Multi-physical modelling and analysis of lubricated transmissions using a coupled finite element approach

Lubrication is vital to improve performance, efficiency and durability in transmissions; it serves to minimize wear, noise, vibration and friction. The proper functioning of lubricated transmissions relies on interactions amongst a wide range of physical phenomena (contact dynamics, fluid-structure interaction and heat transfer) operating at different spatial and temporal scales. A lubricated transmission model is proposed in this work to obtain accurate information regarding all physical domains and the coupling thereof to quantify performance, efficiency and durability. The model consists of a thermo-elastically coupled flexible multibody model for the gear pair and a Thermo-Elasto-Hydrodynamic Lubrication (TEHL) model for the lubricant, both based on first principle modelling to ensure high fidelity

EEAS 2.0: draft recommendations for the 2013 EEAS Review

This document offers recommendations for the amendment of Council Decision 2010/427/EU establishing the organisation and functioning of the European External Action Service (hereinafter ‘EEAS Decision’). These recommendations have been distilled from discussions between academics and practitioners during a two-day workshop held at the European University Institute in March 2013 in the framework of the so-called ‘EEAS 2.0’ project. This research project is a collaboration between independent scholars brought together by SIEPS, the EUI and CEPS. In February 2013, the team published a legal commentary on the EEAS Decision, available on the websites of the participating research centres. The current paper and its recommendations should be read in the light thereof. In formulating the recommendations, attention has been paid to policy papers, non-papers and recommendations that have been initiated by EU institutions, member states, think tanks and academia, notably in the context of the on-going review. As such, we hope to be able to inform, in a precise and legal way, the discussions in preparation of the High Representative’s own report. The current paper is work in progress and will be revisited for publication after the summer, taking into account the High Representative’s report of July and feedback from other stakeholders The current paper sheds light on possible adjustments in the operation of the Decision/Service ‘à droit constant’, but also includes proposals that could be considered in the context of an amendment of the EEAS Decision. With regard to the latter, several levels of revision may be envisaged: (i) a mere toilettage (e.g. deleting out-dated provisions and securing terminological consistency), (ii) technical changes in the text without reopening the political discussion that predated the adoption of the Decision and (iii) a more ambitious revision that could require more extensive legal modifications of collateral secondary measures (e.g. Staff and/or Financial regulations), if not of the founding treaties

Wind turbine drivetrains:State-of-the-art technologies and future development trends

This paper presents the state-of-the-art technologies and development trends of wind turbine drivetrains – the system that converts kinetic energy of the wind to electrical energy – in different stages of their life cycle: design, manufacturing, installation, operation, lifetime extension, decommissioning and recycling. Offshore development and digitalization are also a focal point in this study. Drivetrain in this context includes the whole power conversion system: main bearing, shafts, gearbox, generator and power converter. The main aim of this article is to review the drivetrain technology development as well as to identify future challenges and research gaps. The main challenges in drivetrain research identified in this paper include drivetrain dynamic responses in large or floating turbines, aerodynamic and farm control effects, use of rare-earth material in generators, improving reliability through prognostics, and use of advances in digitalization. These challenges illustrate the multidisciplinary aspect of wind turbine drivetrains, which emphasizes the need for more interdisciplinary research and collaboration

18F-FDG PET/CT for diagnosing infectious complications in patients with severe neutropenia after intensive chemotherapy for haematological malignancy or stem cell transplantation

