The paper reviews recent research and development activities in the field of hydropower
technology. It covers emerging and advanced technologies to mitigate flow instabilities …

Hydropower refers to energy conversion from flowing water into electricity. Due to water
recycling by the Sun, hydropower is widely accepted as a form of renewable energy. A …

The synchronous pressure surge effect is a critical phenomenon occurring in Francis
turbines operating at part load conditions. In this regime, pressure fluctuations are …

This review addresses the current state of research into active control and suppression of
vortex rope in hydroturbines under off-design operating conditions. Only active control …

Hydropower plants provide an asset over other renewables of production flexibility. Away
from the turbine design point; detrimental off-load instabilities may compromise the power …

Vortex rope causes instabilities in hydro-turbines and marine turbines. It is an important
issue in the utilization of ocean energy. The flow energy dissipation (FED) is one of …

The off-design operation of Francis turbines results in the onset of flow instabilities. These
instabilities lead to severe pressure pulsations, power swings, fatigue damage, and torque …

The mitigation of the precessing vortex core developing in the draft tube of Francis turbines
operating under part load conditions is crucial to increase the operation flexibility of these …

Operating Francis turbines over extended range is often hindered by the flow instabilities
developed downstream the runner, in the draft tube cone. The unsteady pressure field …

In this paper, we introduce a novel passive control method to mitigate the unsteadiness
effects associated to the swirling flows with self-induced instabilities. The control method …