Wyniki wyszukiwania - BazTech

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Reduction of dynamic loads in the drive system of mining scraper conveyors through the use of an innovative highly flexible metal coupling

Wieczorek Andrzej Norbert, Konieczny Łukasz, Wojnar Grzegorz, Wyroba Rafał, Filipowicz Krzysztof, Kuczaj Mariusz

Eksploatacja i Niezawodność

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2024

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Vol. 26, no. 2

art. no. 181171

EN

The article provides a discussion on the results of the authors’ original studies of a power transmission system of a mining scraper conveyor coupled with an innovative highly flexible clutch, conducted in operating conditions. The research consisted in establishing the static characteristics of the highly flexible clutch in question, determining the torsional vibrations of the said highly flexible clutch and the vibrations of the transmission housings at a test rig, verifying if the coupling between the innovative flexible clutch and a typical scraper conveyor drive unit was correct, and testing durability of individual components of the highly flexible clutch. Following the aforementioned tests and based on the static characteristics of the highly flexibleclutch examined, one can distinguish three phases of its operation: initial, main, and final –all differing in terms of flexibility. Furthermore, upon increasing the flexibility of the metal clutch, a significant decline in the root mean square (RMS) values of linear vibration accelerations was observed compared to the blocked condition of the clutch. It was further noticed that, as the torsional vibrations of the clutch shaft were increasing, the linear vibrations measured at the transmission bearing housings were decreasing significantly. Based on the tests conducted in operating conditions, it was found that the durability of the flexibilising system (bolt and nut) was sufficient and that there were no thermal effects associated with the motion of the system components.

2

Analysis of security vulnerabilities in vehicle on-board diagnostic systems

Pełechaty Piotr, Konieczny Łukasz

Diagnostyka

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2024

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Vol. 25, No. 3

art. no. 2024310

EN

The article explains the different types of on-board diagnostic systems (OBD) used in motor vehicles, as well as the impact of the latest automotive security norms on diagnostic interface security. The paper focuses on identifying potential security threats in on-board diagnostic systems used in automotive control units. During the research, a diagnostic interface device of its own design, carrying out special test procedures, was excavated. The research was conducted on several vehicles and ECUs, applying black box penetration testing. The paper's goal is to list all identified vulnerabilities in diagnostic protocol implementation and suggest some corrective actions for software that would increase security. The authors defined a list of low-cost software requirements that can be easily implemented on most modern ECUs.

3

Study of radial slide bearings with a floating ring considering the physical properties of oil

Mazurkow Aleksander, Homik Wojciech, Konieczny Łukasz

Transport Problems

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2022

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T. 17, z. 4

27--40

EN

Radial slide bearings are typically used in turbochargers (among other applications), owing to their simple design and advantages, such as good heat dissipation from the working zone, high stability of operation and low resistance to motion. The current research is both experimental and theoretical. In a state of static equilibrium, the operation of a bearing can be described using a system of five coupled differential equations. The bearing’s operating parameters are related to the type of oil used. Two types of oil, VG46 and VG68, were used for testing. In accordance with the applicable standard, the tolerance of kinematic viscosity of oils is ±10%. The results imply a significant influence of the oil class and viscosity tolerance on the resistance to motion caused by internal friction forces in the oil. In conclusion, it seems advisable that the calculation procedures currently in use should include the slide bearing design optimisation by taking the resistance to motion in the bearing into account.

4

Analysis of the share of natural gas in the total fuel supply dose on the combustion process in a CRDI engine

Wierzbicki Sławomir, Boruta Grzegorz, Konieczny Łukasz, Łazarz Bogusław

Transport Problems

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2022

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T. 17, z. 1

141--150

EN

Natural gas is one of the potential combustion engine fuels whose proportion in the overall energy balance is expected to increase. Owing to some of its properties, its use requires a dual-fuel supply system; thus, the use of natural gas as a fuel for diesel engines is currently limited. Systems that supply gas fuel to diesel engines do not usually interfere with the engine control system. This solution significantly reduces system-installation costs. However, as demonstrated in the present study, it considerably changes the course of the combustion process, which increases thermal and mechanical loads. In this case, the combustion process can be controlled by changing the liquid fuel injection pressure or advancing the injection angle. This, however, requires interference with the engine control system.

