Ecodesign optimisation

1.4 Ecodesign flow-chart

The objective is characterised by an optimisation of the ecodesign function, in which the Q-

H-E aspects all interact together (probability of the event F ). The optimisation process is represented by a flow-chart and illustrated in Figure 6. The analysis of data after each loop for the stage k=1 will be iterated for the other stages involved in the design process (k=2,…/N). For instance, if the final probability output results are close to unity, then the objective previously outlined in Figure 2c is fully reached! However, if the output results are not close to the objective required by the ecodesign standards, we need to search for possible new alternatives. These alternatives can be provided by practical variation of the elements xk, yk and zk.

1.5 Example of alternative solution

To illustrate the procedure of optimisation, let us consider for example stage k involved in the design process and let the subscript k=4 characterising for instance the sentence "open – mould polymerisation process" for which we assume that the "quality assurance aspect" and the

Ecodesign optimisation

Fig. 5. Process flowchart for ecodesign of FRP composite product

"health protection aspect" symbolised respectively by "x4" and “y4‘ are achievable and sustainable; whereas the "environmental preservation aspect", symbolised by “z4" is unachievable for such a manufacturing process (open-mould). This means that the elements x4 and y4 belong simultaneously to both sets Q and H; and therefore they belong to subset B (x4e B and y4e B) as illustrated in Figure 6. However, the element z4 does not belong to sets Q and H (z4 ( Q and z4 ( H) but it belongs to set E; so it belongs to subset S. In order to

realise the event F, the element z4 must be altered in practice to become a new element satisfying the following statement ‘‘environmental preservation aspect is achievable and sustainable for closed-mould polymerisation process”. With this alternative solution, achieved by a modification of the moulding process from open-mould to closed-mould, the three elements

x4, y4 and z4 related to stage 4 now belong to subset F (Figure 6). Further alterations of these elements are possible in practice to reach the maximum limit target and to fully satisfy the ecodesign requirements.

As discussed previously, if we let ‘‘z/’ denotes the statement "environmental preservation aspect is unachievable for polyester resin with high-styrene-content”, this can be practically changed to yield a new element satisfying the statement ”environmental preservation aspect is achievable for polyester resin with low-styrene-content". By replacing "high-styrene-content" with “low-styrene-content", this gives a new “z{‘ that satisfies the ecodesign requirements.

Ecodesign optimisation

Fig. 6. Example of alternative solution related to stage 4