Related Papers
Fatigue Analysis of Wind Turbines
Yohannes Regassa
Comparative assessment of dissipated energy and other fatigue criteria
2007 •
Alexander Korsunsky
Amongst a large number of fatigue criteria proposed for the prediction of crack initiation in thermo-mechanical fatigue, various approaches have been found to be particularly useful for certain categories of material over specific domains of temperature and cyclic strain. However, no particular approach appears to give invariably better predictions than others, so that the choice of the lifing model must be based on validation for the relevant circ*mstances.
FATIGUE DAMAGE ESTIMATE COMPARISONS FOR NORTHERN EUROPEAN AND U.S. WIND FARM LOADING ENVIRONMENTS
Neil Kelley
Fatigue Life Estimation of Small Gas Turbine Blisk
IRJET Journal
Coverage of multiaxial fatigue criteria in fatigue limit region
2007 •
Jan Papuga
There is a power of methods aimed at calculation of equivalent fatigue limit for arbitrary multiaxial loading. Although there are so many ways of computation, their thorough mutual comparison in a larger scale is missing. The database project presented in this paper compri se of several databases crowned with the FatLim dat abase, which comprise of a huge number of experimental results and of 18 computational method working in the category mentioned before. The great block of data was acquired using in-house fatigue software PragTic, w hich is offered as a freeware application. The FatLim datab ase follows its philosophy of a simple and non-paid accessibility. Its query tool written in MySQL and PhP all ows to users to evaluate a practical usability of t ested methods on load cases, which the users define. All the issu es covered within this paper are available on the w ebsite www.pragtic.com, structure of which is described he re. © 2007 University of West Bohemia. All rights reser...
Fatigue Analysis of an Outer Bearing Bush of a Kaplan Turbine
2011 •
Doina Frunzaverde
The failure of machine parts often occurs due to variable loads, even though the stress is below the yield strength value. This phenomenon is known as fatigue. Most important factors contributing to decrease of strength to cyclic loads are likely to be constructive, technological and operational [6]. These factors are as follows [6]: constructive factors: shape and dimensions of part and assembling way; technological factors: the material and the surface quality; operational factors: loading type, level of cycle asymmetry, short-term overloads and underloads, jerks, load frequency, temperature, chemical influence of environment. The stages of fatigue damage evolution are: crack initiation, crack propagation and final fracture [7]. In the case of turbines, studies on fatigue of different component parts were made [1], [2], [4]. This paper presents the numerical fatigue analysis of an outer bearing bush of a Kaplan turbine, using SolidWorks software. ANALELE UNIVERSIT ĂłII
Computation of the Load Spectra for the Fatigue Analysis of a Small Wind Turbine
2016 •
Soukaina MOURCHID
Steel Construction
Analysis of fatigue test data to reassess EN 1993‐1‐9 detail categories
2020 •
Thomas Ummenhofer
Applied Sciences
Comparative Fatigue Life Assessment of Wind Turbine Blades Operating with Different Regulation Schemes
Oliver Probst
A comparative evaluation of the fatigue damage occurring in the blades of small wind turbines, with different power regulation schemes, has been conducted for the first time. Three representative test cases were built, one based on stall regulation and two using pitch regulation. The power curves were tuned to be identical in all cases, in order to allow for a direct comparison of fatigue damage. A methodology combining a dynamic simulation of a wind turbine forced by stochastic wind speed time series, with the application of the IEC 61400-2 standard, was designed and applied for two levels of turbulence intensity. The effect of the wind regime was studied by considering Weibull-distributed wind speeds with a variety of parameter sets. Not unexpectedly, in typical wind regimes, stall regulation led to a generally higher fatigue damage than pitch regulation, for similar structural blade design, but the practical implications were smaller than thought previously. Given the need for co...
Calibration of Design Fatigue Factors for Offshore Wind Turbine Support Structure Based on Fatigue Test Database
2020 •
Wangwen Zhao
The concept of Design Fatigue Factors (DFFs) was introduced for providing desired level of safety in structural fatigue design, often associated with damage calculated from S-N curves. Calculation of fatigue damage from S-N curves can be affected by multiple factors, e.g. types of weld class, corrosion condition, loading conditions, stress concentration on different geometries etc. Each of them can be subject to different level of uncertainties. This study intends to recalibrate the DFFs from a detailed reliability analysis by investigating the probabilistic models derived from the database of S-N curves that has been most frequently used in offshore wind industry. The results of such study indicate that the DFFs can be reduced substantially for the corrosive environmental fatigue models from current standards to the same level of target reliability.
