TY - JOUR AU - Döbrentei, Sándor AU - Váradi, Károly TI - Végeselem környezetben definiált mozgó hőforrás analitikus validálása JF - GÉP J2 - GÉP VL - 74 PY - 2023 IS - 4 SP - 53 EP - 56 PG - 4 SN - 0016-8572 UR - https://m2.mtmt.hu/api/publication/34394297 ID - 34394297 LA - Hungarian DB - MTMT ER - TY - JOUR AU - Szabó, Gyula AU - Váradi, Károly TI - FE micromodel of a cord-rubber composite tube sample subjected to uniaxial tension JF - JOURNAL OF REINFORCED PLASTICS AND COMPOSITES J2 - J REINF PLAST COMP VL - 42 PY - 2023 IS - 9-10 SP - 393 EP - 404 PG - 12 SN - 0731-6844 DO - 10.1177/07316844221100269 UR - https://m2.mtmt.hu/api/publication/33711978 ID - 33711978 AB - The aim of this study is to examine displacements, strains and stresses of a railway composite cord-rubber air brake tube undergoing uniaxial tension by microscale modelling. LA - English DB - MTMT ER - TY - JOUR AU - Szabó, Gyula AU - Váradi, Károly TI - FE Micromodel of a Cord-rubber Composite Test Specimen Subjected to Uniaxial Tension JF - PERIODICA POLYTECHNICA-MECHANICAL ENGINEERING J2 - PERIOD POLYTECH MECH ENG VL - 66 PY - 2022 IS - 4 SP - 325 EP - 335 PG - 11 SN - 0324-6051 DO - 10.3311/PPme.20363 UR - https://m2.mtmt.hu/api/publication/33050251 ID - 33050251 N1 - Funding Agency and Grant Number: Ministry of Innovation and Technology of Hungary from the National Research, Development and Innovation Fund [TKP2021] Funding text: Acknowledgement The research reported in this paper is part of project no. BME-NVA-02, implemented with the support provided by the Ministry of Innovation and Technology of Hungary from the National Research, Development and Innovation Fund, financed under the TKP2021 funding scheme. AB - The aim of this study is to examine displacements, strains and stresses as well as to predict possible failure mechanisms arising at the yarn-matrix level of a test specimen of a railway composite cord-rubber air brake tube undergoing uniaxial tension by microscale modelling. Furthermore, this paper also aims to verify the material properties of the micromodel of the test specimen. The micromodel is based on macromodels (by matching the boundary conditions of the micromodels with displacements of the macromodels) created previously by authors of this article. The reinforcing yarns are described by an orthotropic, elastic material model, whereas the matrix has been described by a 2 parameter Mooney-Rivlin model, which all have been validated before by a uniaxial tensile test and a three-point bending test. Force-displacement curves of the micromodel and experimental results show a considerably good agreement. Yarns have a less dominant role in the load transfer mechanism of the reinforcement layers, because of the short-yarn reinforced nature of the specimen. Shear strains are high at free yarn ends marking the possible locations of failure initiation in debonding in the shear mechanism of the reinforcement layers. High shear strain values imply that the dominant mode of load transfer is shear in the matrix in the reinforcement layers. LA - English DB - MTMT ER - TY - CHAP AU - Szabó, Gyula AU - Váradi, Károly ED - Al-Begain, Khalid ED - Iacono, Mauro ED - Campanile, Lelio ED - Bargiela, Andrzej TI - FE model of a cord-rubber railway brake tube subjected to extreme operational loads on a reverse curve test track T2 - Proceedings of the 35th ECMS International Conference on Modelling and Simulation ECMS 2021 PB - European Council for Modelling and Simulation (ECMS) CY - Kingston Upon Thames CY - Dudweiler SN - 9783937436739 T3 - Communications of the ECMS, ISSN 2522-2414 ; 35 Issue 1. PY - 2021 SP - 139 EP - 146 PG - 8 UR - https://m2.mtmt.hu/api/publication/32888991 ID - 32888991 N1 - Kuwait College of Science and Technology Correspondence Address: Szabó, G.; Department of Machine and Product Design, 1-3 Műegyetem rkp., Hungary; email: szabo.gyula@gt3.bme.hu Funding details: Nemzeti Kutatási, Fejlesztési és Innovaciós Alap, NKFIA Funding details: Innovációs és Technológiai Minisztérium Funding text 1: Authors would like to express their gratitude to Dr. Attila Piros, Department of Machine and Product Design at the Budapest University of Technology and Economics for his valuable help regarding the formulation of the kinematic model. Authors are also extremely grateful to MÁV Central Rail and Track Inspection Ltd., namely to Csaba Pálfi, for providing them with test report 7420007-19/VÜE-1VJ-1.0-EN. The research reported in this paper and carried out at BME has been supported by the NRDI Fund (TKP2020 NC, Grant No. BME-NCS) based on the charter of bolster issued by the NRDI Office under the auspices of the Ministry for Innovation and Technology. AB - In certain cases, rolling stocks and railway vehicle components, i.e. brake tubes need to operate under extreme conditions such as at sub-zero temperature (e.g. -40°C) and on a reverse curve track, when displacements of the suspension points of the tubes cause large deformations in