Item does not contain fulltextPURPOSE: Between 30 and 50% of febrile neutropenic episodes are accounted for by infection. C-reactive protein (CRP) is a nonspecific parameter for infection and inflammation but might be employed as a trigger for diagnosis. The aim of the study was to evaluate whether (18)F-fluorodeoxyglucose (FDG) positron emission tomography (PET)/CT can be used to detect inflammatory foci in neutropenic patients with elevated CRP and whether it helps to direct treatment. METHODS: Twenty-eight consecutive patients with neutropenia as a result of intensive chemotherapy for haematological malignancies or myeloablative therapy for haematopoietic stem cell transplantation were prospectively included. (18)F-FDG PET/CT was added to the regular diagnostic workup once the CRP level rose above 50 mg/l. RESULTS: Pathological FDG uptake was found in 26 of 28 cases despite peripheral neutrophil counts less than 0.1 x 10(-9)/l in 26 patients: in the digestive tract in 18 cases, around the tract of the central venous catheter (CVC) in 9 and in the lungs in 7 cases. FDG uptake in the CVC tract was associated with coagulase-negative staphylococcal bacteraemia (p < 0.001) and deep venous thrombosis (p = 0.002). The number of patients having Streptococcus mitis bacteraemia appeared to be higher in patients with grade 3 oesophageal FDG uptake (p = 0.08). Pulmonary FDG uptake was associated with the presence of invasive fungal disease (p = 0.04). CONCLUSION: (18)F-FDG PET/CT scanning during chemotherapy-induced febrile neutropenia and increased CRP is able to detect localized foci of infection and inflammation despite the absence of circulating neutrophils. Besides its potential role in detecting CVC-related infection during febrile neutropenia, the high negative predictive value of (18)F-FDG PET/CT is important for avoiding unnecessary diagnostic tests and therapy.1 januari 201

Analytical geometry of modified involute gears generated by means of rack-type cutters

nrpages: 12status: publishe

Strengthening the strategic choice offered to the EU’s southern Mediterranean neighbours. CEPS Commentary, 1 February 2013

Finding that the European Neighbourhood Policy (ENP) currently lacks a strategic vision that would offer states in the southern Mediterranean substantial returns in exchange for making tough reforms, this CEPS Commentary suggests that this weakness can be overcome through a concrete prospect of regional integration pro-actively driven forward by the European Union. Taking inspiration from current projects such as the Energy Community Treaty, the authors urge the EU to explicitly incorporate “legally binding sectoral multilateralism” into the ENP. This would provide the Union’s partners with a tangible prospect of reaping real long-term benefits from EU cooperation and reinvigorate the ENP for the next decade

EEAS 2.0: Recommendations for the amendment of Council Decision 2010/427/EU on the European External Action Service. CEPS Special Report No. 78, 13 November 2013

This Special Report offers recommendations for the amendment of the Council Decision 2010/427/EU establishing the organisation and functioning of the European External Action Service. Its purpose is to contribute, in practical legal terms, to the ongoing review of the Decision in 2013, as well as to the possible discussion on its revision that may take place in 2014. In particular, it sheds light on possible adjustments in the application of the Decision ‘à droit constant’, but also suggests potential alteration of its formulation

A nonlinear parametric model reduction method for efficient gear contact simulations

© 2014 John Wiley & Sons, Ltd. © 2014 John Wiley & Sons, Ltd. Summary: A novel nonlinear parametric model order reduction technique for the solution of contact problems in flexible multibody dynamics is presented. These problems are characterized by significant variations in the location and size of the contact area and typically require high-dimensional finite element models having multiple inputs and outputs to be solved. The presented technique draws from the fields of nonlinear and parametric model reduction to construct a reduced-order model whose dimensions are insensitive to the dimensions of the full-order model. The solution of interest is approximated in a lower-dimensional subspace spanned by a constant set of eigenvectors augmented with a parameter-dependent set of global contact shapes. The latter represent deformation patterns of the interacting bodies obtained from a series of static contact analyses. The set of global contact shapes is parameterized with respect to the system configuration and therefore continuously varies in time. An energy-consistent formulation is assured by explicitly taking into account the dynamic parameter variability in the derivation of the equations of motion. The performance of the novel technique is demonstrated by simulating a dynamic gear contact problem and comparing results against traditional model reduction techniques as well as commercial nonlinear finite element software. Copyrightstatus: publishe

Interpolation strategies for non-linear parametric model order reduction in gear contact simulation

status: publishe