scholarly journals SIMULATION OF SANDFILL BUILDING STAGES WITH NUMERICAL FLOW MODELS

1986 ◽  
Vol 1 (20) ◽  
pp. 75
Author(s):  
G.J. Bosselaar ◽  
R.A.H. Thabet ◽  
A.J.G.M. Van Roermund ◽  
L. Bijlsma
Keyword(s):  
Large Scale ◽  
Numerical Models ◽  
Flow Patterns ◽  
Two Dimensional ◽  
Integrated Models ◽  
Flow Models ◽  
Test Models ◽  
Physical Scale ◽  
Scale Models ◽  
Closure Operations

The paper describes the application of two dimensional vertically integrated models (WAQUA system) , the results being used for the calculation of sandlosses during sandfill closure operations. Investigations with test models, physical scale models as well as numerical models, are presented to prove that the WAQUA system is not only suitable for large scale applications, but also for the simulation of detailed flow patterns.

scholarly journals FLOW COMPUTATIONS NEARBY A STORM SURGE BARRIER UNDER CONSTRUCTION WITH TWO-DIMENSIONAL NUMERICAL MODELS

1986 ◽  
Vol 1 (20) ◽  
pp. 143
Author(s):  
H.E. Klatter ◽  
J.M.C. Dijkzeul ◽  
G. Hartsuiker ◽  
L. Bijlsma
Keyword(s):  
Numerical Model ◽  
Storm Surge ◽  
Field Data ◽  
Numerical Models ◽  
Flow Patterns ◽  
Scale Model ◽  
Energy Losses ◽  
Local Energy ◽  
Two Dimensional ◽  
Physical Scale

This paper discusses the application of two-dimensional tidal models to the hydraulic research for the storm surge barrier in the Eastern Scheldt in the Netherlands. At the site of the barrier local energy losses dominate the flow. Three methods are discussed for dealing with these energy losses in a numerical model based on the long wave equations. The construction of the storm surge barrier provided extensive field data for various phases of the construction of the barrier and these field data are used as a test case for the computation at methods developed. One method is preferred since it gives good agreement between computations and field data. The two-dimensional flow patterns, the discharge and the head-difference agree well,, The results of scale model tests were also available for comparison. This comparison demonstrated that depth-averaged velocities, computed by a two-dimensional numerical model, are as accurate as values obtained from a large physical scale model. Even compicated flow patterns with local energy losses and sharp velocity gradients compared well.

New Techniques for Measuring Film Cooling Effectiveness

1975 ◽  
Vol 97 (4) ◽  
pp. 539-543 ◽  
Author(s):  
M. F. Blair ◽  
R. D. Lander
Keyword(s):  
Film Cooling ◽  
Large Scale ◽  
Leading Edge ◽  
New Techniques ◽  
Cooling Effectiveness ◽  
Film Cooling Effectiveness ◽  
Rigid Foam ◽  
Test Models ◽  
Scale Models ◽  
Infrared Radiometer

Techniques to measure local film effectiveness distributions on large-scale models of turbine blade and vane sections were developed for use in subsonic, room-temperature wind-tunnel environments. Highly detailed film cooling effectiveness distributions were obtained on near-adiabatic, cast rigid foam test models using infrared radiometer scanning techniques. Sample results from both flat-plate film cooling studies and airfoil leading-edge film cooling studies are presented.

scholarly journals SCALE-MODEL RELATIONSHIP OF BEACH PROFILE

1984 ◽  
Vol 1 (19) ◽  
pp. 95 ◽  
Author(s):  
Masahiro Ito ◽  
Yoshito Tsuchiya
Keyword(s):  
Large Scale ◽  
Scale Model ◽  
Small Scale ◽  
Two Dimensional ◽  
Beach Profile ◽  
Similarity Comparison ◽  
Scale Models ◽  
Reproduction Test ◽  
Experimental Errors ◽  
Relationship Of

This paper presents a scale-model relationship for the similarity between large and small scale-models in two-dimensional equilibrium beach profiles. Taking large scale-models using large scale equipment as prototypes, the experimental scale of a medium-sized model was gradually varied keeping the grain size ratio of model to prototype constant. A similarity-comparison between large and small scale beach profiles is made by considering the degree of experimental errors. Judgement results are graphically shown, and a scale-model relationship is proposed. It is found that the scale-model relationship proposed agrees with the ones derived from the empirical formulae expressing the properties of beach profiles. Additionally, the applicability of this scale-model relationship to the reproduction test of natural beaches is examined.

