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Preprint ARTICLE | doi:10.20944/preprints202108.0087.v1

Fabrication Methods of the Polygonal Masonry of Large Stone Blocks with Fitted Curved Surfaces in Megalithic Structures of Peru

Rostislav Lapshin

Subject: Engineering, Mechanical Engineering Keywords: stone block; polygonal masonry; clay model; pantograph; replica; chisel; hammer; megalith; Inca; Cusco; Ollantaytambo; Machu Picchu; Peru

Online: 3 August 2021 (14:55:33 CEST)

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Preprint ARTICLE | doi:10.20944/preprints201704.0124.v1

Design and Construction of NACA-4415 Airfoil with Various Shaped Surface Modifications

Rubiat Mustak

Subject: Engineering, Mechanical Engineering Keywords: airfoil; dimple; drag; lift

Online: 19 April 2017 (11:53:38 CEST)

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A fluid flowing over an object has a tendency to drag the object along it^’s flow direction. An object passing through a fluid which is stationary there is a tendency to slow the object down. For a stationary object in a fluid which is flowing there is a tendency to move the object in the fluid flowing direction .These tendencies of flowing fluid is known as drag. While moving through air airplanes also subjected to several drags. Airplanes subjected to pressure drag or form drag due to flow separation which is based on the pressure difference between the upstream and downstream surfaces of the object. Airplanes also subjected to Skin friction drag which results from the viscous shear of the fluid flowing over the object surface. In order to overcome these drags airplane wings cross section airfoils are designed very carefully. National Advisory Committee for Aeronautics, or NACA, developed and tested "families" of airfoils. Some of the most successful of these were the NACA four-digit and five-digit series. The necessary coordinates for designing NACA airfoil profiles are available in online. UIUC also provide coordinates for designing NACA airfoil profiles. But the present work describes the way of designing NACA four digit airfoils without taking any coordinates from available sources like google or any other search engines. Using C programming with the help of NACA provided equations a generalized source code is designed .Which will provide coordinates for designing any NACA four digit airfoil profiles .With the help of this obtained profile the wing model is also constructed using solid works. Using solid works model the real model was constructed using wood. The chord of regular surface airfoil is 21 cm and the span is also 21 cm. The airfoil profile taken for the model construction is NACA-4415 which is a four digit cambered airfoil.The present work also show some figures of an airfoil by applying certain surface modifications in form of dimples.

Preprint ARTICLE | doi:10.20944/preprints201803.0036.v1

Strength of PLA Components Fabricated with Fused Deposition Technology Using a Desktop 3D Printer as a Function of Geometrical Parameters of the Process

Vladimir Kuznetsov, Alexey Solonin, Oleg Urzhumtcev, Azamat Tavitov, Richard Schilling

Subject: Engineering, Mechanical Engineering Keywords: additive manufacturing; desktop 3D printing; Fused Deposition Modeling; Fused Filament Fabrication; Polylactic Acid; anisotropy; interlayer bonds; mechanical strength; digital fabrication

Online: 5 March 2018 (14:30:51 CET)

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Preprint ARTICLE | doi:10.20944/preprints202108.0087.v2

Fabrication Methods of the Polygonal Masonry of Large Tightly Fitted Stone Blocks with Curved Surface Interfaces in Megalithic Structures of Peru

Rostislav Lapshin

Subject: Engineering, Mechanical Engineering Keywords: stone block; polygonal masonry; clay model; pantograph; replica; chisel; hammer; megalith; Inca; Cusco; Ollantaytambo; Machu Picchu; Peru

Online: 14 October 2021 (15:03:47 CEST)

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Preprint ARTICLE | doi:10.20944/preprints202108.0087.v6

Fabrication Methods of the Polygonal Masonry of Large Tightly-fitted Stone Blocks with Curved Surface Interfaces in Megalithic Structures of Peru

Rostislav Lapshin

Subject: Engineering, Mechanical Engineering Keywords: stone block; polygonal masonry; clay model; pantograph; translator; parallelogram mechanism; replica; chisel; hammer; megalith; Inca; Cusco; Ollantaytambo; Machu Picchu; Sacsayhuaman; Peru

Online: 16 May 2022 (12:15:55 CEST)

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Preprint ARTICLE | doi:10.20944/preprints201701.0132.v1

A New Deep Learning Model for Fault Diagnosis with Good Anti-Noise and Domain Adaptation Ability on Raw Vibration Signal

Wei Zhang, Gaoliang Peng, Chuanhao Li, Yuanhang Chen, Zhujun Zhang

Subject: Engineering, Mechanical Engineering Keywords: intelligent fault diagnosis; convolutional neural networks; domain adaptation; anti-noise

Online: 30 January 2017 (12:15:03 CET)

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Preprint ARTICLE | doi:10.20944/preprints202203.0410.v3

Cross-sectional Analysis of Beams Subjected to Saint-Venant Torsion Using the Green’s Theorem and the Finite Difference Method

Valentin Fogang

Subject: Engineering, Mechanical Engineering Keywords: Theory of elasticity; Saint-Venant torsion; Green’s theorem; finite difference method; additional nodes; thin-walled sections; stress concentration at reentrant corners; multiply connected cross-section; warping displacement

Online: 1 June 2022 (11:01:06 CEST)

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This paper presents an approach to the elastic analysis of beams subjected to Saint-Venant torsion using Green’s theorem and the finite difference method (FDM). The Saint-Venant torsion of beams, also called free torsion or unrestrained torsion, is characterized by the absence of axial stresses due to torsion; only shear stresses are developed. A solution to this torsion problem consists of finding a stress function that satisfies the governing equation and the boundary conditions. The FDM is an approximate method for solving problems described with differential equations; it does not involve solving differential equations, equations are formulated with values at selected nodes of the structure. In this paper, the beam’s cross-section was discretized using a two-dimensional grid and additional nodes were introduced on the boundaries. The introduction of additional nodes allowed us to apply the governing equations at boundary nodes and satisfy the boundary conditions. Beams with solid sections as well as multiply connected cross-sections were analyzed using this model; shear stresses and localized stresses at reentrant corners, torsion constant, and warping displacements were determined. Furthermore, beams with thin-walled closed sections, single-cell or multiple-cell, were analyzed using the Prandtl stress function whereby a linear distribution of the shear stresses over the thickness was considered; closed-form solutions for shear stresses and torsion constant were derived. The results obtained in this study showed good agreement with the exact results for rectangular cross-sections, and the accuracy was increased through a grid refinement. For thin-walled closed sections, the shear stresses obtained at the centerline using the closed-form solutions were in agreement with the values using Bredt’s analysis but the maximal values in the cross-section, which did not necessarily occur at the position with the smallest thickness, were higher; in addition, the results using the closed-form solutions were in good agreement with those using FDM.

