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.

Oh Britannia: Great Britain’s Exit from the European Union and Its Impact on Globalism and Nationalism

2021 ◽  
Vol 20 (1-2) ◽  
pp. 186-202
Author(s):  
John P. Williams
Keyword(s):  
European Union ◽  
Banking System ◽  
Free Movement ◽  
The European Union ◽  
System A ◽  
Nation States ◽  
The Future ◽  
Left And Right ◽  
Free Movement Of Capital ◽  
The Eu

Abstract Globalization unleashed trends such as the free movement of capital, people, and goods; trickle-down economics, and diminished stature of nation-states. While largely embraced by most countries in the WTO, a growing tension within the European Union to push back went largely ignored until recently. Britain’s exit represents such a push back, a rejection of a single banking system, a single budget, and a single political entity. This article examines the historic 2016 British referendum that saw 52 percent of voters favor England leaving the EU. This research serves four purposes: one, to identify the origins of this important referendum as well as the positions of both its supporters and detractors; two, to analyze the fallout of the vote and its impact on other European nations; three, to correlate the results of this referendum and the rise of populist parties on the left and right in the EU; and four, to discuss briefly what the future holds for globalism.

THE EU SUGAR MARKET PROFILE AND ITS MAIN DRIVERS

2015 ◽  
Author(s):  
Lubos SMUTKA ◽  
Irena BENEŠOVÁ ◽  
Patrik ROVNÝ ◽  
Renata MATYSIK-PEJAS
Keyword(s):  
Market Failure ◽  
Current System ◽  
Quota System ◽  
Considerable Debate ◽  
Sugar Market ◽  
The Common ◽  
The One ◽  
Production Capacities ◽  
The Given ◽  
The Eu

Sugar is one of the most important elements in human nutrition. The Common Market Organisation for sugar has been a subject of considerable debate since its establishment in 1968. The European agricultural market has been criticized for its heavy regulations and subsidization. The sugar market is one of the most regulated ones; however, this will change radically in 2017 when the current system of production quotas will end. The current EU sugar market changed is structure during the last several decades. The significant number of companies left the market and EU internal sugar market became more concentrated. The aim of this paper is presentation characteristics of sugar market with respect to the supposed market failure – reduction in competition. The analysis also identifies the main drivers and determinants of the EU especially quota sugar market. In relation to paper’s aim the following results are important. The present conditions of the European sugar market have led to market failure when nearly 75 % (10 million tonnes) of the quota is controlled by five multinational companies only. These multinational alliances (especially German and French one) are also taking control over the production capacities of their subsidiaries. In most countries, this causes serious problems as the given quota is controlled by one or two producers only. This is a significant indicator of market imperfection. The quota system cannot overcome the problem of production quotas on the one hand and the demand on the other; furthermore, it also leads to economic inefficiency. The current EU sugar market is under the control of only Sudzucker, Nordzucker, Pfeifer and Langen, Tereos and ABF.

Conference Reports

2005 ◽  
Vol 55 (2) ◽  
pp. 223-234
Author(s):  
Edin Mujagic ◽  
Dóra Győrffy ◽  
László Jankovics
Keyword(s):  
Economic Policy ◽  
European Association ◽  
Policy Research ◽  
Conference Report ◽  
Annual Conference ◽  
Summer Institute ◽  
The West ◽  
The Future ◽  
Economic Studies ◽  
The Eu

EMU Enlargement to the East and the West CEPR/ESI Conference. Report of the 8th annual conference of the Centre for Economic Policy Research (CEPR) and the European Summer Institute (ESI) held in September 2004 in Budapest, Hungary. (Conference report by Edin Mujagic); Dilemmas around the future enlargement of the EU-EACES Conference. The European Association for Comparative Economic Studies (EACES) held its 8th biannual conference at the Faculty of Economics in Belgrade on September 23-25, 2004. (Conference report by Dóra Gyõrffy and László Jankovics)

scholarly journals On Western strategy towards Russia: From ‘Putin first’ to ‘democracy first’

European View ◽  
2021 ◽  
pp. 178168582110033
Author(s):  
Andrius Kubilius
Keyword(s):  
Russian Society ◽  
The West ◽  
Strategic Approach ◽  
Democratic Change ◽  
The Future ◽  
A Priority ◽  
Vladimir Putin ◽  
The Eu

The article analyses two distinct approaches that Western leaders have taken to relations with Putin’s Russia. It argues that the dominant approach of fostering good relations with Vladimir Putin, prioritising these over support for longer-term democratic change in Russia, has not brought any results and is damaging the interests of Russian society, neighbouring countries and the West. The article analyses the prerequisites for deep change in Russia and argues that there is a need for the EU to comprehensively review and change its strategy towards Russia, putting democracy at its core. It discusses in detail the deterrence, containment and transformation elements of a new EU strategy. The article emphasises that the strategic approach of ‘democracy first’ in relations with Russia also relates to the future of democracy in general and should be a priority of EU–US cooperation.

scholarly journals The EU Elephant: Europe in the 2021 Dutch General Elections

2021 ◽  
Vol 56 (2) ◽  
pp. 70-75
Author(s):  
Simon Otjes
Keyword(s):  
The Netherlands ◽  
The Future ◽  
General Elections ◽  
The Eu

AbstractFor the Netherlands, the single most important EU issue is the future of the eurozone.

