Georgie Crewdson, Marcello Lappa^*

FDMP-Fluid Dynamics & Materials Processing, Vol.18, No.3, pp. 497-510, 2022, DOI:10.32604/fdmp.2022.020248

Abstract The ability to control the distribution of particles in a fluid is generally regarded as a factor of great importance in a variety of fields (manufacturing processes, biomedical applications, materials engineering and various particle separation processes, to cite a few). The present study considers the hitherto not yet addressed situation in which solid spherical particles are dispersed in a non-isothermal fluid undergoing turbulent vibrationally-induced convection (chaotic thermovibrational flow in a square cavity due to vibrations perpendicular to the imposed temperature difference). Although the possibility to use laminar thermovibrational flows (in microgravity) and turbulent flows of various types (in normal gravity… More >

Guanni Qu^1,#, Tianai Yue^2,#,*, Xiaoyu Zhang³, Shibiao Wei³

FDMP-Fluid Dynamics & Materials Processing, Vol.18, No.3, pp. 591-608, 2022, DOI:10.32604/fdmp.2022.017776

Abstract The present study stems from the realization that the general problem relating to the analysis of wind-induced vibrations in suspension bridges still requires significant attention. Sidewalk railings, overhaul tracks, and deflectors are known to largely affect such dynamics. Here, the influence of a row of water-filled traffic barriers on the response of a sample suspension bridge is investigated numerically. It is shown that the existence of water barriers causes flow separation and non-negligible vortices with respect to the condition with no water barriers. The vortex shedding frequency at the far end is around 41.30 Hz, relatively close to the real… More >

Benedikt Plaumann^*

Sound & Vibration, Vol.56, No.1, pp. 1-19, 2022, DOI:10.32604/sv.2022.018634

Abstract This contribution shows an analysis of vibration measurement on large floor-mounted traction batteries of Battery Electric Vehicles (BEV). The focus lies on the requirements for a realistic replication of the mechanical environments in a testing laboratory. Especially the analysis on global bending transfer functions and local corner bending coherence indicate that neither a fully stiff fixation of the battery nor a completely independent movement on the four corners yields a realistic and conservative test scenario. The contribution will further show what implication these findings have on future vibration & shock testing equipment for large traction batteries. Additionally, it will cover… More >

Seyyed Mohammad Javad Golhosseini¹, Mohsen Aliabadi^2,*, Rostam Golmohammadi³, Maryam Farhadian⁴, Mehdi Akbari⁵, Morteza Hamidi Nahrani⁶, Mehdi Samavati⁷

Sound & Vibration, Vol.56, No.1, pp. 37-49, 2022, DOI:10.32604/sv.2022.014616

Abstract There is little information about drivers’ body balance responses to combined exposure of noise and vibration. To fill the gap, this study aims to investigate the combined effects of exposure to noise and whole-body vibration (WBV) on the body balance under simulated driving conditions. For this purpose, 30 male participants were exposed to noise level at 85 dB(A) and two vibration levels (0.87 and 1.3 m/s²) in five sessions. The design of the study was repeated-measures, and it attempted to assess the effects of 40 minutes of exposure to noise and/or WBV. Moreover, the participants’ fatigue was measured with the… More >

Yan Zhou^1,*, Kai Zhang², Feng Miao³, Pengfei Yang¹

CMES-Computer Modeling in Engineering & Sciences, Vol.130, No.3, pp. 1669-1682, 2022, DOI:10.32604/cmes.2022.018101

Abstract In this work, a monorail vehicle-bridge coupling (VBC) model capable of accurately considering curve alignment and superelevation is established based on curvilinear moving coordinate system, to study the VBC vibration of straddle monorail curved girder bridge and the relevant factors influencing VBC. While taking Chongqing Jiao Xin line as an example, the VBC program is compiled using Fortran, where the reliability of algorithm and program is verified by the results of Chongqing monorail test. Moreover, the effects of curve radius, vehicle speed, and track irregularity on the corresponding vehicle and bridge vibrations are compared and analyzed. It is observed that… More >

