scholarly journals DLR TAU-Code uRANS Turbofan Modeling for Aircraft Aerodynamics Investigations

Aerospace ◽  
2019 ◽  
Vol 6 (11) ◽  
pp. 121 ◽  
Author(s):  
Arne Stuermer
Keyword(s):  
Best Practice ◽  
Fuel Efficiency ◽  
Careful Consideration ◽  
Cfd Simulations ◽  
Engine Modeling ◽  
Depth Study ◽  
Unsteady Rans ◽  
Aircraft Aerodynamics ◽  
Bypass Ratio ◽  
The Eu

In the context of an increased focus on fuel efficiency and environmental impact, turbofan engine developments continue towards larger bypass ratio engine designs, with Ultra-High Bypass Ratio (UHBR) engines becoming a likely power plant option for future commercial transport aircraft. These engines promise low specific fuel consumption at the engine level, but the resulting size of the nacelle poses challenges in terms of the installation on the airframe. Thus, their integration on an aircraft requires careful consideration of complex engine–airframe interactions impacting performance, aeroelastics and aeroacoustics on both the airframe and the engine sides. As a partner in the EU funded Clean Sky 2 project ASPIRE, the DLR Institute of Aerodynamics and Flow Technology is contributing to an investigation of numerical analysis approaches, which draws on a generic representative UHBR engine configuration specifically designed in the frame of the project. In the present paper, project results are discussed, which aimed at demonstrating the suitability and accuracy of an unsteady RANS-based engine modeling approach in the context of external aerodynamics focused CFD simulations with the DLR TAU-Code. For this high-fidelity approach with a geometrically fully modeled fan stage, an in-depth study on spatial and temporal resolution requirements was performed, and the results were compared with simpler methods using classical engine boundary conditions. The primary aim is to identify the capabilities and shortcomings of these modeling approaches, and to develop a best-practice for the uRANS simulations as well as determine the best application scenarios.

The crisis of multilateralism and EU–Russia cooperation

2020 ◽  
Vol 22 (1) ◽  
pp. 54-57
Author(s):  
FRANCO BRUNI ◽  
Keyword(s):  
International Relations ◽  
Careful Consideration ◽  
Modern World ◽  
Multiple Methods ◽  
The Us ◽  
Good For ◽  
East West ◽  
The Eu

The article is devoted to problems in relations between the EU and Russia. Multiple methods are considered that are aimed at solving the problem of multilateralism in current conditions. The author selected and studied specific documents on essential aspects that are devoted to this topic. Studying the arising problems requires careful consideration since, in the modern world, cooperation between global actors such as the EU and Russia cannot be ignored. Despite all the challenges faced by the parties in their fields, all difficulties are conquerable, and the article provides specific methods for its solving. The article discusses some aspects and problems that require particular attention from specialists in this field. The author concludes that strong US–EU coalition could seem more coherent with history and with the traditional East–West divide. However, the recent evolution of the US attitude towards international relations weakens the probability of such coalition and its perceived payoffs. A more or less defensive Russia–China coalition has been tried with limited results; moreover, if it were possible and probable, the two western players would change their strategy to prevent it or to contain its depth. In fact, we live in a world where many talks of a serious possibility of G2 governance, a peculiar type of coalition where the US and China keep hostile and nationalistic attitudes but join forces to set the global stage in their favor, pursuing a qualitatively limited but quantitatively rich payoff. In such world, as a counterpart of this payoff, both the divided Europe and the economically much smaller Russia would lose power and suffer several kinds of economic disadvantages. Therefore, Greater Europe would be good for Russia and for the EU as well.

scholarly journals CFD Study of Nozzle Configurations for Ultra High Bypass Engines

1993 ◽  
Author(s):  
H. Zimmermann ◽  
R. Gumucio ◽  
K. Katheder ◽  
A. Jula
Keyword(s):  
Engine Performance ◽  
Operating Conditions ◽  
Aerodynamic Design ◽  
Thrust Coefficient ◽  
Optimum Range ◽  
Installation Effects ◽  
Wide Range ◽  
And Performance ◽  
Aircraft Aerodynamics ◽  
Bypass Ratio

