In this test we compare the eigenfrequencies of an isolated IEA 15-MW blade given in Table 2.1 of Gaertner et al. (2020) to results obtained in Ashes.

2 Model

The IEA 15-MW blade can be found in the Blade database. The blade is fixed at its root.

3 Benchmarks

In the following sections, the different modeshapes are illustrated and the expected eigenfrequencies as listed in Gaertner et al. (2020) are given.

3.1 First flapwise mode

The expected eigenfrequency is

$$f_1 = 0.555 \text{ Hz}$$

. The mode shape is illustrated in the figure below:

3.2 First edgewise mode

The expected eigenfrequency is

$$f_2 =0.642\text{ Hz} $$

. The mode shape is illustrated in the figure below:

4 Results

The test is considered passed if the results from Ashes are within 5% of the data from the specification document. A bar plot comparing the eigenfrequncies is available on the following link:

https://www.simis.io/downloads/open/benchmarks/current/IEA 15-MW blade eigenfrequencies.pdf