Статті в журналах: "Assemblies vibrations"

1

Verma, V., D. Chionis, A. Dokhane, and H. Ferroukhi. "MODELLING AND ANALYSIS OF FUEL ASSEMBLY VIBRATIONAL MODES IN PWRS USING SIMULATE-3K." EPJ Web of Conferences 247 (2021): 21008. http://dx.doi.org/10.1051/epjconf/202124721008.

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Some of the KWU pre-KONVOI PWRs operating across Europe saw a systematic increase in the neutron noise levels over several cycles in the last decade, and subsequently, core internals’ movements, especially vibrations of fuel assemblies with specific designs were identified as one of the plausible causes. Therefore, it is important to develop computational methods that can allow to investigate and predict the reactor noise response to fuel assemblies vibrations. To this aim, the 3D nodal reactor dynamics code SIMULATE-3K is used at PSI with a special module called the ‘assembly vibration model’ that imitates time-dependent motions of fuel assemblies by dynamically modifying the water-gaps surrounding the laterally moving fuel assemblies. The varying water-gaps are represented by the variation in the corresponding two-group macroscopic cross sections generated using the lattice code CASMO-5 in 2D. The studies conducted so far to assess the methodology for full core noise simulations were based on assuming vibrations of a clamped-free cluster of fuel assemblies that are unsupported from both ends. However, as this represents a non-physical movement, further developments were made at PSI to allow simulating more realistic movements of fuel assemblies such as the cantilevered mode vibration. The updated methodology, along with evaluations of the simulated noise response to realistic vibration modes, is presented in this paper. Results show that, as expected, the radial and axial neutron noise behaviour follow the vibration pattern of the imposed time-dependent axial functions corresponding to the natural oscillation modes of the fuel assemblies, thereby providing confidence in the application of the developed methodology for numerical neutron noise analyses of the PWR cores.

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2

Aadnoy, Bernt Sigve. "Transversal Vibrations in Stabilized Drilling Assemblies." Energy Sources 8, no. 4 (January 1986): 305–29. http://dx.doi.org/10.1080/00908318608946059.

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3

Avramov, K. V., and J. Awrejcewicz. "Localization of Vibrations in Blade Assemblies." Journal of Vibration and Control 16, no. 11 (May 21, 2010): 1605–22. http://dx.doi.org/10.1177/1077546309103258.

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4

Holmes, R., and J. E. H. Sykes. "Large-amplitude vibrations in rotor assemblies." Journal of Sound and Vibration 133, no. 2 (September 1989): 337–51. http://dx.doi.org/10.1016/0022-460x(89)90930-9.

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5

Sharma, Gaurav, Adepu Kumaraswamy, and Sangram Rath. "Enhancing Structural Vibration Damping in Marine Machinery: A Comprehensive Numerical Investigation with Modal and Harmonic Analysis." Applied Mechanics and Materials 921 (April 26, 2024): 39–56. http://dx.doi.org/10.4028/p-mrpje3.

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This article presents a comprehensive study on the damping of vibrations in a motor-pump assembly using viscoelastic and constrained layer damping treatments. The assembly's structural model, designed using SolidWorks software, is subjected to modal and harmonic analyses in ANSYS. The primary goal is to mitigate vibration amplitudes originating from the motor and pump to enhance the assembly's operational performance. Three damping treatments are investigated: Free Layer Damping (FLD), Sandwich Constrained Layer Damping (CLD), and a novel Multilayer CLD approach. The viscoelastic material is modeled using the Prony series method, and its properties are incorporated into the finite element analysis Results demonstrate that the application of damping treatments significantly reduces vibration amplitudes compared to the untreated structure. Among the treatments, the Multilayer CLD approach exhibits the highest damping efficiency, reducing the maximum amplitude by approximately 52% compared to the base structure. The study showcases the advantages of utilizing viscoelastic and constrained layer damping techniques for enhancing vibration control and operational stability in industrial assemblies. The research findings contribute to the field of structural dynamics and vibration control, offering valuable insights into the design and optimization of mechanical systems subjected to dynamic loads. This study opens avenues for further research and practical applications aimed at improving the performance and reliability of motor-pump assemblies and similar industrial equipment.

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6

Зиньковский, Анатолий Павлович, Анатолий Леонидович Стельмах та Сергей Николаевич Кабанник. "РЕЗУЛЬТАТЫ ОЦЕНКИ ДИНАМИЧЕСКОЙ УСТОЙЧИВОСТИ К ДОЗВУКОВОМУ ФЛАТТЕРУ ЛОПАТОЧНЫХ ВЕНЦОВ КОМПРЕССОРОВ НЕКОТОРЫХ АВИАЦИОННЫХ ГАЗОТУРБИННЫХ ДВИГАТЕЛЕЙ". Aerospace technic and technology, № 8 (31 серпня 2019): 78–84. http://dx.doi.org/10.32620/aktt.2019.8.12.

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The paper outlines the results of the investigation on the verification of the express method of prediction of dynamic stability for subsonic flutter using the blade assemblies of individual stages of the compressor of some types of aircraft gas-turbine engines at different modes of their operation. The paper gives a brief overview of the basic concepts of the developed express estimation method, possibilities of the determination of the stability limit for the blade assemblies for a subsonic flutter, as well as the results of the assessment of the dynamic stability of the compressor stages of some modern aircraft gas-turbine engines. Firstly, the reduced frequencies of vibrations of the blade assemblies under investigation and their critical values coincide practically. The mentioned critical values were determined from the test data for the straight cascades of the blade airfoils corresponding to two sections of the height of the blade airfoil portion. Hence it follows that the task can be solved employing only gas-dynamic parameters of the flow for one of the sections of the airfoil within the specified range of its height. Secondly, the prediction of dynamic stability for the subsonic flutter of the blade assemblies of separate compressor stages of some types of aircraft gas-turbine engines and the comparison of the obtained results with the data of bench tests, as well as the data obtained using other methods, were made. It was implied that the developed method allows one to determine the flutter limit with high accuracy, as well as make an optimal selection of the values of the reduced frequency of the blade vibrations for the specified range of the angle of attack of the sections of the blade assemblies upon the condition of its occurrence. Thirdly, the possibility to determine the nature of vibration excitation for the blade assemblies is considered using the analysis of the initiation of cracks in the blade root of the first compressor stage of the high-pressure gas-turbine engine. Moreover, it is shown that at large angles of attack (≥ 10°) an insignificant displacement of the dynamic stability limit of the blade assemblies may occur in the direction of large values of the reduced frequency of their vibrations.