Preprint ARTICLE | doi:10.20944/preprints201607.0050.v1

Simulation of Boiling Process in a Nanochannel with 700000 Argon Particles by Molecular Dynamics

Amin Etminan, Davood Toghraie, Ahmad Sharifian, Zambri Harun

Subject: Engineering, Mechanical Engineering Keywords: Nanochannel; Molecular Dynamics Method; Nanoparticle, Argon; Boiling Process

Online: 18 July 2016 (10:37:40 CEST)

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Preprint ARTICLE | doi:10.20944/preprints201610.0071.v1

A Rapid Magnetofluidic Micromixer Using Diluted Ferrofluid

Majid Hejazian, Nam-Trung Nguyen

Subject: Engineering, Mechanical Engineering Keywords: magnetic; microfluidics; mixing; magnetoconvection; ferrofluid

Online: 18 October 2016 (08:00:38 CEST)

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Preprint ARTICLE | doi:10.20944/preprints201907.0217.v1

A Study on OpenFOAM's Overset Mesh Support Using Flow Past NACA 0018 Airfoil

Praveen Laws, Jaskaran Singh Saini, Ajit Kumar

Subject: Engineering, Mechanical Engineering Keywords: OpenFOAM; overset meshing; NACA 0018; high Reynolds number; CFD

Online: 18 July 2019 (11:29:28 CEST)

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Preprint ARTICLE | doi:10.20944/preprints201702.0062.v1

A Probabilistic Approach to Small Fatigue Crack Initiation and Sizing Using Acoustic Emission

Azadeh Keshtgar, Mohammad Modarres

Subject: Engineering, Mechanical Engineering Keywords: acoustic emission; crack initiation; small crack growth; structural integrity; bayesian estimation

Online: 16 February 2017 (09:43:59 CET)

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Preprint ARTICLE | doi:10.20944/preprints201704.0072.v1

Techno-Economic Analysis of Hydrokinetic Turbines

Anurag Kumar, R. P. Saini

Subject: Engineering, Mechanical Engineering Keywords: ultra-low head turbines; cost correlations; Darrieus; Savonius; small hydro energy

Online: 13 April 2017 (06:06:08 CEST)

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Preprint REVIEW | doi:10.20944/preprints201910.0078.v1

Small-Scale Rotor Aeroacoustics for Drone Propulsion: A Review of Noise Sources and Control Strategies

Paolo Candeloro, Tiziano Pagliaroli, Daniele Ragni, Silvia Di Francesco

Subject: Engineering, Mechanical Engineering Keywords: drones; aerodynamics; aeroacoustics; rotor noise; airframe noise; porous material

Online: 8 October 2019 (06:11:47 CEST)

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Preprint ARTICLE | doi:10.20944/preprints201608.0071.v1

Estimation of Distribution Algorithm for Energy-Efficient Scheduling in Turning Processes

Fang Wang, Yunqing Rao, Chaoyong Zhang, Qiuhua Tang, Liping Zhang

Subject: Engineering, Mechanical Engineering Keywords: energy-efficiency scheduling; flexible flow shop; estimation of distribution algorithm; turning processing

Online: 8 August 2016 (08:49:49 CEST)

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Preprint ARTICLE | doi:10.20944/preprints201701.0038.v1

Experimental Identification and Vibration Control of A Non-Collocated Piezoelectric Flexible Manipulator Using Optimal Multi-Poles Placement Control

Junqiang Lou, Jiangjiang Liao, Yiling Yang, Yanding Wei, Guoping Li

Subject: Engineering, Mechanical Engineering Keywords: experimental identification; multi-poles placement control; smart flexible manipulator; active vibration control; non-collocation

Online: 9 January 2017 (04:56:13 CET)

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Preprint ARTICLE | doi:10.20944/preprints201609.0060.v1

Imperfection Sensitivity of Nonlinear Vibration of Curved Single-Walled Carbon Nanotubes Based on Nonlocal Timoshenko Beam Theory

Iman Eshraghi, Seyed K. Jalali, Nicola Maria Pugno

Subject: Engineering, Mechanical Engineering Keywords: nonlinear vibration; imperfection; curved SWCNT; nonlocal theory; differential quadrature method (DQ)

Online: 18 September 2016 (10:14:46 CEST)

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Preprint ARTICLE | doi:10.20944/preprints201610.0066.v1

Modelling Crack Propagation in Aluminium-Alloys 2524-T3 and 7050-T7452 Subjected to Fatigue Loading at Low Temperature

J. J. Xiong, M. D. Liu

Subject: Engineering, Mechanical Engineering Keywords: fatigue; crack growth; low temperature; residual life; aluminum-alloy

Online: 17 October 2016 (11:27:13 CEST)

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Preprint ARTICLE | doi:10.20944/preprints201701.0091.v1

Shock Pulse Index and Its Application in the Fault Diagnosis of Rolling Element Bearings

Peng Sun, Yuhe Liao, Jing Lin

Subject: Engineering, Mechanical Engineering Keywords: fault diagnosis; shock pulse index; maximum correlated kurtosis deconvolution; teager energy operator; rolling element bearings

Online: 20 January 2017 (04:12:25 CET)

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Preprint ARTICLE | doi:10.20944/preprints201608.0023.v1

CFD Simulation and Microscopic Study of a Solitary Spherical Porous Adsorbent

John White

Subject: Engineering, Mechanical Engineering Keywords: Packed beds; Thermal heat; Porosity effect; Thermal contact resistance

Online: 3 August 2016 (08:29:06 CEST)

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Preprint ARTICLE | doi:10.20944/preprints201611.0086.v2

Self-Aligned Interdigitated Transducers for Acoustofluidics

Zhichao Ma, Adrian J. T. Teo, Say Hwa Tan, Ye Ai, Nam-Trung Nguyen

Subject: Engineering, Mechanical Engineering Keywords: surface acoustic wave; acoustofluidics; microfluidics; interdigitated transducers

Online: 22 November 2016 (09:41:32 CET)

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Preprint ARTICLE | doi:10.20944/preprints201701.0066.v1

Evaluation of Interface Defects for Inaccessible Reactor Shrink Fit Nozzle Weld by Ultrasonic Wave

Jaesun Lee, Younho Cho

Subject: Engineering, Mechanical Engineering Keywords: nuclear facility; ultrasonic interface wave; defect detection; nondestructive testing; finite element method; inaccessible nozzle

Online: 13 January 2017 (10:01:23 CET)

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Preprint ARTICLE | doi:10.20944/preprints201612.0138.v1

Vibration Damping Analysis of Lightweight Structures in Machine Tools

Francesco Aggogeri, Alberto Borboni, Angelo Merlo, Nicola Pellegrini, Raffaele Ricatto

Subject: Engineering, Mechanical Engineering Keywords: hybrid materials; machine tool structures; modal analysis; machine tool kinematics; aluminium metal foams; aluminium corrugated sandwiches; CFRP materials; FE simulations; damping

Online: 29 December 2016 (07:36:15 CET)

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Preprint ARTICLE | doi:10.20944/preprints201704.0071.v1

Anomaly Detection on Gas Turbine Fuel System Using a Sequential Symbolic Method

Fei Li, Hongzhi Wang, Guowen Zhou, Daren Yu, Jianzhong Li, Hong Gao

Subject: Engineering, Mechanical Engineering Keywords: gas turbine fuel system; anomaly detection; symbolic dynamic analysis; time series

