Jan Rohde-Brandenburger

57219994094

Publications - 12

Vibroacoustic Investigation of Automotive Turbochargers Focusing on the Effect of Lubricant Temperature and Bearing Conditions

Csaba Tóth-Nagy Márk Pesthy Jan Rohde-Brandenburger Richárd Takács

Publication Name: Lecture Notes in Mechanical Engineering

Publication Date: 2023-01-01

Volume: Unknown

Issue: Unknown

Page Range: 861-870

Description:

The detailed mapping of the rotordynamic properties of a turbocharger is an important tool of turbocharger development, where one of the main focuses is lubricant condition. This is well understandable considering the trend of decreasing viscosity levels of engine lubricants. This article introduces rotordynamic investigations of turbochargers performed on a component testbench. The experiments were carried out with different inlet oil temperatures. The goal was to investigate the effect of oil temperature on rotordynamic properties. The component under investigation was a turbocharger of a 4-cylinder gasoline engine equipped with full-floating hydrodynamic bearings. The application of journal bearings can cause several rotordynamic phenomena at high rotational speeds that are typical of turbochargers. Experiments were conducted on new condition and used conditions (over 50.000 km, in urban traffic) of a turbocharger, where oil temperature varied between 20 ℃ and 120 ℃ in six steps. Lubricant temperature and bearing wear had a noticeable influence on both the synchronous and subsynchronous vibrational behaviour of the turbocharger. The present paper describes the applied testing processes and evaluation methods. Results contributed to ongoing comprehensive research regarding rotordynamic mapping of automotive turbochargers.

Open Access: Yes

DOI: 10.1007/978-3-031-15211-5_71

Comparing the Combustion Process and the Emission Characteristic of a Stationary Heating Device System and an Internal Combustion Engine with Experimental Investigation

I. Zsoldos György Szabados Péter Nagy Jan Rohde-Brandenburger

Publication Name: Periodica Polytechnica Transportation Engineering

Publication Date: 2023-01-01

Volume: 51

Issue: 1

Page Range: 96-104

Description:

Stationary heating devices can be used to warm up the coolant of an internal combustion engine or the cabin air of a vehicle. This kind of heat engine transforms the chemical energy content of liquid fuels into heat energy. The combustion process and the emission of such a device is in focus in this study, which would be the first part in a greater project in the field. Therefore, some relevant parameters have been established. Relevant cycles have been chosen for the kinds of heat engines. It means a normal mode cycle for the stationary device and a WLTC cycle in the case of the direct injection gasoline engine. Fuel used was the same for both. This heat transfer process is such, that the combustion seems to be quite simple and rough in the stationary device compared to that of in internal combustion engine. This means an inhomogenous combustion with non-premixed flame at a low combustion temperature. This situation affects the emission characteristic accordingly, so causes low NOx and relatively high particle relevant emission comes out from the device. As far as the device's particle relevant emission is concerned it would be suitable for further investigation described at the end of the article.

Open Access: Yes

DOI: 10.3311/PPtr.18751

Tribological Properties of the Nanoscale Spherical Y2O3 Particles as Lubricant Additives in Automotive Application

Rajmund Kuti Máté Zs Leskó Árpád Tóth Jan Rohde-Brandenburger I. Szabó

Publication Name: Lubricants

Publication Date: 2022-02-01

Volume: 10

Issue: 2

Page Range: Unknown

Description:

The continuous tribological development of engine lubricants is becoming more and more vital due to its fuel efficiency improvement and lifetime increasing potential. The antiwear additives play a high role in the lubricants to protect the contacting surfaces even in the presence of thinner oil film. Nanoscale spherical particles in the lubricant may increase the necessary protecting effect. This paper presents the results of the experimental tribological investigation of nanoscale spherical Y2O3 (yttria) ceramic particles as an engine lubricant additive. The ball-on-disc tribological measurements have revealed an optimum concentration at 0.5 wt% with about 45% wear scar diameter and 90% wear volume decrease, compared to the reference, neat Group III base oil. The high-magnitude SEM analysis revealed the working mechanisms of yttria: the particles collected in the roughness valleys resulted in a smoother contacting surface, they were tribo-sintered and they have also caused slight plastic deformation of the outer layer of the metallic surface.