Performance and aerodynamic aspects of ultra-high bypass ratio ducted engines have been investigated with an emphasis on nozzle aerodynamics. The interference with aircraft aerodynamics could not be covered. Numerical methods were used for aerodynamic investigations of geometrically different aft end configurations for bypass ratios between 12 and 18, this is the optimum range for long missions which will be important for future civil engine applications. Results are presented for a wide range of operating conditions and effects on engine performance are discussed. The limitations for higher bypass ratios than 12 to 18 do not come from nozzle aerodynamics but from installation effects. It is shown that using CFD and performance calculations an improved aerodynamic design can be achieved. Based on existing correlations, for thrust and mass-flow, or using aerodynamic tailoring by CFD and including performance investigations, it is possible to increase the thrust coefficient up to 1%.

14. Policy-making in the European Union

2016 ◽  
Author(s):  
Ralf Drachenberg ◽  
Alex Brianson
Keyword(s):  
European Union ◽  
Policy Making ◽  
Best Practice ◽  
The European Union ◽  
New Governance ◽  
Policy Decisions ◽  
State Action ◽  
Eu Policy ◽  
Governance Tools ◽  
The Eu

This chapter examines the process of policy-making in the European Union. It first considers how the EU originally made policy decisions before tracing the evolution of the formal balance between the EU institutions over time, with particular emphasis on the increasing legislative power of the European Parliament. It then describes the Community method, which remains the core of the EU policy process but is now complemented with a range of ‘new governance tools’ designed to produce coordinated member state action through iterated processes of standard-setting, best practice identification, and knowledge transfer. One of these processes is the open method of coordination (OMC). The chapter concludes with an analysis of the implementation of EU policy decisions by and in the member states, along with current trends in EU decision-making after the EU enlargements of the 2000s and the ratification of the Lisbon Treaty.

The EU ECENTRE Project

2013 ◽  
Vol 3 (4) ◽  
pp. 10-21
Author(s):  
Denis Edgar-Nevill
Keyword(s):  
European Commission ◽  
Best Practice ◽  
Complex Problem ◽  
Cyber Terrorism ◽  
Internet Crime ◽  
Significant Research ◽  
Considerable Problem ◽  
Funded Project ◽  
Research And Education ◽  
The Eu

Since the EU Cybercrime Convention in 2000 (EU 2001), there has been a clear recognition of the accelerating threats to society posed by those who would exploit computers for crime and the logical progression to cyber-terrorism and cyberwarfare. Since that time the capacity to deal with cybercrime (crimes involving the use of computers) has improved but the problem has grown alarmingly. The European Commission recognises the increasing threat of cybercrime and has committed significant research and development funding in seeking to protect the community from cybercrime and cyberwar. This paper discusses a new European Commission funded project ECENTRE – England's Cybercrime Centre of Excellence Network for Training, Research and Education. On 20th December 2012 the European Commission signed the €0.935million (£760,000) contract for the project. The contract is awarded under the Programme Prevention of and Fight against Internet Crime Targeted Call – ISEC 2011 Action Grants– Project Number HOME/2011/ISEC/AG/INT/4000002226. The author is the Project Manager and Principal Investigator for the project. ECENTRE forms part of a wider European network of centres of excellence to share expertise, promote best practice and provide training opportunities for law enforcement across the EU. The challenges in establishing effecting cooperation and sharing are discussed. The considerable problem of keeping pace with the fast-developing, complex, problem posed by threats to national infrastructure, organisations and individuals is examined; highlighting the role of education as a fundamental weapon in the fight. The more we know about a threat (real or potential) – the better protected against it we become.

scholarly journals Regionální nástroje na podporu výzkumu, vývoje a inovací – porovnání situace v Česku s příklady dobré praxe ze zemí EU / Regional measures supporting research, development and innovation – comparison of the situation in Czechia with best practices in the EU countries

Ergo ◽  
2015 ◽  
Vol 10 (4) ◽  
pp. 13-20
Author(s):  
Miroslav Kostić
Keyword(s):  
Best Practices ◽  
Best Practice ◽  
Knowledge Flows ◽  
Research Development ◽  
Regional Innovation ◽  
Eu Countries ◽  
Research And Innovation ◽  
Support Measures ◽  
Excellent Research ◽  
The Eu