Online: 13 April 2017 (05:36:51 CEST)

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Preprint EDITORIAL | doi:10.20944/preprints201609.0099.v1

Multiscale and Multimaterial Fabrication: The Challenge Ahead

Nam-Trung Nguyen

Subject: Engineering, Mechanical Engineering

Online: 27 September 2016 (10:21:10 CEST)

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Preprint TECHNICAL NOTE | doi:10.20944/preprints201611.0098.v1

Nonlinear Vibration Response of a Rectangular Tube with a Flexible End and Non-Rigid Acoustic Boundaries

Y. Y. Lee

Subject: Engineering, Mechanical Engineering Keywords: nonlinear plate vibration; structural acoustics; harmonic balance method

Online: 18 November 2016 (10:13:10 CET)

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Preprint ARTICLE | doi:10.20944/preprints201612.0139.v1

A Kinematic Model to Compensate the Structural Deformations in Machine Tools Using Fibre Bragg Grating (FBG) Sensors

Francesco Aggogeri, Alberto Borboni, Rodolfo Faglia, Angelo Merlo, Nicola Pellegrini

Subject: Engineering, Mechanical Engineering Keywords: kinematic model; fiber Bragg grating; deformations; machine tools calibration; predicted model; multiple regression analysis; finite element analysis

Online: 29 December 2016 (07:39:26 CET)

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Preprint ARTICLE | doi:10.20944/preprints201805.0164.v2

Toward a More Complete, Flexible, and Safer Speed Planning for Autonomous Driving via Convex Optimization

Yu Zhang, Huiyan Chen, Steven L. Waslander, Tian Yang, Sheng Zhang, Guangming Xiong, Kai Liu

Subject: Engineering, Mechanical Engineering Keywords: speed planning; convex optimisation; autonomous driving; friction circle; driving safety; dynamic obstacle avoidance; ride comfort; mobility

Online: 16 May 2018 (11:08:49 CEST)

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Preprint ARTICLE | doi:10.20944/preprints201612.0047.v1

The Influence of Tool Texture on Friction and Lubrication in Strip Reduction Testing

Mohd Hafis Sulaiman, Peter Christiansen, Niels Bay

Subject: Engineering, Mechanical Engineering Keywords: tool surface texture; lubricant entrapment; strip drawing test

Online: 8 December 2016 (10:09:36 CET)

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Preprint ARTICLE | doi:10.20944/preprints201706.0007.v1

Pipeline Leak Detection by Transient-Based Method Using MATLAB® Functions

Albert Carbó-Bech, Salvador A. De Las Heras, Alfredo Guardo

Subject: Engineering, Mechanical Engineering Keywords: pipeline modeling; leak detection; transient-based method; pipeline system

Online: 1 June 2017 (08:20:31 CEST)

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Preprint ARTICLE | doi:10.20944/preprints201703.0184.v1

Parametric Study of the Centrifugal Insurance Mechanism in MEMS Safety and Arming Device

Dakui Wang, Wenzhong Lou, Yue Feng, Fufu Wang

Subject: Engineering, Mechanical Engineering Keywords: MEMS S&A device; centrifugal insurance mechanism; nonlinear dynamic method; parametric study

Online: 24 March 2017 (10:04:55 CET)

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Preprint ARTICLE | doi:10.20944/preprints201708.0010.v1

Solar Radiation–The Estimation of the Optimum Tilt Angles for South-Facing Surfaces in Pristina

Xhevat Berisha, Arianit Zeqiri, Drilon Meha

Subject: Engineering, Mechanical Engineering Keywords: solar energy; gains; estimation; tilt angle; south-facing; surface; Pristina

Online: 3 August 2017 (10:51:13 CEST)

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Preprint ARTICLE | doi:10.20944/preprints201708.0002.v1

M2M Security Technology of CPS Based on Blockchains

Yin Shiyong, Jin song Bao, Zhang Yiming, Huang Xiaodi

Subject: Engineering, Mechanical Engineering Keywords: blockchain; M2M; CPS; cotton spinning production

Online: 2 August 2017 (12:40:05 CEST)

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Preprint ARTICLE | doi:10.20944/preprints201703.0044.v1

Effect of Constitutive Equations on Prediction Accuracy for Springback in Cold Stamping of TRIP1180

Ki-Young Seo, Jae-Hong Kim, Hyun-Seok Lee, Ji Hoon Kim, Byung-Min Kim

Subject: Engineering, Mechanical Engineering Keywords: advanced high strength steel; yield function; hardening model; springback; deformation mode

Online: 8 March 2017 (04:51:37 CET)

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Preprint ARTICLE | doi:10.20944/preprints201705.0116.v1

Big-Data-Based Thermal Runaway Prognosis of Battery Systems for Electric Vehicles

Jichao Hong, Zhenpo Wang, Peng Liu

Subject: Engineering, Mechanical Engineering Keywords: thermal runaway; big-data platform; battery systems; electric vehicles; National Service and Management Center for Electric Vehicles

Online: 16 May 2017 (03:18:57 CEST)

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Preprint ARTICLE | doi:10.20944/preprints201709.0145.v1

Independent Assessment and Benchmarking of no/low cost Finite Element Analysis Software for Linear Static Structural Analysis

Saien Rugdeo, Clinton Bemont, Jean-François Pitot de la Beaujardiere

Subject: Engineering, Mechanical Engineering Keywords: Open source; FEA; finite element analysis; linear static structural; Code Aster; Salome Meca; Mecway; SimScale; Z88, CAE

Online: 28 September 2017 (14:58:31 CEST)

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Preprint ARTICLE | doi:10.20944/preprints201703.0135.v1

High-Cycle Microscopic Corrosion Fatigue Behavior and Life Prediction of 25CrMo Steel Used in Railway Axle

Xi-Shu Wang, Yan-Ling Wang, Sheng-Chuan Wu, Hui-Hui Yang, Zhi-Hao Zhang

Subject: Engineering, Mechanical Engineering Keywords: corrosion fatigue; characteristic life prediction; 25CrMo steel; microscopic analysis; Weibull distribution

Online: 17 March 2017 (05:11:02 CET)

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Preprint ARTICLE | doi:10.20944/preprints201707.0007.v1

Axial fan blade vibration under inlet cross-flow

Till Heinemann, Stefan Becker

Subject: Engineering, Mechanical Engineering Keywords: axial fan; laser scanning vibrometry; wind tunnel; inlet cross-flow; blade vibration

Online: 5 July 2017 (04:22:10 CEST)

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Preprint ARTICLE | doi:10.20944/preprints202008.0123.v1

A Study of ZVS, ZCS and ZVZCS Techniques in Reducing the Energy Loss and Improving the Soft Switching Range

Ratil H Ashique, Zainal Salam

Subject: Engineering, Mechanical Engineering Keywords: ZVZCS; ZVS; ZCS; soft switching; soft switching range

Online: 5 August 2020 (10:26:55 CEST)

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Preprint ARTICLE | doi:10.20944/preprints201704.0013.v1