5

Analysis of the possibility of using the phase angle in the EUSAMA method as an additional diagnostic parameter in the assessment of the technical condition of the vehicle suspension system

Konieczny Łukasz, Filipczyk Jan

Diagnostyka

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2022

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Vol. 23, No. 4

art. no. 2022414

EN

Vehicle suspension system diagnostics is essential to both operation and maintenance of automotive vehicles. Diagnostic methods should provide signals that in-service defects have occurred as early as possible and make it possible to identify such defects in an unambiguous manner. Among the most popular oscillatory methods used to examine the technical condition of suspension systems, the EUSAMA method, developed by the European Shock Absorbers Manufacturers Association, has enjoyed particularly wide application, and it consists in establishing the ratio between the minimum value of the wheel adhesion force within the band of resonance of unsprung masses and the static wheel load value, expressed in per cent. Technical condition classification is based on comparing the values of what is commonly referred to as the EUSAMA coefficient (percentage ratio of a minimum wheel load force to a tangential vehicle wheel load on a test stand plate) for two wheels of a single axle. Such a test stand typically features only a load force sensor integrated with the test plate. The modification proposed by the authors involves installing an additional test plate displacement sensor at the test stand. When performed simultaneously, measurements of the load force affecting the plate and of its displacement make it possible to determine the phase angle between the relevant signals and to analyse the possibility of using the phase angle as an additional source of information about the technical condition of the vehicle suspension system.

6

Emissions from a medium-duty CRDI engine fuelled with diesel-biodiesel blends

Duda Kamil, Wierzbicki Sławomir, Mikulski Maciej, Konieczny Łukasz, Łazarz Bogusław, Letuń-Łątka Magdalena

Transport Problems

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2021

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T. 16, z. 1

39--49

EN

In the present work, biofuels produced from different raw fatty materials have been proposed as a dominant fuel component in biodiesel-diesel fuel blends. Biofuels were produced from pork lard and rapeseed oil by alkali transesterification using methyl alcohol. Blends of biofuels in volumetric proportions of 60 and 80% of the biocomponent and the remaining part of the conventional fuel were used in a compression ignition engine designed for medium-duty vehicles. The experiments were conducted at two engine rotational speeds (1500 and 3000 rpm, respectively) and a set of load conditions (50, 100, and 200 Nm, respectively). The tests focused on engine efficiency parameters (brake-specific fuel consumption and brake fuel conversion efficiency) as well as exhaust gas emissions (hydrocarbons, carbon monoxide, and carbon dioxide were determined). The obtained results indicate that blends containing biocomponents produced from pork lard were characterized by superior fuel consumption and efficiency results, compared to blends containing biocomponents produced from rapeseed oil. In terms of exhaust emissions, biocomponents produced from pork lard were also characterized by lower emission of all of the examined components compared to rapeseed methyl ester-diesel blends. This study proposes that fuel components obtained from custom (animal) raw-fatty material can be an effective substitute for commonly used rapeseed oil methyl esters.

7

Effect of fail-safe mode on the damping characteristics of a bypass-controlled shock absorber

Konieczny Łukasz

Transport Problems

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2020

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T. 15, z. 3

43--52

EN

The article provides and discusses results of tests of a bypass-controlled hydraulic shock absorber studied at a test stand (mechanical inductor), making it possible to plot work charts and determine velocity characteristics. Measurements of the shock absorber performance were conducted at different values of velocity and forced travel. The measurements were carried out for two statuses, i.e. for the emergency power failure condition and for normal setting. The results thus obtained can be used in simulation tests as input shock absorption characteristics for different technical conditions.