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On September 22, 2022, the National Academy of Sciences held a symposium entitled Endless Frontier 2022: Research and Higher Education Institutions for the Next 75 Years. The event was a follow up to a February 2020 NAS symposium convened to celebrate the 75th anniversary of the landmark report Science, the Endless Frontier. Building on the 2020 symposium and on lessons learned during the COVID-19 pandemic, the September 2022 symposium sought to generate tools, strategies, and actionable steps that people and institutions can implement to ensure that science and technology continue to serve the public good. The symposium was designed to progress from broad perspectives that encompass the entire science and technology enterprise to consideration of more specific issues. This proceedings summarizes the 2022 symposium. [This activity was also supported by the Kavli Foundation. Jeena M. Thomas and Steve Olson served as Rapporteurs. Policy and Global Affairs was a contributor to this report.]

"Proceedings of International Conference on Studies in Education and Social Sciences" includes full papers presented at the International Conference on Studies in Education and Social Sciences (ICSES) which took place on November 11-14, 2021 in Antalya, Turkey. The aim of the conference is to offer opportunities to share ideas, to discuss theoretical and practical issues and to connect with the leaders in the fields of education and social sciences. The conference is organized annually by the International Society for Technology, Education, and Science (ISTES). The ICSES invites submissions which address the theory, research or applications in all disciplines of education and social sciences. The ICSES is organized for: faculty members in all disciplines of education and social sciences, graduate students, K-12 administrators, teachers, principals and all interested in education and social sciences. After peer-reviewing process, all full papers are published in the Conference Proceedings. [Individual papers are indexed in ERIC.]

The article discusses various practical forms of geomodels and how to construct them and discusses procedures to produce block diagrams for important engineering projects.

Over the last two decades, colleges and universities in the United States have significantly increased the formal ethics instruction they provide in science and engineering. Today, science and engineering programs socialize students into the values of scientists and engineers as well as their obligations in the conduct of scientific research and in the practice of engineering. "Practical Guidance on Science and Engineering Ethics Education for Instructors and Administrators" is the summary of a workshop convened in December 2012 to consider best practices for ethics education programs in science and engineering. The workshop focused on four key areas: goals and objectives for ethics instruction, instructional assessment, institutional and research cultures, and development of guidance checklists for instructors and administrators. Leading experts summarized and presented papers on current research knowledge in these areas. This report presents the edited papers and a summary of the discussions at the workshop. Appended are: (1) Biographies; (2) Workshop Agenda; (3) Workshop Participants; and (4) Bibliography of Suggested Resources. (Individual chapters provide references.) [The content of this document was prepared by the Joint Advisory Group to the Center for Engineering, Ethics, and Society (CEES) and the Online Ethics Center (OEC).]

The National Academy of Engineering's 2012 forum, "Educating Engineers: Preparing 21st Century Leaders in the Context of New Modes of Learning," opened with presentations by six speakers who looked at the future of engineering and engineering education from their perspectives as educators, administrators, entrepreneurs, and innovators. Each speaker focused on just one facet of a tremendously complex picture. Yet together they outlined a new vision for engineering education based on flexible, interactive, lifelong learning and the merge of activities long held to be distinct. This summary of a forum recaps the six speaker's presentations.