Open Access: Yes

DOI: 10.3390/lubricants10020028

Timing Chain Wear Investigation Methods – Review

Csaba Tóth-Nagy Jan Rohde-Brandenburger L. Paulovics

Publication Name: Fme Transactions

Publication Date: 2022-01-01

Volume: 50

Issue: 3

Page Range: 461-472

Description:

Several methods are used for investigating timing chain wear, from fired engine dynamometer tests through tribological model tests to simulations. Research over the past decade has shown that component or tribometer tests can replace expensive engine dynamometer tests in many cases. Simulation methods can further reduce the cost and time of development. Simulation models require experimentally defined input parameters; therefore, experiment-based methods cannot be completely avoided. However, a comprehensive comparison or validation of the various experimental and simulation techniques is difficult, as the literature on the topic is relatively scarce. This study aims to give a systematic comparison of the results of several investigation methods of timing chain wear, supported by data measured at Széchenyi István University, such as fired engine dynamometer tests, cold dynamometer tests, component tests, and tribometer tests, presenting their benefits and limitations, where possible through examples and results. The study also provides an insight into the compatibility of different measurement methods.

Open Access: Yes

DOI: 10.5937/fme2203461P

A Review on Friction Reduction by Laser Textured Surfaces in Internal Combustion Engines

András Lajos Nagy Jan Rohde-Brandenburger Gabor Laki Barna Hanula

Publication Name: Tribology Online

Publication Date: 2022-01-01

Volume: 17

Issue: 4

Page Range: 318-334

Description:

The internal combustion engine will be required as a bridge-technology in the upcoming decades to achieve a significant reduction in local emissions in the mobility, and logistics sector. Alternative fuel technologies will present new mechanical engineering challenges, including increasing efficiency and reducing mechanical losses. Textured surfaces with appropriate manufacturing parameters can enhance lubrication, and reduce friction in sliding and rolling contacts, e.g., journal bearings, or the piston ring – cylinder subsystem. This paper gives an overview of 80 scientific works related to laser surface technologies, with an emphasis on surface texturing for friction reduction from the viewpoint of engine development. The most common texture types, further directions, and general challenges are highlighted in the summary.

Open Access: Yes

DOI: 10.2474/trol.17.318

Rapid fleet condition analysis through correlating basic vehicle tracking data with engine oil ft-ir spectra

Charlotte Besser Péter Raffai András Lajos Nagy Bettina Ronai Adam Agocs Jan Rohde-Brandenburger Nicole Dörr

Publication Name: Lubricants

Publication Date: 2021-12-01

Volume: 9

Issue: 12

Page Range: Unknown

Description:

Engine oil condition and tribological performance are strongly interrelated. Accordingly, oil condition monitoring is common in various applications. This is especially important, as oil condition depends on the fueling and utilization profile of an internal combustion engine. Common practice involves the measurement of various parameters, such as the total acid number and total base number, oxidation, nitration, viscosity, and elemental composition; thus, it can be time-consuming and resource-intensive. This study provides a methodology for rapid analysis for large vehicle fleets or sample sizes, using only Fourier-transformed infrared spectroscopy and the subsequent multivariate data analysis offers a rapid alternative to commonly available methods. The described method provides a rapid, cost-efficient, and intuitive approach to uncovering differences in the oil condition. Furthermore, understanding the underlying reasons in engine construction and the resulting chemical degradation is also possible.

Open Access: Yes

DOI: 10.3390/lubricants9120114

Development of comparative investigation method for timing chain wear analysis using oscillating tribometer

Csaba Tóth-Nagy Rajmund Kuti Jan Rohde-Brandenburger L. Paulovics

Publication Name: Acta Technica Jaurinensis

Publication Date: 2021-11-24

Volume: 14

Issue: 4

Page Range: 406-423

Description:

This paper presents the development of a test procedure to investigate timing chain components under abrasive stress on a tribometer. Engine developers use cost and time expensive engine dynamometer tests to investigate timing chain life expectancy under different conditions. Tribometer tests are fast and cost effective, but these use standardized specimen material and geometry that greatly differ from the original tribological system of the timing chain. Manufacturing specimens from the original chain material using the original technology is complicated; surface quality and hardness properties cannot be guaranteed. The aim of research was to develop a test method for rapid and cost-effective comparison of engine lubricants, timing chain materials or coatings, as well as to assess the wear resistance of the chain to contaminants. Various uncontaminated and carbon black blended lubricants were compared using standard-based ball-on-disc tribometer tests to tribometer tests using actual timing chain components (bush-on-pin test) of a Diesel engine. Lubricants were ranked in terms of coefficient of friction and wear. Results showed that bush-on-pin tests were comparably suitable for testing lubricants when evaluated against standard ball-on-disc tribometer tests.

