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FEA-Analysis of Shaft and Supports Deformations for Huge Precise Lathe. Statics and Resonances

Abstract

Load bearing system simulation is provided for a huge lathe to be renovated. Static and modal analyses are done by FEM. Focus was centerline rising, needed for larger rotor shaft machining. Forces between shaft and three supports were applied. Shaft static stiffness is lowered at 1.15 times only for 600 mm centerline rising. Supports have lost its rigidity at 1.42 times. Concrete pouring into bed cavities is recommended for supports flexibility limitation such as tailstock reinforcement. Robustness of bottom resonances is revealed both for rotor shaft (14.5–18.2 Hz) and supports (42.7–55.4 Hz). Centerline rising is allowed on 300 mm at least. It gives possibility to machine extremely large (up to ø2750 mm) shafts.

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Development of Numerical Model and Comparison with the Analytical Model for Predicting the Wire Effects in Wire Electric Discharge Grinding

Abstract

This paper discusses the development of a numerical model and its comparison with the analytical model to predict the wire deflection in WEDG. The movement of wire between upper and lower guides creates vibration during the machining process which can create micro deflection of the wire. The Finite Element Analysis model [FEA] for the wire deflection is analyzed and compared with the analytical model. The deflection of the wire due to the input current may affect the machining of micro parts, which will be used for further research in micro machining and also will help us to choose the parameters such as current, spark gap, wire feed, and the speed of the workpiece during micro machining with WEDG. The FEA results for various forces were compared with the analytical results and found that the developed numerical model results are in good agreement.

Open access
Assessment of water-limited winter wheat yield potential at spatially contrasting sites in Ireland using a simple growth and development model

Agricultural Science 116 1 7 Schulte, R.P.O., Fealy, R., Creamer, R.E., Towers, W., Harty, T. and Jones, R.J.A. 2012. A review of the role of excess soil moisture conditions in constraining farm practices under Atlantic conditions. Soil Use and Management 28 : 580–589. 10.1111/j.1475-2743.2012.00437.x Schulte R.P.O. Fealy R. Creamer R.E. Towers W. Harty T. Jones R.J.A. 2012 A review of the role of excess soil moisture conditions in constraining farm practices under Atlantic conditions Soil Use and Management 28 580 589 Shalloo, L., Dillon, P

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Application of Anisotropic Thin Plate Theory for Development of Displacements for Silicon <111> Crystals Plates in Cylindrical Systems

Abstract

Silicon <111> crystal is one of the crystal orientations, which shows potential for application in micro device developments of pressure diaphragms for measurement purposes. To date, no theoretical basis has been examined to develop the deflections for computational analysis purposes [1]. This paper presents the development of the diaphragm deflections for Silicon <111> Crystal in Cylindrical coordinates system. The Silicon <111> crystal possesses transverse isotropic properties. Thus, an anisotropic thin plate theory is used here to develop the plate deflection. A numerical example is given to compare the theoretical results with Finite Element Analysis (FEA) results.

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Structural Analysis of Kufasat Using Ansys Program

Abstract

The current work focuses on vibration and modal analysis of KufaSat structure using ANSYS 16 program. Three types of Aluminum alloys (5052-H32, 6061-T6 and 7075-T6) were selected for investigation of the structure under design loads. Finite element analysis (FEA) in design static load of 51 g was performed. The natural frequencies for five modes were estimated using modal analysis. In order to ensure that KufaSat could withstand with various conditions during launch, the Margin of safety was calculated. The results of deformation and Von Mises stress for linear buckling analysis were also performed. The comparison of data was done to select the optimum material for KufaSat structures.

