*2.3.7 Updated finite element model without press cylinder*

Following the results obtained from the analysis of section "A," the finite element model assembly was modified. The new assembly is essentially the same as the original, with the exception that the press cylinder has been removed, and the yoke plates were extended to fill out the space of the press cylinder. The same materials are used for each component. Likewise, the same symmetry conditions and load cases are applied.


#### **Table 2.**

*Composite winding material properties (Zoltek Panex 35 carbon Prepreg [30]).*


**Table 3.** *Symmetry boundary conditions.*

#### *Environmental Impact of Aviation and Sustainable Solutions*


#### **Table 4.**

*Section "A" design configurations test matrix.*

**29**

**Table 5.**

*Section E variations test matrix.*

*Sustainable and Efficient Hydroforming of Aerospace Composite Structures*

**2.4 Finite element models for sections "B," "C," "D," and "E"**

Without the press cylinder component, the yoke plates are in direct contact with the winding frame, so a new frictional contact was added between these two parts,

A similar finite element model and analysis was carried out for the rest of the cross-section designs shown in **Figure 5**. This design aims to determine the effect of the reduced overall cross section height, and different curvatures applied to the main shape of the cross section. However, due to the removal of the press cylinder, the subsequent models were readjusted as previously shown in 2.3.7 & 2.3.8.

In an effort to improve the performance of the promising section "E", additional

designs derived from section "E" were analyzed (**Figure 5**). Moreover, a design matrix (**Table 5**) was constructed based on defined design parameters: composite

*DOI: http://dx.doi.org/10.5772/intechopen.81505*

*2.3.8 Updated contact definition*

**2.5 Variations of section "E"**

shown in **Figure 4b**.

**Figure 5.** *Proposed cross section shapes A, B, C, D, E and E variants.*

### *Sustainable and Efficient Hydroforming of Aerospace Composite Structures DOI: http://dx.doi.org/10.5772/intechopen.81505*