Onset of Primary and Secondary Instabilities of Viscoelastic Fluids Saturating a Porous Layer Heated from below by a Constant Flux

Abdoulaye Gueye, Mohamed Najib Ouarzazi, Silvia C. Hirata, Haikel Ben Hamed

Subject: Engineering, Mechanical Engineering Keywords: viscoelastic fluids; porous media; convection; instability

Online: 4 April 2017 (08:07:04 CEST)

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We analyze the thermal convection thresholds and linear characteristics of the primary and secondary instabilities for viscoelastic fluids saturating a porous horizontal layer heated from below by a constant flux. Galerkin method is used to solve the eigenvalue problem by taking into account the elasticity of the fluid, the ratio between the viscosity of the solvent and the total viscosity of the fluid and the lateral confinement of the medium. For the primary instability, we found out that depending on the rheological parameters, two types of convective structures may appear when the basic conductive solution loses its stability: stationary long wavelength instability as for Newtonian fluids and oscillatory convection. The effect of the lateral confinement of the porous medium by adiabatic walls is to stabilize the oblique and longitudinal rolls and therefore selects transverse rolls at the onset of convection. In the range of the rheological parameters where stationary long wave instability develops first, we use a parallel flow approximation to determine analytically the velocity and temperature fields associated to the monocellular convective flow. The linear stability analysis of the monocellular flow is performed, and the critical conditions above which the flow becomes unstable are determined. The combined influence of the viscoelastic parameters and the lateral confinement on the characteristics of the secondary instability is quantified. The major new findings concerning the secondary instabilities may be summarized as follows: (i) For concentrated viscoelastic fluids, computations showed that the most amplified mode of convection corresponds to oscillatory transverse rolls which appears via a Hopf bifurcation. This pattern selection is independent of both the fluid elasticity and the lateral confinement of the porous medium; (ii) For diluted viscoelastic fluids, the preferred mode of convection is found to be oscillatory transverse rolls for a very laterally confined medium. Otherwise stationary or oscillatory longitudinal rolls may develop depending on the fluid elasticity. Results also showed the destabilizing effect of the relaxation fluid elasticity and the stabilizing effect of the viscosity ratio for the onset of both primary and secondary instabilities.

Preprint ARTICLE | doi:10.20944/preprints201703.0185.v1

Design, Fabrication and Analysis of Threshold-Value Judging Mechanism in MEMS Safety and Arming Device

Dakui Wang, Wenzhong Lou, Yue Feng, Fufu Wang

Subject: Engineering, Mechanical Engineering Keywords: MEMS S&A device; threshold-value judging mechanism; fabrication process; tensile test; theoretical, simulationand experimentalanalysis; parametric design method

Online: 24 March 2017 (10:12:13 CET)

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Preprint REVIEW | doi:10.20944/preprints201703.0038.v1

LEM Characterization of Synthetic Jet Actuators Driven by Piezoelectric Element: A Review

Matteo Chiatto, Francesco Capuano, Gennaro Coppola, Luigi de Luca

Subject: Engineering, Mechanical Engineering Keywords: synthetic jets; Lumped Element Model (LEM); piezo-driven actuators; flow control

Online: 7 March 2017 (08:51:39 CET)

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Preprint ARTICLE | doi:10.20944/preprints201703.0096.v1

A System Identification Technique Using Bias Current Perturbation for the Determination of the Magnetic Axes of an Active Magnetic Bearing

Dewey Spangler Jr., Robert Prins, Mary Kasarda

Subject: Engineering, Mechanical Engineering Keywords: magnetic bearing reaction; output current set point; error vector; empirical transformation equation; system identification

Online: 15 March 2017 (07:57:38 CET)

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Preprint ARTICLE | doi:10.20944/preprints201705.0033.v1

Techno-Economic Investigation of Solar Powered Electric Auto-Rickshaw for Sustainable Transport System

K S Reddy, Aravindhan S, Tapas K Mallick

Subject: Engineering, Mechanical Engineering Keywords: electric vehicle; solar power; techno-economic analysis; carbon emission mitigation; India

Online: 4 May 2017 (06:22:04 CEST)

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Preprint ARTICLE | doi:10.20944/preprints201611.0086.v1

Self-Aligned Interdigitated Transducers for Acoustofluidics

Zhichao Ma, Adrian J. T. Teo, Say Hwa Tan, Ye Ai, Nam-Trung Nguyen

Subject: Engineering, Mechanical Engineering Keywords: surface acoustic wave; acoustofluidics; microfluidics; interdigitated transducers

Online: 17 November 2016 (10:28:21 CET)

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Working Paper ARTICLE

Particle Transmission through Respirators Fabricated with Fused Filament Fabrication and Powder Bed Fusion Additive Manufacturing

Lindsey B. Bezek, Jin Pan, Charbel Harb, Callie E. Zawaski, Bemnet Molla, Joseph R. Kubalak, Linsey C. Marr, Christopher B. Williams

Subject: Engineering, Mechanical Engineering Keywords: COVID-19; additive manufacturing; N95; respirator; particle transmission; filtration efficiency

Online: 7 June 2020 (10:33:30 CEST)

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The COVID-19 pandemic has disrupted the supply chain for personal protective equipment (PPE) for medical professionals, including N95-type respiratory protective masks. To address this shortage, many have looked to the agility and accessibility of additive manufacturing (AM) systems to provide a democratized, decentralized solution to producing respirators with equivalent protection for last-resort measures. However, there are concerns about the viability and safety in deploying this localized download, print, and wear strategy. Several polymer-based AM processes produce porous parts, and inherent process variation between printers and materials also threaten the integrity of tolerances and seals within the printed respirator assembly. The goal of this paper is to quantitatively measure particle transmission through printed respirators of different designs, materials, and AM processes, and assess the viability of printed respirators as N95 equivalents. Results from this study show that respirators printed using desktop/industrial-scale fused filament fabrication processes and industrial-scale powder bed fusion processes have insufficient filtration efficiency at the size of the SARS-CoV-2 virus, even while assuming a perfect seal between the respirator and the user’s face. Almost all printed respirators provided <60% filtration efficiency at the 100-300 nm particle range. Only one respirator, printed on an industrial-scale fused filament fabrication system provided >90% efficiency as-printed. Post-processing procedures including cleaning, sealing surfaces, and reinforcing the filter cap seal generally improved performance, but no respirator sustained the filtration efficiency of an N95 respirator, which filters 95% of SARS-CoV-2 virus particles. Instead, the printed respirators showed similar performance to various cloth masks. While continued optimization of printing process parameters and design tolerances could be implemented to directly print respirators that provide the requisite 95% filtration efficiency, AM processes are not sufficiently reliable for widespread distribution and local production of N95-type respiratory protection without commensurate quality assurance processes in place. Certain design/printer/material combinations may provide sufficient protection for specific users, but the respirators should not be trusted without quantitative filtration efficiency testing. It is currently not advised to expect printed respirators originating from distributed designs to replicate performance across different printers and materials.

