An integrated furnace co-simulation methodology based on a reduced order CFD approach

An integrated thermofluid modelling methodology for pulverised fuel fired utility-scale boilers that is computationally inexpensive, fast, and sufficiently accurate would be valuable in an industrial setting. Such a model would enable boiler operators to investigate a range of off-design operating conditions, which includes flexible operation. The aims of this study was: to develop a reduced order computational fluid dynamics (CFD) model of the furnace and radiative heat exchangers that captures all the important particulate effects while using a Eulerian-Eulerian (EE) approach; using the reduced order CFD model to generate a database of results that covers a wide range of operating conditions; to develop a data-driven surrogate model using machine learning techniques; to integrate the surrogate model with a 1-D process model of the complete boiler; and finally to demonstrate the use of the integrated model to investigate flexible operation and off-design operating conditions. The validity of the CFD modelling approach was demonstrated via application to a 2.165 [MWth] lab-scale swirl pulverised fuel burner, as well as to a 620 [MWe] utility-scale subcritical two-pass boiler, both operating at various loads. The results were compared to measured data and a detailed CFD model using the conventional Eulerian-Lagrangian (EL) approach. A computational speed enhancement of 30% was achieved. The data-driven surrogate model uses a mixture density network (MDN) to predict the heat transfer in the furnace and radiative heat exchangers, together with the uncertainty in the predicted values. The integrated model was validated against applicable measured data and then applied to a utility-scale case study boiler to investigate the optimal burner firing positions for low-load operation, as well as to investigate the effects of fuel quality on the overall boiler performance. It was shown that the integrated data-driven surrogate model and 1-D process model can predict the overall thermofluid response of the boiler and the uncertainties associated with it with good accuracy, whilst maintaining a low computational effort when compared to a conventional CFD model coupled to 1-D process model

PUBLIC RELATIONS PARADOX ON DISPLAY: A COMPARATIVE CASE STUDY ANALYSIS OF THE AUTONOMY-DEPENDENCY PARADOX AT A UNIVERSITY ART MUSEUM

This study explores the paradox of autonomy and dependence that is inherent in organization-public relationships. Using a comparative case study methodology the Brigham Young University Museum of Art’s handling of exhibitions that included nude artworks in 1997 and 2004 as examples. The value of this study is that it illustrates how paradoxical tensions can influence the decision-making process in organizations, as well as the ways in which organizations can manage their own behavior and communication in spite of natural tendencies to manage and control stakeholders and publics

Validation of a thermal non-equilibrium Eulerian-Eulerian multiphase model of a 620 MWe pulverized fuel power boiler

The use of a thermal non-equilibrium Eulerian-Eulerian model for the simulation of a 620 MWe power boiler is proposed for capturing the combustion and radiative heat transfer found in the pulverized fuel systems. The models eliminates the use of a Lagrangian reference frame in tracking solid fuel particles thereby reducing the computational expense and time. The model solves the scalar transport for the particle mass, energy and radiation interactions between the pseudo-particle and continuous phases. The goal is to apply the modelling approach to generate a simulation database for different load cases and firing conditions which in turn will be used to study flexible operation. The model is validated against both numerical and applicable site data measurements. It is shown that the model is able to adequately resolve the furnace and superheater wall heat fluxes. Additionally the resolution of the flow field, combustion dynamics and wall fluxes are demonstrated for both an 80% and 60% operational loads. Moreover, it is shown that the Eulerian-Eulerian model results in approximately a 30% computational resource reduction when compared to traditional modelling approaches

An Overview of the Public Relations Function

This book provides an executive review of the ? eld of public relations with a focus on what managers need to know in order to master the function quickly and effectively. Throughout the text, we integrate the academic with the professional by asking, how can an executive use this knowledge to make the most of the public relations function, department, and initiatives in order to help their whole organization be successful? Part I of the book provides the busy manager with the taxonomy of the public relations ? eld, provides research on the theory of public relations, and examines the structure of organizations and where public relations ? ts within that structure. Part II examines how public relations should be conducted in order to achieve maximum results and provides a comprehensive review of public relations strategy, including how to conduct a public relations campaign. Part III discusses the organizational settings most common in public relations: corporate, agency, government, or public affairs and nonpro? t or advocacy groups and the public relations approaches common in each. We review what research ? nds regarding the most excellent ways to manage public relations and the best ways to analyze and address the ethical challenges to be faced in public relations. We occasionally use short case examples to illustrate and apply the main points managers will need to know in order to manage public relations effectively. Throughout this book, we focus on the managerial pursuits in public relations, such as strategic relationship maintenance, segmentation of publics, and conducting research. We offer insight into the managerial activities of issues management, lobbying and advocacy, creating stakeholder relationships, reputation management, ethical counsel, and corporate communication. We examine the most current thought in public relations to help the busy manager master the most important concepts in the ? eld quickly, accessibly, and with an eye toward helping an organization or client achieve the most effective results through cutting-edge, modern, research-based strategic public relations management