Post-Wildfire Numerical Modeling for Flood Risk Management

2020 ◽  
Author(s):  
Ian Floyd ◽  
Stanford Gibson ◽  
Gaurav Savant ◽  
Alejandro Sanchez ◽  
Ronald Heath
Keyword(s):  
Shallow Water ◽  
Debris Flows ◽  
Large Scale ◽  
Numerical Models ◽  
The United States ◽  
Water Model ◽  
Sediment Runoff ◽  
Two Dimensional ◽  
Model Framework ◽  
Model Library

<p>The number and intensity of large wildfires in is a growing concern in the United States.  Over the past decade, the National Interagency Fire Centre (NSTC, 2015) reported increases of large fires in every western state in the arid and semi-arid western U.S.  Wildfires, remove vegetation, reduce organic soil horizons to ash, extirpate microbial communities, alters soil structure, and potential development of hydrophobic soils.  These processes all increase water and sediment runoff. Post-wildfire environments can cause a spectrum of hydrologic and sedimentation responses ranging from no response to catastrophic floods and deadly debris flows. Numerical modellers have developed a variety of Newtonian and non-Newtonian shallow-water algorithms to simulate each of these physical processes – making it difficult to model the range of post-wildfire flood conditions and understand model assumption and limitations. This makes a modular non-Newtonian computation library advantageous. This work presents a flexible, numerical model, library framework ‘DebrisLib’ to simulate large-scale, post-wildfire non-Newtonian flows using diverse shallow-water parents code architecture. This work presents the non-Newtonian model framework effectiveness by linking it with two different modelling frameworks, specifically the diffusive-wave one-dimensional and two-dimensional Hydrologic Engineering Center River Analysis System (HEC-RAS), and shallow-water two-dimensional Adaptive Hydraulics (AdH) numerical models. The model library was verified and validated using three flume experiments for mud flows, hyperconcentrated flows, and debris flows under steady and unsteady flow conditions. Additionally the shallow-water model library framework linked with the 1D Hydrologic Engineering Centre Hydrologic Modelling System (HEC-HMS) successfully predicted the 2018 post-wildfire flooding and debris flows following the 2017 Thomas Fire near Santa Barbara, California.</p>

Wind Stress on Water Surfaces

1956 ◽  
Vol 37 (5) ◽  
pp. 211-217 ◽  
Author(s):  
Gerhard Neumann
Keyword(s):  
Wind Tunnel ◽  
Wind Stress ◽  
Large Scale ◽  
Small Scale ◽  
Wind Tunnel Experiments ◽  
Large Lakes ◽  
Flow Models ◽  
Open Sea ◽  
Scale Models ◽  
Bodies Of Water

Various attempts to estimate the total wind stress at the sea surface are briefly reviewed, and the difficulties in the application of the methods used in the past are discussed. The results obtained under natural conditions, that is over larger bodies of water, such as the open sea or large lakes, agree fairly well with each other, whereas great discrepancies are observed with wind tunnel experiments. It is conceivable that the stress values obtained from wind tunnel experiments only hold for the special conditions encountered with small scale flow models. The most important hydrodynamical differences in the flow at both sides of the air-sea interfaces between small scale models and large scale natural bodies of water are pointed out.

scholarly journals A Modular, Non-Newtonian, Model, Library Framework (DebrisLib) for Post-Wildfire Flood Risk Management

2020 ◽  
Author(s):  
Ian E. Floyd ◽  
Alejandro Sanchez ◽  
Stanford Gibson ◽  
Gaurav Savant
Keyword(s):  
Shallow Water ◽  
Large Scale ◽  
Numerical Models ◽  
Geophysical Flows ◽  
Two Dimensional ◽  
Flow Conditions ◽  
Newtonian Flow ◽  
Flume Experiments ◽  
Model Framework ◽  
Newtonian Model