Preprint ARTICLE | doi:10.20944/preprints201902.0132.v1

Stag Beetle Elytra: Localized Shape-Retaining, Puncture and Wear-Resistant

Lakshminath Kundanati, Roberto Guarino, Nicola M. Pugno

Subject: Engineering, Mechanical Engineering Keywords: beetle elytra; snap-through; puncture-resistant

Online: 14 February 2019 (10:57:06 CET)

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Preprint ARTICLE | doi:10.20944/preprints201704.0136.v1

Multi-response Optimization of Surface Roughness Roundness and MRR in Precision Turn-Boring of 15-5PH Stainless Steel Using Taguchi-Grey Approach

Shen-Jenn Hwang, Yi-Hung Tsai

Subject: Engineering, Mechanical Engineering Keywords: surface roughness; roundness; MRR; turn-boring; optimization; Taguchi-grey

Online: 21 April 2017 (09:46:56 CEST)

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Preprint ARTICLE | doi:10.20944/preprints201705.0101.v1

CFD Analysis on the Air-Side Thermal-Hydraulic Performance of Multi-Louvered Fin Heat Exchangers at Low Reynolds Numbers

Arslan Saleem, Man-Hoe Kim

Subject: Engineering, Mechanical Engineering Keywords: compact heat exchanger; louvered fins; heat transfer coefficient; friction factor

Online: 12 May 2017 (05:00:34 CEST)

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Preprint ARTICLE | doi:10.20944/preprints201704.0066.v1

Modeling and Dynamics of a MDOF Isolation System

Youshuo Song, Xiuting Sun

Subject: Engineering, Mechanical Engineering Keywords: MDOF isolation platform; geometrical nonlinearity; vibration suppression; adjustable stiffness property

Online: 12 April 2017 (04:29:06 CEST)

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Preprint ARTICLE | doi:10.20944/preprints201704.0177.v1

Theoretical and Experimental Studies of a Switched Inertance Hydraulic System in a Four-Port High-Speed Switching Valve Configuration

Min Pan, Andrew Plummer, Abdullah El Agha

Subject: Engineering, Mechanical Engineering Keywords: digital hydraulics; switched inertance hydraulic systems; four-port switching valves; efficient fluid power

Online: 27 April 2017 (03:01:46 CEST)

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Preprint ARTICLE | doi:10.20944/preprints201708.0011.v1

Embedded Conjugated Polymer Sensor Arrays for Load Transmission Measurement in Orthopaedic Implants

Carolina Micolini, F. Benjamin Holness, James A. Johnson, Aaron David Price

Subject: Engineering, Mechanical Engineering Keywords: intrinsically conductive polymers; piezoresistance; polyaniline; sensing array; orthopaedic joint implants; reverse total shoulder arthroplasty; conjugated polymers

Online: 3 August 2017 (12:40:16 CEST)

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Preprint ARTICLE | doi:10.20944/preprints201707.0092.v1

Improvement of Sensitivity and Detectability of the Three-Coil Wear Debris Detection Sensor Using LC Resonance Method and Modified Lock-in Amplifier

Ran Jia, Biao Ma, Changsong Zheng, Liyong Wang, Qiu Du, Kai Wang

Subject: Engineering, Mechanical Engineering Keywords: wear debris detection; resonance method; sensitivity; phase controlled variable-frequency exciting system (PCVFES); modified lock-in amplifier (MLIA)

Online: 31 July 2017 (12:20:27 CEST)

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Preprint ARTICLE | doi:10.20944/preprints201706.0024.v1

An Improved Collaborative Algorithm with Artificial Neural Network in Multidisciplinary Design Optimization of AUV

Xiaodong Xu, Hongkai Li

Subject: Engineering, Mechanical Engineering Keywords: collaborative optimization algorithm; artificial neural network (ANN); low noise; low resistance; maneuvering performance

Online: 5 June 2017 (05:27:31 CEST)

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Preprint ARTICLE | doi:10.20944/preprints201705.0053.v2

Vibration Control Design for a Plate Structure with Electrorheological ATVA Using Interval Type-2 Fuzzy System

Chih-Jer Lin, Chun-Ying Lee, Ying Liu

Subject: Engineering, Mechanical Engineering Keywords: Electro-Rheological fluid; Semi-active vibration control; tunable vibration absorber; type-1 fuzzy control; interval type-2 fuzzy control

Online: 23 May 2017 (15:58:35 CEST)

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Preprint ARTICLE | doi:10.20944/preprints201707.0072.v1

Three-Dimensional Modeling Interaction of Shock Wave with Fin at Mach 5

Amjad A. Pasha

Subject: Engineering, Mechanical Engineering Keywords: high speed flows; shock wave; turbulent boundary layer; shock-unsteadiness; separation bubble; turbulence modeling; single fin

Online: 26 July 2017 (07:48:07 CEST)

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Preprint ARTICLE | doi:10.20944/preprints202006.0149.v1

Aerodynamic Study of an Ahmed Body with the Help of CFD Simulation

Indrashis Saha, Tathagatha Mukherjee, Ankit Saha, Richa Pandey

Subject: Engineering, Mechanical Engineering Keywords: Ahmed Body; vehicle aerodynamics; drag force measurement; Simulation/Numerical investigation

Online: 12 June 2020 (12:20:55 CEST)

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Preprint ARTICLE | doi:10.20944/preprints201705.0042.v1

Experimental and Analytical Characterization of Drop Impact Behavior for a Mobile Haptic Actuator

Byungjoo Choi, Jiwoon Kwon, Yongho Jeon, Moon Gu Lee

Subject: Engineering, Mechanical Engineering Keywords: drop test; impact analysis; reliability; haptic actuator; linear resonant actuator (LRA)

Online: 4 May 2017 (11:39:49 CEST)

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Preprint ARTICLE | doi:10.20944/preprints201704.0104.v1

Multi-Optimization of Performance Parameters in Turn-Boring for Difficult-to-Cut Ti-6Al-4V

Shen-Jenn Hwang, Xin-Tang Li

Subject: Engineering, Mechanical Engineering Keywords: turn-boring; Ti-6Al-4V; surface roughness; roundness error; power consumption; grey relational analysis

Online: 18 April 2017 (03:27:01 CEST)

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Preprint ARTICLE | doi:10.20944/preprints201704.0127.v1

Multi-Objective Optimization of in Precision Turn-Boring Parameters for AA7050-T7451 with Multiple Performance Characteristics

Shen Jenn Hwang, Yi-Hung Tsai

Subject: Engineering, Mechanical Engineering Keywords: turn-boring; AA 7050-T7451; surface roughness; roundness error; power consumption; Taguchi; grey relational analysis.

Online: 19 April 2017 (16:37:38 CEST)

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Preprint ARTICLE | doi:10.20944/preprints201706.0099.v1

Failure assessment of steel/CFRP double strap joints

Hamid Reza Majidi, Seyed Mohammad Javad Razavi, Filippo Berto

Subject: Engineering, Mechanical Engineering Keywords: double strap joint; failure load prediction; finite element analysis; steel; stress-based failure criterion.

