Arhivă Revista

32-66 CONSIDERAȚII PRIVIND IMPACTUL DINTRE UN PARAPET DE PROTECȚIE ŞI UN PENDUL

Această intrare a fost publicată în 2017 Volumul 32 și etichetată Maria – Adriana CORDOȘ Mircea BEJAN la de

CONSIDERATIONS REGARDING THE IMPACT OF A PROTECTIVE BARRIER AND A PENDULUM

 

The paper presents the impact of a pendulum with a weight of 2780 kg and a road protective barrier used on the roads of Romania. Deformable parapets are very important to protect the pedestrians and the vehicles on our roads. The maximum dynamic deflection of the parapet, measured after the test was 0,240 m and 0,435 m of working width.

The barrier was deformed as expected. Damping elements have taken a large amount of energy during impact. The pendulum is used by researchers in this field. This is a very good way to track the behavior and damping elements of the barriers in the laboratory.

 

Keywords: shock test, road restraint systems

Cuvinte cheie: încercare la şoc,  sisteme de reținere rutiere

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32-65 TESTE EXPERIMENTALE PE DISCUL BIPLAN AL VANEI FLUTURE

Această intrare a fost publicată în 2017 Volumul 32 și etichetată Cristian Marius MIMIS Tiberiu Ștefan MĂNESCU la de

EXPERIMENTAL TESTS ON A BUtTERFLY

VALVE BIPLAN DISC

 

The paper present the obtained experimental results after laboratory tests on a butterfly valve biplane disc by using electrical resistive tensometry method. Measuring the variation of the sensor’s resistance through electrical methods is proportionally with its elongation and the deformation of the part of the butterfly valve disc. The measured elongations for three static loads applied on the valve disc are presented.

 

Keywords: deformations, biplane butterfly valve disc, tensometers electro-resistive

Cuvinte cheie: deformaţii, disc biplan vană fluture, tensometrie electro-rezisitivă

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32-64 REZULTATE PRELIMINARE PRIVIND UTILIZAREA METODEI CORELĂRII DIGITALE A IMAGINII ÎN STUDIUL IMPLANTURILOR DENTARE

Această intrare a fost publicată în 2017 Volumul 32 și etichetată Daniel-Tamás SZÁVA Gabriel POPA Holger HOŢA Ildikó-Renáta SZÁVA Ioan SZÁVA Pál Botond GÁLFI la de

PRELIMINARY RESULTS CONCERNING ON THE IMPLEMENTATION OF THE VIDEO IMAGE CORRELATION METHOD IN THE DENTAL IMPLANTS ANALYSIS

 

The authors, in their preliminary investigations [1; 2; 3], conceived an original testing bench, destined to human mandibles’ strain-state evaluation.

Involving the mentioned testing bench, the authors started to perform some preliminary experimental investigations in several dental implants’ behaviours.

In the described investigations, the authors some useful correlations between the dental implant’s positioning on the mandible, the applied mastication force magnitude and its relative 3D positioning with respect to the implant’s longitudinal axis.

Their next topic will consist in a searching examination of the optimal positioning of the implants, with respect to their loading conditions.

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 strain-state analysis of the dental implants.

 

Keywords: dental implant, testing bench, displacement field, Video Image Correlation

Cuvinte cheie: implant dentar, stand de încercat implanturi, câmp de deplasare, Corelare Digitală a Imaginii (VIC)

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32-63 CONSIDERAȚII ASUPRA TENSIUNILOR ȘI DEFORMAȚIILOR DIN CADRELE PRESELOR DE MARE TONAJ

Această intrare a fost publicată în 2017 Volumul 32 și etichetată Daniel Gheorghe LAKATOS Ioan VIDICAN Marius PÂSLĂ Mircea BEJAN la de

CONSIDERATIONS ON THE FRAMES STRESSES

AND STRAINS HEAVY PRESSES

 

In paper presents a theoretical study of the state of stress and strain in the machine frame framework heavy press. These frameworks are made up of a plurality of frames each comprised of two closed C-shaped elements (calipers) connected by tightening by means of threaded rods (Fig. 1)

 

Keywords: press, frame, strength, stress, deformations, thrusts

Cuvinte cheie: presă, batiu, forță, tensiuni, deformații, tirant

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32-62 APLICATII ALE METODELOR NUMERICE DE CALCUL ÎN ANALIZA COMPORTĂRII VANELOR FLUTURE BIPLANE

Această intrare a fost publicată în 2017 Volumul 32 și etichetată Cristian Marius MIMIS la de

APPLICATIONS OF THE NUMERICAL METHODS IN ANALYZE THE BEHAVIOR OF BIPLANE BUTTERFLY VALVES

 

The paper presents the elongations obtained by numerical results on a butterfly valve biplane disc by using finite element method and these values were compared with elongations resulted from laboratory tests for three levels of water pressure applied upstream the biplane disc. The comparison between two methods to determine the elongation it shows that the finite element method applied to the disc can replace electrical resistive tensometry, to compute stresses and deformations for biplane butterfly disc on an industrial scale.