Sinai and Exodus: Two Grounds for Hope in the Jewish Tradition

1978 ◽  
Vol 14 (3) ◽  
pp. 373-387
Author(s):  
David Hartman
Keyword(s):  
Jewish Tradition ◽  
Look Ahead ◽  
The World ◽  
The Future ◽  
Sole Criterion ◽  
The Given ◽  
Better Than

Hope is a category of transcedence, by means of which a man does not permit what he senses and experiences to be the sole criterion of what is possible. It is the belief or the conviction that present reality (what I see) does not exhaust the potentialities of the given data. Hope opens the present to the future; it enables a man to look ahead, to break the fixity of what he observes, and to perceive the world as open-textured. The categories of possibility and of transcendence interweave a closely stitched fabric - hope says that tomorrow can be better than today.

scholarly journals The Accession Pedagogy

2014 ◽  
Vol 23 (1) ◽  
pp. 99-120 ◽  
Author(s):  
Bilge Firat
Keyword(s):  
European Integration ◽  
Policy Tools ◽  
Government Officials ◽  
The Future ◽  
Past Experiences ◽  
Tools And Techniques ◽  
Viable Model ◽  
The Eu

From 1989, new plans to enlarge the EU caused growing public disenchantment with the future of European integration as a viable model of cooperation among states and peoples in Europe. To manage disenchantment, EU actors designed various policy tools and techniques in their approaches to European peripheries such as Turkey. Among these, they intensified and perfected processes of pedagogy where EU actors assume that they have unique knowledge of what it means to be 'European' and that they must teach accession candidates how to become true Europeans. Based on accounts of EU politicians and officials, past experiences of government officials from former EU candidate states and Turkish officials' encounters with the EU's accession pedagogy, this article explores the EU's enlargement policy as a pedagogical engagement and the responses it elicits among Turkish governmental representatives, in order to test the reconfigurations of power between Europe and the countries on its margins.

An Overview of the Recommender System

2013 ◽  
Vol 302 ◽  
pp. 787-791
Author(s):  
Lu Zhao ◽  
Rong Rong Yang ◽  
Meng Zhai ◽  
Feng Ming Liu
Keyword(s):  
Recommender System ◽  
System A ◽  
The Future

Delivering recommendation services are the trend of the future, so Recommender System varied very vital and widely applied in e-commerce websites to help customers in finding the items they want. A recommender system should be able to provide users with useful information about the items that might be interesting to them. The ability of immediately responding to changes in users preferences is a valuable asset for such systems. In recommender system, a variety of methods have been emerged as the basis for recommender. However, existing recommendation methods have the limitation. To overcome this limitation, we will propose new recommender system by combining the existing techniques. So, we firstly give an overview of recommender system for the future researches.

The influence of the trailing edge angle of the micro centrifugal impeller on the performance of the centrifugal compressor

2021 ◽  
pp. 1-15
Author(s):  
Xu Yu-dong ◽  
Li Cong ◽  
Lv Qiong-ying ◽  
Zhang Xin-ming ◽  
Mu Guo-zhen
Keyword(s):  
Centrifugal Compressor ◽  
Pressure Ratio ◽  
Centrifugal Impeller ◽  
Centrifugal Compressors ◽  
Trailing Edge ◽  
Sweep Angle ◽  
Impeller Blade ◽  
Bending Angle ◽  
Edge Angle ◽  
Isentropic Efficiency

In order to study the effect of the trailing edge sweep angle of the centrifugal impeller on the aerodynamic performance of the centrifugal compressor, 6 groups of centrifugal impellers with different bending angles and 5 groups of different inclination angles were designed to achieve different impeller blade trailing edge angle. The computational fluid dynamics (CFD) method was used to simulate and analyze the flow field of centrifugal compressors with different blade shapes under design conditions. The research results show that for transonic micro centrifugal compressors, changing the blade trailing edge sweep angle can improve the compressor’s isentropic efficiency and pressure ratio. The pressure ratio of the compressor shows a trend of increasing first and then decreasing with the increase of the blade bending angle. When the blade bending angle is 45°, the pressure ratio of the centrifugal compressor reaches a maximum of 1.69, and the isentropic efficiency is 67.3%. But changing the inclination angle of the blade trailing edge has little effect on the isentropic efficiency and pressure ratio. The sweep angle of blade trailing edge is an effective method to improve its isentropic efficiency and pressure ratio. This analysis method provides a reference for the rational selection of the blade trailing edge angle, and provides a reference for the design of micro centrifugal compressors under high Reynolds numbers.

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