Open Access: Yes

DOI: 10.14513/actatechjaur.00620

Comprehensive assessment of oil degradation patterns in petrol and diesel engines observed in a field test with passenger cars – Conventional oil analysis and fuel dilution

Charlotte Besser András Lajos Nagy Adam Agocs Jan Rohde-Brandenburger József Perger Michael Schandl Zsolt Tabakov Nicole Dörr

Publication Name: Tribology International

Publication Date: 2021-09-01

Volume: 161

Issue: Unknown

Page Range: Unknown

Description:

Requirements for modern internal combustion engines are lower emissions, higher power density and longer maintenance intervals. These trends increase the demands on engine components, including lubricants. In a field study of petrol and diesel vehicles, oil condition of 47 engine oils from 12 vehicles are correlated with fresh oil properties and operating conditions, i.e., trip length and speed. Long-range petrol vehicles displayed accelerated chemical oil degradation compared to diesel vehicles. An explanation for this behaviour is assumed to be the difference air-to-fuel ratio. Short-range petrol vehicles showed an even faster oil degradation and significant changes in oil viscosity due to fuel dilution. Diesel vehicles exhibited higher soot loading and more pronounced engine wear indicated by iron content in the oils.

Open Access: Yes

DOI: 10.1016/j.triboint.2021.107079

Artificial aging experiments of neat and contaminated engine oil samples

I. Zsoldos András Lajos Nagy Jan Rohde-Brandenburger

Publication Name: Lubricants

Publication Date: 2021-06-01

Volume: 9

Issue: 6

Page Range: Unknown

Description:

This study highlights how the results from an artificial engine oil aging method compare to used engine oil samples collected from a vehicle fleet. Additionally, this paper presents the effect of contaminating the oil during aging with synthetic fuel alternatives on the physical and chemical properties of artificially aged engine oil samples. A laboratory-scale artificial thermo-oxidative aging experiment was conducted on multiple samples of commercially available formulated fully-synthetic SAE 0W-30 engine oil. The goal of the experiment was to establish the validity of the artificially aged samples as well as the validity of the underlying process in reproducibly fabricating small batches of aged engine oil with comparable chemical and physical properties to real-life used oils. Eight samples were subjected to distinct load cases (temperature, air flow rate, sample volume and aging time). Six additional samples were subjected to an intermediate load case, with five of them contaminated with selected conventional fuels and novel automotive fuel candidates. Conventional oil analysis was conducted on each sample to determine oxidation, residual additive content, kinematic viscosity and total base number. Additionally, analysis results were compared to in-use engine oil samples through PCA. The resulting oil condition after aging is in accordance with independently published results in terms of zinc dialkyldithiophosphate content and kinematic viscosity. Contaminated aging with OME3-5 resulted in a drop in antioxidant content and elevated kinematic viscosity. Based on the comparison with in-use samples, artificial aging of 200 mL engine oil at 180◦ C with 1 L/min air flow for 96 h can produce similar oil conditions as mixed vehicle use for 7000 km.

Open Access: Yes

DOI: 10.3390/lubricants9060063

Experimental Investigation of Vibroacoustic Behaviour of an Automotive Turbocharger with Semi-floating Bearing

Balázs Rácz Péter Sass Márk Pesthy Jan Rohde-Brandenburger

Publication Name: Lecture Notes in Mechanical Engineering

Publication Date: 2021-01-01

Volume: 22

Issue: Unknown

Page Range: 245-255

Description:

