Silicon CVD on powders in fluidized bed: Experimental and multifluid Eulerian modelling study

The Computational Fluid Dynamics code MFIX was used for transient simulations of silicon Fluidized Bed Chemical Vapor Deposition (FBCVD) from silane (SiH4) on coarse alumina powders. FBCVD experiments were first performed to obtain a reference database for modelling. Experimental thermal profiles existing along the bed were considered in the model. 3D simulations provide better results than 2D ones and predict silane conversion rate with a mean deviation of 9% compared to experimental values. The model can predict the temporal and spatial evolutions of local void fractions, gas and particle velocities, species gas fractions and silicon deposition rate. We aim at mid term to model FBCVD treatments of submicronic powders in a vibrated reactor since we have performed experiments proving the efficacy of the process to treat submicronic particles

Multifluid Eulerian modeling of dense gas–solids fluidized bed hydrodynamics: Influence of the dissipation parameters

Computational fluid dynamic (CFD) models must be thoroughly validated before they can be used with confidence for designing fluidized bed reactors. In this study, validation data were collected from a fluidized bed of (Geldart's group B) alumina particles operated at different gas velocities involving two fluidization hydrodynamic regimes (bubbling and slugging). The bed expansion, height of bed fluctuations and frequency of fluctuations were measured from videos of the fluidized bed. The Eulerian–Eulerian two fluid model MFIX was used to simulate the experiments. Two different models for the particle stresses—Schaeffer [Syamlal, M., Rogers, W., O’Brien, T.J., 1993. MFIX documentation: theory guide. Technical Report DOE/METC-94/1004 (DE9400087), Morgantown Energy Technology Centre, Morgantown, West Virginia (can be downloaded from Multiphase Flow with Interphase eXchanges (MFIX) website left angle brackethttp://www.mfix.orgright-pointing angle bracket); Schaeffer, D.G., 1987. Instability in the evolution equations describing incompressible granular flow. Journal of Differential Equations 66, 61–74.] and Princeton [Srivastava, A., Sundaresan, S., 2003. Analysis of a frictional–kinetic model for gas–particle flow. Powder Technology 129(1–3), 72–85.] models—and different values of the restitution coefficient and internal angle of friction were evaluated. 3-D simulations are required for getting quantitative and qualitative agreement with experimental data. The results from the Princeton model are in better agreement with data than that from the Schaeffer model. Both free slip and Johnson–Jackson boundary conditions give nearly identical results. An increase in coefficient of restitution (e) from 0.8 to 1 leads to larger bed expansions and lower heights of fluctuations in the bubbling regime, whereas it leads to unchanged bed expansion and to a massive reduction in the height of fluctuations in the slugging regime. The angle of internal friction (φ) in the range 10–40ring operator does not affect the bed expansion, but its reduction significantly reduces the height of fluctuations

ANATOMICAL AND CLINICAL RELEVANCE OF SIRAVYADHA IN RELATION WITH MARMAS OF UPPER LIMB

The science of Ayurveda is well recognized system of medicine which have unique specialty in the field of Shalyathanthra. The concepts of Ayurveda Shareera evolved 3000yrs ago. Because of generation gap concepts appear to be misinterpreted or not fully developed. At this junction it is our moral duty to take up such studies to understand the concepts clearly and to pass on knowledge to younger generation. It is one of the Para surgical procedure denoting letting of blood outside the body. Different modalities of Rakthamokshana are adopted according to Dosha avastha and Athura avastha. Siravyadha is one of the types of Rakthamokshana by Sasthravacharana. So as to explain its significance a stanza of Su.Sha 8/23 is sufficient. Acharya Sushrutha has given same importance of Dosha to Raktha also, where in many places he has classified many diseases as Rakthaja also. Siravyadha is often recommended as Shodhana chikitsa for such diseases. In the Sushruta Samhita Sharirastana 8th Chapter particular anatomical sites especially the Marma sthanas are recommended as anatomical landmarks for Siravyadhana in Particular diseases. So this study helps to explore the Anatomical & Clinical relevance of Siravyadha on the basis of available literatures. So a creative and logical approach has been done to locate Siras for Siravyadha in Particular disease with Pathophysiological interpretation. So it can be concluded that Siravyadha is effective modality of treatment in many diseases. So the study taken up here is Anatomical and Clinical Relevance of Siravyadha in Relation with Marmas of Upper Limb