Abstract. Wildfires increase flow and sediment load through removal of vegetation, alteration of soils, decreasing infiltration, and production of ash commonly generating a wide variety of geophysical flows (i.e., hyperconcentrated flows, mudflows, debris flows, etc.). Numerical modellers have developed a variety of Non-Newtonian algorithms to simulate each of these processes, and therefore, it can be difficult to understand the assumptions and limitations in any given model or replicate work. This diversity in the processes and approach to non-Newtonian simulations makes a modular computation library approach advantageous. A computational library consolidates the algorithms for each process and discriminates between these processes and algorithms with quantitative non-dimensional thresholds. This work presents a flexible numerical library framework (DebrisLib) to simulate large-scale, post-wildfire, non-Newtonian geophysical flows using both kinematic wave and shallow-water models. DebrisLib is derived from a variety of non-Newtonian closure approaches that predict a range of non-Newtonian flow conditions. It is a modular code designed to operate with any Newtonian, shallow-water parent code architecture. This paper presents the non-Newtonian model framework and demonstrates its effectiveness by calling it from two very different modelling frameworks developed by the U.S. Army Corp of Engineers (USACE), specifically, within the one-dimensional and two-dimensional Hydrologic Engineering Centre River Analysis System (HEC-RAS) and two-dimensional Adaptive Hydraulics (AdH) numerical models. The development and linkage-architecture were verified and validated using two non-Newtonian flume experiments selected to represent a range of non-Newtonian flow conditions (i.e., hyperconcentrated flow, mudflow, debris flow) commonly associated with post-wildfire flooding.

scholarly journals A Novel Machine Learning Strategy Based on Two-Dimensional Numerical Models in Financial Engineering

2013 ◽  
Vol 2013 ◽  
pp. 1-6 ◽  
Author(s):  
Qingzhen Xu
Keyword(s):  
Machine Learning ◽  
Stock Market ◽  
Large Scale ◽  
Numerical Solutions ◽  
Learning Strategy ◽  
Numerical Models ◽  
Relevant Information ◽  
Future Trend ◽  
Two Dimensional ◽  
Stock Market Index

Machine learning is the most commonly used technique to address larger and more complex tasks by analyzing the most relevant information already present in databases. In order to better predict the future trend of the index, this paper proposes a two-dimensional numerical model for machine learning to simulate major U.S. stock market index and uses a nonlinear implicit finite-difference method to find numerical solutions of the two-dimensional simulation model. The proposed machine learning method uses partial differential equations to predict the stock market and can be extensively used to accelerate large-scale data processing on the history database. The experimental results show that the proposed algorithm reduces the prediction error and improves forecasting precision.

Creating a local food procurement community of practice: The Alberta Flavour Learning Lab

2019 ◽  
Vol 6 (1) ◽  
pp. 155-169 ◽  
Author(s):  
Mary Anne Beckie ◽  
Leanne Hedberg ◽  
Jessie Radies
Keyword(s):  
Community Of Practice ◽  
Large Scale ◽  
Food System ◽  
Local Food ◽  
Provincial Government ◽  
Local Foods ◽  
Social Infrastructure ◽  
City Region ◽  
Physical Scale ◽  
Common Framework

In order for local food initiatives (LFIs) to have a transformative effect on the larger food system, greater levels of economic, organizational and physical scale are needed. One way for LFIs to reach the scale necessary to generate a more significant impact is through increased institutional procurement of local foods. But how do people and organizations come together to generate the social infrastructure required to shift food purchasing practices and processes? This field report shares the story of an innovative community of practice consisting of institutional food buyers, large-scale distributors, regional retailers, processors, producers, researchers, municipal and provincial government representatives within the Edmonton city-region that formed for the express purpose of “creating a positive community impact by getting more local foods on more local plates”. In describing the formation and first three years of the Alberta Flavour Learning Lab we examine the unique characteristics of this community of practice that has aided the development of a common framework for learning, understanding and joint action. In addition to the accomplishments to date, we also discuss the challenges faced by the Learning Lab and the strategies used to overcome them.  

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