Online: 21 June 2017 (03:26:57 CEST)

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Preprint ARTICLE | doi:10.20944/preprints201706.0050.v1

Strain Wave Acquisition by a Fiber Optic Coherent Sensor for Impact Monitoring

Claudio Sbarufatti, Alessio Beligni, Andrea Gilioli, Maddalena Ferrario, Marco Mattarei, Mario Martinelli, Marco Giglio

Subject: Engineering, Mechanical Engineering Keywords: lamb wave; coherent detection; interferometric fiber optic sensors; impact force reconstruction; finite element model; modelling

Online: 12 June 2017 (06:12:41 CEST)

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Preprint ARTICLE | doi:10.20944/preprints201704.0157.v1

Computational Study of Flow over Cascade Arrangement of Bluff Bodies with Different Geometries

Anurag Kumar, Sachendra Sachendra, Manish Singhal

Subject: Engineering, Mechanical Engineering Keywords: bluff body; cascade, turbulence; ANSYS; and simulation; offshore energy platform

Online: 25 April 2017 (09:59:58 CEST)

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Preprint ARTICLE | doi:10.20944/preprints201809.0346.v1

Automatic Fault Detection for Selective Laser Melting Using Semi-Supervised Machine Learning

Ikenna A. Okaro, Sarini Jayasinghe, Chris Sutcliffe, Kate Black, Paolo Paoletti, Peter L. Green

Subject: Engineering, Mechanical Engineering Keywords: SLM, Process Control, Semi-supervised Machine Learning, Randomised Singular Value Decomposition

Online: 18 September 2018 (11:21:58 CEST)

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Preprint ARTICLE | doi:10.20944/preprints201705.0188.v1

Application of a Composite Model in the Analysis of Creep Deformation at Low and Intermediate Temperatures

Xinjun Yang, Xiang Ling

Subject: Engineering, Mechanical Engineering Keywords: Creep; Composite constitutive model; θ projection method; low and intermediate temperature

Online: 25 May 2017 (17:35:30 CEST)

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Preprint ARTICLE | doi:10.20944/preprints201705.0122.v1

Analysis of the Aerodynamic and Structural Performance of a Cooling Fan with Morphing Blade

Alessio Suman, Annalisa Fortini, Nicola Aldi, Michele Pinelli, Mattia Merlin

Subject: Engineering, Mechanical Engineering Keywords: morphing blade; adaptive geometry; computational fluid dynamics; fluid-structure coupling

Online: 16 May 2017 (13:06:29 CEST)

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Preprint ARTICLE | doi:10.20944/preprints201906.0064.v1

Desktop Fabrication of Strong Poly (Lactic Acid) Parts: FFF Process Parameters Tuning

Vladimir Kuznetsov, Azamat Tavitov, Oleg Urzhumtcev, Artem Korotkov, Alexey Solonin, Sergey Solodov

Subject: Engineering, Mechanical Engineering Keywords: Fused Filament Fabrication; Fused Deposition Modeling; mechanical strength; interlayer bonding; technology optimization

Online: 7 June 2019 (15:37:54 CEST)

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Preprint ARTICLE | doi:10.20944/preprints202108.0087.v5

Fabrication Methods of the Polygonal Masonry of Large Tightly Fitted Stone Blocks with Curved Surface Interfaces in Megalithic Structures of Peru

Rostislav Lapshin

Subject: Engineering, Mechanical Engineering Keywords: stone block; polygonal masonry; clay model; pantograph; translator; replica; chisel; hammer; megalith; Inca; Cusco; Ollantaytambo; Machu Picchu; Sacsayhuaman; Peru

Online: 8 March 2022 (10:58:47 CET)

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Preprint ARTICLE | doi:10.20944/preprints201902.0091.v1

A Routine Thermal Response Test (TRT) for Estimating Soil Thermal Properties in Connection with Geotechnical Analysis

Alessandro Franco

Subject: Engineering, Mechanical Engineering Keywords: Ground coupled Heat Exchangers; Thermal Response Test; Thermal conductivity; Thermal diffusivity; Geotechnical properties; Borehole heat exchangers

Online: 11 February 2019 (16:13:18 CET)

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Preprint ARTICLE | doi:10.20944/preprints201706.0049.v1

Design Optimization of Angular Extrusion for Severe Plastic Deformation of Tubular Specimens

Madaraka Fredrick Mwema, Kiptoo Matthew, Shagwira Harisson, Obiko Japheth

Subject: Engineering, Mechanical Engineering Keywords: ECAP; Tubular channel angular pressing (TCAP); finite element; severe plastic deformation; strains

Online: 12 June 2017 (06:10:57 CEST)

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Preprint ARTICLE | doi:10.20944/preprints201912.0237.v1

Development of Continuum Robot Arm and Gripper for Harvesting Cherry Tomatoes

Azamat Yeshmukhametov, Koichi Koganezawa, Zholdas Buribayev, Yedilkhan Amirgaliyev, Yoshio Yamamoto

Subject: Engineering, Mechanical Engineering Keywords: tomato harvesting; gripper; continuum robot; tomato detection; design; agricultural robot

Online: 18 December 2019 (04:34:30 CET)

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Preprint ARTICLE | doi:10.20944/preprints201806.0111.v1

A Five-Bar Planar Parallel Manipulator with Two End-Effectors

Jaime Gallardo-Alvarado, Ramon Rodriguez-Castro, Luciano Perez-Gonzalez, Carlos R. Aguilar-Najera, Alvaro Sanchez-Rodriguez

Subject: Engineering, Mechanical Engineering Keywords: parallel manipulator; multiple end-effectors; Klein form; screw theory; kinematics

Online: 7 June 2018 (10:54:07 CEST)

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Preprint ARTICLE | doi:10.20944/preprints202109.0483.v1

Design and Analysis of a Helium-Assisted Hybrid Drone for Flight Time Enhancement

Geronimo Macias, Kooktae Lee

Subject: Engineering, Mechanical Engineering Keywords: Hybrid Drone; Helium UAV; Drone Design; Flight Time Increase; UAV Stability and Performance Analysis

Online: 29 September 2021 (09:50:49 CEST)

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Preprint ARTICLE | doi:10.20944/preprints202109.0299.v1

Local Thermal Rates and Gradients in Laser Powder Bed Fusion Metal Additive Manufacturing Method: Computer Simulation

Hamed Hosseinzadeh

Subject: Engineering, Mechanical Engineering Keywords: Metal 3D printing; Additive manufacturing; Powder bed fusion; Thermal simulation; Thermal history

Online: 17 September 2021 (09:28:45 CEST)

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Preprint ARTICLE | doi:10.20944/preprints202007.0385.v1

Study of Rayleigh Taylor Instability with the Help of CFD Simulation

Indrashis Saha

Subject: Engineering, Mechanical Engineering Keywords: CFD Simulation; Transient state; Rayleigh Taylor Instability; Multiphase Flow

Online: 17 July 2020 (14:20:55 CEST)

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Preprint ARTICLE | doi:10.20944/preprints201802.0044.v1

Optimization of Pump Hydraulic Performance Based on the Response Surface Method

Shengli Xu, Shaowei Zhong, Haixin Zhao

Subject: Engineering, Mechanical Engineering Keywords: pump hydraulic performance; optimization design; response surface method; parameterization; meridional plane