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7

Białas, Katarzyna. "Passive and Active Elements in Reduction of Vibrations of Torsional Systems." Solid State Phenomena 164 (June 2010): 260–64. http://dx.doi.org/10.4028/www.scientific.net/ssp.164.260.

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The adverse effects of vibrations on the performance of machines and their environment are the subject of various studies. That is why already in the machine design stage the designers have to face the problem of preventing undesirable effects in the functioning of new machines as well as adapting complete machines to the requirements resulting from the current knowledge on hazards caused by these machines. There are a number of methods for preventing excessive vibrations, which have an impact on machine sub-assemblies and elements. In particular, the passive, semi-active and active vibration-reducing systems can be distinguished [4,5].

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8

Viebach, M., C. Lange, M. Seidl, Y. Bilodid, and A. Hurtado. "NEUTRON NOISE PATTERNS FROM COUPLED FUEL-ASSEMBLY VIBRATIONS." EPJ Web of Conferences 247 (2021): 02015. http://dx.doi.org/10.1051/epjconf/202124702015.

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The neutron flux fluctuation magnitude of KWU-built PWRs shows a hitherto unexplained correlation with the types of loaded fuel assemblies. Also, certain measured long-range neutron flux fluctuation patterns in neighboring core quadrants still lack a closed understanding of their origin. The explanation of these phenomena has recently revived a new interest in neutron noise research. The contribution at hand investigates the idea that a synchronized coolant-driven vibration of major parts of the fuel-assembly ensemble leads to these phenomena. Starting with an assumed mode of such collective vibration, the resulting effects on the time-dependent neutron-flux distribution are analyzed via a DYN3D simulation. A three-dimensional representation of the time-dependent bow of all fuel assemblies is taken into account as a nodal DYN3D feedback parameter by time-dependent variations of the fuel-assembly pitch. The impact of its variation on the cross sections is quantiﬁed using a cross-section library that is generated from the output of corresponding CASMO5 calculations. The DYN3D simulation qualitatively reproduces the measured neutron-flux fluctuation patterns. The magnitude of the fluctuations and its radial dependence are comparable to the measured details. The results imply that collective fuel-assembly vibrations are a promising candidate for being the key to understand long-known fluctuation patterns in KWU built PWRs. Further research should elaborate on possible excitation mechanisms of the assumed vibration modes.

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9

Hemingway, N. G. "Modelling Vibration Transmission Through Coupled Vehicle Sub-Systems Using Mobility Matrices." Proceedings of the Institution of Mechanical Engineers, Part D: Transport Engineering 200, no. 2 (April 1986): 125–34. http://dx.doi.org/10.1243/pime_proc_1986_200_172_02.

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This paper indicates how vibration responses of a vehicle body produced by inputs at the rear wheels were modelled using a mobility matrix coupling method. The model simulates the multiple coupling of the sub-assemblies comprising the rear axle, rear suspension and vehicle body in the lower audio-frequency range. Such a model is useful when investigating the transmission paths along which vibrations travel into the vehicle body, subsequently generating internal noise.

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10

Planchard, J. "Vibrations of nuclear fuel assemblies: A simplified model." Nuclear Engineering and Design 86, no. 3 (June 1985): 383–91. http://dx.doi.org/10.1016/0029-5493(85)90303-6.

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11

MEAD, D. J. "FREE VIBRATIONS OF SELF-STRAINED ASSEMBLIES OF BEAMS." Journal of Sound and Vibration 249, no. 1 (January 2002): 101–27. http://dx.doi.org/10.1006/jsvi.2001.3830.

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12

Diroll, Benjamin T., Vladislav Kamysbayev, Igor Coropceanu, Dmitri V. Talapin, and Richard D. Schaller. "Heat-driven acoustic phonons in lamellar nanoplatelet assemblies." Nanoscale 12, no. 17 (2020): 9661–68. http://dx.doi.org/10.1039/d0nr00695e.

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13

Mensa-Wilmot, Graham. "Technology Focus: Bits and Bottomhole Assemblies (December 2020)." Journal of Petroleum Technology 72, no. 12 (December 1, 2020): 52. http://dx.doi.org/10.2118/1220-0052-jpt.

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Achieving and sustaining performance drilling’s intended benefits - improved drilling efficiency with minimal down-hole tool failures and the associated reductions in project cycle time and operational costs - requires new protocols in drilling-system analysis. Drilling-system components [bits, reamers, bottomhole assemblies (BHAs), drive systems, drilling parameters, and hydraulics] must be analyzed independently for their relevance on the basis of application types and project challenges. Additionally, the drilling system must undergo holistic evaluations to establish functional compatibility and drilling-parameter responses and effects, considering project objectives and key performance indicators. This comprehensive physics-based approach ensures durability and rate-of-penetration (ROP) improvements without compromising stability and downhole tool reliability. The success of this process is strongly dependent on vibration control. Considering the different vibration modes - axial, torsional, lateral, stick/slip, and whirl - and their many dissimilar initiating and amplification factors, their sources always must be identified. Researchers have challenged the usual classification of erratic torque and revolution-rate behavior as stick/slip. BHA design and drilling-parameter ranges, considering blade spacing, can produce unfavorable tubular deformations, contact points, and side loads. This condition creates torque and revolution-rate fluctuations that have been linked to lateral vibrations. Awareness of these vibration modes, particularly their sources and intensifying conditions, ensures development of effective remediation solutions. Improved borehole quality, with regard to tortuosity and rugosity, must always be considered as a critical requirement in performance drilling. This condition reduces borehole drag, enhances drilling-parameter transfer, and improves ROP and overall run lengths. Most importantly, it reduces vibrations, leading to improvements in downhole tool life and directional drilling performance. In addition to formation drillability effects, drilling-systems components and operational practices have strong effects on borehole quality. Consequently, this must be part of the drilling-system analysis. The industry’s advancements at developing physics-based solutions for drilling challenges have matured. Continuing to ask questions that help us understand how and why we fail or succeed puts more wind beneath our wings to accelerate learning and reduce cycle times. Recommended additional reading at OnePetro: www.onepetro.org. SPE 200740 Digital Twins for Well Planning and Bit-Dull-Grade Prediction by Mehrdad Gharib Shirangi, Baker Hughes, et al. SPE 201616 Validating Bottomhole-Assembly Analysis Models With Real-Time Measurements for Improved Drilling Performance by Mark Smith, Premier Directional Drilling, et al. IADC/SPE 199658 Simulation and Measurement of High-Frequency Torsional Oscillation (HFTO)/High-Frequency Axial Oscillation and Downhole HFTO Mitigation: Knowledge Gains Continue by Using Embedded High-Frequency Drilling Dynamics Sensors by Junichi Sugiura, Sanvean Technologies, et al.

