TY - JOUR AU - Kulcsár, Klaudia AU - Zsoldos, Ibolya TI - Mechanical Studies of Subperiosteal Implants JF - PERIODICA POLYTECHNICA-MECHANICAL ENGINEERING J2 - PERIOD POLYTECH MECH ENG VL - 2024 PY - 2024 SN - 0324-6051 DO - 10.3311/PPme.23706 UR - https://m2.mtmt.hu/api/publication/34535659 ID - 34535659 AB - When designing subperiosteal implants, mechanical testing of the implant and abutment is inevitable. Subperiosteal implants and their abutments are medical devices made to order, so each implant requires a separate design, since each patient has a different bone surface, for which the implant must be designed. For the mechanical testing of subperiosteal implants, a new test apparatus was constructed, on which mechanical simulations were carried out, the subperiosteal implants were tested together with their abutments. In addition to the finite element analysis simulation, the test apparatus can also be used to determine how much force is generated by the chewing force on the subperiosteal implant and its abutment as a result of the chewing mechanism. LA - English DB - MTMT ER - TY - JOUR AU - Horváth, Szabolcs AU - Kovács, József Gábor TI - Effect of Processing Parameters and Wall Thickness on the Strength of Injection Molded Products JF - PERIODICA POLYTECHNICA-MECHANICAL ENGINEERING J2 - PERIOD POLYTECH MECH ENG VL - 68 PY - 2024 IS - 1 SP - 78 EP - 84 PG - 7 SN - 0324-6051 DO - 10.3311/PPme.24068 UR - https://m2.mtmt.hu/api/publication/34692739 ID - 34692739 N1 - Funding Agency and Grant Number: National Research, Development and Innovation Office, Hungary [2020-1.2.3-EUREKA-2021-00010, 2019-1.1.1-PIACI-KFI-2019-00205, 2018-1.3.1-VKE-2018-00001]; Horizon Europe Framework Programme [RRF-2.3.1-21-2022-00009]; Recovery and Resilience Facility of the European Union; Ministry of Culture and Innovation of Hungary from the National Research, Development and Innovation Fund; [101079051 - IPPT_TWINN]; [TKP-6-6/PALY-2021] Funding text: This work was supported by the National Research, Development and Innovation Office, Hungary (2020-1.2.3-EUREKA-2021-00010, 2019-1.1.1-PIACI-KFI-2019-00205, 2018-1.3.1-VKE-2018-00001) . This research was funded by the Horizon Europe Framework Programme and the call HORIZON-WIDERA-2021-ACCESS-03, under the grant agreement for project 101079051 - IPPT_TWINN. The research was done under the scope of the Project no. RRF-2.3.1-21-2022-00009, entitled "National Laboratory for Renewable Energy" which has been implemented with the support provided by the Recovery and Resilience Facility of the European Union within the framework of Programme Szechenyi Plan Plus. Project no. TKP-6-6/PALY-2021 has been implemented with the support provided by the Ministry of Culture and Innovation of Hungary from the National Research, Development and Innovation Fund, financed under the TKP2021-NVA funding scheme. AB - Polymer materials are getting more and more attention in key industries like the automotive, aerospace, and electrical industries. A long lifetime with sustainable recycling is expected; great results are possible thanks to modern material engineering. Finding a suitable material for the purpose and the appropriate methods to test the required functionality is essential. An important mechanical loading tests is the tensile test. Although the ISO 527-1:2019 standard uses different tensile specimen geometries, none of those consider the possible thickness variations of the injection molded parts. If thickness is reduced to 1 mm, the solid layer will be dominant, which makes the properties of the tensile specimen process-dependent instead of material-dependent. In today's industry, it is crucial to examine both the material and the details of the processing technology together, given the downsizing effect. LA - English DB - MTMT ER - TY - JOUR AU - Kiss-Nagy, Krisztián AU - Simongáti, Győző AU - Ficzere, Péter TI - Investigation of 3D Printed Underwater Thruster Propellers Using CFD and Structural Simulations JF - PERIODICA POLYTECHNICA-MECHANICAL ENGINEERING J2 - PERIOD POLYTECH MECH ENG VL - 68 PY - 2024 IS - 1 SP - 70 EP - 77 PG - 8 SN - 0324-6051 DO - 10.3311/PPme.23795 UR - https://m2.mtmt.hu/api/publication/34569161 ID - 34569161 N1 - Funding Agency and Grant Number: Department of Aeronautics and Naval Architecture Funding text: Acknowledgement The Department of Aeronautics and Naval Architecture supports the project presented in this article. AB - Unmanned Surface Vehicles (USV) and Autonomous or Remotely Operated Underwater vehicles (AUV, ROV) are developing and spreading rapidly in various industries. A common feature of these vehicles is that they are propelled by small plastic (or metal) propellers in most cases. Additive manufacturing can offer an excellent opportunity for rapid prototyping and the development of new models. This paper aims to investigate the fundamental aspects to be considered in the geometric design and manufacturing of small (diameter less than 100 mm) PLA (Polylactic acid) propellers 3D-printed using Fused Filament Fabrication (FFF) technology. In-service deformation of 3D-printed PLA ducted propellers with average geometry was investigated to determine the effect on the thrust and torque on the blades. For this purpose, one-directional FSI (Fluid Solid Interaction) simulations were performed using CFD (Computational Fluid Dynamics) and structural simulations. The propeller CAD geometries were generated using an in-house MATLAB script. The variable parameters of each version are the thickness, skew, and rake of the propeller blades. For the structural simulations, it was considered that the material properties of PLA parts printed with FFF technology depend on the print orientation. The results of the simulations show that except for extreme geometries (e.g., thin blades, skew, or rake more than 10 degrees), the deformation of small PLA ducted propellers is not significant. CFD studies of the deformed geometries have shown that the resulting deformation has no significant effect on the thrust and torque of the propeller and thruster. LA - English DB - MTMT ER - TY - JOUR AU - Pados, Gábor AU - Kemény, Alexandra AU - Károly, Dóra AU - Orbulov, Imre Norbert TI - Investigation of the Bending Properties of Ex situ Functional Metal Foams JF - PERIODICA POLYTECHNICA-MECHANICAL ENGINEERING J2 - PERIOD POLYTECH MECH ENG VL - 68 PY - 2024 IS - 1 SP - 63 EP - 69 PG - 7 SN - 0324-6051 DO - 10.3311/PPme.23707 UR - https://m2.mtmt.hu/api/publication/34531765 ID - 34531765 N1 - Funding Agency and Grant Number: Ministry of Culture and Innovation of Hungary from the National Research, Development and Innovation Fund [TKP-6-6/PALY-2021]; New National Excellence Program of the Ministry for Culture and Innovation from the National Research, Development and Innovation Fund; National Research, Development and Innovation Office (NKFIH); [OTKA-FK_21 138505]; [UNKP-23-2-I-BME-180] Funding text: Project no. TKP-6-6/PALY-2021 has been implemented with the support provided by the Ministry of Culture and Innovation of Hungary from the National Research, Development and Innovation Fund, financed under the TKP2021-NVA funding scheme. G. Pados was supported by the UNKP-23-2-I-BME-180 New National Excellence Program of the Ministry for Culture and Innovation from the source of the National Research, Development and Innovation Fund. This work was partially supported by the National Research, Development and Innovation Office (NKFIH) , under grant agreement OTKA-FK_21 138505. AB - In each industry, compromises have to be made when choosing materials. Lower-density materials have a significant advantage in the automotive sector, especially due to rising fuel prices, since weight reduction can lower overall fuel consumption. The advantageous properties of metal foams, such as low density, high specific strength, and excellent energy absorption, should be researched and exploited in as many areas and ways as possible. This research aims to perform and evaluate the bending tests of ex situ functional metal foams: aluminum alloy matrix (AlSi7Mg) was used, which was filled with Ø2.5–3.0 mm lightweight expanded clay aggregate particles and surrounded by thin-walled aluminum tubes (AlMgSi0.5) with a wall thickness of 2 mm and an outer diameter of Ø32 mm. Empty tubes, foam-filled tubes (with and without structural epoxy adhesive) and metal matrix syntactic foams were compared based on their flexural strength and energy absorption capacity. Quasi-static three-point bend tests were carried out up to 25 mm deflection. The foam-filled tubes with epoxy adhesive showed an average of 6% increase in flexural strength compared to the foam-filled tubes without adhesive and a 145% increase compared to the metal matrix syntactic foams. LA - English DB - MTMT ER - TY - JOUR AU - Papp, Bálint AU - Kristóf, Gergely TI - Predicting Concentration Fluctuations of Locally Emitted Air Pollutants in Urban-like Geometry Using Deep Learning JF - PERIODICA POLYTECHNICA-MECHANICAL ENGINEERING J2 - PERIOD POLYTECH MECH ENG VL - 68 PY - 2024 IS - 1 SP - 44 EP - 52 PG - 9 SN - 0324-6051 DO - 10.3311/PPme.23391 UR - https://m2.mtmt.hu/api/publication/34495646 ID - 34495646 N1 - Funding Agency and Grant Number: Ministry of Culture and Innovation of Hungary from the National Research, Development and Innovation Fund [TKP-6-6/PALY-2021, TKP2021-NVA]; New National Excellence Program of the Ministry for Culture and Innovation from the source of the National Research, Development and Innovation Fund [UNKP-22-3-II-BME-109]; Gedeon Richter Talent Foundation Funding text: Project no. TKP-6-6/PALY-2021 has been implemented with the support provided by the Ministry of Culture and Innovation of Hungary from the National Research, Development and Innovation Fund, financed under the TKP2021-NVA funding scheme. Balint Papp's contribution to this paper was supported by the UNKP-22-3-II-BME-109 New National Excellence Program of the Ministry for Culture and Innovation from the source of the National Research, Development and Innovation Fund; as well as by the Gedeon Richter Talent Foundation (registered office: Gyoemroi ut 19-21, 1103 Budapest, Hungary) , established by Gedeon Richter Plc., within the framework of the Gedeon Richter PhD Scholarship. AB - The accurate quantification of concentration fluctuations is crucial when evaluating the exposure to toxic, infectious, reactive, flammable, or explosive substances, as well as for the estimation of odor nuisance. However, in the field of Computational Fluid Dynamics (CFD), the industry currently relies predominantly on steady-state RANS turbulence models for simulating near-field pollutant dispersion, which are only capable of producing the time-averaged concentration field. This paper presents a regression relationship for calculating the standard deviation of the local concentration based on the mean concentration and the downstream distance from a point source, over a city-like surface, in the case of the wind direction perpendicular to the streets. The desired peak values and other statistical characteristics can be predicted by assuming a gamma distribution which is fitted based on the average and standard deviation. To obtain the regression function, a deep neural network model was used. The model was trained using time-resolved concentration data obtained from wind tunnel experiments. The validation results show that the concentration fluctuations predicted by the DNN-based model are in satisfactory agreement with the measurement data in terms of the skewness, the kurtosis, the median, and the peak concentrations. Furthermore, the present paper suggests a workflow for estimating the concentration fluctuations based on RANS CFD results, as well as recommendations for generating further training data for specific applications. LA - English DB - MTMT ER - TY - JOUR AU - Berecz, Tibor AU - Mészáros, István AU - Jenei, Péter TI - Investigation of Spinodal Decomposition in Isothermally Heat Treated LDX 2101 type Duplex Stainless Steel at 475 °C JF - PERIODICA POLYTECHNICA-MECHANICAL ENGINEERING J2 - PERIOD