The article describes the types of regional measures supporting research, development and innovation in Czechia in the context of the typology of regional support measures in the EU countries, based on the Regional Innovation Monitor Plus project. It also presents best practices from European regions, selected according to positive experience with application of the measures at the regional level and the results achieved. In terms of realisation of own research and innovation strategies, Czech regions are limited by strong dependency on support measures implemented from national and European level. Nevertheless, this dependency is typical also for regions in the remaining new member states. Another problem is the low level of cooperation between academic and business sector - in terms of both financial and knowledge flows. This does not allow to fully utilise the potential of territorial proximity within the regions, where innovative companies and excellent research teams can be often found side by side. Appropriate and well-considered application of foreign best practice measures and models (or their elements) of research & innovation support can help to mitigate problems of a concrete region. Furthermore, it has relevance for the development of strategic approaches to regional policy which consider possible cuts in European funding in a long-term horizon.

School Counselor Advocacy: When Law and Ethics May Collide

2010 ◽  
Vol 13 (4) ◽  
pp. 2156759X1001300
Author(s):  
Carolyn B. Stone ◽  
Perry A. Zirkel
Keyword(s):  
School Counselors ◽  
School Counselor ◽  
Best Practice ◽  
Careful Consideration ◽  
Ethical Principles ◽  
Ethical Conflict ◽  
Legal Requirements ◽  
Legal Rules ◽  
Ethical Codes ◽  
Law And Ethics

Legal rules establish basic duties akin to the floor for acceptable behavior, whereas ethical codes represent aspirational standards for best practice. For school counselors, fulfilling both legal requirements and ethical principles may pose challenges that warrant careful consideration. This article outlines a legal/ethical conflict in the case of Woodlock v. Orange Ulster B.O.C.E.S. (2006/2008), in which the school counselor followed the ethical precept of advocacy but did so in a way that collided with legal protections.

Numerical Investigations on the Conceptual Design of a Ducted Contra-Rotating Fan

2014 ◽  
Author(s):  
Chao Huo ◽  
Nestor Gonzalez Diez ◽  
Arvind Gangoli Rao
Keyword(s):  
Pressure Ratio ◽  
Advisory Council ◽  
Cfd Simulations ◽  
System A ◽  
The Future ◽  
Design Requirements ◽  
The Given ◽  
Isentropic Efficiency ◽  
Crf System ◽  
The Eu

The Advisory Council for Aeronautics Research in Europe (ACARE) has set an ambitious array of objectives to be accomplished by 2050. It is often claimed that complying with those targets will not require evolution but, rather, revolution. If the growth in aviation has to be sustained in the future then we must come up with radical aircraft and engine configurations which can meet the demands of future aviation. The contra-rotating fan is one such system which can play an important role in the future engine configurations, such as the hybrid engine configuration that is being investigated in the EU cofounded AHEAD project. In order to design a CRF system, a 1-D code has been developed based on the inverse Blade Element Method (BEM) to design a contra rotating fan. The CRF design obtained from this methodology is then analyzed with a full 3D RANS simulation. The numerical analysis revealed that the performance of the first rotor satisfies with the given design requirements in terms of both pressure ratio and isentropic efficiency, thus proving the efficacy of using the 1-D code for designing the CRF. However, the performance of the rear rotor does not reach the design demands. It was observed that there is a strong flow separation around the root and a strong normal shock in the blade passage near the tip. It was found that there is a great difference between the blade metal inlet angles and the relative flow inlet angles near the root of the rear rotor. One of the main reasons for this is the calculation of the axial velocity depending on the vortex design and the resolution of the radial equilibrium. Based on the CFD simulations, the design code could be further modified to improve the design of CRF.

scholarly journals The Past and Present of Discharge Capacity Modeling for Spillways—A Swedish Perspective

Fluids ◽  
2019 ◽  
Vol 4 (1) ◽  
pp. 10 ◽  
Author(s):  
James Yang ◽  
Patrik Andreasson ◽  
Penghua Teng ◽  
Qiancheng Xie
Keyword(s):  
Discharge Capacity ◽  
Best Practice ◽  
Primary Source ◽  
Hydraulic Modeling ◽  
Model Tests ◽  
Laboratory Model ◽  
Model Quality ◽  
Cfd Simulations ◽  
Discharge Data ◽  
The Past

