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Title: A Solution Method for the Filtered Lifting Line Theory

Journal Article · · Journal of Fluids Engineering
DOI: https://doi.org/10.1115/1.4066296 · OSTI ID:2462703
 [1];  [2];  [3];  [1]
  1. National Renewable Energy Laboratory (NREL), Golden, CO (United States). National Wind Technology Center
  2. Delft Univ. of Technology (Netherlands)
  3. Univ. of Massachusetts, Amherst, MA (United States)

The filtered lifting line theory presents a continuous form of the inviscid momentum equations of flow over a lifting device, such as a wing or rotor blade, using body forces without mathematical singularities. This theory is also consistent with an actuator line representation of a lifting device. In this work, we present a reformulation of the equations in terms of the local flow angle along the line, which allows solving the stand-alone equations using multivariate root-finding algorithms. This approach can be used to obtain a fast, computationally inexpensive solution of the loading distribution along a wing without the need to perform computational fluid dynamic simulations. We study the requirements in terms of resolution in the spanwise direction and establish the criteria for spacing and minimum amount of points required along the blade to obtain converged solutions. The solutions are compared to results from large-eddy simulations, and we observed excellent agreement with less than a percent difference in quantities along the blade between the methods.

Research Organization:
National Renewable Energy Laboratory (NREL), Golden, CO (United States)
Sponsoring Organization:
USDOE Office of Energy Efficiency and Renewable Energy (EERE), Renewable Power Office. Wind Energy Technologies Office
Grant/Contract Number:
AC36-08GO28308
OSTI ID:
2462703
Report Number(s):
NREL/JA--5000-90389; MainId:92167; UUID:ca7cb896-361f-4a67-8219-12e007509859; MainAdminId:73225
Journal Information:
Journal of Fluids Engineering, Journal Name: Journal of Fluids Engineering Journal Issue: 1 Vol. 147; ISSN 0098-2202
Publisher:
ASMECopyright Statement
Country of Publication:
United States
Language:
English

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