scholarly journals Impact, Fire, and Fluid Spread Code Coupling for Complex Transportation Accident Environment Simulation

2012 ◽  
Vol 4 (2) ◽  
Author(s):  
Alexander L. Brown ◽  
Gregory J. Wagner ◽  
Kurt E. Metzinger
Keyword(s):  
Liquid Surface ◽  
Computational Method ◽  
Validation Data ◽  
Surface Deposition ◽  
Modeling Methods ◽  
Physical Representation ◽  
Environment Simulation ◽  
The Impact ◽  
Limited Scope ◽  
Existing Data

Transportation accidents frequently involve liquids dispersing in the atmosphere. An example is that of aircraft impacts, which often result in spreading fuel and a subsequent fire. Predicting the resulting environment is of interest for design, safety, and forensic applications. This environment is challenging for many reasons, one among them being the disparate time and length scales that are necessary to resolve for an accurate physical representation of the problem. A recent computational method appropriate for this class of problems has been described for modeling the impact and subsequent liquid spread. Because the environment is difficult to instrument and costly to test, the existing validation data are of limited scope and quality. A comparatively well instrumented test involving a rocket propelled cylindrical tank of water was performed, the results of which are helpful to understand the adequacy of the modeling methods. Existing data include estimates of drop sizes at several locations, final liquid surface deposition mass integrated over surface area regions, and video evidence of liquid cloud spread distances. Comparisons are drawn between the experimental observations and the predicted results of the modeling methods to provide evidence regarding the accuracy of the methods, and to provide guidance on the application and use of these methods.

Fluid Spread Model Validation for Emerging Liquid Tank Impact Predictive Methods

2010 ◽  
Author(s):  
Alexander L. Brown ◽  
Gregory J. Wagner
Keyword(s):  
Liquid Surface ◽  
Computational Method ◽  
Validation Data ◽  
Surface Deposition ◽  
Modeling Methods ◽  
Spread Model ◽  
Predictive Methods ◽  
Physical Representation ◽  
The Impact ◽  
Limited Scope

Transportation accidents frequently involve liquids dispersing in the atmosphere. An example is that of aircraft impacts, which often result in spreading fuel and a subsequent fire. Predicting the resulting environment is of interest for design, safety, and forensic applications. This environment is challenging for many reasons, one among them being the disparate time and length scales that are necessary to resolve for an accurate physical representation of the problem. A recent computational method appropriate for this class of problems has been described for modeling the impact and subsequent liquid spread. Because the environment is difficult to instrument and costly to test, the existing validation data are of limited scope and quality. A comparatively well instrumented test involving a rocket propelled cylindrical tank of water was performed, the results of which are helpful to understand the adequacy of the modeling methods. Existing data include estimates of drop sizes at several locations, final liquid surface deposition mass integrated over surface area regions, and video evidence of liquid cloud spread distances. Comparisons are drawn between the experimental observations and the predicted results of the modeling methods to provide evidence regarding the accuracy of the methods.

scholarly journals Computational Test Design for High-Speed Liquid Impact and Dispersal

2011 ◽  
Author(s):  
Alexander L. Brown ◽  
Kurt E. Metzinger
Keyword(s):  
High Speed ◽  
Water Channel ◽  
Computational Method ◽  
Computational Fluid Mechanics ◽  
Reacting Flow ◽  
Validation Data ◽  
Sled Test ◽  
The Impact ◽  
Scale Data ◽  
Limited Scope

Transportation accidents frequently involve liquids dispersing in the atmosphere. An example is that of aircraft impacts, which often result in spreading fuel and a subsequent fire. Predicting the resulting environment is of interest for design, safety, and forensic applications. This environment is challenging for many reasons, one among them being the disparate time and length scales that must be resolved for an accurate physical representation of the problem. A recent computational method appropriate for this class of problems has been developed for modeling the impact and subsequent liquid spread. This involves coupling a structural dynamics code to a turbulent computational fluid mechanics reacting flow code. Because the environment intended to be simulated with this capability is difficult to instrument and costly to test, the existing validation data are of limited scope, relevance, and quality. A rocket sled test is being performed where a scoop moving through a water channel is being used to brake a pusher sled. We plan to instrument this test to provide appropriate scale data for validating the new modeling capability. The intent is to get high fidelity data on the break-up and evaporation of the water that is ejected from the channel as the sled is braking. These two elements are critical to fireball formation for this type of event involving fuel in the place of water. We demonstrate our capability in this paper by describing the pre-test predictions which are used to locate instrumentation for the actual test. We also present a sensitivity analysis to understand the implications of length scale assumptions on the prediction results.