 

Keywords: finite element method, disc biplane specific strain

Cuvinte cheie: metoda elementelor finite, disc biplan, deformaţii specifice

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32-61 ANALIZA STĂRII DE TENSIUNI ŞI DEFORMAŢII ÎN CORPURILE DE RULARE DE MICI DIMENSIUNI

Această intrare a fost publicată în 2017 Volumul 32 și etichetată Gelu BĂLAN Ovidiu MILOȘ Tiberiu Ștefan MĂNESCU Vasile IANCU la de

STRESS AND STRAIN ANALYZE OF

SMALL ROTATION BODIES OF BEARINGS

 

In the paper is presented the study of tensions and strains ho appears in small radial roller bearings during the compressive strength testing caused by forces acting perpendicular to the roller generator. For modelling a roller bearing Ø 16×24 [mm] we used SolidWorks program, the tests were conducted on two types of rollers with and without defect loaded in five-speeds charging.

 

Keywords: reel, bearing, local deformation, finite element

Cuvinte cheie: rolă, rulment, deformaţie locală, elemente finite

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32-60 STUDIUL STĂRII DE TENSIUNI ȘI DEFORMAȚII ALE ROLELOR DE RULMENT PRIN MODELARE CU METODA ELEMENTELOR FINITE

Această intrare a fost publicată în 2017 Volumul 32 și etichetată Gelu BĂLAN Ovidiu MILOȘ Tiberiu MĂNESCU jr. Vasile IANCU la de

STRESS AND STRAIN STUDY OF THE ROLLER BEARINGS USING FEM METHOD

 

This paper aims to study the stresses and strains that occur in small radial bearings with rolls of Æ 7,5×15 mm diameter. We have considered five-speed charging for two distinct cases: without and with defects.

 

Keywords: roller bearing, contact voltage, strain, roll flange

Cuvinte cheie: rulment radial, tensiune de contact, deformație, rolă-placă plană

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32-59 EFICIENŢA DIFERIŢILOR ESTIMATORI AI DISIMILARITĂŢII UTILIZAŢI ÎN DETECTAREA DEFECTELOR

Această intrare a fost publicată în 2017 Volumul 32 și etichetată Gilbert Rainer GILLICH Ionela PELEA Nicoleta GILLICH la de

THE EFFICIENCY OF SEVERAL DISSIMILARITY ESTIMATORS USED IN DAMAGE DETECTION

 

This paper deals with damage detection methods based on interpreting the results of vibration measurement. We briefly described an own method for damage evaluation, which takes into account a large number of frequencies achieved from weak axis bending modes. This allows the precise location of the defect location. We represented two histogram types, one with measurements and several resulted from calculations for possible damage scenarios. The damage location was determined with three estimators, among those the best results being attained with the Minkowski distance.

 

Keywords: damage, severity assessment, natural frequencies, vibration

Cuvinte cheie: defecte, evaluarea severității, frecvenţe naturale, vibraţii

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32-58 MODIFICAREA DISTRIBUŢIEI TENSIUNILOR ÎN ZONA DEFECTULUI ŞI EFECTUL ACESTEIA ASUPRA FRECVENŢELOR PROPRII ALE GRINZII

Această intrare a fost publicată în 2017 Volumul 32 și etichetată Gilbert Rainer GILLICH Luminiţa PĂDURARU Marius TUFOI la de

STRESS DISTRIBUTION ALTERATION IN THE DAMAGED ZONE AND ITS EFFECT ON THE BEAM’S NATURAL FREQUENCIES

 

In this paper the relation to be used for deriving the frequency of a beam with transverse crack is tested against finite elements method (FEM) simulation results. We have first analytically derived the beam deflection and compared with results achieved by means of the FEM simulation. The good concordance was found, thus the FEM model is calibrated. Afterwards, damage of different depth was introduced in the beam and the natural frequencies derived. These values were compared against results attained by applying the proposed relation and a good fit was found.