HIGH PERFORMANCE COMPUTING: CLEAN COAL GASIFIER DESIGNS USING HYBRID PARALLELIZATION

One of the targets for coal gasification in the near future is capturing 90% of the carbon with less than a 10% increase in cost of electricity. Aggressive goals like this will require innovative gasifier designs to reach the market place quickly, with less risk, and in an economically viable way. Researchers at the National Energy Technology Laboratory (NETL) are collaborating with industry, academia, and other national labs on multiphase computational models like the legacy code MFIX (Multiphase Flow with Interphase eXchange) which can help design, operate, and scale-up clean coal gasifiers to meet the challenges or a carbon constrained world. In fact, NETL has hosted a series of multiphase workshops which has produced a multiphase flow science technology roadmap to achieve the goal “that by 2015 multiphase science based computer simulations play a significant role in the design, operation, and troubleshooting of multiphase flow devices in fossil fuel processing plants”. In this study, we present our experience of porting MFIX, an open source multiphase computational fluid dynamic model, to a high performance computing platform and how the resulting high fidelity simulations are impacting the design of clean coal gasifiers of tomorrow. Inherent to these gasifiers is the various time and length scales which require very high spatial resolution, large number of iterations with small time-steps to resolve and predict the spatiotemporal variations in gas and solids volume fractions, velocities, temperatures with any associated phase change and chemical reactions. These requirements resulted in perhaps the largest known simulations of gas-solids reacting flows, providing detailed information about the gas-solids flow structure, pressure, temperature and species distribution in the gasifier. From a computational science perspective, we found that global communication has to be reduced to achieve scalability to 1000s of cores and hybrid parallelization can yield substantial improvement in time-to-solution when utilizing thousands of multi-core processors

DEVELOPMENT OF TECHNOLOGIES AND ANALYTICAL CAPABILITIES FOR VISION 21 ENERGY PLANTS

A software design review meeting was held May 2-3 in Lebanon, NH. The work on integrating a reformer model based on CFD with a fuel cell flow sheet was completed (Task 2.0). The CFD database design was completed and the database API's finalized. A file -based CFD database was implemented and tested (Task 2.8). The task COM-CORBA Bridge-I was completed. The bridge now has CO interfaces for transferring reaction kinetics information from Aspen Plus to Fluent (Task 2.11). The capability for transferring temperature-dependent physical properties from Aspen Plus to Fluent was implemented (Task 2.12). Work on ''Model Selection'' GUI was completed. This GUI allows the process analyst to select models from the CFD database. Work on ''Model Edit'' GUI was started (Task 2.13). A version of Aspen Plus with the capability for using CO parameters in ''design spec'' analysis has become available. With this version being available, work on adding CO wrapper to INDVU code has been started (Task 2.15). A preliminary design for the Solution Strategy class was developed (Task 2.16). The requirements for transferring pressure data between Aspen Plus and Fluent were defined. The ability to include two CFD models in a flow sheet was successfully tested. The capability to handle multiple inlets and outlets in a CO block was tested (Task 2.17). A preliminary version of the Configuration Wizard, which helps a user to make any Fluent model readable from a process simulator, was developed and tested (Task 2.18). Work on constructing a flow sheet model for Demo Case 2 was started. The work on documenting Demo Case 2 is nearing completion (Task 3.2). A Fluent heat exchanger model was installed and tested. Work on calibrating the heat exchanger model was started (Task 4.1). An advisory board meeting was held in conjunction with the Fluent Users Group Meeting on Monday, June 10, 2002. The meeting minutes and presentations for the advisory board meeting have been posted on the project website (Task 5.0). A paper entitled ''Integrated Process Simulation and CFD for Improved Process Engineering'' was presented at the European Symposium on Computer Aided Process Engineering-12, May 26-29, 2002, The Hague, The Netherlands (Task 7.0)