Since its initial funding by the National Science Foundation in 2004, the National Center for Engineering and Technology Education (NCETE) has worked to understand the infusion of engineering design experiences into the high school setting. Over the years, an increasing number of educators and professional groups have participated in the expanding initiative seeking to acquaint all students with engineering design. While there is strong support for providing students with engineering design experiences in their high school science, technology, engineering, and mathematics (STEM) courses, the lack of consensus on purposes and strategies has become increasingly apparent as the work continues. In February, 2011, NCETE sought position statements from a small number of engineering educators, cognitive scientists, instructional designers, and professional development providers who have been engaged in long-term efforts to provide students with engineering design experiences in their high school STEM courses. Each of these experienced professionals was asked to provide brief descriptions of principles or guidelines that they consider to be most important in promoting effective infusion of authentic engineering design challenges into STEM courses for all high school students. This publication contains the following papers: (1) Design Problems for Secondary Students (David H. Jonassen); (2) Infusing Engineering Design into High School STEM Courses (Morgan Hynes, Merredith Portsmore, Emily Dare, Elissa Milto, Chris Rogers, and David Hammer); (3) Integrating Engineering Design Challenges into Secondary STEM Education (Ronald L. Carr and Johannes Strobel); (4) Design Principles for High School Engineering Design Challenges: Experiences from High School Science Classrooms (Christian Schunn); (5) Engineering Design Challenges in a Science Curriculum (Arthur Eisenkraft); and (6) A Possible Pathway for High School Science in a STEM World (Cary Sneider). (Individual papers contain figures, references and appendices.)

In this symposium, the participants discuss some preliminary data collected from their problem solving project which uses a design experiment approach. Their approach to problem solving in the school curriculum is in tandem with what Schoenfeld (2007) claimed: "Crafting instruction that would make a wide range of problem-solving strategies accessible to students would be a very valuable contribution. This is an engineering task rather than a conceptual one" (p. 541). In the first paper, the participants look at how two teachers on this project taught problem solving. As good problems are key to the successful implementation of their project, in the second paper, they focus on some of the problems that were used in the project and discuss the views of the participating students on these problems. The third paper shows how an initially selected problem led to a substitute problem to meet their design criteria. The papers included in this symposium are: (1) Enacting a Problem Solving Curriculum (Leong Yew Hoong, Toh Tin Lam, Quek Khiok Seng, Jaguthsing Dindyal, Tay Eng Guan and Lou Sieu Tee); (2) Problems for a Problem Solving Curriculum (Jaguthsing Dindyal, Quek Khiok Seng, Leong Yew Hoong, Toh Tin Lam, Tay Eng Guan and Lou Sieu Tee); and (3) Resources for Teaching Problem Solving: A Problem to Discuss (Quek Khiok Seng, Toh Tin Lam, Jaguthsing Dindyal, Leong Yew Hoong, Tay Eng Guan and Lou Sieu Tee). Individual papers contain tables, figures and references. [For the complete proceedings, "Shaping the Future of Mathematics Education. Proceedings of the Annual Conference of the Mathematics Education Research Group of Australasia (33rd, Freemantle, Western Australia, Australia, July 3-7, 2010)," see ED520764.]

This article concerns on overview of today software products for ordinary personal computers and small workstations, gives list of important features relevant to solution of environmental foresighting. For this branch of problems are important not only usual advantages of software packages like computing power, simplicity of use, number of prepared models, but in the first place multidisciplinarity and reliability of gained output. This time there are many software packages prepared for instant use in many branches, this paper describes only few of them and concerns on most known and accessible systems for simulation with partial focus on systems for power engineering problems, which are one of most complex and important problems to be solved. Especially in environmental foresighting there is very high level of complexity of possible systems influence with direct and indirect way. For that reasons there are in this branch many chances to use computer simulations of systems to gain exact overview of future conditions of systems depending of various factors. [ABSTRACT FROM AUTHOR]