Open access
Buckling of Beams and Columns under Combined Axial and Horizontal Loading with Various Axial Loading Application Locations

Abstract

In this paper the buckling behaviour of an I-beam under combined axial and horizontal side loading is examined. It is to shown that the actual application location of the axial loading governs the buck- ling behaviour of the long I-beam. Theoretical formulation is developed to determine the critical buckling load for such combined loading configura- tion from the elastic static theory. Both, the beam deflection theoretical model and the critical load capacity are derived for this combined loading condition. The Finite Element Analysis (FEA) is utilized to apply the axial load on the beam at various configuration locations and it is shown that this application location determines the buckling behaviour and the critical load of the buckling of the I-beam. Numerical example is given.

Open access
PARAMETRIC ANALYSIS FOR THE DESIGN OF A 4 POLE RADIAL PERMANENT MAGNET GENERATOR FOR SMALL WIND TURBINES

Abstract

A review of the literature gives several guidelines for the design of a Permanent Magnet Synchronous Generator (PMSG) for Small Wind Turbines (SWT) applications. This paper presents Finite Element Analysis (FEA) of a Surface Mounted PMSG. Several optimization tests are run in order to yield the lowest Total Harmonic Distortion (THD) and cogging torque with the highest induced voltage. The results of the optimization tests are then utilized to design an initial “optimized” circumferential Internal PMSG. This optimized design is then compared to a non-optimized design, as well as the results of the Surface Mounted PMSG.

Open access
Load-carrying capacity of the GFRP and CFRP composite beams subjected to three-point bending test – numerical investigations

were estimated for composite beams of GFRP and CFRP material type. Beam response to three-point flexure test was investigated in full load range. Equilibrium paths available for FEA SOLID185 and SHELL181 element types were compared. This allowed one to verify the implemented element types, modelling procedures and to confirm the applied BCs. Numerical calculations included an attempt to estimate the potential damage of the beam subjected to three-point bending test. The strength analysis of the GFRP and CFRP beams was conducted either at each single layer

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Microstructural Damage Characteristic of a Layer-to-Layer Three-Dimensional Angle-Interlock Woven Composite under Quasi-Static Tensile loading

Abstract

Three-dimensional angle-interlock woven composites (3DAWCs) are widely used for their excellent mechanical properties. The most significant feature is the existence of the undulated warp yarns along the thickness direction, which makes it interesting to study the mechanical properties in the warp direction. The quasi-static tensile behavior of a layer-to-layer 3DAWC along the undulated warp direction was studied by experimental and finite element analysis (FEA) methods. Based on the experimental results, the typical failure mode involving fibers, resin, and their interfaces was found. According to the FEA results, the stress concentration effect, key structural regions, and microstructural (yarn and resin) damage mechanism were obtained, which provided effective guidance for structural optimization design of the 3DAWC with stronger tensile resistance performance. In addition, the three-step progressive failure process of the 3DAWC under quasi-static tensile load was also described at the “yarn– resin” microstructural level.

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Finite Element Analysis Of Influence Of Flank Wear Evolution On Forces In Orthogonal Cutting Of 42CrMo4 Steel

Abstract

This paper presents analysis of flank wear influence on forces in orthogonal turning of 42CrMo4 steel and evaluates capacity of finite element model to provide such force values. Data about magnitude of feed and cutting force were obtained from measurements with force tensiometer in experimental test as well as from finite element analysis of chip formation process in ABAQUS/Explicit software. For studies an insert with complex rake face was selected and flank wear was simulated by grinding operation on its flank face. The aim of grinding inset surface was to obtain even flat wear along cutting edge, which after the measurement could be modeled with CAD program and applied in FE analysis for selected range of wear width. By comparing both sets of force values as function of flank wear in given cutting conditions FEA model was validated and it was established that it can be applied to analyze other physical aspects of machining. Force analysis found that progression of wear causes increase in cutting force magnitude and steep boost to feed force magnitude. Analysis of Fc/Ff force ratio revealed that flank wear has significant impact on resultant force in orthogonal cutting and magnitude of this force components in cutting and feed direction. Surge in force values can result in transfer of substantial loads to machine-tool interface.

Open access