Rainflow Analysis

A method of representing a random signal by various numbers of sinusoids that would produce the same amount of fatigue damage. Rainflow and related counting methods are two-parameter methods. Typically they preserve information about the mean value as well as the amplitude of each cycle. There are several two-parameter methods. If the load history begins and ends with its maximum peak, or with its minimum valley, all of these give identical counts. In other cases, the counts are similar, but not identical.

The following methods are similar to the rainflow methods:

• Range-pair counting
• Hayes method
• Original rainflow method
• Range-pair-range counting
• Ordered overall range counting
• Racetrack counting
• Hysteresis loop counting

See also: Cycle Counting.