Due to the strict European emission standards and the constant aspiration for the higher power density, turbochargers became essential components of the modern internal combustion engines. Turbochargers are high-speed operating machines thus the design of the rotor and the bearing system requires special attention. The motions of the rotor are affected by several parameters, such as bearing design, clearances, structure of the surface and also the quality and the physical properties of the used lubricant. If the motions of the rotor are intensive in a wide rotational speed range, the bearing load increases, resulting in a reduced lifespan. The motion of the rotor induces vibrations, which leads to audible noise emission to the environment. In this article, the vibrations of a four-cylinder spark ignition engine’s turbocharger are presented, based on component test-bench experiments. Furthermore, the main vibration components and their influencing factors are briefly introduced. During the experiments, the noise and vibrations of the turbocharger have been measured with different viscosity grade oils from 20 °C to 140 °C inlet temperature. The results showed that the amplitudes of both the synchronous and subsynchronous vibrations changed significantly and the volumetric flow is highly dependent on the temperature. The effect of the changing oil temperature will be analyzed with an emphasis on the subsynchronous vibrations and the possible cause of the phenomenon will be presented. Finding the optimal parameters with the lowest possible vibration response could result in an extended lifetime and provides important information for the balancing process during production.

Open Access: Yes

DOI: 10.1007/978-981-15-9529-5_21

Tribological Investigation of Applicability of Nano-Sized Cupricoxide (CuO) Ceramic Material in Automotive Vehicles

Rajmund Kuti Árpád Tóth Jan Rohde-Brandenburger I. Szabó

Publication Name: Fme Transactions

Publication Date: 2021-01-01

Volume: 49

Issue: 2

Page Range: 335-343

Description:

Due to the continuously increasing requirements of the internal combustion engines, the lubricants and their additives have to be further developed. One possible solution is the application of ceramic nanoparticles as friction modifier and wear decreaser additives. This paper presents the tribological investigation of cupricoxide (CuO) nanoparticle mixed in neat Group 3 base oil. To analyse its properties, simplified ball-on-disc friction experiments were carried out in the tribological laboratory in the Széchenyi István University in Győr, Hungary. The arisen wear scars were analysed with different, highresolution microscopes to understand the working mechanism of the nanoparticles. The results have indicated an optimum concentration of nanoparticles at 0.5wt% where both the average friction coefficient and the wear scar diameter were reduced by 15%. The microscopical investigation revealed the reduction of copper material from the CuO material, and it has mended to the rubbing surface forming a protective film on the metal surface.

Open Access: Yes

DOI: 10.5937/fme2102335T

Design and Testing of a Water Injection System of a Turbocharged Spark Ignition Engine in Testbench Environment

Máté Tóth Balázs Rácz Attila Gyuris Péter Sass Jan Rohde-Brandenburger

Publication Name: Lecture Notes in Mechanical Engineering

Publication Date: 2021-01-01

Volume: 22

Issue: Unknown

Page Range: 321-333

Description:

In the scope of this article, the design and testing of a water injection system applicable for a spark ignition engine are presented. Increasingly stringent emission standards within the framework of EURO7 require either directly or indirectly the internal combustion engines to be optimized across the entire field of an engine map, therefore they must comply with the emission standards at each operating point. The greatest challenge is expected to be the Lambda = 1 operation on the full field. The conversion efficiency of the exhaust gas after treatment systems is the highest at this point, therefore it is foreseeable that no deviation can be made. As a result, fuel enrichment for performance enhancement and to protect components against thermal load will not be tolerated, so the resulting thermal loads will need to be reduced in other ways. It is possible to reduce the excess thermal loads by using water injection. Evaporation of water in the intake system and combustion chamber takes off heat and the temperature of the contacting components and fluids decreases. The affected components include pistons, combustion chamber, cylinder head, exhaust valves, exhaust manifold, turbine wheel, turbine housing, and as a medium, the temperature of the intake air. Reducing the temperature of some components is important in the aspect of mechanical strength, while for some components the knock limit can be extended. This article presents the detailed design process and testing phase of a water injection system. An important aspect in system design is compatibility with different engine layouts in a cost-effective manner. Injector nozzle testing also includes analysis of mass flow, dispersion and spray pattern. The scope of the work is the implementation of a water injection system, which is capable of performing measurements in testbench environment at the Department of Internal Combustion Engines and Propulsion Technology of Széchenyi István University. The result of the measurements is the successful cylinder selective application of water injection to the intake system, whereby the addition of water reduces the temperature of the intake air and the exhaust gas, which can be reduced to standard calibration temperature in Lambda 1, without fuel enrichment.

Open Access: Yes

DOI: 10.1007/978-981-15-9529-5_29