"2009 Portfolio: The Second Edition of the College of Engineering's Portfolio" presents the 2009 Faculty Development Program on Teaching & Learning (TL) new content, modified models, new process and procedures, especially the new Instructional Analysis and Design Process Map, new PowerPoint presentations, modified teaching and learning assessment instruments, longitudinal faculty feedback and evaluation results and report and new TL bibliography. This Portfolio presents a complete and comprehensive faculty development program with all program content, models, procedures, tools, instruments, forms, worksheets and PowerPoint presentations. It is extremely easy to use as is or modify. Live files are available from the author. Check http://www.niu.edu/ceet/p20/index.shtml for ongoing updates and new content, 2009 forward, e.g Student Teaming. 2007 Portfolio: This Northern Illinois University College of Engineering and Engineering Technology (CEET) initiative represents the authors' first attempt to prepare engineering and technology professors for teaching to improve student learning and engage faculties in the Scholarship of Teaching. This college portfolio is nontraditional in that it combines a learning paper approach with a literature study, the presentation of two interdependent research endeavors, design and methodology, results, full faculty development program on teaching and learning, content and process, evaluation, and conclusions, recommendations, and many product samples. It presents a selected cross section of the literature on or related to faculty learning communities, teaching and learning and the scholarship of teaching for the faculty research participants. The research and development aspects have two foci: (1) The Effectiveness of a New Faculty Development Model and Program on Teaching and Student Learning and in Preparing Faculty for the Scholarship of Teaching; and (2) Experimental Classroom Research on Teaching and Student Learning as The Scholarship of Teaching. The portfolio contains: (1) Complete Faculty Development Program models; (2) Instruments, Feedback and Evaluation Forms, Program Worksheets; (3) Research Designs, Methodology, and Procedures; (4) Data and Reports; (5) Presentations; and (6) Faculty Products. (Contains 4 separate bibliographies totaling approximately 1,112 bibliographic sources, including hundreds of web site sources.)[For "The Scholarship of Teaching: The CEET Initiative on Teaching and Learning. A Faculty Development Program on Teaching and Learning and Classroom Research. Volumes 1-4. October 2005-December 2006," see ED498370.]

The bulk of Science Fiction (SF) has not predicted the most influential computer technologies of the late 20th century. This paper begins with an exception entitled ˵A Logic Named Joe″ and its accurate description of the contemporary environment of PCs and the World Wide Web. It then proposes the possible historical and cultural value of SF in techno-scientific development - more specifically computer development - in both the U.S. and Finland, and argues that social science approaches to understanding technoscience should take SF into account when describing those communities of practice. [ABSTRACT FROM AUTHOR]

Determining the right requirements to develop a system is crucial as it involved variety of people and it affects the quality of the end product. Different stakeholders have different requirements which they may express in different ways. Naturally, they will express requirements in their own terms and with implicit knowledge of their own work. Generally, stakeholders are not sure of what they want from the computer system except in the most general terms. Hence, conflicts are inevitable. Negotiation is applied to resolve the conflicts and becoming popular nowadays to better improve requirements engineering process. Therefore, this paper is empirically confirming the effectiveness of negotiation effort in order to improve the level of agreement among all the stakeholders. Agreed requirements are believed to represent all the stakeholders' perspectives and perceptions and to obtain a set of unambiguous, correct, complete, consistent and achievable requirements. [ABSTRACT FROM AUTHOR]

Software systems need to evolve, and systems built using model driven approaches are no exception. The role of the models are increasing and becoming more and more important in the software development and evolution. So, the Model-Driven Software Evolution (MoDSE) is prominent. Several stakeholders are involved in the process of evolution. These user groups (stakeholders) have different concerns relevant to the models to be evolved in MoDSE. Multiple views provide a means to visualize complex information and are also a way to fulfill the concerns of different user groups. In this paper the concept of multiple views for the MoDSE is introduced and shows how these multiple views addresses the stakeholders concerns. The different viewpoints are identified to construct the multiple views. This paper also shows an analytical support how the proposed views are closer to the Lehman's laws of software evolution. [ABSTRACT FROM AUTHOR]

This paper focuses on an empirical layout improvement project. In the implementation process of the project, the authors followed an enhanced procedure to increase the involvement of the area experts in the layout design process, which assured the successful realisation of an appropriate layout solution satisfied to both the project team and the top management of a case company. In this paper, the project, the enhanced procedure and the designed new layout for a shop floor in the case company by applying the procedure are introduced, and the summarised evaluation on the new layout and the enhanced procedure is also presented. [ABSTRACT FROM AUTHOR]

