Methodology to determine a tip-loss factor for highly loaded wind turbines

Sven Schmitz, David C. Maniaci

Research output: Contribution to journalArticle

6 Citations (Scopus)

Abstract

The commonly observed overprediction of tip loads on wind-turbine blades by classical blade-element momentum theory is investigated by means of an analytical method that determines the exact tip-loss factor for a given blade flow angle. The analytical method is general and can be applied to any higher-fidelity computational method such as freewake methods or computational fluid dynamics analyses. In this work, the higher-order free-wake methodWindDVE is used to compute tip-vortex rollup and wake expansion in the near wake of a highly loaded wind-turbine rotor. The resulting spanwise distributions of the blade flow angle serve as input to the analytical method that is subsequently tested for the National Renewable Energy Laboratory phase 6 rotor by implementing a corrected tip-loss factor into the blade-element code XTurb. It is found that a simple modification can be added to the classical tip-loss factor in blade-element momentum theory that leads to improved prediction of blade tip loads at no additional computational expense.

Original languageEnglish (US)
Pages (from-to)341-351
Number of pages11
JournalAIAA journal
Volume55
Issue number2
DOIs
StatePublished - Jan 1 2017

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Wind turbines
Turbomachine blades
Momentum
Rotors
Computational methods
Computational fluid dynamics
Vortex flow

All Science Journal Classification (ASJC) codes

  • Aerospace Engineering

Cite this

Schmitz, Sven ; Maniaci, David C. / Methodology to determine a tip-loss factor for highly loaded wind turbines. In: AIAA journal. 2017 ; Vol. 55, No. 2. pp. 341-351.
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Methodology to determine a tip-loss factor for highly loaded wind turbines. / Schmitz, Sven; Maniaci, David C.

In: AIAA journal, Vol. 55, No. 2, 01.01.2017, p. 341-351.

Research output: Contribution to journalArticle

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