Three dimensional nonlinear simulation, sensitivity analysis and increasing the maximum frequency to 2.5 Hz using a physics-based method for basins in Ottawa, Canada

Abstract. Coastal hydrodynamics can be greatly affected by the presence of submerged aquatic vegetation. The effect of vegetation has been incorporated into the Coupled Ocean–Atmosphere–Wave–Sediment Transport (COAWST) modeling system. The vegetation implementation includes the plant-induced three-dimensional drag, in-canopy wave-induced streaming, and the production of turbulent kinetic energy by the presence of vegetation. In this study, we evaluate the sensitivity of the flow and wave dynamics to vegetation parameters using Sobol' indices and a least squares polynomial approach referred to as the Effective Quadratures method. This method reduces the number of simulations needed for evaluating Sobol' indices and provides a robust, practical, and efficient approach for the parameter sensitivity analysis. The evaluation of Sobol' indices shows that kinetic energy, turbulent kinetic energy, and water level changes are affected by plant stem density, height, and, to a lesser degree, diameter. Wave dissipation is mostly dependent on the variation in plant stem density. Performing sensitivity analyses for the vegetation module in COAWST provides guidance to optimize efforts and reduce exploration of parameter space for future observational and modeling work.

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THREE-DIMENSIONAL DESIGN SENSITIVITY ANALYSIS USING A BOUNDARY INTEGRAL APPROACH

International Journal for Numerical Methods in Engineering ◽

10.1002/(sici)1097-0207(19970228)40:4<637::aid-nme83>3.0.co;2-u ◽

1997 ◽

Vol 40 (4) ◽

pp. 637-654 ◽

Cited By ~ 1

Author(s):

ZEKI ERMAN ◽

ROGER T. FENNER

Keyword(s):

Sensitivity Analysis ◽

Three Dimensional ◽

Design Sensitivity ◽

Boundary Integral ◽

Design Sensitivity Analysis ◽

Integral Approach

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Error Sensitivity Analysis for Machine Tool Based on Three-Dimensional Vector Chain

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.457-458.1562 ◽

2013 ◽

Vol 457-458 ◽

pp. 1562-1565

Author(s):

Qiang Huang ◽

Chan Jun Gao

Keyword(s):

Sensitivity Analysis ◽

Machine Tool ◽

Three Dimensional ◽

Error Modeling ◽

Dimensional Vector ◽

Modeling And Analysis ◽

Vector Operation ◽

Error Sensitivity ◽

Space Error ◽

Error Sensitivity Analysis

Error modeling and analysis can provide some important direction to the machining precision control. According to the characteristics of topology structure on machine tool, a space error model of machine tool and detailed modeling method are presented in this paper, which are based on three-dimensional vector chain. Taking a lathe as an example, the application method of this model in error sensitivity analysis is introduced. By this model, the relationship between the relative error of workpiece-tool and each source error can be solved by ordinary vector operation, and the analysis efficiency should be enhanced greatly.

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A Three-Dimensional Coupled Hydrodynamic-Ecological Modeling to Assess the Planktonic Biomass in a Subalpine Lake

Sustainability ◽

10.3390/su132212377 ◽

2021 ◽

Vol 13 (22) ◽

pp. 12377

Author(s):

Wen-Cheng Liu ◽

Hong-Ming Liu ◽

Rita Sau-Wai Yam

Keyword(s):

Water Quality ◽

Sensitivity Analysis ◽

Ecological Model ◽

Three Dimensional ◽

Ecological Status ◽

Coupled Model ◽

Zooplankton Biomass ◽

Subalpine Lake ◽

Depth Water ◽

Temperature Water

In this study, a coupled three-dimensional hydrodynamic-ecological model was developed to comprehensively understand the interaction between the hydrodynamics and ecological status of a lake. The coupled model was utilized to explore the hydrodynamics, water quality, and ecological status in an ecologically rich subalpine lake (i.e., Tsuei-Feng Lake (TFL), located in north-central Taiwan). The measured data of water depth, water temperature, water quality, and planktonic biomass were gathered to validate the coupled model. The simulated results with a three-dimensional hydrodynamic and water quality-ecological model reasonably reproduced the variations in observed water depth, water temperature, water quality, and phytoplankton and zooplankton biomass. Sensitivity analysis was implemented to determine the most influential parameter affecting the planktonic biomass. The results of sensitivity analysis indicated that the predation rate on phytoplankton (PRP) significantly affects the phytoplankton biomass, while the basal metabolism rate of zooplankton (BMZ) importantly affects the zooplankton biomass. Furthermore, inflow discharge was the most important environmental factor dominating the phytoplankton and zooplankton biomass of TFL. This implies that the runoff in the catchment area caused by rainfall and the heavy rainfall induced by climate change may affect the planktonic biomass of the lake.

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A Multi-Fidelity Model for Simulations and Sensitivity Analysis of Piezoelectric Inkjet Printheads

Micromachines ◽

10.3390/mi12091038 ◽

2021 ◽

Vol 12 (9) ◽

pp. 1038

Author(s):

Vinh-Tan Nguyen ◽

Jason Yu Chuan Leong ◽

Satoshi Watanabe ◽

Toshimitsu Morooka ◽

Takayuki Shimizu

Keyword(s):

Sensitivity Analysis ◽

Three Dimensional ◽

Element Model ◽

Geometrical Parameters ◽

Generation Process ◽

Mechanical Coupling ◽

Design Variables ◽

Computational Structural Mechanics ◽

Lumped Element Model ◽

Inkjet Printhead

The ink drop generation process in piezoelectric droplet-on-demand devices is a complex multiphysics process. A fully resolved simulation of such a system involves a coupled fluid–structure interaction approach employing both computational fluid dynamics (CFD) and computational structural mechanics (CSM) models; thus, it is computationally expensive for engineering design and analysis. In this work, a simplified lumped element model (LEM) is proposed for the simulation of piezoelectric inkjet printheads using the analogy of equivalent electrical circuits. The model’s parameters are computed from three-dimensional fluid and structural simulations, taking into account the detailed geometrical features of the inkjet printhead. Inherently, this multifidelity LEM approach is much faster in simulations of the whole inkjet printhead, while it ably captures fundamental electro-mechanical coupling effects. The approach is validated with experimental data for an existing commercial inkjet printhead with good agreement in droplet speed prediction and frequency responses. The sensitivity analysis of droplet generation conducted for the variation of ink channel geometrical parameters shows the importance of different design variables on the performance of inkjet printheads. It further illustrates the effectiveness of the proposed approach in practical engineering usage.

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