The recent years mobile multimedia information gain considerable demand. We propose a model which can be easily addressed in different, interesting applications. In this paper we describe two applications more detailed in order to demonstrate functionality and usefulness of our model. The basic component is the description of real world events and the management of different data types like images, audio, video and texts. [ABSTRACT FROM AUTHOR]

The assimilation of formal logic into the domain of Software Engineering offers the possibility of enormous benefits in terms of software reliability and verifiability. To date, however, the integration of such techniques has proved difficult since they involve a significantly increased burden on the programmer in meeting the demands of the formal mechanisms being employed. The current paper investigates the advantages which may be gained by the software development process with the introduction of Artificial Neural Network technology into a formal software development system. Essentially, the adaptive artificial neural network model is employed to refine an existing formal software model in order to produce increasingly better approximations to a given solution. Each approximation is itself a valid formal system whose precise behaviour may be formally determined. The paper introduces a framework by which a programmer may define a system possessing the abstract structure of a traditional neural network but whose internal structures are taken from the formal mathematical domain of Constructive Type Theory. The system will then refine itself to produce successive approximations to a desired goal based on data presented to it. An example is presented addressing a problem domain which has previously proved difficult to model. Although the example presented is necessarily limited, it does provide an insight into the potential advantages of merging formal logic with artificial neural systems. [ABSTRACT FROM AUTHOR]

This paper examines engineering philosophy in relation to the renewal of aging or outdated infrastructure. The authors test hypotheses concerning standardisation, obsolescence and operational risk using option-pricing models. The results of our study indicates engineering for infrastructure renewal that: • is standardised, • remains relevant for the longest period and • has the lowest operational risk profile when implemented, has a higher inherent value than engineering that does not follow such principles when all other factors remain the same. We conclude that infrastructure renewal guided by the principles of standardisation, obsolescence reduction and operational risk mitigation has a higher value than that without such guidance. We also demonstrate evidence of synergy between the three guiding principles through some examples. [ABSTRACT FROM AUTHOR]

For practical engineering purpose, a new flat shell element baptized (ACM_Q4SBE1) is presented in this paper. The formulated element can be used for the analysis of thin shell structures; no matter how the geometrical shape might be. Tests on standard problems have been examined. Since, the analysis of thin shell structures has generally been purely carried out on a theoretical basis; it is of importance to present some experimental results of an elliptical paraboloid under uniformly distributed load pressure. The results obtained from both numerical and experimental work are presented. [ABSTRACT FROM AUTHOR]

This paper provides estimation of reliability of a component subjected to life testing and the procedure includes essentially polling of two samples of failure data, where the component follows exponential failure model. We assumed that some prior information is available in the form of an initial guess value (θ0) about the value of the parameter (θ) of exponential distribution from the past, and proposed a two stage shrinkage pooling estimator (TSPE) of reliability function of exponential distribution using complete failure data. The expressions for the bias, mean squared error, expected sample size and relative efficiency are derived. Conclusions regarding the constants involved in the proposed estimator are presented. Simulation, comparisons, and numerical results are reported. The proposed estimator fairs better than the classical two stage pooling estimator. [ABSTRACT FROM AUTHOR]

In order to obtain a suitable rigid implant, we need to be certain that its properties are very close to the structure it is supposed to replace or support. For this reason, the materials to be used for manufacturing should be carefully selected, so that their mechanical and biomechanical properties correspond to the intended purpose. The present paper is dealing with some impact tests developed for these types of structures and the required testing methodology. [ABSTRACT FROM AUTHOR]

In this paper, a new elastic-wave-based NDT system was proposed and then applied to reveal the defects inside the concrete specimens by imaging method. In this NDT system, it integrates the point-source/point-receiver scheme with the synthetic aperture focusing technique (SAFT) to achieve the effect like scanning with a phase array system; hence it is equipped with large functioning depth because of the high-energy feature that transient elastic wave method possessed over traditional ultrasonic method. This system is mainly composed of an impact source generator, a vertical displacement transducer, a signal capturing unit and operation software. To evaluate the feasibility of this system on NDT of concrete structures, some concrete slabs with artificial voids inside were built for experiment. 2D plane stress FEM numerical simulations were performed for further comparison. Experimental result shows good agreement with the numerical result not only on the B-scan diagram but also on the processed scanning image. The elastic-wave-based scanning system proposed in this paper exhibits high potential in inspecting the defects of in-situ concrete structures by imaging for civil engineering applications. [ABSTRACT FROM AUTHOR]