tubes. In this paper, displacements of the suspension points of the tubes are determined by a kinematic model validated by a draw and buffing gear test [1]. Afterwards, FE simulation has been carried out at minimum and maximum suspension point distance based on these displacements for the investigation of stress, strain states and possible failure considering the case of internal pressure and no internal pressure. Equivalent strain, stress and Tsai-Hill failure indices are much below the criterial values, so failure is not probable. The straight section between the curves of opposite curvatures reduces deformation in tubes in the critical positions leading to lower strain, stress and failure index values. © ECMS Khalid Al-Begain, Mauro Iacono, Lelio Campanile, Andrzej Bargiela (Editors) LA - English DB - MTMT ER - TY - CHAP AU - Szabó, Gyula AU - Váradi, Károly ED - Iacono, Mauro ED - Palmieri, Francesco ED - Gribaudo, Marco ED - Ficco, Massimo TI - FE Simulation Of A Cord-Rubber Composite Tube Subjected To Bending Due To Operational Loads On A Railroad Reverse Curve With Extremely Low Curve Radius At Sub-Zero Temperature T2 - Proceedings of the 33rd International ECMS Conference on Modelling and Simulation PB - European Council for Modelling and Simulation (ECMS) CY - Wilhelmshaven SN - 9783937436654 T3 - Communications of the ECMS, ISSN 2522-2414 ; 33. PY - 2019 SP - 377 EP - 383 PG - 7 DO - 10.7148/2019-0377 UR - https://m2.mtmt.hu/api/publication/32888455 ID - 32888455 LA - English DB - MTMT ER - TY - JOUR AU - Kocsis, András Bernát AU - Váradi, Károly AU - Szalai, Gabor AU - Kovacs, Tamas AU - Bodzay, Tamás TI - Hybrid solution combining osteosynthesis and endoprosthesis for double column acetabular fractures in the elderly provide more stability with finite element model JF - EKLEM HASTALIKLAN VE CERRAHISI - JOINT DISEASES AND RELATED SURGERY J2 - EKLEM HAST CERRAHISI VL - 30 PY - 2019 IS - 2 SP - 106 EP - 111 PG - 6 SN - 1305-8282 DO - 10.5606/ehc.2019.66592 UR - https://m2.mtmt.hu/api/publication/31082962 ID - 31082962 AB - Objectives: This study aims to compare mechanical stability of osteosynthesis (plate and screw fixation) alone versus the same method supplemented with hip arthroplasty (hybrid solution) for double column fractures in elderly.Patients and methods: Mechanical investigations were performed on an advanced finite element pelvis model developed for double column fractures. The following simulated implant combinations were analyzed: modular acetabular basket with a ring with polyaxial screws and U-plate; plates with polyaxial screws placed on the medial-horizontal (linea terminalis) and quadrilateral bone surfaces; modular acetabular cup with U-plates; and polyaxial screws in sizes optimized based on a finite element model (FEM). Using the models, the possible shifts in peak load positions arising in different movement patterns caused by load and tension and implant deformation were measured.Results: Hybrid systems resulted in minimal deformation of the implants already available on the market. We observed less possible shifts and greater stability in the acetabular fracture zones, compared to conventional osteosynthesis alone. Optimization with available and compatible implant sizes led to a further significant increase in stability.Conclusion: Hybrid method combining osteosynthesis and prosthesis implantation provide more stability in biomechanical models in the treatment of double column fractures in elderly. LA - English DB - MTMT ER - TY - JOUR AU - Szabó, Gyula AU - Váradi, Károly TI - Instability analysis of a filament-wound composite tube subjected to compression/bending JF - ADVANCED COMPOSITES LETTERS J2 - ADV COMPOS LETT VL - 28 PY - 2019 SP - 1 EP - 13 PG - 13 SN - 0963-6935 DO - 10.1177/0963693519877417 UR - https://m2.mtmt.hu/api/publication/31008678 ID - 31008678 LA - English DB - MTMT ER - TY - JOUR AU - Váradi, Károly AU - Szabó, Gyula TI - Összenyomásnak és hajlításnak kitett száltekercselt kompozit tömlő instabilitási vizsgálata JF - GÉP J2 - GÉP VL - 70 PY - 2019 IS - 4 SP - 25 EP - 30 PG - 6 SN - 0016-8572 UR - https://m2.mtmt.hu/api/publication/30906167 ID - 30906167 LA - Hungarian DB - MTMT ER - TY - CONF AU - Gróza, Márton György AU - Nadot, Yves AU - Váradi, Károly ED - Hénaff, G. TI - Fatigue design of cast iron components with surface discontinuities T2 - 12th International Fatigue Congress (FATIGUE 2018) T3 - MATEC Web of Conferences, ISSN 2261-236X ; 165. PY - 2018 PG - 6 DO - 10.1051/matecconf/201816510010 UR - https://m2.mtmt.hu/api/publication/30800880 ID - 30800880 LA - English DB - MTMT ER - TY - JOUR AU - Szabó, Gyula AU - Váradi, Károly TI - Uniaxial Tension of a Filament-wound Composite Tube at Low Temperature JF - ACTA TECHNICA JAURINENSIS J2 - ACTA TECH JAURIN VL - 11 PY - 2018 IS - 2 SP - 84 EP - 103 PG - 20 SN - 1789-6932 DO - 10.14513/actatechjaur.v11.n2.456 UR - https://m2.mtmt.hu/api/publication/30715211 ID - 30715211 LA - English DB - MTMT ER -