Online: 5 February 2018 (16:05:10 CET)

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Preprint ARTICLE | doi:10.20944/preprints201807.0249.v1

Reinforcement Systems for Carbon Concrete Composites Based on Low-Cost Carbon Fibers

Robert Böhm, Mike Thieme, Daniel Wohlfahrt, Daniel Wolz, Benjamin Richter, Hubert Jäger

Subject: Engineering, Mechanical Engineering Keywords: carbon concrete composites; low-cost carbon fibers; pultrusion

Online: 13 July 2018 (17:51:12 CEST)

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Preprint ARTICLE | doi:10.20944/preprints201708.0083.v1

Surface Profiling and Core Evaluation of Aluminum Honeycomb Sandwich Aircraft Panels Using Multi-Frequency Eddy Current Testing

Tyler Reyno, P. Ross Underhill, Thomas W. Krause, Catharine Marsden, Diane Wowk

Subject: Engineering, Mechanical Engineering Keywords: eddy current; multi-frequency eddy current; surface profiling; surface damage; honeycomb paneling

Online: 25 August 2017 (04:13:05 CEST)

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Preprint ARTICLE | doi:10.20944/preprints201810.0608.v1

Investigation of Micro Gas Turbine Systems for High Speed Long Loiter Tactical Unmanned Air Systems

James Large, Apostolos Pesyridis

Subject: Engineering, Mechanical Engineering Keywords: Unmanned Air Vehicles; Micro Gas Turbine Performance; Low Pressure Compressor; Preliminary Design

Online: 25 October 2018 (13:09:17 CEST)

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Preprint ARTICLE | doi:10.20944/preprints201705.0182.v1

The Induced Stress Field in Cracked Composites by Heat Flow

Jacob Aboudi

Subject: Engineering, Mechanical Engineering Keywords: fiber-reinforced composites; porous materials; thermal stresses; repre-sentative cell method; high-fidelity generalized method of cells

Online: 25 May 2017 (07:57:40 CEST)

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Preprint ARTICLE | doi:10.20944/preprints201907.0143.v1

Tensile Testing of Epoxy-Based Thermoset System Prepared by Different Methods

Ankur Bajpai, Bernd Wetzel

Subject: Engineering, Mechanical Engineering Keywords: Epoxy; tensile strength; mechanical properties

Online: 10 July 2019 (10:14:48 CEST)

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Preprint ARTICLE | doi:10.20944/preprints201710.0182.v1

Effect of LCF Pre-Damage on Very High Cycle Fatigue Behavior of TC21 Titanium Alloy

Nie Baohua, Zhao Zihua, Ouyang Yongzhong, Chen Dongchu, Chen Hong, Sun Haibo, Liu Shu

Subject: Engineering, Mechanical Engineering Keywords: very high cycle fatigue; fatigue pre-damage; titanium alloy; LCF

Online: 30 October 2017 (10:22:24 CET)

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Preprint ARTICLE | doi:10.20944/preprints202308.1163.v1

The Influence of Reverse Yielding on the Plastic Conditioning of Interference Fits in the Power Transmission Engineering

Mario Schierz, Alexander Hasse

Subject: Engineering, Mechanical Engineering Keywords: Reverse Yielding, Plastic Conditioning, Plastically Joined Interference Fits, Elastic Stress Limits, Strain Hardening, Plastic Behavior of Materials, Residual Stresses, Joint Pressure

Online: 16 August 2023 (20:25:04 CEST)

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Preprint ARTICLE | doi:10.20944/preprints201801.0159.v2

Development of Piezoelectric Harvesters with Integrated Trimming Devices

Alberto Doria, Cristian Medè, Giulio Fanti, Daniele Desideri, Alvise Maschio, Federico Moro

Subject: Engineering, Mechanical Engineering Keywords: harvester; piezoelectric; dynamic vibration absorber; trimming

Online: 13 March 2018 (04:42:34 CET)

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Preprint ARTICLE | doi:10.20944/preprints201810.0242.v1

Simulation of a Hydraulic Load Sensing Proportional Valve

Sanjar Mirzaliev, Kungratbai Sharipov

Subject: Engineering, Mechanical Engineering Keywords: Amesim; proportional spool valve; PVG32; discharge coefficient

Online: 11 October 2018 (14:42:00 CEST)

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Nowadays energy saving is a topical issue due to increasing fuel costs and this aspect is amplified by more stringent emissions regulations that impact on vehicle development. A recent study conducted by the U.S. Department of Energy shows that about five percent of the U.S. energy consumption is transmitted by fluid power equipment. Nevertheless, this study also shows that the efficiency of fluid power averages 21 percent. This offers a huge opportunity to improve the current state-of-the-art of fluid power machines, in particular to improve the energy consumption of current applications. These facts dictate a continuous strive toward improvements and more efficient solutions: to accomplish this objective a strong reduction of hydraulic losses and better control strategies of the hydraulic systems are needed. In fluid power, there exist many techniques to reduce/recover energy losses of the conventional layouts, e.g. load sensing, electrohydraulic flow matching, independent metering, etc. One of the most efficient ways to analyze these different layouts and identify the best hydraulic solution is done through virtual simulations instead of prototyping, since the latter involves higher investment costs to deliver the product into the market. However, to build a fluid power machine virtual model, some problems arise relative to different aspects, for instance: loads on actuators (both linear and rotational) are not constant and pumps are driven by a real engine whose speed depends on required torque. Furthermore, it is important to achieve higher level of detail to simulate each component in the circuit: the greater detail, the better the machine behavior is portrayed, but it obviously entails heavy impact on simulation time and computational resources. Therefore, there is a need to create mathematical model of components and systems with sufficient level of detail to easily acquire all those phenomena necessary to correctly evaluate machine performance and make modifications to the fluid power component design. In this context, a hydraulic proportional valve PVG 32 by Danfoss is taken as an object of study, its performance is analyzed with suitable mathematical model and simulation is done to observe closeness of a model to the laboratory experiment.

Preprint ARTICLE | doi:10.20944/preprints202004.0350.v1

Cymatics Inspired Self-Cleaning Mechanism for Solar Panels

Edwin Babu, Sumith Yesudasan, Sibi Chacko

Subject: Engineering, Mechanical Engineering Keywords: solar panel; laminatel vibrations; self-cleaning; cymatics

Online: 19 April 2020 (13:51:32 CEST)

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Preprint ARTICLE | doi:10.20944/preprints201806.0149.v1

Motion Intention Estimation for Active Power-Assist Lower Limb Exoskeleton Robot (APAL)

Mantian Li, Jing Deng, Fusheng Zha, Shiyin Qiu, Xin Wang

Subject: Engineering, Mechanical Engineering Keywords: motion intention estimation; active power-assist; exoskeleton robot; inverse dynamics

Online: 11 June 2018 (10:08:47 CEST)

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Preprint ARTICLE | doi:10.20944/preprints201709.0059.v1

The Effect of Heat Transfer and Polymer Concentration on Non-Newtonian Fluid from Pore-Scale Simulation of Rock X-Ray micro-CT