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14

Gildish, Eli, Michael Grebshtein, Yehudit Aperstein, Alex Kushnirski, and Igor Makienko. "Helicopter Bolt Loosening Monitoring using Vibrations and Machine Learning." PHM Society European Conference 7, no. 1 (June 29, 2022): 146–55. http://dx.doi.org/10.36001/phme.2022.v7i1.3322.

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The existing helicopter Health and Usage Management Systems (HUMS) collect and process flight operational parameters and sensors data such as vibrations to provide health monitoring of the helicopter dynamic assemblies and engines. So far, structure-related mechanical faults, such as looseness in bolted structures, have not been addressed by vibration-based condition monitoring in existing HUMS systems. Bolt loosening was identified as a potential risk to flight safety demanding periodical visual monitoring, and increased maintenance and repair expenses. Its automatic identification in helicopters by using vibration measurements is challenging due to the limited number of known events and the presence of high-energy vibrations originating in rotating parts, which shadow the low-level signals generated by the bolt loosening. New developed bolt loosening monitoring approach was tested on HUMS vibrations data recorded from the IAF AH-64 Apache helicopters fleet. ML-based unsupervised anomaly detection was utilized in order to address the limited number of faulty cases. The predictive power of health features was significantly improved by applying the Harmonic filtering differentiating between the high-energy vibrations generated by rotating parts compared with the low-energy structural vibrations. Different unsupervised anomaly detection techniques were examined on the dataset. The experimental results demonstrate that the developed approach enable successful bolt loosening monitoring in helicopters and can potentially be used in other health monitoring applications.

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15

Zinkovskii, Anatoliy, Kyrylo Savchenko, Yevheniia Onyshchenko, Leonid Polishchuk, Abilkaiyr Nazerke, and Bagashar Zhumazhanov. "FINITE ELEMENT MODEL FOR ANALYSIS OF CHARACTERISTICS OF SHROUDED ROTOR BLADE VIBRATIONS." Informatyka, Automatyka, Pomiary w Gospodarce i Ochronie Środowiska 12, no. 4 (December 30, 2022): 11–16. http://dx.doi.org/10.35784/iapgos.3264.

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The paper presents the approaches to FE modelling of blade airfoil, contact between the shrouds and operational damage. The regularities are established concerning the influence of the finite element type, finite element mesh and model of contact interaction on the spectrum of natural frequencies of blade assemblies. The use of the developed computational models is substantiated to determine the forced vibration characteristics of the selected objects of investigation. Based on the performed numerical experiments it was substantiated of finite element model selection for analysis of characteristics of shrouded rotor blade vibrations.

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16

Gallego-Garrido, J., G. Dimitriadis, and J. R. Wright. "A Class of Methods for the Analysis of Blade Tip Timing Data from Bladed Assemblies Undergoing Simultaneous Resonances—Part I: Theoretical Development." International Journal of Rotating Machinery 2007 (2007): 1–11. http://dx.doi.org/10.1155/2007/27247.

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Blade tip timing is a technique for the measurement of vibrations in rotating bladed assemblies. Although the fundamentals of the technique are simple, the analysis of data obtained in the presence of simultaneously occurring synchronous resonances is problematic. A class of autoregressive-based methods for the analysis of blade tip timing data from assemblies undergoing two simultaneous resonances has been developed. It includes approaches that assume both sinusoidal and general blade tip responses. The methods can handle both synchronous and asynchronous resonances. An exhaustive evaluation of the approaches was performed on simulated data in order to determine their accuracy and sensitivity. One of the techniques was found to perform best on asynchronous resonances and one on synchronous resonances. Both methods yielded very accurate vibration frequency estimates under all conditions of interest.

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17

Sokolski, Piotr. "Assessment of Suitability for Long-Term Operation of a Bucket Elevator: A Case Study." Energies 16, no. 23 (November 30, 2023): 7852. http://dx.doi.org/10.3390/en16237852.

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Bucket elevators generally operate on a 24/7 basis, and for this reason, one of the main requirements is their high reliability. This reliability can be ensured, among other things, by assessing the technical condition of drive assemblies and working assemblies and taking appropriate measures. Carrying out diagnostic measurements enables periodical monitoring of those mechanisms. Vibroacoustic methods are usually employed in operating conditions to measure vibration velocity and acceleration at specific points, and are used as diagnostic signals. This paper presents the results of tests of the intensity of vibrations generated in the drive unit of a large industrial bucket elevator. The analysis of the results in the time domain and frequency domain served as the basis for evaluating the suitability of the drive, and thus the elevator, for long-term operation.

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18

Olafsson, Sveinn V., and Efstratios Nikolaidis. "Random vibrations of bladed-disk assemblies under cyclostationary excitation." Journal of Propulsion and Power 7, no. 6 (November 1991): 981–89. http://dx.doi.org/10.2514/3.23417.

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19

Novac, Gheorghe, and Bogdan Novac. "Contributions Regarding the Use of Mechanical Vibrations in Order to Improve the Properties of Steels and Welded Joints Used in Metal Constructions." RECENT - REzultatele CErcetărilor Noastre Tehnice 21, no. 2 (November 19, 2020): 67–71. http://dx.doi.org/10.31926/recent.2020.61.067.

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The paper presents aspects regarding the influence of vibrations on the mechanical properties of welded joints, made with basic materials of Spanish and Romanian origin. In this research is presented the practical way to make the necessary assemblies for the proposed tests. The tests show that vibrations have a significant contribution to the quality of welded joints. This is explained by the appearance of several crystallization centres which makes the structure finer. By using vibrations, the atoms are rearranged in the structure, ensuring a proper de-tensioning. The stresses induced in welded metals are significantly reduced by the use of vibration during welding process. The addition materials have a significant contribution to the emergence of stresses in welded joints as well. These stresses can contribute to the appearance of microstructural constituents with significant hardness. The welding equipment and technologies used also have a significant contribution to the emergence of the remaining stresses. For example, the submerged arc welding technology (SAF) can introduce very high internal stresses. By using vibrations during the welding process, it is achieved a fine structure and a significant reduction of remaining stresses in the welded joints.

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20

Vintilescu, Alina, Jeremy Jallageas, Jean Yves K'Nevez, and Mehdi Chérif. "Optimizing the Drilling Process of Multi-Layer Materials Using Vibration Analysis." Applied Mechanics and Materials 325-326 (June 2013): 28–33. http://dx.doi.org/10.4028/www.scientific.net/amm.325-326.28.