Kexin Zhang¹, Bin Lin^2,*, Jixin Chen¹, Xinlong Wu¹, Chao Lu³, Desheng Zheng¹, Lulu Tian⁴

Computer Systems Science and Engineering, Vol.42, No.1, pp. 351-360, 2022, DOI:10.32604/csse.2022.021132

Abstract Deep learning techniques have outstanding performance in feature extraction and model fitting. In the field of aero-engine fault diagnosis, the introduction of deep learning technology is of great significance. The aero-engine is the heart of the aircraft, and its stable operation is the primary guarantee of the aircraft. In order to ensure the normal operation of the aircraft, it is necessary to study and diagnose the faults of the aero-engine. Among the many engine failures, the one that occurs more frequently and is more hazardous is the wheeze, which often poses a great threat to flight safety. On the basis… More >

Carlos A. Felippa^*

CMES-Computer Modeling in Engineering & Sciences, Vol.129, No.3, pp. 1209-1241, 2021, DOI:10.32604/cmes.2021.016803

Abstract This paper considers Lagrangian finite elements for structural dynamics constructed with cubic displacement shape functions. The method of templates is used to investigate the construction of accurate mass-stiffness pairs. This method introduces free parameters that can be adjusted to customize elements according to accuracy and rank-sufficiency criteria. One- and two-dimensional Lagrangian cubic elements with only translational degrees of freedom (DOF) carry two additional nodes on each side, herein called side nodes or SN. Although usually placed at the third-points, the SN location may be adjusted within geometric limits. The adjustment effect is studied in detail using symbolic computations for a… More >

Ravindra Birajdar^1,*, Appasaheb Keste², Shravan Gawande²

Sound & Vibration, Vol.55, No.4, pp. 305-327, 2021, DOI:10.32604/sv.2021.017000

Abstract The objective of the study is to find the tolerance on vane pitch dimensions of a Vertical Turbine (VT) pump impeller. For this purpose, the study is divided into two parts viz. to find the critical hydraulic eccentricity of a VT pump impeller by way of numerical simulations and design of experiments to find the vane pitch tolerance using critical hydraulic eccentricity. The effect of impeller vane pitch deviations on hydraulic unbalance is examined for a vertical turbine pump using Design of Experiments (DOE). A suitable orthogonal matrix has been selected with vane pitch at different axial locations of an… More >

Olkan Çuvalcı¹, Faruk Ünker^2,*, Turgut Batuhan Baturalp³, Utku Gülbulak³, Atila Ertaş³

Sound & Vibration, Vol.55, No.4, pp. 281-294, 2021, DOI:10.32604/sv.2021.015705

Abstract In this paper, an experimental model of a horizontal cantilever beam with a rotating/oscillating attached to the shaker for harmonic excitation at the one end and a gyrostabilizer at the other end is built to verify the equations of the Lagrangian model. The primary focus of the study was to investigate the parameters of excitation amplitude, natural frequency, rotating mass (disk mass), and disk speed of gyro that would minimize the amplitude of the beam to identify these effects. Numerical and experimental results indicate that the angular momentum of the gyrostabilizer is the most effective parameter in the reduction of… More >

Junyu Chen¹, Yunwen Feng^1,*, Cheng Lu^1,2, Chengwei Fei²

CMES-Computer Modeling in Engineering & Sciences, Vol.129, No.2, pp. 1013-1027, 2021, DOI:10.32604/cmes.2021.016980

Abstract As the key component in aeroengine rotor systems, the health status of rolling bearings directly influences the reliability and safety of aeroengine rotor systems. In order to monitor rolling bearing conditions, a fusion fault diagnosis method, namely empirical mode decomposition (EMD)-Mahalanobis distance (E2MD) and improved wavelet threshold (IWT) (E2MD-IWT) for vibrational signals and acoustic emission (AE) signals is developed to improve the diagnostic accuracy of rolling bearings. The IWT method is proposed with a hard wavelet threshold and a soft wavelet threshold. Moreover, it is shown to be effective through numerical simulation. EMD is utilized to process the original AE… More >