Moussa Tembely, Ali M. AlSumaiti, Mohamed S. Jouini, Khurshed Rahimov

Subject: Engineering, Mechanical Engineering Keywords: pore-scale model; non-Newtonian fluid; Finite Volume Method; Digital Rock Physics

Online: 15 September 2017 (10:09:40 CEST)

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Preprint ARTICLE | doi:10.20944/preprints201905.0170.v2

Moving Surface Boundary Layer Control Analysis and the Influence of the Magnus Effect on an Aerofoil with a Leading-Edge Rotating Cylinder

Md. Abdus Salam, Bhuiyan Shameem Mahmood Ebna Hai, M. A. Taher Ali, Debanan Bhadra, Nafiz Ahmed Khan

Subject: Engineering, Mechanical Engineering Keywords: Moving surface boundary layer control; symmetric aerofoil; asymmetric aerofoil; velocity ratio; Magnus effect; lift coefficient; drag coefficient

Online: 17 May 2019 (13:06:27 CEST)

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Preprint ARTICLE | doi:10.20944/preprints201804.0002.v1

Numerical Study of the Air Flow over a NACA 0015 Wind Turbine Airfoil

Houari Ameur, Karima Boukhadia

Subject: Engineering, Mechanical Engineering Keywords: CFD; NACA airfoil; wind turbine; attack angle; wall pressure

Online: 1 April 2018 (11:46:52 CEST)

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Preprint ARTICLE | doi:10.20944/preprints201808.0130.v1

A New Structural Health Monitoring Strategy Based on PZT Sensors and Convolutional Neural Network

Mario A. de Oliveira, Andre V. Monteiro, Jozue Vieira Filho

Subject: Engineering, Mechanical Engineering Keywords: SHM; Electromechanical Impedance; Piezoelectricity; Intelligent Fault Diagnosis; Machine Learning; CNN; Deep Learning

Online: 6 August 2018 (21:51:53 CEST)

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Preprint ARTICLE | doi:10.20944/preprints202108.0087.v9

Fabrication Methods of the Polygonal Masonry of Large Tightly-fitted Stone Blocks with Curved Surface Interfaces in Megalithic Structures of Peru

Rostislav Lapshin

Subject: Engineering, Mechanical Engineering Keywords: stone block; polygonal masonry; clay model; pantograph; translator; parallelogram mechanism; replica; chisel; hammer; megalith; star fortress; Inca; Cusco; Ollantaytambo; Machu Picchu; Sacsayhuaman; Peru; polygonal bas-relief; polygonal Face Towers; Angkor; Cambodia; symmetrical statue; pharaoh statue; Ramses; Egypt

Online: 10 October 2023 (05:31:52 CEST)

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Preprint ARTICLE | doi:10.20944/preprints201808.0182.v1

Active Vibration Control of Launch Vehicle on Satellite Using Piezoelectric Stack Actuator

Mehran Makhtoumi

Subject: Engineering, Mechanical Engineering Keywords: Vibration Control, Piezoelectric, Fuzzy Logic Control, Launch Vehicle

Online: 9 August 2018 (09:06:34 CEST)

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Preprint ARTICLE | doi:10.20944/preprints201812.0058.v1

Estimating the Parameters of Dynamical Systems from Big Data Using Sequential Monte Carlo Samplers

Peter Green, Simon Maskell

Subject: Engineering, Mechanical Engineering Keywords: big data; parameter estimation; model updating; system identification; sequential Monte Carlo sampler

Online: 4 December 2018 (11:17:24 CET)

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Preprint ARTICLE | doi:10.20944/preprints202108.0087.v8

Fabrication Methods of the Polygonal Masonry of Large Tightly-fitted Stone Blocks with Curved Surface Interfaces in Megalithic Structures of Peru

Rostislav Lapshin

Subject: Engineering, Mechanical Engineering Keywords: stone block; polygonal masonry; clay model; pantograph; translator; parallelogram mechanism; replica; chisel; hammer; megalith; star fortress; Inca; Cusco; Ollantaytambo; Machu Picchu; Sacsayhuaman; Peru; polygonal bas-relief; polygonal Face Towers; Angkor; Cambodia; symmetrical statue; pharaoh statue; Ramses; Egypt

Online: 14 March 2023 (14:19:00 CET)

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Preprint ARTICLE | doi:10.20944/preprints201703.0075.v1

Lagrangian Solid Modeling

Matthew Marko

Subject: Engineering, Mechanical Engineering Keywords: Lagrangian, continuum mechanics, solid modeling, smoothing function, SPAM, SPH

Online: 14 March 2017 (08:36:58 CET)

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Preprint ARTICLE | doi:10.20944/preprints201708.0005.v1

A Compact 2-DOF Piezoelectric-Driven Platform Based on “Z-Shaped” Flexure Hinges

Jianping Li, Hui Liu, Hongwei Zhao

Subject: Engineering, Mechanical Engineering Keywords: piezoelectric; actuator; nano-positioning; flexure hinge; FEM

Online: 3 August 2017 (05:50:16 CEST)

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Preprint ARTICLE | doi:10.20944/preprints201710.0030.v1

The Analysis of Nonlinear Vibrations of Top Tensioned Cantilever Pipes Conveying Pressurized Steady Two-Phase Flow under Thermal Loading

Adeshina Adegoke, Ayo Oyediran

Subject: Engineering, Mechanical Engineering Keywords: Hamilton’s principle; Nonlinear vibration; Two-phase flow; Critical mixture velocity; Cantilever pipes; Perturbation method

Online: 6 October 2017 (08:31:13 CEST)

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Preprint REVIEW | doi:10.20944/preprints201806.0172.v1

A Systematic Overview of Soft Actuators for Robotics

Pinar Boyraz, Gundula Runge, Annika Raatz

Subject: Engineering, Mechanical Engineering Keywords: soft-actuators; scalability; actuator performance; DEAP; SMP; SMA; FEA

Online: 12 June 2018 (08:12:22 CEST)

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Preprint ARTICLE | doi:10.20944/preprints202108.0087.v7

Fabrication Methods of the Polygonal Masonry of Large Tightly-fitted Stone Blocks with Curved Surface Interfaces in Megalithic Structures of Peru

Rostislav Lapshin

Subject: Engineering, Mechanical Engineering Keywords: stone block; polygonal masonry; clay model; pantograph; translator; parallelogram mechanism; replica; chisel; hammer; megalith; star fortress; Inca; Cusco; Ollantaytambo; Machu Picchu; Sacsayhuaman; Peru; polygonal bas-relief; polygonal Face Towers; Angkor; Cambodia; symmetrical statue; pharaoh statue; Ramses; Egypt

Online: 5 December 2022 (14:48:24 CET)

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Preprint REVIEW | doi:10.20944/preprints201807.0438.v1

Sensing and Automation in Pruning of Tree Fruit Crops: A Review

Long He, James Schupp

Subject: Engineering, Mechanical Engineering Keywords: tree fruit; pruning; sensing; automation; robotics

Online: 24 July 2018 (05:32:11 CEST)

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