Quantum mechanics

Vibration fatigue

Engineering

Random variable

Aerospace engineering

Statistics

Marine engineering

Power (physics)

Vibration

Flange

Probability distribution

Acoustics

Wind engineering

Mechanical engineering

Wind speed

Physics

Finite element method

Mathematics

Random vibration

Environmental science

Reliability (semiconductor)

Tower

Turbine

Wind power

Probability density function

Structural engineering

Meteorology

Electrical engineering

Structural Safety

It is important to understand the vibration response and fatigue characteristics of the wind turbine structure. The fatigue reliability of the tower flange and bolt is studied in this paper. Firstly, by using the orthogonal expansion method and the Numerical-Theoretical method of random dynamic action, the random fluctuating wind field is expanded into a set of scattered points to calculate the wind load. The numerical calculation of the dynamic response of the wind turbine is verified with the measured data. Then, a fatigue probability calculation method based on the probability density evolution method is proposed. It is an effective method to substitute the fatigue damage D obtained by a rain flow counting method into the probability density evolution equation to solve the probability density of fatigue damage. In the end, a 1.5 MW wind turbine tower was taken as an example for analyzing the fatigue damage of its flange and bolt which considers the wind speed and wind direction distribution. By using the probability density evolution method, the evolution probability density curve clusters of the structural responses can be given accurately and quantitatively; thus, the reliability of the structure under random load can be conveniently obtained.

Fatigue reliability analysis of wind turbine tower under random wind load