FINITE ELEMENT ANALYSIS

Finite element analysis (FEA) is a numerical method for solving problems of engineering and mathematical physics while governing differential equations useful for problems with complicated geometries, loadings, and material properties analytical and critical tool, when it comes to product development for structural analysis or stress analysis. FEA Analysis is a cost-effective simulation tool for product designs better efficiency and reduces failure in manufacturing investment. The method is now applied to problems involving a wide range of phenomena, including vibrations, heat conduction, fluid mechanics and electrostatics. Few numerical methods which are commonly used to solve solid and fluid mechanics problems are Finite Difference Method, Finite Volume Method, Finite Element Method, Boundary Element Method, Meshless Method.

Finite element method (FEM) is a computational technique used to obtain approximate solutions of boundary value problems in engineering. Boundary value problems are also called field problems. The field is the domain of interest and most often represents a physical structure. The field variables are the dependent variables of interest governed by the differential equation. The boundary conditions are the specified values of the field variables (or related variables such as derivatives) on the boundaries of the field. The main advantages are Irregular Boundaries General Loads, Different Materials, Boundary Conditions, Variable Element Size, Easy Modification Dynamics, Nonlinear Problems (Geometric or Material).

BACKGROUND OF FINITE ELEMENT ANALYSIS

The finite element analysis can be traced back to the work by Alexander Hrennikoff (1941) and Richard Courant (1942). Hrenikoff introduced the framework method, in which a plane elastic medium was represented as collections of bars and beams. These pioneers share one essential characteristic: mesh discretization of a continuous domain into a set of discrete sub-domains, usually called elements.

• In 1950s, solution of large number of simultaneous equations became possible because of the digital computer.

• In 1960, Ray W. Clough first published a paper using term “Finite Element Method”. • In 1965, First conference on “finite elements” was held.

• In 1967, the first book on the “Finite Element Method” was published by Zienkiewicz and Chung.

• In the late 1960s and early 1970s, the FEM was applied to a wide variety of engineering problems.

• In the 1970s, most commercial FEM software packages (ABAQUS, NASTRAN, ANSYS, etc.) originated. Interactive FE programs on supercomputer lead to rapid growth of CAD systems.

• In the 1980s, algorithm on electromagnetic applications, fluid flow and thermal analysis were developed with the use of FE program.

• Engineers can evaluate ways to control the vibrations and extend the use of flexible, deployable structures in space using FE and other methods in the 1990s. Trends to solve fully coupled solution of fluid flows with structural interactions, bio-mechanics related problems with a higher level of accuracy were observed in this decade.

With the development of finite element method, together with tremendous increases in computing power and convenience, today it is possible to understand structural behavior with levels of accuracy. This was in fact the beyond of imagination before the computer age.


A GENERAL PROCEDURE FOR FINITE ELEMENT ANALYSIS

PREPROCESSING

⦁ Define the geometric domain of the problem.
⦁ Define the element type(s) to be used.
⦁ Define the material properties of the elements.
⦁ Define the geometric properties of the elements (length, area, and the like).
⦁ Define the element connectivities (mesh the model).
⦁ Define the physical constraints (boundary conditions). Define the loadings.

SOLUTION

⦁ computes the unknown values of the primary field variable(s)
⦁ computed values are then used by back substitution to compute additional, derived variables, such as reaction forces, element stresses, and heat flow.

POSTPROCESSING

⦁ Postprocessor software contains sophisticated routines used for sorting, printing, and plotting selected results from a finite element solution.

APPLICATIONS

 

1.Mechanical, Aerospace, Civil,Automotive Engineering Structural.
2.Stress Analysis
2.1. Static/Dynamic
2.2. Linear/Nonlinear.
3. Fluid Flow.
4. Heat Transfer.
5.Electromagnetic Fields.
6 Soil Mechanics
7. Acoustics
8. Biomechanics.

Finite Element Analysis Engineering Services

Linear Static Stress Analysis

Factor of Safety Calculation
Part & Assembly Stress Analysis
Deflection Calculations
Correlation to Measurements of Deflections and Strains
Contact Stress Computation
Super-position of Thermal Stresses
Stiffness Calculations to achieve stated Targets

Frequency & Buckling Analysis

⦁ Computation of Frequencies & Mode Shapes
⦁ Modal Assurance Criteria (MAC)
⦁ Correlation to Measured data
⦁ Buckling Calculations for axially loaded members
⦁ Critical Speed Calculations
⦁ Campbell Diagram for Rotor-dynamics
⦁ Point Mobility Analysis.

Dynamic Analysis.

⦁ Frequency Response Analysis
⦁ Seismic Analysis Response Calculations
⦁ Harmonic Analysis
⦁ Random Vibration Calculations
⦁ Dynamic Stress Computations
⦁ Power Train Vibration Analysis
⦁ Shock Calculations per NAVSEA, DDAM, MIL STD

Non-Linear Analysis

⦁ Material Non-linear Analysis
⦁ Geometric Non-linear Analysis
⦁ FEA of Rubber & Elastomers
⦁ Non-linear Dynamic Analysis
⦁ Time Domain Response Analysis
⦁ Impact Analysis
⦁ Thermo-mechanical Analysis involving large displacements
⦁ Elasto-plastic Deformation Analysis.

Analysis of Composites

⦁ Failure mode prediction of Composite panels
⦁ Filament Wound Composite – Anisotropic material modeling
⦁ Random Fiber Composites
⦁ Stiffness, Deflection and Critical Load calculation of Composite Structures
⦁ Metal Matrix Composites – Thermo mechanical Analysis.

Thermal Analysis

⦁ Thermal Stress Analysis of parts and assemblies
⦁ Transient Thermal Analysis
⦁ Thermo-mechanical Analysis
⦁ Coupled Thermo-fluid analysis
⦁ Natural and Forced Convection Analysis
⦁ Non-Linear Thermal analysis of curing processes
⦁ Creep Analysis

Fatigue Analysis

⦁ Remaining Life Analysis (RLA )
⦁ Durability Analysis
⦁ Failure Prediction Analysis
⦁ High Cycle Fatigue Calculations
⦁ Correlation to Real-world situations
⦁ Comparison of Alternate materials for extended life and warranty
⦁ Life extension analysis

CFD Fluid Flow Analysis

⦁ Pressure Drop Calculations
⦁ Conjugate Heat Transfer Analysis
⦁ Electronic Cooling Analysis
⦁ Thermal Efficiency Calculations
⦁ Fluid Flow simulation in Devices such as pumps, valves, ducts, piping networks, fans, diffusers, cyclones, blowers, heat exchangers
⦁ Design optimization based on performance prediction

ASME Stress Analysis

⦁ Stress Analysis per ASME Codes
⦁ Nozzle stress analysis
⦁ Stress Intensity Calculations
⦁ Shell & Full Scale 3D Stress Analysis of Pressure Vessels among others

Design Optimization.

⦁ Optimization of CAD Geometries
⦁ Weight Reduction Analysis
⦁ Value Addition & Value Engineering Analysis
⦁ Sensitivity Based Optimization
⦁ Optimization of design variables based on performance targets

Generator

HVAC Applications : Data Center Velocity Vector and relative humidity

Transformer core

Induction Heating Furnace.

Typical Gas flow diagram.