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Dear wind farm modelers,
how fast is fast enough?
 
What if high-fidelity models like Large-eddy simulation could be applied for wind farm modelling in the industrial practice? We think this is possible, thanks to modern GPUs and a suitable numerical method like the Lattice-Boltzmann Method.  
We would like to hear about your industry perspective on the use of LES in this short survey: https://lnkd.in/da-pRSns.
Results will be presented at next year’s Wake Conference.

Best Regards,
Henrik Asmuth
Postdoctoral Researcher, Uppsala University

Wind energy researchers and partners, we are looking forward to welcoming you all and give you the latest news from the research front when gathering the Swedish wind energy academy with partners.

Date: October 24-25
Location: Gothenburg

The sessions will include presentations from the fields of planning, siting, turbine technology, operation and maintenance, and system integration.
In addition, the new national Swedish Wind Centre will be launched.

For more practical information and registration
Registration closes October 14.

Here you will find the program

Welcome!
SWPTC, STand UP for Wind, Energiforsk, RISE

Wake Conference 2023

Next Wake Conference, June 20-22 2023! The conference will be held in person on the island of Gotland, Sweden in the world heritage city of Visby. More information on the conference can be found at wakeconference.se

If you are interested in submitting an article and presenting at the conference please note that abstract submissions are accepted until October 31st.

We hope to see you there!

Best regards,
Stefan Ivanell and Jens Nørkær Sørensen
Organizers of Wake Conference 2023

Henrik Asmuth, doctoral thesis defence April 28th 2022.
For more information.

Research: Renewable Energy for Sustainable Island Communities (REACT)
Link to zoom for attendence online: https://uu-se.zoom.us/j/69681684125
Date: 24 Januari 2022
Time: 10.00
Location: B24, Campus Gotland

Project period: December 2021 - December 2023
Project leader: Stefan Ivanell, Uppsala universitet
Founding: Swedish Energy Agency

The complexity of Northern European wind conditions and new grid requirements for wind farm control challenge the state of industrial wind farm modelling. High-fidelity large-eddy simulation (LES) is considered the most accurate tool for such modelling tasks. However, the immense computational demand of the method limits the use of LES to fundamental academic studies. The lattice Boltzmann method (LBM) states an alternative to classical LES approaches and offers a significantly higher computational efficiency. Already now, LBM-LES is replacing lower fidelity models in various industries. This project will close remaining gaps in the wind-energy-specific modelling capabilities of LBM models. The resulting LBM framework will finally bridge the gap between academic high-fidelity modelling and the industrial practice. This holds the potential for notable uncertainty reductions in power and load estimation that will directly benefit a resource and cost-efficient wind power development.

The goal of the project is to develop and validate a GPU (Graphic Processor
Unit)-based LBM-LES (Lattice-Boltzmann Method - Large Eddy Simulation)
model as a basis for a new wind farm modelling framework.

The purpose of this framework is to enable high-fidelity simulations of
wind turbines in typically Swedish conditions that are fast and efficient enough that applications in the industrial practice become feasible. This implies reductions in computational cost of two orders of magnitude when compared to classical LES models.

Here is more information about the project.

Project period: November 2021 - November 2025
Project leader: Kateryna Morozovska, KTH Royal Institution of Technology
Founding: Vinnova

The purpose of the project is to use innovative computational methods and take advantage of physics-informed neural networks (PINNs) to study the ageing of power components in a wind farm and find possible applications for their reuse. The goals of the project are to: - use PINNs to predict the component ageing - study potential good applications for the method - identify methods for monitoring older components to ensure the system´s safety

Expected results: - well-trained PINNs, which help to define and predict ageing of power components in a wind farm - proposed strategies for reuse and upcycling of power components in new applications - discuss possible reliability impacts of the new application Expected effects: - novel end of life management strategies can reduce negative climate impacts of the renewable energy development - Swedish and international businesses will be able to use our methodology to reduce capital investment on wind farms as well as get extra return on investment after wind farm decommissioning

This project has started on the 1st of November 2021 and will continue until the 30th of June 2026. The project will consist of 7 working packages. 1st working package will focus on identifying key assets for the study. WP 2 and 3 will be oriented towards the development of PINN methods and will compose the longest project stage. WP 4,5 and 6 will test the methods on several case studies and suggest possible new applications for the assets as well as give an economic evaluation of the results. WP 7 will focus on communication and dissemination of the project results.

Here is more information about the project.

Published paper in Physics of Fluids 33, 105111 (2021);"Wall-modeled lattice Boltzmann large-eddy simulation of neutral atmospheric boundary layers"

Authors:
Henrik Asmuth; Christian F. Janßen; Hugo Olivares-Espinosa and Stefan Ivanell

Read the paper.

Abstract:
The lattice Boltzmann method (LBM) sees a growing popularity in the field of atmospheric sciences and wind energy, largely due to its excellent computational performance. Still, LBM large-eddy simulation (LES) studies of canonical atmospheric boundary layer flows remain limited. One reason for this is the early stage of development of LBM-specific wall models. In this work, we discuss LBM–LES of isothermal pressure-driven rough-wall boundary layers using a cumulant collision model. To that end, we also present a novel wall modeling approach, referred to as inverse momentum exchange method (iMEM). The iMEM enforces a wall shear stress at the off-wall grid points by adjusting the slip velocity in bounce-back boundary schemes. In contrast to other methods, the approach does not rely on the eddy viscosity, nor does it require the reconstruction of distribution functions. Initially, we investigate different aspects of the modeling of the wall shear stress, i.e., an averaging of the input velocity as well as the wall-normal distance of its sampling location. Particularly, sampling locations above the first off-wall node are found to be an effective measure to reduce the occurring log-layer mismatch. Furthermore, we analyze the turbulence statistics at different grid resolutions. The results are compared to phenomenological scaling laws, experimental, and numerical references. The analysis demonstrates a satisfactory performance of the numerical model, specifically when compared to a well-established mixed pseudo-spectral finite difference (PSFD) solver. Generally, the study underlines the suitability of the LBM and particularly the cumulant LBM for computationally efficient LES of wall-modeled boundary layer flows.

The bi-annual Wake Conference has gathered researchers within the field of wake interaction and flow modelling since more than ten years both on - and offshore. The conference is usually at Uppsala University Campus Gotland, which is located on the island of Gotland in the World Heritage city of Visby. 

Organizers for the conference are Uppsala University (UU) and Technical University of Denmark (DTU). Professor Stefan Ivanell and Professor Jens Nørkær Sørensen.

Read this years published papers:

• 2021.

Previous Wake Conference published papers:

• 2019.
• 2017.
• 2015.

Here you can watch the webbinar about the national strategy for wind power in Sweden March 2021 (only in Swedish).

Project leader: Stefan Ivanell, Uppsala University
Founding: Energy Agency

Project leader: Lennart Söder, Royal Institute of Technology
Founding: Energy Agency

Wind power has grown strongly in recent years and is expected to continue to increase significantly. Solar power is also expected to increase. In a power system, a continuous balance is maintained between production and consumption. In the Nordic power system, this is currently handled mainly by hydropower. With large amounts of wind and solar power, it will be a challenge to maintain this balance.

The system becomes more volatile with changing conditions between different states. Even in this system, the continuous balance between production and consumption must be maintained. At present, in 2020, there are several different support services for balancing, which affect each other: FFR, FCR, aFRR, mFRR, time shift trading etc.

The aim of this project is to estimate future imbalances and the need for support services. These will vary from hour to hour in a future, entirely renewable, electricity generation system. The basic system has much higher consumption, and more flexibility.

Master's programme one-year
Master's programme two-year