TOKAI RIKA is a manufacturer using 3D data in their operations. The company's core business lies in the production of car parts. To enhance their in-house mold-making operations, the company decided to switch from paper to 3D data. The company proved very successful by using a unique method of coloring work specifications. They are using 3D to improve engineering communication in mold design. [ABSTRACT FROM AUTHOR]

Due to the difficulty of handling both hysteresis and interactions between subsystems, there are limited results available on decentralized stabilization of unknown interconnected systems with hysteresis, even though the problem is practical and important. In this chapter, we provide solutions to this challenging problem by proposing two new schemes to design decentralized output feedback adaptive controllers using backstepping approach. For each subsystem, a general transfer function with arbitrary relative degree is considered. The interactions between subsystems are allowed to satisfy a nonlinear bound with certain structural conditions. In the first scheme, no knowledge is assumed on the bounds of unknown system parameters. In case that the uncertain parameters are inside known compact sets, we propose an alternative scheme where a projection operation is employed in the adaptive laws. In both schemes, the effect of the hysteresis and the effects due to interactions are taken into consideration in devising local control laws. It is shown that the designed local adaptive controllers can ensure all the signals in the closed loop system bounded. A root mean square type of bound is obtained for the system states as a function of design parameters. This implies that the transient system performance can be adjusted by choosing suitable design parameters. With Scheme II, the proposed control laws allow arbitrarily strong interactions provided their upper bounds are available. In the absence of hysteresis, perfect stabilization is ensured and the L2 norm of the system states is also shown to be bounded by a function of design parameters when the second scheme is applied. [ABSTRACT FROM AUTHOR]

The general thermodynamically based theory of the constitutive and evolution equations of elastic-brittle damaged materials in a total stress-strain formulation, developed by Murakami and Kamiya [162], is the key for a further extension presented in the paper by Kuna-Ciska l and Skrzypek [208]. The Helmholtz free energy is a function of the elastic strain tensor εe, the second-rank damage tensor D, and another scalar damage variable β. The following Helmholtz free energy decomposition into the elastic and the damage terms is postulated as the state potential (2.20): 3.1$$ \rho \Psi (\varepsilon ^e ,D,\beta ) = \rho \Psi ^e (\varepsilon ^e ,D) + \rho \Psi ^d (\beta ) $$ [ABSTRACT FROM AUTHOR]

An enormous amount of multimedia data will be transmitted by various devices in the wireless personal area network, and this network environment will require very high transmission capacity. In this paper, we apply multiple antennas to MB-OFDM UWB system for high performance. With an emphasis on a preamble design for multichannel separation, we address the channel estimation in MB-OFDM system with multiple antennas. By properly designing each preamble for multiple antennas to be orthogonal in the time domain, the channel estimation can be applied to the MB-OFDM proposal for IEEE 802.15.3a standard in the case of more than two transmit antennas. By using the multiantenna scheme and proposed channel estimation technique, the reliability and performance of the MB-OFDM system can be improved. [ABSTRACT FROM AUTHOR]

A combination of OFDM with FDMA (called OFDMA) is regarded as a promising solution for improving the performance of BWA with multiple users. Although transmit diversity is clearly advantageous in OFDMA systems, it may not be possible that practical OFDMA systems have more than two antennas due to size, cost, or hardware limitations. Cooperative networks aim to utilize the available terminals as a collection of distributed antennas for the transmission of signals from one end of the network to the other. This paper focuses on design and performance evaluation of IEEE 802.16 MIMO-OFDMA systems with cooperative diversity. In this chapter, for high-rate and reliable transmission, efficient transmission codes of cooperative transmission are proposed for each transmission case (single transmission case or mutual transmission case). [ABSTRACT FROM AUTHOR]

