A better design for the turbines of the future

An Industrial Chair between General Electric and the LEGI* is going to put the YALES2HYDRO turbulence simulation code, developed at the laboratory, to good use in designing new generations of hydro turbines that are better adapted to the current demands of the power grids.
In Etruscan mythology, Nethuns was the god of water. At the LEGI, it’s the name of the ANR’s** new Industrial Chair which has been signed for a four-year term with General Electric Hydro France. The Chair for the ‘New Development of Hydro Turbines Using a New Simulation Tool’ (NETHUNS, in French) aims to promote the development of new turbine designs that are tailored to the networks’ current demands.

Hydroelectric turbines are now the most versatile way to balance the needs of the electrical network, which has to accommodate an increasingly large share of intermittent energy sources (such as wind and solar power).

“At all times, it must be possible to balance production and consumption quickly, either by opening the dams’ floodgates in order to produce energy, or by pumping water from the downstream basin to the upstream basin in order to store surplus energy,” explains Guillaume Balarac, professor at Grenoble INP - Ense3, UGA, researcher at the LEGI and holder of the Chair. “This demand for flexibility imposes operating speeds on the turbines for which they were not originally designed. To allow them to operate over a wider rev range, their design must be reviewed so as to adapt them to the turbulence generated by these new speeds.”

 
turbine pompe balarac

But in order to do that, you have to be able to simulate this turbulence - and that’s where the LEGI researchers come in. “The rotational speeds at which the turbines now have to operate are a lot more unstable than the rated speeds, and the simulation strategies conventionally used are incapable of predicting them,” the researcher explains. “That is why we have developed more advanced turbulence simulation strategies that are capable of anticipating hydrodynamic instability. As we do not have the necessary computing power to predict turbulence of all levels, we are compromising by seeking to accurately simulate only the most influential eddies.”

This project is part of the national YALES2 project, coordinated by the CNRS, which helped to simulate the transport of SARS-Cov 2 in the air a few months ago. YALES2 will be implemented in its ‘hydro’ form at General Electric to help the engineers design more robust turbines. At the same time, the researchers at the LEGI will further develop the code in order to make the computing time compatible with industrial requirements. The NETHUNS Chair has received a total of 1 million euros in funding.

*CNRS, Grenoble INP - UGA, UGA, Ministry of Higher Education and Research
**French National Research Agency


Credits photos : Illustration des structures turbulentes dans une simulation instationnaire d'une roue de turbine Francis. Crédit : F. Doussot, LEGI, 2019.
Illustration des structures turbulentes dans une simulation instationnaire de l'ensemble d'une Turbine-Pompe. Crédit : G. Balarac, LEGI, 2021.