Search results for "Numerical Analysis"
showing 10 items of 883 documents
Computational fluid dynamics and its application to transport processes
2007
Fluid transport behaviour is of great importance within the chemical process industry and in biotechnology. The complexity of this behaviour, reflected in the nature of the fundamental partial differential equations which describe it analytically, means that it has to be treated by numerical methods. In this paper the basic equations are given, and the approaches necessary to treat laminar and turbulent flows are carefully explained. As digital computers have increased in size, so has the comprehensiveness of the problems which can be treated, and the development of typical computer programs is described. Problems of accuracy and experimental validation are also surveyed, and it is shown th…
Sheet Thinning Prediction in Single Point Incremental Forming
2005
Incremental forming processes are characterized by a well known and particular feature: any deformation across the sheet plane determines sheet thinning, since the blank is fully clamped by means of a proper equipment. As a consequence, the availability of effective and reliable CAE tools capable to supply an accurate prediction of sheet thinning as a function of process parameters, represents a strong requirement for a wider practical application of incremental forming. The already available theoretical models (i.e. the sine law) do not provide, on the other hand, satisfactory results. Therefore in the paper a couple of numerical analysis strategies was applied to simulate simple increment…
Application of a decision making method to improve an industrial hot extrusion forging process
1999
Abstract Success of a bulk forming process is significantly affected by several operative parameters, such as dies and workpiece temperature, friction factor, preformed dimensions and its initial positioning. In the paper the hot extrusion forging of an half shaft of a two stroke motorcycle engine has been investigated. The combined effect of the most influent operative parameters has been determined by means of a consistent factorial plan. A sensitivity analysis was performed using an advanced numerical finite element code as a powerful CAE tool able to assist the analyst in the design of the process. The geometry of the part has allowed a combined 2D-3D numerical analysis; in fact, the in…
A Simple Model for the Axial Thrust in V-Belt Drives
1996
Simple formulas can relate axial thrust and torque of rubber V-belt drives, taking into consideration the radial penetration of the belt.
Shape Distortion and Thickness Distribution during SPIF Processes: Expermental and Numerical Analysis
2011
Single Point Incremental Forming (SPIF) is a quite new sheet forming process which offers the possibility to deform complex parts without dedicated dies using only a single point tool and a standard 3-axis CNC machine. The process mechanics enables strains much higher than traditional sheet forming processes, but particular attention must be given to the final part geometrical accuracy. In this paper the capabilities of a dedicated explicit numerical model are quantitatively analyzed on pyramid-shaped parts. In particular a comparison between experimental and numerical results is reported. Three different shapes at the varying of the stamping angle were considered and the final shape was ac…
Applicability of over-coring technique to loaded RC columns
2014
Stress determination is a very important step in the assessment of the safety of existing reinforced concrete structures. In rock mechanic this goal is achieved with the over-coring technique. The main idea behind such a technique is to isolate a material sample from the stress field in the surrounding mass and monitor its re-equilibrium deformation response. If the materials remains elastic, and elastic properties are known, stresses may be obtained from the corresponding measured strains. The goal of this paper is to evaluate if the over-coring technique is applicable to reinforced concrete members. The results of an experimental investigation on the behaviour of compressed concrete colum…
Stability analysis of clay brick masonry columns: numerical aspects and modelling strategies
2014
Stability analysis of masonry piers and columns is one of the most frequently treated subjects in the field of structural engineering. This attention is probably due to the challenge to solving the problem including different effects, which play an important role in evaluating the response of eccentrically-loaded columns. In this connection, accurate stability analysis of masonry piers and columns has to take into account the non-linear stress–strain law of masonry in compression, the limited tensile strength, the induced slenderness due to crack formation and geometrical non-linearity. Different theoretical models and numerical approaches were developed in the past to analyze the combined …
2-D approach to the analysis of semianechoic chambers using a hybrid technique
2003
Semianechoic chambers are the most widely used emplacements for electromagnetic compatibility (EMC) tests. In this work a new and efficient technique for the analysis of 2-D simplified model of a chamber with arbitrary absorber is introduced and validated Some advanced results are presented, and a 2-D figure of merit for studying the overall behaviour of the chamber is proposed.
Smooth and non-smooth traveling wave solutions of some generalized Camassa–Holm equations
2014
In this paper we employ two recent analytical approaches to investigate the possible classes of traveling wave solutions of some members of a recently-derived integrable family of generalized Camassa-Holm (GCH) equations. A recent, novel application of phase-plane analysis is employed to analyze the singular traveling wave equations of three of the GCH NLPDEs, i.e. the possible non-smooth peakon, cuspon and compacton solutions. Two of the GCH equations do not support singular traveling waves. The third equation supports four-segmented, non-smooth $M$-wave solutions, while the fourth supports both solitary (peakon) and periodic (cuspon) cusp waves in different parameter regimes. Moreover, sm…
Regular and singular pulse and front solutions and possible isochronous behavior in the short-pulse equation: Phase-plane, multi-infinite series and …
2014
In this paper we employ three recent analytical approaches to investigate the possible classes of traveling wave solutions of some members of a family of so-called short-pulse equations (SPE). A recent, novel application of phase-plane analysis is first employed to show the existence of breaking kink wave solutions in certain parameter regimes. Secondly, smooth traveling waves are derived using a recent technique to derive convergent multi-infinite series solutions for the homoclinic (heteroclinic) orbits of the traveling-wave equations for the SPE equation, as well as for its generalized version with arbitrary coefficients. These correspond to pulse (kink or shock) solutions respectively o…