Particle-based evaluations of fish-friendliness in Kaplan turbine operations

Simulating Fish Motion through a Diagonal Reversible Turbine

“…Early approaches involved the simplification of treating a fish trajectory as a flow streamline [13] and deriving pressure or shear stress variation along this path. Newer works involve Lagrangian approaches where the fish is approximated as a particle [17] or a linear arrangement of particles with the Discrete Element Method (DEM) [18]. However, these methods have their shortcomings, mainly related to the simplifications for estimating the fluid-induced forces on the tracked fish.…”

A Design Concept and Kinematic Model for a Soft Aquatic Robot with Complex Bio-mimicking Motion

“…These live tests not only lead to serious injuries or even the death of the probands in many cases, as shown by Pracheil et al [1], but are also very time and cost intensive. Alternative methods are being investigated to replace or reduce the number of live fish tests, like the use of numerical studies, mainly based on computational fluid dynamics, such as those by Müller et al [2], Klopries [3] or Gomez et al [4], as well as deploying passive probes featuring pressure and acceleration sensors to determine the pressure drop and strike force events as a surrogate for fish, such as those carried out by Pauwels et al [5], Tuhtan et al [6] or Fu et al [7]. However, a fish will neither behave as a dot, as it is commonly modeled in the numerics, nor as a passive body, drifting through a turbine like a wooden stick.…”

“…The second core topic is the presentation of the hardware implementation of the propulsion system best fulfilling our requirements (Sect. 4).…”

Fish damage assessment during the passage through traditional and fish-friendly axial-flow pumps with Lagrangian tracking approach

“…By deploying the sensor devices to record the extreme conditions that fish might encounter during the passage through turbines, Fu et al found that most of the severe events occurred in the stay vane/wicket gates and the runner regions (Fu et al, 2016), and Deng et al validated that some advanced turbine designs met the goals of fish friendliness (Deng et al, 2010). The restriction of these filed tests is high-cost and can only be implemented after the turbines have been installed and in operation (Romero-Gomez et al, 2019). More recently, the Computational Fluid Dynamics (CFD) based numerical methods give us deeper insight into the fish damage assessment in hydraulic machinery.…”

“…To overcome the former limitation, Romero-Gomez and Richmond proposed an alternative method to combine CFD with Lagrangian particle tracking approach for the sake of representing the travel of fish. A series of assessments on fish friendliness were carried out respectively in the marine hydrokinetic turbine, Kaplan turbine and hydro-turbine intakes, in terms of strike occurrence, frequency and intensity (Romero-Gomez et al, 2019;Richmond, 2014, 2017) Pumping stations have the reverse operation mode with turbines and therefore the severe fish mortality exists as well, however, the study of Lagrangian variables along the motion trails of fish is fairly scarce in the pump system. In this paper, with the aim of assessing the fish injury in traditional and fish-friendly axial-flow pumps, the Lagrangian tracking approach that takes the fish profile and contact force into account is utilized to shed light on the fish damage.…”