Most of the hydropower dams in Sweden were built before 1980. The present dam-safety guidelines have resulted in higher design floods than their spillway discharge capacity and the need for structural upgrades. This has led to renewed laboratory model tests. For some dams, even computational fluid dynamics (CFD) simulations are performed. This provides the possibility to compare the spillway discharge data between the model tests performed a few decades apart. The paper presents the hydropower development, the needs for the ongoing dam rehabilitations and the history of physical hydraulic modeling in Sweden. More than 20 spillways, both surface and bottom types, are analyzed to evaluate their discharge modeling accuracy. The past and present model tests are compared with each other and with the CFD results if available. Discrepancies do exist in the discharges between the model tests made a few decades apart. The differences fall within the range −8.3%–+11.2%. The reasons for the discrepancies are sought from several aspects. The primary source of the errors is seemingly the model construction quality and flow measurement method. The machine milling technique and 3D printing reduce the source of construction errors and improve the model quality. Results of the CFD simulations differ, at the maximum, by 3.8% from the physical tests. They are conducted without knowledge of the physical model results in advance. Following the best practice guidelines, CFD should generate results of decent accuracy for discharge prediction.

scholarly journals AMMISSIONE DI STRANIERI SUL TERRITORIO NAZIONALE ATTRAVERSO ‘CORRIDOI UMANITARI’ CON SPONSOR PRIVATI

2020 ◽  
Author(s):  
Carola Ricci
Keyword(s):  
New York ◽  
International Law ◽  
Best Practice ◽  
Humanitarian Assistance ◽  
Legal Basis ◽  
Safe Alternative ◽  
Security Screening ◽  
Challenges And Opportunities ◽  
Multi Stakeholder ◽  
The Eu

The scope of the present research is to understand to what extent a recent and fruitful private initiative sponsoring a safe alternative legal pathway ‘par avion’ recently spread from Italy and called “humanitarian corridors”, may in a future become a general and uniform alternative model for other European Union States. Such a best practice, which represents currently an exceptional route for vulnerable migrants mostly from Lebanon and Eritrea to enter the country without harm after a security screening and to be materially supported by the same sponsors in the crucial initial phase of integration, could potentially be extended to other EU States. Its legal basis should not be restricted to Article 25 of the Visa Code (recently interpreted by the EU Court of Justice as posing no obligation on Member States to grant humanitarian visa). There already exist clear obligations to grant humanitarian assistance to vulnerable people at risk stemming out from international law (both general and conventional) that do constitute the adequate legal basis both for States and civil society, to act in a “multi-stakeholder alliance” in order to find solutions to the challenges and opportunities deriving from international migration, as indicated in the 2016 New York Declaration.

On the importance of adjusting for distorting factors in benchmarking analysis, as illustrated by a cost comparison of the different forms of implementation of the EU Packaging Directive

2017 ◽  
Vol 35 (12) ◽  
pp. 1266-1277 ◽  
Author(s):  
Heinz-Georg Baum ◽  
Dieter Schuch
Keyword(s):  
Cost Efficiency ◽  
Best Practice ◽  
National Level ◽  
Cost Comparison ◽  
Extended Producer Responsibility ◽  
Benchmark Study ◽  
Producer Responsibility ◽  
Directorate General ◽  
The Cost ◽  
The Eu

Benchmarking is a proven and widely used business tool for identifying best practice. To produce robust results, the objects of comparison used in benchmarking analysis need to be structurally comparable and distorting factors need to be eliminated. We focus on a specific example – a benchmark study commissioned by the European Commission’s Directorate-General for Environment on the implementation of Extended Producer Responsibility (EPR) for packaging at the national level – to discuss potential distorting factors and take them into account in the calculation. The cost of compliance per inhabitant and year, which is used as the key cost efficiency indicator in the study, is adjusted to take account of seven factors. The results clearly show that differences in performance may play a role, but the (legal) implementation of EPR – which is highly heterogeneous across countries – is the single most important cost determinant and must be taken into account to avoid misinterpretation and false conclusions.

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