DEVELOPMENT OF TECHNOLOGIES AND ANALYTICAL CAPABILITIES FOR VISION 21 ENERGY PLANTS

DOE Vision 21 project requirements for the support of Global CAPE-OPEN Reaction Kinetics interfaces in Aspen Plus 12 was written (Task 2.4). The software design document was written and posted on the project web site. Intergraph started work on a proof of concept demo of the physical domain software (Task 2.6). The COM-side (Aspen Plus) and CORBA-side (Fluent) pieces of the Vision 21 controller code were written and independently verified. The two pieces of the code were then combined. Debugging of the combined code is underway (Task 2.7). Papers on fuel cell processes were read in preparation for developing an example based on a fuel cell process (Task 2.8). The INDVU code has been used to replace the boiler component in the Aspen Plus flowsheet of the RP&L power plant. The INDVU code receives information from Aspen Plus and iterates on the split backpass LTSH bypass and excess air quantities until the stipulated superheat outlet temperature is satisfied. The combined INDVU-Aspen Plus model has been run for several load conditions (Task 2.14). Work on identifying a second demonstration case involving an advanced power cycle has been started (Task 3.2). Plans for the second Advisory Board meeting in November were made (Task 5.0). Intergraph subcontract was signed and work on a physical domain software demo was started. A second teleconference with Norsk Hydro was conducted to discuss Global CAPE-OPEN standards and issues related to COM-CORBA Bridge (Task 7.0)

THE IMPACT OF SUSTAINABLE BRANDING USING BIG DATA AND BUSINESS ANALYTICS IN THE MARKET RESEARCH INDUSTRY

Abstract Aim: The research aimed to explore how sustainable branding and big data analytics could enhance brand equity and sustainability in the market research industry. It reviewed existing literature, analysed branding strategies of data-driven companies, identified key attributes for sustainable positioning, used qualitative research methods to investigate competitive advantage, and created a theoretical framework to demonstrate how sustainable branding could improve performance in data-driven companies using big data and analytics. Methodology: This research used qualitative methods for a systematic review of sustainability, branding, and business analytics in the market research industry. It involved semi-structured interviews with 38 senior managers and directors from 24 companies across 8 countries. Despite the impact of COVID-19 on data collection due to changes in working patterns, this study showcased the potential of modern qualitative methods such as the 'inductive a priori' model. It utilized advanced technologies and multi-disciplinary research to tackle complex industry concepts. The research sought to bring about sustainable change in the market research industry. Results: The results of the study indicated that sustainable branding was positively related to consumer behaviour, corporate reputation, and financial performance. Big data and business analytics offered valuable insights into consumer preferences, attitudes, and behaviour which helped companies to develop and manage successful sustainable branding strategies. The study provided a comprehensive framework for understanding the role of sustainable branding, big data, and business analytics in the market research industry. Contribution to knowledge: The contribution of the study lies in identifying the importance of sustainable branding and its relationship with big data and business analytics. The study highlighted the potential benefits of integrating sustainability practices into branding strategies and suggested practical implications for companies to adopt sustainable branding approaches. The findings of the study offered insights into the value of big data and business analytics in the market research industry and provided a basis for future research in this field

Multiphase Flow Modeling - Validation and Application CRADA MC94-019, Final Report

For the development and validation of multiphase flow modeling capability, a cooperative research and development agreement (CRADA) is in effect between Morgantown Energy Technology Center (METC) and Fluent Inc. To validate the Fluent multiphase model, several simulations were conducted at METC and the results were compared with the results of MFIX, a multiphase flow code developed at METC, and with experimental data. The results of these validation studies will be presented. In addition, the application of multiphase flow modeling will be illustrated by presenting the results of simulations of a filter back- flushing and a fluidized bed coal gasifier. These simulations were conducted only with MFIX, since certain features needed in these simulations will be available only in the next release of Fluent