Related Experiment Video
Updated: Jul 12, 2025
09:04
A Modeling and Simulation Method for Preliminary Design of an Electro-Variable Displacement Pump
Published on: June 1, 2022
3.1K
CFD-based design optimization of ducted hydrokinetic turbines.
Jeongbin Park1, Bradford G Knight2, Yingqian Liao3
1Naval Architecture and Marine Engineering, University of Michigan, Ann Arbor, MI, 48109, USA.
Scientific Reports
|October 20, 2023
Summary
Ducted hydrokinetic turbines can significantly boost renewable energy generation. Our study optimized a ducted turbine design, achieving 54% efficiency, a notable improvement over unducted turbines.
Area of Science:
- Renewable Energy Systems
- Fluid Dynamics
- Turbomachinery Design
Background:
- Hydrokinetic turbines harness energy from moving water for sustainable electricity.
- Ducts are hypothesized to enhance turbine efficiency by conditioning fluid flow.
- Empirical evidence for ducted hydrokinetic turbine performance is limited.
Purpose of the Study:
- To optimize the design of a ducted hydrokinetic turbine for maximum energy extraction efficiency.
- To provide substantial evidence for the performance benefits of ducted hydrokinetic turbines.
- To investigate the impact of duct geometry on turbine performance.
Main Methods:
- Computational Fluid Dynamics (CFD) simulations using a blade-resolved Reynolds-averaged Navier-Stokes (RANS) solver.
- A gradient-based optimization approach coupled with the adjoint method to explore the design space.
- Higher-fidelity unsteady Reynolds-averaged Navier-Stokes (URANS) simulations for final design validation.
Main Results:
- An optimized ducted hydrokinetic turbine design was developed.
- The optimized design achieved approximately 54% energy extraction efficiency.
- This represents a significant improvement over the typical 46% efficiency of unducted turbines.
Conclusions:
- Ducting hydrokinetic turbines demonstrably enhances energy extraction efficiency.
- CFD-based optimization is an effective method for designing high-performance ducted turbines.
- The optimized ducted turbine design offers a promising advancement for renewable energy production.
Related Concept Videos
01:21Design Example: Creating a Hydraulic Model of a Dam Spillway
207
Scaled hydraulic models of dam spillways provide a practical way to replicate and study the intricate flow dynamics of these structures. Often built to a 1:15 ratio, these models allow for observing critical water behavior, such as velocity distribution, flow patterns, and energy dissipation.
207
01:30Typical Model Studies
365
Fluid mechanics model studies often utilize scaled-down systems to predict fluid behavior in full-scale environments, such as river flows, dam spillways, and structures interacting with open surfaces. Maintaining Froude number similarity in river models is crucial, as it replicates surface flow features like wave patterns and velocities.
365
01:14Conservation of Energy in Control Volume
845
Consider a turbine operating under steady-flow conditions. The control volume is drawn around the turbine, with fluid entering at one point and exiting at another. The turbine extracts energy from the fluid, which performs mechanical work (shaft work).
For steady flow systems, the time derivative of the stored energy becomes zero since there is no energy accumulation within the control volume. This simplifies the energy equation to:
For steady flow systems, the time derivative of the stored energy becomes zero since there is no energy accumulation within the control volume. This simplifies the energy equation to:
845
01:17Design Example: Calculating Safe Diameter for Wind-Exposed Disc
137
Assessing safety in wind-exposed installations is crucial to preventing potential failures. This example explores the calculation and design adjustments needed to mount a circular disc on a building facade, where wind forces are a primary concern. A 4-meter diameter disc was initially designed as an aesthetic feature facing winds at a velocity of 25 meters per second, with an air density of 1.25 kilograms per cubic meter. Given these conditions, the drag force on the disc was determined using...
137
01:24Rapidly Varying Flow
66
Rapidly varying flow (RVF) in open channels is characterized by abrupt changes in flow depth over a short distance, with the rate of depth change relative to distance often approaching unity. These flows are inherently complex due to their transient and multi-dimensional nature, making exact analysis difficult. However, approximate solutions using simplified models provide valuable insights into their behavior.Key Features of Rapidly Varying FlowRVF is commonly observed in scenarios involving...
66
01:11Design Example: Forces in Sluice Gate
714
In hydraulic engineering, sluice gates are essential for managing water flow through channels, reservoirs, and irrigation systems. Sluice gates, acting as vertical barriers, regulate water by adjusting the gate's opening height, which changes the velocity and pressure of water flowing beneath the gate. Understanding the forces involved is crucial to designing sluice gates that can withstand dynamic pressure differences, especially when the gate is closed or partially open.
Key variables in...
Key variables in...
714