scholarly journals Process Modeling and Simulation of Tableting—An Agent-Based Simulation Methodology for Direct Compression

Pharmaceutics ◽  
2021 ◽  
Vol 13 (7) ◽  
pp. 996
Author(s):  
Niels Lasse Martin ◽  
Ann Kathrin Schomberg ◽  
Jan Henrik Finke ◽  
Tim Gyung-min Abraham ◽  
Arno Kwade ◽  
...  
Keyword(s):  
Raw Materials ◽  
Pilot Scale ◽  
Physical Models ◽  
Agent Based Simulation ◽  
Validation Data ◽  
Agent Based ◽  
Industrial Processing ◽  
Digital Twins ◽  
Product And Process ◽  
The Impact

In pharmaceutical manufacturing, the utmost aim is reliably producing high quality products. Simulation approaches allow virtual experiments of processes in the planning phase and the implementation of digital twins in operation. The industrial processing of active pharmaceutical ingredients (APIs) into tablets requires the combination of discrete and continuous sub-processes with complex interdependencies regarding the material structures and characteristics. The API and excipients are mixed, granulated if required, and subsequently tableted. Thereby, the structure as well as the properties of the intermediate and final product are influenced by the raw materials, the parametrized processes and environmental conditions, which are subject to certain fluctuations. In this study, for the first time, an agent-based simulation model is presented, which enables the prediction, tracking, and tracing of resulting structures and properties of the intermediates of an industrial tableting process. Therefore, the methodology for the identification and development of product and process agents in an agent-based simulation is shown. Implemented physical models describe the impact of process parameters on material structures. The tablet production with a pilot scale rotary press is experimentally characterized to provide calibration and validation data. Finally, the simulation results, predicting the final structures, are compared to the experimental data.

Review and performance of four models to assess the fate of radionuclides and heavy metals in surface soil

1997 ◽  
Vol 77 (3) ◽  
pp. 333-344 ◽  
Author(s):  
M. I. Sheppard ◽  
D. E. Elrick ◽  
S. R. Peterson
Keyword(s):  
Environmental Impact ◽  
Waste Management ◽  
Chemical Exchange ◽  
Nuclear Industry ◽  
Hydrodynamic Dispersion ◽  
Model Parameters ◽  
Validation Data ◽  
Soil Transport ◽  
And Performance ◽  
The Impact

The nuclear industry uses computer models to calculate and assess the impact of its present and future releases to the environment, both from operating reactors and from existing licensed and planned waste management facilities. We review four soil models varying in complexity that could be useful for environmental impact assessment. The goal of this comparison is to direct the combined use of these models in order to preserve simplicity, yet increase the rigor of Canadian environmental assessment calculations involving soil transport pathways. The four models chosen are: the Soil Chemical Exchange and Migration of Radionuclides (SCEMR1) model; the Baes and Sharp/Preclosure PREAC soil model, both used in Canada's nuclear fuel waste management program; the Convection-Dispersion Equation (CDE) model, commonly used in contaminant transport applications; and the Canadian Standards Association (CSA) derived release limit model used for normal operations at nuclear facilities. We discuss how each model operates, its timestep and depth increment options and the limitations of each of the models. Major model assumptions are discussed and the performance of these models is compared quantitatively for a scenario involving surface deposition or irrigation. A sensitivity analysis of the CDE model illustrates the influence of the important model parameters: the amount of infiltrating water, V; the hydrodynamic dispersion coefficient, D; and the soil retention or partition coefficient, Kd. The important parameters in the other models are also identified. This work shows we need tested, robust, mechanistic unsaturated soil models with easily understood and measurable inputs, including data for the sensitive or important model parameters for Canada's priority contaminants. Soil scientists need to assist industry and its regulators by recommending a selection of models and supporting them with the provision of validation data to ensure high-quality environmental risk assessments are carried out in Canada. Key words: Soil transport models, environmental impact assessments, model structure, complexity and performance, radionuclides 137Cs, 90Sr, 129I

