Finite Element Analysis (FEA) completed confirming no impact on structural integrity
A two-month structural assessment of a propeller blade modified by PressurePoresTM (PP) was concluded in July.
The calculation of hydrodynamic loads and the blade stress assessment were done by performing CFD and Finite Element analyses for high cycle and low cycle fatigue scenarios, according to DNV Class Guideline DNVGL-CG-0039 “Calculation of marine propellers”.
As a result of high cycle fatigue investigation, regarding the safety criteria of the structure, no critical effect of PP on the stress distribution is observed at the root section, 0.6 radius section and the PP section (>0.85 radius section).
For the low cycle fatigue assessment, where the bollard astern operation at maximum rpm is considered, the blade structure satisfies required safety factor limits defined within DNVGL guideline on safety factors. The above safety factors were calculated by utilising the first principal stresses that are accountable for the tensile stresses on the structure, as suggested by DNV.