CoDA (Composites Design) – Software Licences and Consultancy
CoDA (Composites Design) - Software Licences and Consultancy - supplied by anaglyph
NPL's Composite Design Analysis (CoDA) software is used in aerospace, automotive and construction industries to assist with the preliminary design of material synthesis.
A series of projects has been undertaken over the last few years to aid the introduction and effective use of plastics, and particularly reinforced plastics composites. In every case, the work was carried out in close liaison with industry, often through their membership of a consortium of industrial sponsors. The aim of these projects was to extend current analyses, where necessary, to take account of the specific characteristics of plastics and composites in terms of rate dependence and anisotropy. An essential feature of each programme is the validation of the expressions developed. The outputs are validated procedures, including user-friendly PC software packages, suitable for preliminary design and also for identifying the important material, geometry or support parameters involved.
The identification of the material parameters is equally useful for any subsequent finite element analysis (FEA) undertaken and the analytical relationships developed in the programme have been used to check FEA results. It is an intentional aspect of the work that the output should have an educational aspect, increasing the ability of engineers to appreciate the nature of alternative materials and to design for them in the absence of accumulated experience. The work programmes are described below and similar structural analyses, e.g. on sandwich structures, are being undertaken.
- Material Synthesizer
- Laminate lay-up
- Plate Design
- Beam Design
Composite material synthesiser Laminate lay-up Plate design Beam design. The first two modules were the result of a programme which studied the accuracy of predictions obtained from micromechanics models based on constituent fibre and matrix properties. The predictions were compared with industrially sourced materials that were representative of normal production. The project covered all the major generic composite material classes from injection moulded, chopped strand mat and sheet moulding compounds, through pultrusion and resin injected, to high performance prepregs.
In the absence of easily obtainable components for the high performance prepreg materials, a round-robin on test panel manufacture was undertaken. Test panels fabricated by several establishments from a single batch of pre-preg were tested at NPL and shown to be of a consistently good quality. For other materials a grade was identified and a range of products obtained. In addition, a flat test panel or plaque was obtained for each material. Coupon tests were undertaken both from the test panel and from the products in order to explore the correlation between the measured and predicted properties.
Following this work 'correlation' (or 'reality') functions between theory and experiment were obtained for each property and each class of material. These were used within the software 'prediction' package subsequently developed. The program allows the properties of different classes of material to be predicted. These materials can then be stacked in the lay-up module to give the final laminate properties. The predicted properties can be stored in a database, which can also take input from experimental or manufacturer's results at the material or laminate level. When an experimental database is incomplete it is possible to synthesize the missing data. Thermoelastic and strength properties are predicted in the principal in-plane directions.
The last two modules were developed in projects concerned with using properties, mainly measured from coupons taken from test panels, to predict the performance of experimentally loaded plates or beam structures. All the predictions discussed were similarly validated and the procedures were drawn together and made available in the form of a PC program.
Several areas were explored in the panel programme: rectangular and circular discs; point, line and pressure loads; simple and clamped supports; small and large deflection behaviour; ribbed and sandwich structures; slow rate, creep and high rate loadings.
Similarly, the beam programme investigated different generic beam section shapes (hollow, solid, box, channel, 'T', 'I'); flexural, torsion and mixed loading; straight and stepped beams. For both of these modules data were also measured from the generic beams/plates or from the actual products. Some products were themselves tested under simulated service conditions to validate the strength and stiffness predictions.
For more information, please contact Graham Sims