Radio frequency identification (RFID) technology is not fundamentally new and concerns a whole range of applications. The first RFID application may have been the Royal British Air Force's "Identify Friend or Foe" system, which was used during the Second World War to identify friendly aircraft. RFID can be applied to a variety of tasks, structures, work systems, and contexts along the value chain, including business-to-business (B-2-B) logistics, internal operations, business-toconsumer (B-2-C) marketing, and after-sales service applications [1-6]. However, the boom that RFID technology enjoys today is basically due to the standardization [7] and development of low cost devices. Like every wireless device, RFID systems bring with them security and privacy issues to all those people who have been working in this area. Security issues involve classic attacks, namely denial of service, impersonation of tags, or channel eavesdropping. These attacks are rendered more practicable because of the tags' lack of computational and storage capacity. There are many papers investigating these issues in various ways [7, 8, 10-12, 14]. Today's challenge is to find protocols (or deployments) which allow authorized parties to identify the tags without an adversary being able to track them, thus getting to the root of the privacy problem [8, 13]. It is well known that the reason not to use well known authentication protocols is that such protocols do not preserve the privacy of the provider. Asymmetric cryptography could easily solve this problem, but it is too heavy to be implemented within a tag. [ABSTRACT FROM AUTHOR]

Searching information on the Web can be viewed as extremely easy, or it can be extremely difficult. This is because the WWW is not indexed like many library catalogs or journal-article indexes. When we search on the Web, we are not searching it directly but are actually searching the Web pages collected and indexed by a search tool from computers all over the world that contains the actual Web pages. Examples of search tools are Yahoo! Search, Google, Alta Vista, and so on. The different types of search tools have their own strengths and weaknesses. Depending on your information needs, one may work better for you than another. Search directories are hierarchical databases with references to websites. The websites that are included are classified according to the rules of that particular search service. Search engines, on the other hand, use software to crawl the Internet in search of what you would like using of terms or keywords. Specialized databases are the hidden parts of the WWW that are normally not found by regular search engines [1]. This paper presents the extension work from Integrated Filtered Web-Search Engine (IFWSE) [2] by looking at the enhancement of the program structure to retrieve the search hits. Further experiments were also carried out to compare its performance with with a well-established, meta-search engine-the MetaCrawler [3] [4]. [ABSTRACT FROM AUTHOR]

The contributions, lessons, and trends found in the DESider Symposium Proceedings are discussed. Three broad classifications can be made among the papers: The first is between studies which widen the code- and user-base of DES and its range of applications to establish the current level of quality, and those which bring out neighbouring hybrid concepts such as SAS for discussions and improvements.The second is between "natural" uses of DES with boundary layers fully covered by RANS, and uses with RANS only as a wall model in LES.The third is between single-model methods such as DES, and zonal methods even if they are closely related. [ABSTRACT FROM AUTHOR]

Hybrid RANS/LES methods combine the advantages of RANS models in terms of simulation costs, with the ability of LES to capture unsteady flow structures. A problem encountered in applications of this technique is the transmission of information between the RANS and LES zones: in the RANS region only mean-flow data is available, and the Reynolds shear stresses are entirely supported by the turbulence model; in the LES region, on the other hand, turbulent eddies must be present to support the turbulent momentum transport. The generation of these eddies is a critical ingredient in determining the effectiveness and accuracy of a hybrid method. In this paper we discuss this problem for applications in which the RANS region is below the LES zone, and in cases in which the flow advects from RANS to LES regions. We will also present recent results from our research group. [ABSTRACT FROM AUTHOR]