Measuring the Impact of COVID-19 on Businesses and People: Lessons from the Census Bureau’s Experience

2021 ◽  
Vol 111 ◽  
pp. 312-316
Author(s):  
Catherine Buffington ◽  
Jason Fields ◽  
Lucia Foster
Keyword(s):  
Current Population Survey ◽  
Population Survey ◽  
Census Bureau ◽  
Community Survey ◽  
American Community Survey ◽  
Annual Business ◽  
Data Products ◽  
Business Survey ◽  
The Impact ◽  
Existing Data

We provide an overview of Census Bureau activities to enhance the consistency, timeliness, and relevance of our data products in response to the COVID-19 pandemic. We highlight new data products designed to provide timely and granular information on the pandemic's impact: the Small Business Pulse Survey, weekly Business Formation Statistics, the Household Pulse Survey, and Community Resilience Estimates. We describe pandemic-related content introduced to existing surveys such as the Annual Business Survey and the Current Population Survey. We discuss adaptations to ensure the continuity and consistency of existing data products such as principal economic indicators and the American Community Survey.

scholarly journals Impact and Fire Modeling Considerations Employing SPH Coupling to a Dilute Spray Fire Code

2009 ◽  
Author(s):  
Alexander L. Brown
Keyword(s):  
High Speed ◽  
Good Method ◽  
Predictive Tool ◽  
Surface Deposition ◽  
Impact Surface ◽  
Particle Hydrodynamics ◽  
Smoothed Particle ◽  
Model Inadequacy ◽  
The Impact ◽  
Adequate Method

Transportation accidents and the subsequent fire present a concern. Particularly energetic accidents like an aircraft impact or a high speed highway accident can be quite violent. We would like to develop and maintain a capability at Sandia National Laboratories to model these very challenging events. We have identified Smoothed Particle Hydrodynamics (SPH) as a good method to employ for the impact dynamics of the fluid for severe impacts. SPH is capable of modeling viscous and inertial effects for these impacts for short times. We have also identified our fire code Lagrangian/Eulerian (L/E) particle capability as an adequate method for fuel transport and spray modeling. A fire code can also model the subsequent fire for a fuel impact. Surface deposition of the liquid may also be acceptably predicted with the same code. These two methods (SPH and L/E) typically employ complimentary length and timescales for the calculation, and are potentially suited for coupling given adequate attention to relevant details. Length and timescale interactions are important considerations when joining the two capabilities. Additionally, there are physical model inadequacy considerations that contribute to the accuracy of the methodology. These models and methods are presented and evaluated. Some of these concerns are detailed for a verification type scenario used to show the work in progress of this coupling capability. The importance of validation methods and their appropriate application to the genesis of this class of predictive tool are also discussed.

scholarly journals Evaluasi Pelaksanaan Program Pemberdayaan Ekonomi Masyarakat Pesisir (PEMP) Sebagai Upaya Penanggulangan Kemiskinan di Kecamatan Batudaa Pantai Kabupaten Gorontalo

2017 ◽  
Vol 6 (1) ◽  
pp. 30
Author(s):  
Harson Gasim
Keyword(s):  
Poverty Alleviation ◽  
Evaluation Study ◽  
Economic Organization ◽  
Marine Resources ◽  
Selection Mechanism ◽  
Evaluative Study ◽  
The Poor ◽  
Maximum Contribution ◽  
The Impact ◽  
Existing Data

