## Composite micromechanics

engidesk toolbox for calculating the stiffness of a single layer

Free

• ### Short description

This toolbox calculates the following lamina properties based on fibre and matrix data:

Elasticity properties: young's moduli, shear moduli, poisson's rations

Thermal Properties: Thermal expansion and conductivity, heat capacity

Moisture Properties: Moisture expansion

The object of micromechanics is to calculate the properties of the fiber-matrix composite on the basis of the properties of the fibers and the matrix. This calculation can be done both analytically and numerically- Using the finite element method e.g.

Dozens of formulas (rules of mixture) resulting from the micromechanical analysis, have been published in literature. In this connection, various models for fibre arrangements are assumed. The engidesk toolbox at hand includes the 2 most popular rules of mixture according to Jones and Puck.

### Details

Release

Last Update

Current version

Price

Licence

Language

16.11.2015

07.03.2016

1.1

Free

MIT-Licence

English

01:10

01:07

### Screenshots

Setup of the composite micromechanics toolbox with example results

Usecase example: Composite rules of mixture-app in interaction with the laminate analysis toolbox

• ### Rule of mixture according to Puck

$E_{ t }=\frac{ E_{m } }{ 1-\nu_{ m }^{2 } }*\frac{ 1+0,85*\phi^{ 2 } }{ (1-\phi)^{ 1,25 }+\frac{ E_{ m } }{ (1-\upsilon_{ m}^{ 2 })*E_{ ft } }*\phi}$

Shear modulus parallel transverse

$G_{ 12 }=G_{ 13 }=\frac{ G_{ m } }{ (1-\sqrt{ \nu_{ f }})(1-\frac{ E_{ m } }{ E_{ f22 } }) }$

Shear modulus transverse transverse

$G_{ 23 }= \frac{ G_{ m } }{ (1-\sqrt{ \nu_{ f } })(1-\frac{ G_{ m } }{ G_{ f23 } }) }$

Poissons's ratio parallel transverse

$\nu_{ 12 }=\nu_{ 13 }=\nu_{ f12 }\upsilon_{ f }+\nu_{ m }\upsilon_{ m }$

Poissons's ratio transverse transverse

$\nu_{ 23 }= \frac{ E_{ 22 } }{ 2G_{ 23 } }-1$

Heat capacity

$C=\frac{ 1 }{ \rho }(\upsilon_{ f }\nu_{ f }C_{ f }+\upsilon_{ m}\nu_{ m }C_{ m })$

Thermal conductivity parallel

$K_{ 11 }=\upsilon_{ f }K_{ f11 }+\upsilon_{ m }K_{ m }$

Thermal conductivity transverse

$K_{ 22 }= K_{ 33 }=\left( 1-\sqrt{ \upsilon_{ f } } \right)K_{ m }+\frac{ K_{ m}\sqrt{ \upsilon_{ f } } }{ \left( 1-\sqrt{ \upsilon_{ f } } \right)\left( 1-\frac{ K_{ m } }{ K_{ f22 } } \right)}$

Thermal expansion coefficient parallel

$\alpha_{ 11 }=\frac{ \upsilon_{ f } \alpha_{ f11 }E_{ f11 }+\upsilon_{ m } \alpha_{ m }E_{ m }}{ E_{ 11 } }$

Thermal expansion coefficient transverse

$\alpha_{ 22 }= \alpha_{ f22 }\sqrt{ \upsilon_{ f } }+\left( 1-\sqrt{ \upsilon_{ f } } \right)\left( 1+\upsilon_{ f } \nu_{ m }\frac{ E_{ f11 } }{ E_{ 11 }}\right)\alpha_{ m }$

• ### Name

engidesk GmbH

Since the company’s formation as RWTH Aachen university spin-off in 2012, engidesk GmbH represents a modern and dynamic software house based in Aachen, Germany. The highly committed team of young professionals around the founders Dr. Lars Lambrecht and Marc Branscheid constantly enhances its uniquely innovative development environment for research and development engineers. The engidesk software enables companies & research facilities to make better use of their technical know-how by harmonising and standardising complex calculations across work groups and entire companies. Unique and easy-to-use interfaces allow for the seamless combination and merger of any calculation know-how to single, directly applicable modules – regardless of the original developing system. Above that, the engidesk market place provides knowledge holders with the possibility to commercialise valuable know-how by putting up problem oriented – all compatible – calculation sequences for sale.