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Composite in aircraft structures has become increasingly important and should represent approximately 50% in mass till 2012. During the structure assembly, in aerospace centres of production there are used pneumatic positive feed units (also called automatic drilling units). They are manually positioned on specific grids to drill the panels of structure (assemblies of composite materials, aluminium and titanium). This article compares vibration-assisted drilling and non-vibratory drilling and presents the advantages of using vibrations in the process. The conclusions will show the results obtained and the developments to be carried out in an immediate future. Keywords: multi-layer material, vibration assisted drilling, Campbell diagram.

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21

Datta, J., and K. Farhang. "A Nonlinear Model for Structural Vibrations in Rolling Element Bearings: Part II—Simulation and Results." Journal of Tribology 119, no. 2 (April 1, 1997): 323–31. http://dx.doi.org/10.1115/1.2833218.

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This is the second of two companions papers. In the first paper, “A Nonlinear Model for Structural Vibrations in Rolling Element Bearings: Part I—Derivation of Governing Equations,” equations governing the vibrational response of rolling element bearings were developed. The mathematical formulations are utilized in this paper to study a number of effects on bearing structural vibrations. These include the effects of relative size of roller and inner and outer races, and inertias of inner and outer race assemblies, i.e., inertia of the races plus the components of an external system to which the inner and outer races are attached; the load acting on the bearing, its magnitude and nature (i.e., whether linear, rotational etc.). The studies are made under constant operating conditions (speed, lubrication) and the results obtained are discussed.

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22

Wei, S. T., and C. Pierre. "Localization Phenomena in Mistuned Assemblies with Cyclic Symmetry Part II: Forced Vibrations." Journal of Vibration and Acoustics 110, no. 4 (October 1, 1988): 439–49. http://dx.doi.org/10.1115/1.3269548.

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The effects of disorder on the forced response of nearly periodic structures with cyclic symmetry are investigated. The force model adopted here is relevant to blade assemblies. Perturbation methods for the forced response are developed to gain a physical insight into the effects of mistuning. The study shows that the internal coupling between component systems is the key parameter governing the sensitivity to mistuning and that localized forced vibrations do occur in the disordered assembly for weak internal coupling. However, although both localized free and forced vibrations occur for finite or large values of the mistuning to coupling ratio, the deflection patterns for these two types of localized vibrations are different. Also, for the forced response, the degree of localization does not necessarily increase as this ratio increases—a fundamental difference from localized free modes. An important conclusion is that the common periodicity assumption for cyclic structures may lead to qualitative errors for the forced response of weakly coupled systems when small mistuning is present.

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23

Dostov, A. I. "Mechanism of the Excitation of Vibrations in RBMK Fuel Assemblies." Atomic Energy 96, no. 3 (March 2004): 145–51. http://dx.doi.org/10.1023/b:aten.0000030914.99682.3f.

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24

Savchenko, A., A. Nikolaev, and D. Evstigneev. "Operation of vibration source of an unbalance type with liquid-filled internal working chamber." Journal of Physics: Conference Series 2131, no. 2 (December 1, 2021): 022066. http://dx.doi.org/10.1088/1742-6596/2131/2/022066.

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Abstract Equipment for increasing water inflow to the well is proposed, which affects the aquifer by seismic vibrations. The method is based on accelerating the filtration process in soils, exposed to vibration. The equipment can work in conjunction with a submersible pump and has the ability to pump liquid through the working chamber of the generator. Generators can be combined into a group and driven by one electric motor to increase the efficiency of vibration treatment. This method is built into the existing technology of dewatering and pits drainage. The dynamics of the vibration source operation of an unbalance type with a liquid-filled inner chamber was studied in laboratory conditions, on a test. The vibration source was attached to the stand frame and was in a vertical position coaxially with the electric drive, thereby simulating its location in the well. The unbalance was unwound by an electric drive with a rotation frequency of 10 to 50 Hz in 5 Hz steps and seismic vibrations, generated by a vibration source, were recorded. Based on the experiments’ results, the amplitude-frequency characteristics of an unbalanced vibration source in the low-frequency range with a dry and liquid-filled inner chamber were obtained. In order to prevent the bearing assemblies from jamming, their heating was monitored with a thermal imager and temperature sensors.

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Chen, Yugang, Jingyu Zhai, and Qingkai Han. "Multilevel finite element modeling and coupling vibration analysis of the drum in blade–disk–drum assembly." Proceedings of the Institution of Mechanical Engineers, Part G: Journal of Aerospace Engineering 231, no. 6 (May 2, 2016): 998–1011. http://dx.doi.org/10.1177/0954410016646600.

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Blade–disk–drum (BDD) assemblies are commonly used in rotors of aeroengine. This paper investigates the vibration characteristics of the drum in the BDD assembly. In the analysis, multilevel modeling method based on ANSYS software is proposed. Free vibrations of single drum, disk-drum assembly, and the BDD assembly are calculated and carefully examined to discover the special modal shapes and coupling effects. Then according to the working environment, equivalent aerodynamic loads are imposed on blades and the drum respectively, to explore the vibration behaviors of the drum in the BDD assembly. Results reveal that, vibration of the drum, which may result in rub-impact or/and fatigue failure, can be induced by coupling vibration result from the aerodynamic loads on blades and drum, as well as the drum-dominant mode triggered by the aerodynamic loads on drum.

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26

Scattergood, Paul A., Milan Delor, Igor V. Sazanovich, Michael Towrie, and Julia A. Weinstein. "Ultrafast charge transfer dynamics in supramolecular Pt(ii) donor–bridge–acceptor assemblies: the effect of vibronic coupling." Faraday Discussions 185 (2015): 69–86. http://dx.doi.org/10.1039/c5fd00103j.

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Thanks to major advances in laser technologies, recent investigations of the ultrafast coupling of nuclear and electronic degrees of freedom (vibronic coupling) have revealed that such coupling plays a crucial role in a wide range of photoinduced reactions in condensed phase supramolecular systems. This paper investigates several new donor–bridge–acceptor charge-transfer molecular assemblies built on a trans-Pt(ii) acetylide core. We also investigate how targeted vibrational excitation with low-energy IR light post electronic excitation can perturb vibronic coupling and affect the efficiency of electron transfer (ET) in solution phase. We compare and contrast properties of a range of donor–bridge–acceptor Pt(ii) trans-acetylide assemblies, where IR excitation of bridge vibrations during UV-initiated charge separation in some cases alters the yields of light-induced product states. We show that branching to multiple product states from a transition state with appropriate energetics is the most rigid condition for the type of vibronic control we demonstrate in our study.

