Search results for "rake"
showing 10 items of 866 documents
Imagología: un emblema holandés del siglo XVIII sobre la imagen del español
2009
El presente artículo analiza el emblema «De Spanjaart» [«El español»] del libro StichtelykZinnebeelden [Emblemas edificantes] de Arnold Houbraken y GezineBrit (Amsterdam, 1723) a la luz de los estereotipos que sobre la imagen de los españoles prevalecían por entonces en Holanda y en el contexto de la disciplina de la Imagología. The present article analyzes the emblem «De Spanjaart» [«The Spaniard»] from the book Stichtelyk Zinnebeelden [Edifying Emblems] by Arnold Houbrakenand Gezine Brit (Amsterdam, 1723) in the light of the stereotypes of the image of Spaniards prevalent in Holland at that time and in the context of the discipline ofImagology (Imagestudies).
Cutting Temperatures Evaluation in Ceramic Tools: Experimental Tests, Numerical Analysis and SEM Observations
1994
The authors propose a multiple approach for the evaluation of cutting temperatures in ceramic tools. The first approach was the experimental evaluation of equitemperature lines, obtained in three-dimensional cutting by employing constant melting point powders scattered on planes parallel to rake face. In the second approach, a numerical finite element analysis was performed. At this step the determination of the percentage of total heat produced in the operation that flows into the tool was considered and, consequently, the temperature distribution within the whole volume of the insert. Finally, the examination of the crater zone with SEM microscopy confirmed the temperature levels as previ…
Braking procedure analysis of a pegs-wing ventilated disk brake rotor
2006
Fade test results of a ventilated disk brake rotor with pegs-wing performed by means of an inertia dynamometer, consisting of 14 repeated brake applications from an initial brake speed of 160 km/h down to 0 km/h, with constant deceleration are shown. The first brake application test results are compared to the FEM numerical predictions with MSC Visual Nastran on the entire disk. These conform well to the experimental data, although numerical thermal field is slightly higher than the experimental one. Besides, ventilated disk brake rotor shows great dimensional stability and the ability to dissipate a great amount of thermal flow.
Experimental investigation on high efficiency real-time control algorithms for IPMSMs
2014
This paper describes an experimental investigation on the power losses variations occurring in an Interior Permanent Magnet Synchronous Motor (IPMSM) with respect to the direct axis current component. Such investigation can be useful to determine a mathematical model accounting for copper, iron and mechanical friction losses, and for the arrangement of a speed control drive system equipped with a real-time power losses minimization algorithm. In particular, a test bench has been set up in order to carry out all measurements and the final power loss identification. The test bed is composed by a IPMSM drive with a field oriented control (FOC) strategy, a power analyzer, a dynamometric brake a…
Thermal stress analysis of different full and ventilated disc brakes
2015
During the braking phase, the heat produced by friction between pads and disc cannot be entirely dissipated. Consequently, the brake disc, especially if very hard braking occur, can accumulate large amounts of heat in a short time so producing high gradients of temperature on it. Under these conditions, functionality and safety of the brake system can be compromised. The object of this study is to investigate, under extreme working conditions, the thermomechanical behaviour of different brake rotors in order to evaluate their efficiency and stability and to identify any compromising weakness on them. In particular, by means of FEM thermo-mechanical coupled analyses, one full disc and three …
Practical Application of Eddy Currents Generated by Wind
2011
When a conductive material is subjected to time-varying magnetic fluxes, eddy (Foucault) currents are generated in it and magnetic field of opposite polarity as the applied one arises. Due to the internal resistance of the conductive material, the eddy currents will be dissipated into heat (Joule heating). Conventional domestic water heaters utilize gas burners or electric resistance heating elements to heat the water in the tank and substantial part of the energy to use for it is wasted. In this paper the origin of electromagnetic induction heat generated by wind turbine in special heat exchange camera connected to water boiler is discussed and material evaluation performed using mathemati…
Multicriteria evaluation of sustainable energy solutions for Colosseum
2017
Abstract Colosseum is a large office building in the capital region of Finland. The building owner operates on the highly competitive office rental market. With increasing emphasis on environmental responsibility, energy efficiency and sustainable energy solutions can provide competitive edge on the rental market. This study evaluates in terms of multiple criteria different alternatives to enhance the energy solutions of the building. The alternatives included different configurations of solar power, ground source heat, and roof constructions, along with district heating. Decision criteria included internal rate of return, energy efficiency, CO2 emissions, and attractiveness. Attractiveness…
The mechanics of continuous chip formation in oblique cutting with single-edged tool—part II. Experimental verification of the theory
1990
Abstract Experimental results obtained during oblique cutting of annealed steel Ck 45 (SAE-AISI 1045) with a single-edged tool are presented. Extensive measurements of forces, cutting ratio, chip flow angle etc. have been carried out under a wide range of cutting conditions. The measured data obtained from these cutting tests are used to test assumptions proposed in the first part of this work. In relation to previous works dealing with oblique cutting problems the present one extends to tools with angles of tool obliquity ranging from 30° to 70° and having a large negative rake angle.
Analytical Models Based on Composite Layer for Computation of Tool-Chip Interface Temperatures in Machining Steels with Multilayer Coated Cutting Too…
2005
In this study the method of elementary balances (MBE) is applied to predict the temperature fields in uncoated and coated carbide cutting tools. Numerical computations are supported by the experimentally/analytically obtained values of the contact length, the total heat flux and the heat partitioning. The changes in the tool temperature maps, resulting from variable thermal properties of tested materials are considered. In particular, the distribution of temperature across the thin film of 0.01 mm and corresponding temperature rise distribution curves along the rake and flank faces are completely displayed. The simulations have been validated against the measured average rake face temperatu…
The COVID-19 Impact on Bucharest Stock Exchange. The First Six Months
2020
Abstract The first case of coronavirus was registered in Romania on February 26. From this moment, Romania has become “infected”, just like the whole world, and the economy has suffered milder or more severe symptoms, depending on the activity field. Four months have passed since then, during which in Romania, the effects of the health crisis overlapped with a tense political situation, in an unfavorable economic context. Once the COVID-19 hits each country, the economic effects started to become visible in all the world’s financial markets, the financial market being among the first to suffer the impact of the COVID-19 crisis. This paper analyzes how the financial market in Romania was aff…