POLYTECH MECH ENG VL - 68 PY - 2024 IS - 1 SP - 38 EP - 43 PG - 6 SN - 0324-6051 DO - 10.3311/PPme.23385 UR - https://m2.mtmt.hu/api/publication/34273364 ID - 34273364 N1 - Department of Materials Science and Engineering, Faculty of Mechanical Engineering, Budapest University of Technology and Economics, Műegyetem rkp. 3., Budapest, H-1111, Hungary Department of Materials Physics, Faculty of Science, Eötvös Loránd University, Pázmány Péter sétány 1/a., Budapest, H-1117, Hungary Export Date: 4 March 2024 CODEN: PPMMB Correspondence Address: Berecz, T.; Department of Materials Science and Engineering, Műegyetem rkp. 3., Hungary; email: berecz.tibor@gpk.bme.hu Funding details: Magyar Tudományos Akadémia, MTA, BO/00821/20/6 Funding text 1: This research was supported by the János Bolyai Research Scholarship of the Hungarian Academy of Sciences, grant number: BO/00821/20/6. LA - English DB - MTMT ER - TY - JOUR AU - Kovács, Péter Zoltán TI - Joining of EN AW 6060 Pipes by Plastic Forming JF - PERIODICA POLYTECHNICA-MECHANICAL ENGINEERING J2 - PERIOD POLYTECH MECH ENG VL - 2023 PY - 2023 SP - 1 EP - 7 PG - 7 SN - 0324-6051 DO - 10.3311/PPme.23005 UR - https://m2.mtmt.hu/api/publication/34454253 ID - 34454253 AB - The article deals with an innovative, but not widely used type of joining of aluminum pipes through experiments. The joints are formed by plastic forming. The process is carried out in one step using the principle of pipe expansion, in order to bring the mating surfaces of the two pipes into a suitable position for the subsequent joining, which is created by means of plastic instability and simultaneous pressure flanging. Experimental tests were carried out with the tools designed to create most suitable joints. The length of the plastically formed pipe sections involved in the joint, the angle of the sharpened pipe ends, and the thickness of the formed joints were analyzed. One of the main goals of this study is to determine the proper joining parameters, such as tool distance or edge tapering for further investigations. As per the test results, it can be stated that the technology is suitable for joining aluminum tubes in a cost-effective way, and based on the promising strength results, further investigations will be conducted. LA - English DB - MTMT ER - TY - JOUR AU - Gunaraj, Lawrance AU - Paul, Sam AU - Mohammed, Jazeel AU - Sudhagar, Edwin AU - Thankachan, Titus TI - Optimization of Cutting Parameters for Hard Boring of AISI 4340 Steel Using Signal-to-Noise Ratio, Grey Relation Analysis and Analysis of Variance JF - PERIODICA POLYTECHNICA-MECHANICAL ENGINEERING J2 - PERIOD POLYTECH MECH ENG VL - ONLINE FIRST PY - 2023 SN - 0324-6051 DO - 10.3311/PPme.21729 UR - https://m2.mtmt.hu/api/publication/34155427 ID - 34155427 AB - Tool vibration in the boring process is the main concern because of the tool overhanging which leads to high tool wear, cutting force and cutting temperature. Interaction between machine dynamics and the metal cutting operation tool also results in tool vibration. The optimized cutting parameters will able to decrease tool vibration and in turn, increase the productivity in the manufacturing sector. In this study, statistical mathematical approaches to develop models for determining the impact of individual cutting parameters on cutting temperature, tool wear, cutting force, and tool vibration when hard boring AISI 4340 steels. During hard boring of AISI 4340 steel, the current investigation consisted of 27 run trials with three varying levels of cutting velocity, feed rate, and depth of cut and each of these variables was tested at three different levels. This work intends to simultaneous optimize statistical analysis such as Signal-to-Noise (S/N) ratio, Analysis of Variance (ANOVA) and Grey Relational Analysis (GRA). ANOVA and S/N ratio is used to identify the important cutting parameters on the single response optimization and GRA is used to optimize the multi-response optimization technique on cutting parameters. The results shows that both