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27

Li, Chaofeng, Shihua Zhou, Shuhua Yang, Xiang Ren, and Bangchun Wen. "Dynamic Characteristics of Blade-Disk-Rotor System with Structural Mistuned Features." Open Mechanical Engineering Journal 8, no. 1 (April 18, 2014): 138–43. http://dx.doi.org/10.2174/1874155x20140501008.

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The finite element method is adopted to establish the dynamical models of blade, bladed disk and blades-diskshaft assemblies. Based on the analysis of mistuned structure and the dynamic characteristics of model in different levels, it gives the vibration mode distribution of different models. The research shows that the characteristics of the bladed disk and shaft have a huge difference, where some modes are caused by the strongly split and coupled vibration. The mistuned effects are likely to cause different coupled vibrations of blades between the blades-disk model and the blades-disk-shaft model. Meanwhile, it shows the frequency separation and concentration, and misses the system mode and the local vibration, which bring some difficulties for designing the blade-rotor system. In this paper, the results may provide a certain reference for blade-rotor system design and diagnosis.

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28

Janjić, Zoran. "TESTING TECHNOLOGIES OF HYDROAGGREGATE FOR THE PURPOSE OF ASSESSMENT OF VIBRATIONAL STATE IN EXPLOITATION." KNOWLEDGE - International Journal 54, no. 3 (September 30, 2022): 463–70. http://dx.doi.org/10.35120/kij5403463j.

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Vibrations of the basic assemblies of the hydrogen generator cause variable forces and loads that occurduring operation and depending on the operating mode. This paper presents some test results performed on a Kaplanvertical type turbine. Measurements were performed at 3 measuring points (N1, N2 and N3; Figure 1) using noncontactsensors, placed in pairs under 90 at each measuring point. Based on the measurements performed and theanalysis of the obtained results, the following can be concluded: hydraulic tests of the turbine were performed oninstruments that ensure high accuracy of these measurements. The tables show the absolute vibrations on thebearings of the hydro unit, as well as the vibrations of the turbine guide bearing

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Kolluru, K., and D. Axinte. "Novel ancillary device for minimising machining vibrations in thin wall assemblies." International Journal of Machine Tools and Manufacture 85 (October 2014): 79–86. http://dx.doi.org/10.1016/j.ijmachtools.2014.05.007.

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30

DIMITRIADIS, G., I. B. CARRINGTON, J. R. WRIGHT, and J. E. COOPER. "BLADE-TIP TIMING MEASUREMENT OF SYNCHRONOUS VIBRATIONS OF ROTATING BLADED ASSEMBLIES." Mechanical Systems and Signal Processing 16, no. 4 (July 2002): 599–622. http://dx.doi.org/10.1006/mssp.2002.1489.

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31

Sobhani, Emad. "Free vibrations of all assemblies related to coupled hyperboloidal–cylindrical shells." Thin-Walled Structures 184 (March 2023): 110469. http://dx.doi.org/10.1016/j.tws.2022.110469.

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32

Petrov, E. P., and D. J. Ewins. "Method for Analysis of Nonlinear Multiharmonic Vibrations of Mistuned Bladed Disks With Scatter of Contact Interface Characteristics." Journal of Turbomachinery 127, no. 1 (January 1, 2005): 128–36. http://dx.doi.org/10.1115/1.1812781.

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An efficient method for analysis of nonlinear vibrations of mistuned bladed disk assemblies has been developed. This development has facilitated the use of large-scale finite element models for realistic bladed disks, used hitherto in analysis of linear vibration, to be extended for the analysis of nonlinear multiharmonic vibration. The new method is based on a technique for the exact condensation of nonlinear finite element models of mistuned bladed disks. The model condensation allows the size of the nonlinear equations to be reduced to the number of degrees of freedom where nonlinear interaction forces are applied. The analysis of nonlinear forced response for simplified and realistic models of mistuned bladed disks has been performed. For a practical high-pressure bladed turbine disk, several types of nonlinear forced response have been considered, including mistuning by (i) scatter of underplatform dampers, (ii) shroud gap scatter, and (iii) blade frequency scatter in the presence of nonlinear shroud interactions.

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Szafran, Krzysztof Stanisław, and Marcin Michalczyk. "Research on Hovercraft – Fatigue Cracks in the Engine Frame." Fatigue of Aircraft Structures 2021, no. 13 (December 1, 2021): 106–15. http://dx.doi.org/10.2478/fas-2021-0010.

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Abstract Rescue patrol hovercrafts must meet the basic condition – high reliability of use in extreme conditions. The introduction to the work shows damage to the propulsion system and the fan tunnel structure resulting from a fatigue fracture of the attachment wound to the propulsion unit hull. In this paper, the author describes some ways of improving the engine frame structure. In the first phase of the exploitation crack testing of the hovercraft frame, the probable causes of damage were determined. The necessary output data for analysis of the load course were obtained from the operating documentation. The approximate number of variable load cycles acting on the frame truss rod was determined. Using the comparative testing methods, the service life of the frame was estimated. Probable resonance frequencies of the vibrating bars in the truss were determined. Vibration tests of the power transmission assemblies were carried out, which allowed to determine the amplitudes and frequencies of free vibrations. Finally, a modification of the frame shifting the resonant frequency range was proposed. In conclusions, changes to the design and a schedule of inspections were proposed. The newly designed engine frame should have an extended service life.

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Kumar, Kunal, Olaf Stefanczyk, Koji Nakabayashi, Yuuki Mineo, and Shin-ichi Ohkoshi. "Development of Nd (III)-Based Terahertz Absorbers Revealing Temperature Dependent Near-Infrared Luminescence." International Journal of Molecular Sciences 23, no. 11 (May 27, 2022): 6051. http://dx.doi.org/10.3390/ijms23116051.