The potential of marine resources that is large enough owned by Gorontalo Regency in reality has not been able to give maximum contribution for improving coastal community welfare. The most dominant issue facing coastal areas is the problem of poverty. The purpose of this study is to find out how far the impact of this PEMP program on poverty alleviation in District Batudaa Pantai Gorontalo. The type of this study is an evaluative study. The type of evaluation study used is a descriptive evaluation of assessing and analyzing data by describing or describing existing data and analyzing the results. The results show that the KMP selection mechanism has not yet given room for participation in decision-making and empowerment of the poor; Disbursement mechanism and fund management less effective, not transparent; Strengthening of socio-economic organization of society not yet effective and process of assistance less than optimal Potensi sumber daya laut yang cukup besar yang dimiliki Kabupaten Gorontalo dalam kenyataannya belum mampu memberikan kontribusi secara maksimal bagi peningkatan kesejahteraan masyarakat pesisir. Persoalan yang paling dominan yang dihadapi wilayah pesisir justru masalah kemiskinan. Tujuan penelitian ini ialah untuk mengetahui seberapa jauh dampak program PEMP ini terhadap penanggulangan kemiskinan di Kecamatan Batudaa Pantai Kabupaten Gorontalo.Adapun tipe penelitian ini merupakan suatu studi evaluatif. Jenis studi evaluasi yang digunakan adalah evaluasi deskriftif yaitu menilai dan menganalisa data dengan cara menggambarkan atau mendeskripsikan data yang telah ada dan menganalisanya Hasil penelitian menunjukkan Mekanisme pemilihan KMP belumlah memberi ruang partisipasi dalam pengambilan keputusan dan pemberdayaan masyarakat miskin; Mekanisme pencairan dan pengelolaan dana kurang efektif, tidak transparan; Penguatan organisasi sosial ekonomi masyarakat belum efektif serta proses pendampingan kurang optimal

scholarly journals IV. Impact with a liquid surface studied by the aid of instantaneous photography. Paper II

1900 ◽  
Vol 194 (252-261) ◽  
pp. 175-199 ◽  
Keyword(s):  
Liquid Surface ◽  
Thin Glass ◽  
Water Line ◽  
Glass Vessel ◽  
Camera Lens ◽  
General Arrangement ◽  
Set Up ◽  
The Impact ◽  
Rough Sphere ◽  
Smooth Sphere

In a previous paper (‘Philosophical Transactions,’ A, 1897, vol. 189, p. 137) we have drawn attention to the fact that the disturbance set up in a liquid by the impact of a rough sphere falling into it, differs in a very remarkable manner from that which follows the entry of a smooth sphere. In the present paper we describe further experiments, made with the object of ascertaining the reason of this difference, and give the conclusions reached. It appeared desirable, in the first place, to take instantaneous photographs of the disturbed liquid below the water-line. These were easily obtained by letting the splash take place in an approximately parallel-sided thin glass vessel (an inverted clock-shade) illuminated from behind. The liquid surface when undisturbed was about level with the middle of the camera-lens, which was focussed for the sphere when under water. The general arrangement of the optical apparatus will be suffi­ciently understood from the accompanying cut (fig. 1). The method of timing the illumination was that already described ( loc. cit. ).

Who Runs for Local Office?

2012 ◽  
Author(s):  
J. Eric Oliver ◽  
Shang E. Ha ◽  
Zachary Callen
Keyword(s):  
Quality Of Life ◽  
Economic Development ◽  
Public Affairs ◽  
Municipal Governments ◽  
Civic Duty ◽  
Chicago Metropolitan Area ◽  
Local Politicians ◽  
The Impact ◽  
Limited Scope

This chapter considers the types of people who run for office and the types of campaigns they run. It examines the impact of factors such as personal ambition, civic responsibility, mobilizing issues, personal gain, and political indignation by looking at a large sample of local politicians (i.e., unsuccessful candidates and elected officials) from the greater Chicago metropolitan area. The small size, limited scope, and low bias of most Chicago-area municipal governments mean that these local politicians, like local voters, tend to be stakeholders in their communities. They are very concerned with issues of economic development and quality of life, yet are drawn into public affairs primarily from a sense of civic duty and an attachment to their towns. They are motivated less by ideology, partisanship, or even personal ambition, than by a public-spirited commitment to sustaining the quality of their communities.

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