Multi-scale Modelling: Homogenisation Introduction

LuxuryConceptualArt avatar
LuxuryConceptualArt
·
·
Download

Start Quiz

Study Flashcards

29 Questions

What is the purpose of the Mean Field Method in predicting the behavior of heterogeneous materials?

To give an efficient way of prediction, though not entirely accurate

In the context of elasticity, what do Voigt and Reuss estimates represent?

Isostrain and Isostress conditions

What do Voigt and Reuss estimates assume regarding the conditions among the phases?

Isostrain and Isostress conditions, respectively

How does the Mean Field Method handle the prediction of behavior in heterogeneous materials compared to other methods?

It offers an efficient way of prediction, though not entirely accurate

In the context of composite materials, what is the role of a shape factor in representing interactions between matrix and inclusions?

Representing the spherical nature of inclusions

Why are Voigt and Reuss estimates considered simple mean-field schemes?

For assuming isostrain and isostress conditions among phases

What is the primary aim of homogenisation in computational engineering?

To determine effective macroscopic properties

Why do heterogeneities in a material cause high frequency oscillations in the solution?

Due to the material's inner structure

What key role does the Representative Volume Element (RVE) play in homogenisation?

Calculating average stress and strain

Which mathematical concept is used to connect the interior of the RVE with its boundaries in homogenisation?

Divergence Theory

In homogenisation, what do we aim to obtain about a heterogeneous material?

Effective macroscopic properties

How does direct numerical study typically handle the behavior of heterogenous materials?

By ignoring high frequency oscillations

What concept does Eshelby's work on elastic ellipsoidal inclusions address?

Deformation of inclusions within a matrix

Which operation involves 'cutting out' the inclusion to allow it to deform freely?

Eigenstrain application

In Eshelby's work, what happens during the 'Inclusion Reinsertion' operation?

A compensating stress is applied to restore the inclusion to its original shape

Which material has the highest tensile strength among the ones listed?

Carbon Fibre

What property do Modulus and Tensile strength measure in materials?

Elasticity

In which direction are strength and stiffness generally much higher for composite materials?

Along the fiber direction (isostrain)

According to Reuss estimation, what is the relationship between Composite Load (Pc), Matrix Load (Pm), and Fiber Load (Pf)?

Pc = Pm + Pf

What is Voigt's estimation known as?

Isostrain

Which of the following equations represents Composite Elongation (∆Lc) in the direction of loading correctly?

$∆Lc = ∆Lm + ∆Lf$

What does Voigt's estimation state about the load carried by the composite?

It is equal to the sum of Matrix Load and Fiber Load

According to the extreme conditions stated, what do Isostrain and Isostress represent in composite materials?

Extreme conditions for strength and stiffness

In homogenisation, what does the effective behavior define?

The behavior of a heterogeneous material at a macroscopic level

What method is used to solve the field equations for deriving the localization tensor in homogenisation?

Green's function methods

What does the local perturbation in the strain field represent in homogenisation?

Fourth-rank localisation tensor

When applying boundary conditions in RVE, what are we trying to understand?

How the RVE behaves as part of a larger structure

What is the primary purpose of replacing coefficient tensor A(y) by effective homogenous coefficients in homogenisation?

To make the system computationally cheaper

Does the effective behavior ( ext{𝐂𝐂 𝐞𝐞𝐞𝐞𝐞𝐞}) depend on the length of RVE and boundary conditions?

Yes, it depends on both

Learn about homogenisation in computational engineering for physical systems. Explore the method used to determine effective macroscopic properties of heterogeneous materials and how it simplifies complex material properties into average values.

Make Your Own Quizzes and Flashcards

Convert your notes into interactive study material.

Get started for free
Use Quizgecko on...
Browser
Browser