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Molecular vibrations in the solid-state, detectable in the terahertz (THz) region, are the subject of research to further develop THz technologies. To observe such vibrations in terahertz time-domain spectroscopy (THz-TDS) and low-frequency (LF) Raman spectroscopy, two supramolecular assemblies with the formula [NdIII (phen)3 (NCX)3] 0.3EtOH (X = S, 1-S; Se, 1-Se) were designed and prepared. Both compounds show several THz-TDS and LF-Raman peaks in the sub-THz range, with the lowest frequencies of 0.65 and 0.59 THz for 1-S and 1-Se, and 0.75 and 0.61 THz for 1-S and 1-Se, respectively. The peak redshift was observed due to the substitution of SCN− by SeCN−. Additionally, temperature-dependent TDS-THz studies showed a thermal blueshift phenomenon, as the peak position shifted to 0.68 THz for 1-S and 0.62 THz for 1-Se at 10 K. Based on ab initio calculations, sub-THz vibrations were ascribed to the swaying of the three thiocyanate/selenocyanate. Moreover, both samples exhibited near-infrared (NIR) emission from Nd (III), and very good thermometric properties in the 300–150 K range, comparable to neodymium (III) oxide-based thermometers and higher than previously reported complexes. Moreover, the temperature dependence of fluorescence and THz spectroscopy analysis showed that the reduction in anharmonic thermal vibrations leads to a significant increase in the intensity and a reduction in the width of the emission and LF absorption peaks. These studies provide the basis for developing new routes to adjust the LF vibrational absorption.

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Wei, S. T., and C. Pierre. "Localization Phenomena in Mistuned Assemblies with Cyclic Symmetry Part I: Free Vibrations." Journal of Vibration and Acoustics 110, no. 4 (October 1, 1988): 429–38. http://dx.doi.org/10.1115/1.3269547.

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An investigation of the effects of small structural irregularities on the dynamics of nearly periodic structures with cyclic symmetry is presented. The system studied may be regarded as a simple model of a continuously shrouded blade assembly accounting for one structural mode per blade. A key aspect of the approach is the use of perturbation methods that lead to a physical insight into the effects of mistuning. The study shows that the sensitivity to mistuning depends primarily upon the ratio of mistuning strength to coupling strength. For a small mistuning to coupling ratio, the mistuned system behaves like a perturbation of the corresponding tuned system, in which case mistuning has a relatively small effect on both the free and forced responses. On the other hand, for a large mistuning to coupling ratio (i.e., weak coupling), the mistuned system behaves like a perturbation of the corresponding decoupled mistuned system, in which case small mistuning dramatically changes the dynamics of the system. This paper, Part I, investigates the effects of small mistuning on the free response of the system. Specifically, it is shown that strong mode localization and eigenvalue loci veering phenomena occur in the weakly coupled system when mistuning is introduced. The effects of mistuning on the forced response are studied in the companion paper, Part II (Wei and Pierre, 1987).

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36

Stakhova, Anzhelika, and Volodymyr Kvasnikov. "DEVELOPMENT OF A DEVICE FOR MEASURING AND ANALYZING VIBRATIONS." Informatyka, Automatyka, Pomiary w Gospodarce i Ochronie Środowiska 11, no. 2 (June 30, 2021): 48–51. http://dx.doi.org/10.35784/iapgos.2658.

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It is known that vibration is generated to one degree or another by all moving parts of machines. Vibration processes arising in the process of functioning of machines and equipment are highly informative, reflecting the technical condition of many parts and assemblies quite fully. Therefore, the use of vibration diagnostics systems makes it possible to determine a defect even at the stage of inception, thereby excluding emergency stops of machinery. An urgent task is to create a vibration analysis device, which consists of a sensor for measuring vibration, the principle of operation of which is based on the use of a direct piezoelectric effect. The output signal of the sensor will go to a personal computer or any other device with the Windows operating system, where a spectral analysis of the measured vibration signal is carried out using a Matlab-based diagnostic program.

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37

Jiang, Jinwei, Siu Chun Michael Ho, Nathanael J. Markle, Ning Wang, and Gangbing Song. "Design and control performance of a frictional tuned mass damper with bearing–shaft assemblies." Journal of Vibration and Control 25, no. 12 (March 1, 2019): 1812–22. http://dx.doi.org/10.1177/1077546319832429.

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This paper explores the feasibility of leveraging the damping generated by the friction between movable flange-mounted ball bearings and a stationary shaft. This bearing–shaft assembly is integrated with a tuned mass damper to form a frictional tuned mass damper (FTMD). The friction coefficient and the equivalent viscous damping ratio of the proposed FTMD were experimentally obtained based on different cases of glass, steel, and aluminum slide shafts. The proposed FTMD was modeled and simulated numerically to study its ability to suppress vibrations on a single degree of freedom structure. Furthermore, a parallel experimental validation of the FTMD was also executed to verify simulation results. Results from both experiments and simulations demonstrated that the proposed FTMD device was able to significantly improve the damping ratio of the primary structure from 0.35% to 5.326% during free vibration, and also to suppress around 90% of uncontrolled structural response at a tuned frequency. In particular, the frequency responses, among the tested shaft materials, suggested that the selected steel slide shaft practically provided a near-optimal damping coefficient, thus the proposed FTMD was able to considerably reduce structural resonant peak amplitudes over the tested excitation frequency domain.

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38

Migal, Vasiliy, Shchasiana Arhun, and Andrii Hnatov. "Vibration characteristics of tractor gearboxes." Vehicle and electronics. Innovative technologies, no. 21 (June 29, 2022): 87–96. http://dx.doi.org/10.30977/veit.2022.21.0.07.

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Problem. Improving the efficiency, quality, reliability and economy of tractor equipment is one of the most important tasks of modern society. This is due to the fact that in agriculture, tractors can perform up to 80% of various operations. The cost of production, product quality, compliance with the conditions of technological operations, etc. depend on the properties and reliability of tractors. The main factor limiting the effective use of tractors in agriculture is the problem of insufficient reliability of tractors, namely, the reliability of its individual components. One of the most important units is its gearbox. The existing methods for diagnosing tractor gearboxes are designed to detect damage, but they are not able to determine the quality of the gearbox at the design and manufacturing stage. Such an opportunity would greatly simplify the process of diagnosing tractor boxes. Goal. The purpose of the research is to assess the quality of design and manufacture of tractor boxes according to their vibration characteristics by identifying design and manufacturing defects, which will allow developing the ways to improve them. Methodology. Methods for detecting statistical data on the boundary values of structural vibrational parameters and their connection with the technical condition of tractors were used. Experimental research methods and mathematical methods for processing and modulating the results obtained were used as well as the methods of statistical calculation and comparison of vibration characteristics with permissible vibrations that do not affect the acceleration of the process of tractor parts wear. Results. Experimental studies of vibro-diagnostic characteristics of tractors were carried out. Studies were made to measure vibration diagnostic indicators; a spectral analysis of gearbox vibration was carried out. An assessment of the quality of manufacturing parts and assembly of tractor gearboxes was made. Such an assessment was carried out by analyzing the spread of the maximum and minimum vibration levels for a sample of gearboxes. Originality. An assessment was made of the possibilities of reducing vibration levels by observing the technology for the production of tractor boxes. This assessment was based on the analysis of minimum vibration levels of tractor boxes. Statistical processing of the results of experimental studies was carried out with the determination of the arithmetic mean, minimum and maximum vibrations, and the standard deviations of the vibration of gearboxes when the fourth gear of the third (transport) range is engaged. Practical value. Vibro-diagnostic characteristics of tractor boxes make it possible to evaluate the quality of design and manufacture by vibration levels. It was established that the vibration levels of boxes at the manufacturing stage reach 85-113 dB and exceed the permissible vibrations by 10-25 dB. The main sources of gearbox vibration are: defects in the quality of gears and bearing assemblies; their assembly, the use of low-quality bearings, large clearances of bearing fit in the housing, and the problem of gearbox assembly technology.

