These failures commonly attributed to resonance stress of the blades at different stages to certain excitation frequencies.
In fact, all the change in swept rotors tends to be a new characteristic match of blade airfoil at different span, and the re-matching of flow characteristic for blade airfoil determines the stable operation range and the overall performance of swept rotors at design point directly.
Components like GRP trailer leaf springs, springs for railway freight vehicles are addressed, along with heavy loaded joints like stud connections in rotor blade roots at different loading and environmental conditions.
Two approaches have been applied: one is 2D PIV to map the flow separation around the blade sections at different radial positions; and the other is Stereo PIV to conduct a volumetric measurement in the wake field to reveal the tip vortex development and also velocity distribution.
Blade diameter d = 2r is chosen to get optimizing value, such as 0.76, 0.80, 0.82 or 0.86 m, etc. Figure 5 presents the variation of the power efficiency with respect to the blade diameter at different rotational rate w.
In order to improve the performance of the blade at the different altitudes, the optimization process was performed in two steps.
The distal part of these elongated axonemes are more irregular, and have an incomplete radial wall, indicating that the axoneme grows unevenly along the proximo-distal axis with microtubule blades terminating at different distances from the proximal end seen in both the sagittal (Fig. 3DIV) and the cross sectional (Fig. 3DV) views.
Velocity measurements are performed in phase locking to the rotor, in order to resolve the blade wake structure at different working regimes.
There are straight blades, bow blades, different cutter size chains, and special chains for ripping, carving, and other jobs.
Since every blade row is setup to resolve different frequencies the actual Harmonic Balance solution in each of these blade rows is obtained at different instances in time or time levels.
