Staying at the forefront of hydroelectric technology
Hydro power meets more than half of Canada’s electricity needs. There is a lot riding on making sure hydro-turbines are reliable, efficient and cost-effective. Over the past 20 years, this has become more challenging, says Laval University mechanical engineer Claire Deschênes.
That’s because the addition to electricity grids of intermittent power sources such as solar and wind means hydro must fill in the gap. When the sun shines or the wind blows, some turbines may stand idle. But they must be ready to plug back into the grid when the wind stops or clouds obscure the sun. In addition, Canada exports electricity to the United States on short term contracts requiring turbines to start and stop frequently.
All of this stopping and starting creates vibrations and stresses that are hard on turbine blades and other mechanical components. “Such operations induce turbulent and damaging flow conditions affecting mechanical components, leading to premature failure and consequently to production losses and increased maintenance cost,” says Deschênes.
But by analysing these turbulent and transient 3D flow patterns with computer simulations, her team is helping turbine manufacturers and hydro-utilities to adapt. Deschênes’s turbine simulations aim to solve complex equations describing the water’s motion over several million points in space and several thousand points in time. These are some of the most demanding flow simulations in engineering, requiring huge amounts of storage space and advanced computing.
“This is important work because it may in turn ease the integration of new renewable energy sources into the power grid,” says Deschênes.