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39

ВОЙЦИЦЬКИЙ, АНАТОЛІЙ, та ІННА НЕЗДВЕЦЬКА. "ПІДВИЩЕННЯ ЯКОСТІ ВІБРАЦІЙНОЇ ДІАГНОСТИКИ ВУЗЛІВ ТА АГРЕГАТІВ АГРАРНОЇ ТЕХНІКИ". Herald of Khmelnytskyi National University. Technical sciences 331, № 1 (1 березня 2024): 61–64. http://dx.doi.org/10.31891/2307-5732-2024-331-9.

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Анотація:

It is known that friction and vibrations are the main factors affecting the condition of the equipment during its operation. Therefore, monitoring and diagnostics of vibration resistance of machines and mechanisms are of great importance for their effective operation. This article will present and describe methods of vibroacoustic diagnostics, which are simple and sensitive for detecting defects in various mechanisms and machines, in particular in the agricultural sector. One of the key elements used to diagnose and control the degree of wear of parts is a piezoelectric transducer. It is easy to use and highly accurate. Such converters are almost not affected by electric and magnetic fields, acoustic signals and other mechanical vibrations, except in certain cases. This article will consider the improvement of the piezoelectric transducer, which can be used to measure the vibration rate of oscillations of elements and assemblies of agricultural machines. The technical solution includes the use of a differential amplifier with buffer stages connected to a basic differential amplifier. This approach allows you to reduce the impact of out-of-band interference and increase measurement accuracy. The use of a common-mode perturbation voltage is also an important element in the improved piezoelectric transducer, helping to provide more accurate results. This article reveals important aspects of vibration diagnostics and offers a new technical solution to improve measurements. It will be useful for specialists in the field of mechanical engineering and agricultural industry, who are interested in effective control and support of machines and mechanisms during their work.

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40

Scherbakov, Alexander, Anatoly Chulenyov, Yury Deniskin, and Evgeny Grigoriev. "Application of correction factors in Rayleigh method in calculation of the fundamental frequency of vibration Cylindrical shell with rectangular cross section." E3S Web of Conferences 413 (2023): 04003. http://dx.doi.org/10.1051/e3sconf/202341304003.

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A number of gas turbine engine components, in particular, combustion chamber flame tube hoods, jet nozzles, afterburner chambers and some elements of the power body can be considered as thin-walled shells. Loads which excite vibrations of these assemblies are gas-dynamic forces of gas flow pulsation, loads transferred from supports from rotation of the unbalanced rotor, non-stationary flowing by an incoming air stream, dynamic loads, transferred to the engine through its attachment units to the aeroplane at landing and run, etc. The magnitude and nature of variation of these loads in time are not always describable, but their spectral composition is well studied. In this connection it is advisable to set and solve the problem of dynamic calculation of such assemblies as a problem of calculation of frequencies of their own vibrations in order to tune out dangerous resonance modes. Most of the GTE structures of thin-walled nodes are carried out as cylindrical shells. Therefore, below the shells of this configuration will be considered. In addition, it should be noted that the basic properties of the frequency spectrum of shells of rotation with curvilinear formations have a great qualitative similarity with the features of the frequency spectrum of cylindrical shells. We consider using correction factors in the Rayleigh method for calculating the fundamental frequency of cylindrical shell vibrations with rectangular cross section. The regularities of the behaviour of the correction coefficients are systematised. The relation between the type of correction coefficients and properties of the obtained approximated formula has been analyzed.

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41

STEININGER, Andreas, and Friedrich BLEICHER. "IN-PROCESS MONITORING AND ANALYSIS OF DYNAMIC DISTURBANCES IN BORING AND TREPANNING ASSOCIATION (BTA) DEEP DRILLING." Journal of Machine Engineering 18, no. 4 (November 30, 2018): 47–59. http://dx.doi.org/10.5604/01.3001.0012.7632.

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This paper presents an approach to monitor the dynamic disturbances of a BTA (boring and trepanning association) deep drilling system. High length to diameter ratios are the key characteristic of deep drilling processes compared to conventional drilling applications. Since length to diameter ratios of up to 150 for slender tool-boring-bar assemblies are common, the deep drilling process is sensitive to dynamic disturbances such as chatter and whirling vibrations. Whirling vibrations usually effect the shape of the hole and cause holes with several lobes. To gain a deeper understanding of the dynamic state of the process, a sensor application has been developed and was tested in practice. Experimental investigations on BTA deep drilling with continuous multi-sensory monitoring were conducted. The used setup allowed the determination of the frequencies of chatter and whirling vibrations during the cutting process by analysing the logged data using a continuous short-time Fourier transformation (STFT).

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42

Guo, C. Q., and M. P. Paı¨doussis. "Analysis of Hydroelastic Instabilities of Rectangular Parallel-Plate Assemblies." Journal of Pressure Vessel Technology 122, no. 4 (March 7, 2000): 502–8. http://dx.doi.org/10.1115/1.1286019.

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Flow-induced vibrations and hydroelastic instabilities of rectangular parallel-plate assemblies are studied theoretically. The extended Galerkin method is employed to solve the plate equation, while the Fourier transform technique is used to solve for the perturbation pressure from the potential flow equations. The mixed fluid-plate interaction boundary condition leads to a singular integral equation, which is solved numerically. The complex frequencies versus flow velocity and critical velocities are obtained for various plate aspect ratios and channel-height-to-plate-width ratios. The frequencies and critical velocities are found to decrease as the plate length increases and as the channel height decreases. Two types of instability are found, namely, single-mode divergence, mostly in the first mode, and coupled-mode flutter involving adjacent modes. Damping has a significant effect on post-divergence stability and coupled-mode flutter of the system. [S0094-9930(00)00403-0]

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43

Proskuryakov, K. N., A. V. Anikeev, E. Afshar, and D. A. Pisareva. "Use CFD Model of WWER-1200 Reactor for Prediction of Fuel Assemblies Vibrations." Global Nuclear Safety 12, no. 4 (December 2019): 62–70. http://dx.doi.org/10.26583/gns-2019-04-07.

