FKM Guideline - SimFat - Fatigue evaluation tool

Rewrite of FKM damage potential to Palmgren-Miner rule for Damage

When evaluating with the FKM guideline, fatigue results can also be shown as damage. The damage sum is calculated based on the FKM damage potential, $v_{z d}$ .

The Palmgren-Miner damage rule can be written as;

$D = \sum_{i = 1}^{n} \frac{n_{i}}{N_{i}}$

And if we say;

$∆ {σ_{i}}^{m} \times N_{i} = ∆ {σ_{L}}^{m} \times 10^{6} ⇓ N_{i} = {(\frac{∆ σ_{L}}{∆ σ_{i}})}^{m} \times 10^{6}$

Then the damage sum can be rewritten to;

$D = \sum_{i = 1}^{n} \frac{n_{i}}{10^{6}} \times {(\frac{∆ σ_{i}}{∆ σ_{L}})}^{m}$

FKM damage potential;

$v_{z d} = \sqrt[m]{\sum_{i = 1}^{n} \frac{n_{i}}{H} \times {(\frac{∆ σ_{i}}{∆ σ_{1}})}^{m}} ⇓ {v_{z d}}^{m} = \sum_{i = 1}^{n} \frac{n_{i}}{H} \times {(\frac{∆ σ_{i}}{∆ σ_{1}})}^{m}$

$D = {(v_{z d} \times \frac{Δ σ_{1}}{Δ σ_{L}})}^{m} \times \frac{H}{N_{D σ}}$

Rewrite of FKM damage potential to Palmgren-Miner rule for Damage

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