The paper evaluates a new method for prescribing synthesized turbulent inlet boundary conditions. When making LES, DES or hybrid LES-RANS, a precursor channel DNS is often used. The disadvantage of this method is that it is difficult to re-scale the DNS fluctuations to higher Reynolds numbers. In the present work, synthesized isotropic turbulent fluctuations are generated at the inlet plane with a prescribed turbulent length scale and energy spectrum. A large number of independent realizations are generated. A correlation in time between these realizations is introduced via an asymmetric, non-truncated time filter. In this way the turbulent time scale of the synthesized isotropic turbulent fluctuations is prescribed. [ABSTRACT FROM AUTHOR]

This paper is devoted to the study of the behaviour of DES-type methods used as Wall-Modelled-Large-Eddy-Simulation (WMLES) and to the treatment of the eddy viscosity in the framework of turbulent inlet conditions. A new method named Stimulated Detached Eddy Simulation (SDES) based on a synthetic turbulence method including pseudo-eddy viscosity synthetization is proposed and assessed on a spatially developing boundary layer. [ABSTRACT FROM AUTHOR]

The present paper summarizes the research conducted at the University of Manchester over the course of the Desider project on methods of generation of synthetic turbulence. A random procedure, referred to as the Synthetic Eddy Method (SEM), based on the classical view of turbulence as a superposition of coherent structures was developed and compared with other methods of generation of inflow boundary conditions for LES, for different types of wall bounded flows. Synthetic inflow generation methods always show a transition region downstream of the inlet until the turbulence recovers an equilibrium state. The sensitivity of this transition region to variations in the synthetic inflow turbulence energy, length scale and time scale is studied herein with applications to hybrid RANS-LES methods in mind, as RANS results cannot be expected to provide accurate values for these scales to the LES region. A parameterization of the SEM suitable for hybrid RANS-LES simulations is proposed and tested on hybrid RANS-LES simulations of several wall bounded flows, with an emphasis on the flat plat boundary layer. [ABSTRACT FROM AUTHOR]

This paper focuses on numerical aspects for hybrid RANS-LES computations using the X-LES method. In particular, the impact of using a high-order finite-volume scheme is considered. The finite-volume scheme is fourth-order accurate on non-uniform, curvilinear grids, has low numerical dispersion and dissipation, and is based on the skew-symmetric form of the compressible convection operator, which ensures that kinetic energy is conserved by convection. A limited grid convergence study is performed for the flow over a rounded bump in a square duct. The fourth-order results are shown to depend only mildly on the grid resolution. In contrast, second-order results require at least half the mesh size to become comparable to the fourth-order results. Additionally, the high-order method is extended with shock-capturing capability in such a way that interference with the subgrid-scale model is avoided. The suitability of this extension is demonstrated by means of a supersonic flow over a cavity. [ABSTRACT FROM AUTHOR]

This paper presents a first industrial attempt at Eurocopter Germany to use DES-like methods to compute the wake behind a helicopter in forward flight. Three codes have been used: TAU (DLR), CFX (Ansys) and HMB (Uni. Liverpool) and four different turbulence models: standard SST and three of its unsteady extensions SAS, DES and XLES. Results for the loads, pressure distribution and skin-friction lines have been compared to each other and against wind tunnel experimental data. These more sophisticated models brought improvements over the base SST but not always markedly and consistently: the drag gets improved although the negative lift on the body departs further form the experimental value. The pressure distribution on the backdoor has been improved by one of the computation. Oil-flow visualisation results show that the mean flow in the region of the backdoor is qualitatively reasonably well captured. [ABSTRACT FROM AUTHOR]

In this paper the three-dimensional non-reacting turbulent flow field of a swirl-stabilized gas turbine model combustor is analysed with compressible CFD. For the flow analysis URANS and Hybrid RANS/LES (DES, SAS) turbulence models were applied. The governing equations and the numerical method are described. The simulations were performed using the commercial CFD software package ANSYS CFX-10.0. The numerically achieved velocity components show a good agreement with the experimental values obtained by Particle Image Velocimetry (PIV). Furthermore, a precessing vortex core (PVC) could be found in the combustion chamber. [ABSTRACT FROM AUTHOR]