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44

Ladevèze, P., L. Blanc, P. Rouch, and C. Blanzé. "A multiscale computational method for medium-frequency vibrations of assemblies of heterogeneous plates." Computers & Structures 81, no. 12 (May 2003): 1267–76. http://dx.doi.org/10.1016/s0045-7949(03)00041-5.

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45

Mogilevich, L. I., V. S. Popov, A. A. Popova, and A. V. Khristoforova. "Mathematical Simulation of Nonlinear Vibrations of a Channel Wall Interacting with a Vibrating die Via Viscous Liquid Layer." Herald of the Bauman Moscow State Technical University. Series Instrument Engineering, no. 2 (139) (June 2022): 26–41. http://dx.doi.org/10.18698/0236-3933-2022-2-26-41.

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The article considers the developed mathematical model and investigates the dynamics of the interaction of a channel wall supported by a nonlinear spring with a vibrating opposite wall through a viscous fluid layer filling the channel. A flat slotted channel formed by two absolutely rigid rectangular walls, parallel to each other was investigated. One of the channel dimensions in the plan was much larger than the other, which leads to the transition to a plane problem. The bottom channel wall rested on a spring with a cubic nonlinear characteristic, and the upper wall was a die oscillating according to a given law. The gap between the walls was assumed to be much smaller than the channel longitudinal dimension, and the amplitudes of wall vibrations were much less than the channel gap. The movement of the viscous fluid in the channel was considered to be creeping. The mathematical model of the channel under consideration consisted of an equation of the dynamics of a single-mass system with a spring having a cubic nonlinearity, as well as the Navier --- Stokes and continuity equations, supple-mented by the boundary conditions for fluid nonslip on the channel walls and its free outflow at the ends. The steady-state nonlinear vibrations of the bottom channel wall at the fundamental frequency were studied, and its hydroelastic response was determined. The proposed model can be used to study nonlinear vibrations of elastically fixed elements that are in contact with liquid and are parts of modern devices and assemblies

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46

Vallim, Matheus de B., José M. C. Dos Santos, and Argemiro L. A. Costa. "Motorcycle Analytical Modeling Including Tire–Wheel Nonuniformities for Ride Comfort Analysis." Tire Science and Technology 45, no. 2 (April 1, 2017): 101–20. http://dx.doi.org/10.2346/tire.17.450202.

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ABSTRACT The transmission of vibrations in motorcycles and their perception by the passengers are fundamental in comfort analysis. Tire nonuniformities can generate self-excitations at the rotational frequency of the wheel and contribute to the ride vibration environment. In this work a multi-body motorcycle model is built to evaluate the ride comfort with respect to tire nonuniformities. The aim is to obtain a multi–degrees-of-freedom dynamic model that includes both the contributions of the motorcycle and tire–wheel assembly structures. This representation allows the tire nonuniformities to predict the vertical force variations on the motorcycle and can be used through a root mean square acceleration evaluation for ride comfort analysis. The motorcycle model proposed is a 10-degrees-of-freedom system, where each tire–wheel is a 4-degrees-of-freedom model. The tire–wheel assemblies include two types of nonuniformities: lumped mass imbalance and radial run-out. Simulations of analytical models are compared with experimental tests.

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47

Gallego-Garrido, J., G. Dimitriadis, I. B. Carrington, and J. R. Wright. "A Class of Methods for the Analysis of Blade Tip Timing Data from Bladed Assemblies Undergoing Simultaneous Resonances—Part II: Experimental Validation." International Journal of Rotating Machinery 2007 (2007): 1–10. http://dx.doi.org/10.1155/2007/73624.

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Blade tip timing is a technique for the measurement of vibrations in rotating bladed assemblies. In Part I of this work a class of methods for the analysis of blade tip timing data from bladed assemblies undergoing two simultaneous synchronous resonances was developed. The approaches were demonstrated using data from a mathematical simulation of tip timing data. In Part II the methods are validated on an experimental test rig. First, the construction and characteristics of the rig will be discussed. Then, the performance of the analysis techniques when applied to data from the rig will be compared and analysed. It is shown that accurate frequency estimates are obtained by all the methods for both single and double resonances. Furthermore, the recovered frequencies are used to calculate the amplitudes of the blade tip responses. The presence of mistuning in the bladed assembly does not affect the performance of the new techniques.

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48

Kalinina, Elena, Doug Ammerman, Carissa Grey, Gregg Flores, Sylvia Saltzstein, and Nicholas Klymyshyn. "Full-Scale Assembly 30 cm Drop Test." MRS Advances 5, no. 5-6 (December 23, 2019): 265–74. http://dx.doi.org/10.1557/adv.2019.477.

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ABSTRACTCan Spent Nuclear Fuel withstand the shocks and vibrations experienced during normal conditions of transport? This question was the motivation for the multi-modal transportation test (MMTT) (Summer 2017), 1/3-scale cask 30 cm drop test (December 2018), and full-scale assembly 30 cm drop tests (June 2019). The full-scale ENSA ENUN 32P cask with 3 surrogate 17x17 PWR assemblies was used in the MMTT. The 1/3-scale cask was a mockup of this cask. The 30 cm drop tests provided the accelerations on the 1/3-scale dummy assemblies. These data were used to design full-scale assembly drop tests with the goal to quantify the strain fuel rods experience inside a cask when dropped from a height of 30 cm. The drop tests were first done with the dummy and then with the surrogate assembly. This paper presents the preliminary results of the tests.

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49

ALLISON, D. J., and R. S. SHARP. "On the low frequency in-plane forced vibrations of pneumatic tyre/wheel/suspension assemblies." Vehicle System Dynamics 27, sup001 (January 1997): 151–62. http://dx.doi.org/10.1080/00423119708969651.

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50

Drozdov, Yu N., A. A. Tutnov, An A. Tutnov, E. E. Alekseev, V. V. Makarov, and A. V. Afanas’ev. "Computational and experimental investigation of fretting corrosion and vibrations of VVÉR-1000 fuel assemblies." Atomic Energy 102, no. 6 (June 2007): 416–25. http://dx.doi.org/10.1007/s10512-007-0066-3.

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