Method for calculating wind turbine wake flow by using two-dimensional Frandsen wake flow model

Abstract

A method for calculating the wind turbine wake flow by using a two-dimensional Frandsen wake flow model is characterized by comprising the following steps: 1) extracting the thrust coefficient CT, the hub height zh and the terrain roughness z0 of the wind turbine; 2) determining a proportionality coefficient beta and a wake flow diffusion coefficient kw; 3) determining the wake flow initial diameter D1 when the wake flow pressure recovers to the incoming flow pressure; 4) determining the wake flow diameter Dw; 5) determining the assumed speed UF of the wake flow area; 6) determining the standard deviation sigma of the Gaussian function; 7) determining a coefficient C of a Gaussian function; 8) determining velocity loss distribution of the wake flow area; (9) determining the speed distribution of the wake flow area. Through the steps, the prediction precision of the flow field of the wake flow area is improved.

Description

Technical field [0001] The present invention relates to the field of wind power generation, and more particularly to a method of calculating a wind turret using a two-dimensional Frandsen latch model, which can be used in wind farm latch evaluation and micro-location. Background technique [0002] The tail effect of the wind turbine is one of the main factors affecting the overall power generation of wind farms. Accurately evaluate the speed distribution of the tail region to optimize the layout of wind farms in the wind farm, and improve the power generation of the wind farm. It is also possible to provide important technical support for the lathe control of the wind farm. At present, the analysis of the lathe model relies on the principle and the advantages such as calculation and so on becoming the most commonly used tail assessment model. The researchers have proposed a variety of analytical tail models, of which Jensen's latch model is the earliest random model, which is bas...

AI Technical Summary

Problems solved by technology

Researchers have proposed a variety of analytical wake models, among which the Jensen wake model is the earliest wake model, which is based on the assumption of mass conservation and constant velocity deficit, and proposes the expression of the velocity deficit in the wake region, However, due to the lack of consideration of the momentum conservation assumption, the prediction accuracy of the model for the wake is not high

For this reason, the researchers developed the Frandsen wake model by considering mass conservation and momentum conservation at the same time, but the model still uses the assumption of constant velocity loss, resulting in a certain deviation between the wind turbine wake calculated by the model and the actual situation

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