single and multi-response optimization technique shows the same optimized cutting parameter. LA - English DB - MTMT ER - TY - JOUR AU - Gyürki, Dániel László AU - Paál, György TI - Investigating Particle Paths in Intracranial Aneurysms: A Parametric Study JF - PERIODICA POLYTECHNICA-MECHANICAL ENGINEERING J2 - PERIOD POLYTECH MECH ENG VL - 67 PY - 2023 IS - 4 SP - 350 EP - 360 PG - 11 SN - 0324-6051 DO - 10.3311/PPme.23482 UR - https://m2.mtmt.hu/api/publication/34425236 ID - 34425236 N1 - Funding Agency and Grant Number: National Brain Research Program [2017-1.2.1-NAP-2017-00002]; National Research, Development, and Innovation Fund of Hungary [TKP2021-EGA-02] Funding text: This research was supported by the National Brain Research Program under the Contract Number 2017-1.2.1-NAP-2017-00002, and by the National Research, Development, and Innovation Fund of Hungary under Grant TKP2021-EGA-02. AB - A large part of computational fluid dynamics (CFD) studies in hemodynamics concentrates on the berry-like bulgings on cerebral vessel walls, called intracranial aneurysms (IA). One technique is the calculation of particle paths, which can help understand important physiological processes like thrombus formation or drug propagation. The problem is that the particle paths can display chaotic nature even in simple flows, thus, investigating the effects of parameters on the particle paths is essential. The method used in this study consists of four steps. The first step is to voxelize the observed domain into a uniform voxel grid, the second step is to simulate the velocity flow field using the lattice-Boltzmann method, then to calculate one million particle paths using a fourth-order RungeKutta integrator. Lastly, the final step is the calculation of the relative perimeter, relative area and their ratio (P/A ratio) for each outlet when the particle release plane is colored according to the outlets the particles took. Five patient-specific cases were investigated. After a voxel size and integrator time step dependence study, the effect of the presence of the aneurysm sack and the particle release time within the heart cycle were assessed. Based on five geometries, the presence of the aneurysm sac increases the P/A ratio (which is a direct link to the chaotic nature of the particle paths), and when the particles are released near the peak and the decelerating phase of the heart cycle, the P/A ratio also significantly increases. LA - English DB - MTMT ER - TY - JOUR AU - Dobra, Péter AU - Jósvai, János TI - Overall Equipment Effectiveness Prediction with Multiple Linear Regression for Semi-automatic Automotive Assembly Lines JF - PERIODICA POLYTECHNICA-MECHANICAL ENGINEERING J2 - PERIOD POLYTECH MECH ENG VL - 67 PY - 2023 IS - 4 SP - 270 EP - 275 PG - 6 SN - 0324-6051 DO - 10.3311/PPme.22302 UR - https://m2.mtmt.hu/api/publication/34399907 ID - 34399907 AB - In the field of industry, especially in the production areas, it is particularly important that the monitoring of assembly efficiency takes place in real-time mode, and that the related data-based estimation also works quickly and reliably. The Manufacturing Execution System (MES), Enterprise Resource Planning (ERP) and Customer Relationship Management (CRM) systems used by companies provide excellent support in data recording, processes, and storing. For Overall Equipment Effectiveness (OEE) data showing the efficiency of assembly lines, there is a regular need to determine expected values. This paper focuses on OEE values prediction with Multiple Linear Regression (MLR) as supervised machine learning. Many factors affecting OEE (e.g., downtimes, cycle time) are examined and analyzed in order to make a more accurate estimation. Based on real industrial data, we used four different methods to perform prediction with various machine learning algorithms, these were the cumulative, fix rolling horizon, optimal rolling horizon and combined techniques. Each method is evaluated based on similar mathematical formulas. LA - English DB - MTMT ER -