Sorin VLASE


29-81 REZULTATE PRELIMINARE PRIVIND STABILIREA EXPERIMENTALĂ A MĂRIMII COEFICIENTULUI DE FRECARE LA ROSTOGOLIRE

PRELIMINARY RESULTS CONCERNING ON EXPERIMENTAL
DETERMINATION OF THE ROLLING FRICTION COEFFICIENT
The authors, in their preliminary investigations [xxxx], conceived an
original testing bench, in order to establish the magnitude of the rolling friction
coefficient.
Involving the mentioned testing bench, the authors started to perform
some preliminary experimental investigations in several tribo-couples, foreseen
with thin plastic cover layer.
In the described investigations, the authors offer useful correlations
between the thickness of the layers and the magnitude of the rolling friction
coefficient.
Their next topic will consist in combining different tribo-couples, having
covered and uncovered elements, in order to diminish as soon as possible the
magnitude of the rolling friction coefficient.
One has to underline the fact that the proposed original methodology
will represent in the next period a high-accuracy approach in the evaluation of
the rolling friction coefficient, corresponding to different pairs of elements, which
constitute the tribo-couple.
Keywords: rolling friction coefficient, experimental evaluation, original
testing bench
Cuvinte cheie: coeficient de frecare la rostogolire, investigaţii
experimentale, stand original pentru teste

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29-79 TESTE DE ÎNCOVOIERE ASUPRA SANDWICH-ULUI COMPOZIT DE TIP CELLITE

BEND TESTS ON CELLITE COMPOSITE SANDWICH
In this paper, three-point bend tests have been accomplished on
CELLITE composite sandwich to determine the flexural properties of this kind of
structure. Load-deflection distributions until break and at 50 mm deflection have
been carried out on a LR5K PLUS Lloyd’s Instruments materials testing
machine using the NEXYGEN PLUS software.
Keywords: test bending, composite sandwich, Cellite, load-strain
distributions
Cuvinte cheie: test încovoiere, sandwich compozit, fibră celit, distribuţii
forţă-deformaţie

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28-3 CONSIDERAŢII PRIVIND ANALIZA STRUCTURAL-DINAMICĂ PENTRU O TURBINĂ EOLIANĂ DE MICĂ PUTERE CU AX VERTICAL

CONSIDERATIONS ON THE DYNAMIC STRUCTURAL DESIGN FOR A SMALL POWER VERTICAL AXIS WIND TURBINE
The paper presents the main aspects regarding the dynamic structural design for a small power vertical axis wind turbine. The research is applied to a 3-bladed, Darrieus type, small power, vertical axis wind turbine installed on a self-standing pole. First the main sources for the dynamic forces acting on the structure are described. Then a complete investigation on the turbine structural response is done, performing a modal analysis applied to the single rotor, considering several rotational speeds. Next, taking into consideration a building integrated wind turbine, the system composed by the turbine rotor and the mast is investigated. Finally, a thorough discussion of the main implementation problems and design alternatives is presented for a building integrated wind turbine.
Keyword: small power vertical axis wind turbines, modal analysis, Campbell diagram, urban implementation
Cuvinte cheie: analiză modală, turbine eoliene de mică putere cu ax vertical, implementare urbană, diagrama Campbell

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27-79 CONSIDERAŢII PRIVIND ÎMBUNĂTĂŢIREA TIPULUI DE ÎNCERCARE AL ADEZIVILOR

CONSIDERATIONS ON THE ADHESIVE TESTING
TYPE’S IMPROVEMENT
The authors of the contribution analyse several types of the specimens, involved in the adhesives’ testing protocol. Based on the results of the Finite Element analysis, respectively of the experimental investigations ones, by means of Holographic Interferometry, they suggest a new type of specimen, which assures a more accurate evaluation of the pure shear effect in the adhesive layer. Also, their original testing stand destined to Holographic Interferometry investigations, described in an earlier contribution, can be efficiently involved in this new type of investigation of the adhesives.
The most critical issue consists of the high-accuracy determining of the shear strength of the adhesive layer, without the bending’s additional effect.
The proposed methodology and type of the specimen offer the adequate answer. The author’s further goal consists in involving this new approach in different kind of adhesives’ examination.
Keywords: Adhesive, shear resistance, Holographic Interferometry, specimen, testing stand
Cuvinte cheie: adeziv, rezistenţa la forfecare, Interferometria Holografică, epruvetă, stand pentru teste

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