered in this study. The car deformation is defined as an algebraic function of deformation ratio Cs. The method of variable correlation is exploited in order to develop experimental data. To determinate mathematical model parameters, data from the NHTSA database including frontal crash tests are used. Such database is comprised of substantial number of crash cases and main focus was put on frontal impacts. In the non-linear method used so far, the so-called energetic approach, collisions are considered non-elastic. The speed threshold defining the elastic collision was set to be 11 km/h. This simplistic approach is used to determine the linear relation of energy loss during deformation on deformation coefficient Cs. Deformation points C1-C6 are taken into account while calculating a mean value that defines this coefficient. A more accurate non-linear method as well as more complex form of deformation coefficient is suggested to determine the work of deformation in this paper. The focus of those methods is to establish the value of nonlinear coefficient b_k which is the slope factor of precrash velocity Vt and deformation ratio Cs function.

7

Analysis of braking marks left by vehicles equipped with ABS with IR spectroscopy

Gosławski Lukasz, Kubiak Przemyslaw, Mrowicki Adam, Soghabatyan Tigran, Sys Ewa, Wang Ying-Wei, Zou Tiefang

Archiwum Motoryzacji

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2019

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Vol. 84, nr 2

33--43

EN

This paper presents the possible use for IR spectroscopy to reveal skid marks left by cars equipped with Anti-lock Braking System. Detailed analysis of literature showed that there is no method that can be used in order to investigate this kind of tire marks. Up till now only two techniques have been devised. The first one is Method of Image Refinement which consists of transforming the image from the scene of the accident using dedicated graphics software. Second method includes analysis of traces using a thermal imaging camera. This study presents an innovative approach to the problem. Numerous analyses using IR spectroscopy were conducted to check the suitability of this method. The research performed on a Thermo Scientific FTIR Nicolet iS50 Spectrophotometer with an ATR attachment. 40 samples from 10 different types of asphalt were prepared. Each sample was measured 3 times to create its spectrum. The results were analyzed thoroughly using the dedicated SpectraGryph software. Analysis show that the wavelength which makes the braking marks visible is found within the mid-infrared range. Finally, it was found wavelength in which skid marks should be visible. This range is located in the mid-infrared.