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1

Reducing wheel wear of a motorised metro car on a curved track with a small curve radius

Matej Jan, Orliński Piotr

Pojazdy Szynowe

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2023

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Nr 3-4

25--32

EN

A structural solution was proposed to enable passive control of the wheelsets of a motorised metro car on curved track with a small curve radius. This effect was achieved by varying the stiffness of the guidance of the wheelsets in the horizontal plane of the frame of each bogie on which the wagon body rests. This ensured the required critical speed of the metro wagon when moving on straight track, and allowed for reduced mechanical wheel wear and better steering of the bogies when moving on curved track with a small radius of curvature. Parameters specific to the design of modern metro cars were taken into account. Current knowledge of non-linear lateral dynamics of rail vehicles and the specialist computer programme Vi-Rail were used to perform the calculations involving simulation models.

2

New possibilities to reduce wheel and rail wear in the operation of metro wagons on curved track with small curve radii without considering propulsion and braking systems

Matej Jan, Orliński Piotr

Eksploatacja i Niezawodność

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2023

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Vol. 25, no. 1

art. no. 15

EN

This paper analyses the parameters relevant to the operation of underground cars in traffic on straight and curved tracks with small curve radii. Current knowledge of non-linear lateral dynamics of rail vehicles and the specialist computer programme Vi-Rail were used to build models and perform simulation calculations. A solution was proposed to enable passive control of wheelsets with very high guiding stiffnesses, without the need for systems to force the axles of the wheelsets to align radially in a curved track. This effect was achieved by varying the guidance stiffness in the horizontal plane of the frame of each bogie. The adopted course of action offers simplicity of solution, low manufacturing costs, high critical speed on straight track and extended service life of the metro wagons resulting from reduced mechanical wear of wheels and rails. A multi-criteria evaluation was carried out, confirming improved bogie controllability and reduced impact of the metro wagon wheelsets on the curved track. Comparisons were made of the design volumes for metro model wagons with bogies with symmetric and unsymmetric axle-guide stiffness arrangements of the wheelsets.

3

Impact of an Electric Locomotive on a Perfectly Smooth Railway Track in Terms of Rail Corrugation Formation

Matej Jan, Orliński Piotr

Advances in Science and Technology. Research Journal

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2023

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Vol. 17, no 5

77--88

EN

Purpose of the article is to demonstrate that a high-speed electric locomotive, driven by asynchronous motors in a hollow shaft arrangement and swing-out couplings, can generate corrugation conditions on the surface of new and smooth rails on straight and curved track. Most studies carried out in this area is usually concerned with the response of the power train to kinematic excitation from a track where corrugations are already present. The novelty of the look presented in the article is to establish the influence of the vehicle's driveline and the parameters of a perfectly smooth formation track on the mechanism of corrugation. A four-axle EU11 electric locomotive, produced in Poland in the late 1990s, has been selected for analysis. A complete electro-mechanical model of the locomotive was built using the Vi-Rail software and prepared for simulation on straight and curved track. A non-linear model of wheel-rail contact was included and the contact forces were determined for the locomotive model in motion with the active power system. Unbalanced inertia forces generated by the scattering of stiffness characteristics of the coupling links, have been included to the propulsion system as an additional source of dynamic excitations. The complexity of the obtained results was influenced by the fact that simulation studies were carried out in both the time and frequency domains. The results obtained in the time domain were used to calculate the vertical and torsional vibration frequencies with respect to the driving wheelsets. One of the most important results of the simulation studies carried out is the determination of the effect of locomotive acceleration on the frequency of resonant torsional vibrations of the wheelsets in straight and curved track traffic.

4

Hydro-treated vegetable oil as a potential biofuel for self-ignition engines

Sikora Mieczysław, Orliński Piotr, Matej Jan

Transport Samochodowy

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2022

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z. 1

14--19

EN

Hydro-treating vegetable oils or animal fats is an alternative process to esterification for the production of biodiesel. Hydro-treated products are also called renewable diesel fuels. Hydro-treated vegetable oils (HVO) do not have the harmful effects of FAME biodiesel such as increased NOₓ emissions, deposit formation, storage stability problems, faster aging of the engine oil or poor cold performance. HVO are straight chain paraffinic hydrocarbons which are free of aromatic hydrocarbons, oxygen and sulphur and have a high cetane number. In the article below, the authors conduct a comprehensive analysis and evaluation of the possibility of running compression-ignition engine on the hydro-treated vegetable oil, which is a second-generation biofuel. On its basis, the information on the assessment of emissions of selected toxic components of exhaust gases and pollutants of the injection system when the engine is powered with this type of fuel, was systematized. The article ends with conclusions from the conducted analyses.

PL

Motor Transport ISSN 1731-2795 Volume (65), Issue (1), 2022 DOI: 10.5604/01.3001.0015.8709 Hydrorafinowany olej roślinny jako potencjalne biopaliwo do zasilania silników o zapłonie samoczynnym Mieczysław Sikora mieczyslaw.sikora@pw.edu.pl Instytut Pojazdów i Maszyn Roboczych PW, Zakład Silników Spalinowych Piotr Orliński piotr.orlinski@pw.edu.pl Instytut Pojazdów i Maszyn Roboczych PW, Zakład Silników Spalinowych Jan Matej jan.matej@pw.edu.pl Instytut Pojazdów i Maszyn Roboczych PW, Zakład Pojazdów Szynowych Streszczenie: Hydrorafinacja olejów roślinnych lub tłuszczów zwierzęcych jest procesem alternatywnym do estryfikacji służącej do produkcji biodiesla. Produkty hydrorafinowane nazywane są również odnawialnymi olejami napędowymi. Hydrorafinowane oleje roślinne (HVO) nie mają szkodliwych skutków biodiesla typu FAME, takich jak zwiększona emisja NOₓ, tworzenie się osadów, problemy ze stabilnością przechowywania, szybsze starzenie się oleju silnikowego lub złe właściwości w niskich temperaturach. HVO to prostołańcuchowe węglowodory parafinowe, które są wolne od węglowodorów aromatycznych, tlenu i siarki oraz mają wysoką liczbę cetanową. W poniższym artykule autorzy dokonują kompleksowej analizy i oceny możliwości zasilania silnika o zapłonie samoczynnym hydrorafinowanym olejem roślinnym będącym biopaliwem drugiej generacji. Na jej podstawie usystematyzowano informacje dotyczące oceny emisji wybranych składników toksycznych spalin oraz zanieczyszczeń układu wtryskowego przy zasilaniu silnika tego typu paliwem. Artykuł kończą wnioski z przeprowadzonych analiz.

5

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.