 

Keywords: beam, damage detection, vibration, natural frequencies, deflection

Cuvinte cheie: grindă, detectarea defectelor, vibraţii, frecvenţe proprii, săgeată

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32-57 DESPRE MODIFICAREA FRECVENŢELOR NATURALE ALE GRINZILOR DATORITĂ COROZIUNII

Această intrare a fost publicată în 2017 Volumul 32 și etichetată Emilian STANCIU Gilbert Rainer GILLICH Zeno-Iosif PRAISACH la de

ON THE NATURAL FREQUENCY CHANGES OF

BEAMS DUE TO CORROSION

 

This paper presents a relation to be used for deriving the effect of mass loss on the natural frequencies of beams. Herein the stiffness decrease is not considered, since its effect on the natural frequencies is well-known. Consequently, the beam was considered with a constant cross-section but with reduced volumetric mass density in the corroded region. By this approach, we have first analytically studied the beam dynamics from an energetic point of view and contrived the mathematical relation. Afterwards, this relation was successfully tested against FEM simulations.

 

Keywords: beam, corrosion, vibration, natural frequencies, mode shape

Cuvinte cheie: grindă, coroziune, vibraţii, frecvenţe naturale, formă modală

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32-56 OPTIMIZAREA TOPOLOGICĂ A STRUCTURILOR ÎN INGINERIE

Această intrare a fost publicată în 2017 Volumul 32 și etichetată Alexandra-Daniela SCURTU Ancuţa Nadia JURCO Horea-George CRIȘAN Iacob-Liviu SCURTU la de

TOPOLOGICAL OPTIMIZATION OF THE STRUCTURE IN ENGINEERING

 

Nowadays the rapid development of the industry required use the optimization method. First part of this study shows the structural optimization method used in mechanical enginnering, being made a detailed explanation of the iterative optimization process. In the second part of the paper is presented the CAD modelling and the topological optimization of the holder used in mechanical engineering. the results of the optmization study and the conclusions are presented at the end of this paper.

 

Keywords: topological optimization, finite element analysis, objective functions

Cuvinte cheie: optimizare topologică, analiza cu elemente finite, funcții obiectiv

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32-55 SIMULAREA NUMERICĂ A UNEI VANE DE ECLUZĂ DE LA HIDROCENTRALA PORȚILE DE FIER I

Această intrare a fost publicată în 2017 Volumul 32 și etichetată Ioan LAZA Paul-Dan OPRIȘA-STĂNESCU Tiberiu Dimitrie BABEU la de

NUMERICAL ANALYSIS OF A LOCK VALVE

OF IRON GATE I HYDRO

 

One of the valves of the intermediate head of the lock of Iron Gate I Hydroelectric Power Station was damaged; it was replaced by another version. In order to elucidate the cause of the damage was done a numerical simulation using ANSYS Fluent software. The simulation has required the modeling of parts of channel for filling/emptying of the lock, taking also into account the hydrostatic water pressure, not just those static or dynamic. The paper presents a modeling of steady flow through the valve which is in a certain position, which shows velocity and pressure fields and the forces on the faces of the valve.

 

Keywords: lock, water navigation, valve, Iron Gate I Hydroelectric Power Station, numerical analysis, ANSYS Fluent

Cuvinte cheie: ecluză, vană, hidrocentrala Porțile de Fier I, simulare numerică, ANSYS Fluent

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32-54 METODĂ HIBRIDĂ DE STUDIU PENTRU ORICE TIP DE SECȚIUNE SUPUSĂ LA TORSIUNE

Această intrare a fost publicată în 2017 Volumul 32 și etichetată Ghiţă BÂRSAN Vasile NĂSTĂSESCU la de

A HYBRID MeTHOD OF STUDY FOR ANY SECTION

TYPE UNDER TORSIONAL LOADING

 

This paper presents a methodology regarding the numerical analysis of any section type under torsion loading. This methodology is named a hybrid one, because it practically consist in using of the membrane analogy – an experimental method –  but the solving and result analysis are made by Finite Element Method (FEM). In the modelling of a structure, of a beam, applying of the torsion moment involves some difficulties especially regarding of the local stress concentration. By the methodology presented in this paper, the analysis of the shear stress field can be made with a great accuracy using FEM, without any experimental means. This methodology takes into account all the physical significations of the membrane analogy and all these are evaluated by FEM. That require of the pressure-effort ratio to be -2 is made by a thermal loading, cooling the membrane. By post-processing, the numerical result analysis can be quickly and easily made. The modelling presented in this paper can be used for any section type: whatever the shape, no matter if the section has one or more holes etc. By this methodology, the membrane analogy becomes more efficient, more versatile and more accessible for any section type.

 

Keywords: torsion, membrane analogy, finite elements

Cuvinte cheie: torsiune, analogia cu membrana, elemente finite

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32-53 ȘCOALA DE REZISTENȚA MATERIALELOR DIN UNIVERSITATEA POLITEHNICA DIN BUCUREȘTI

Această intrare a fost publicată în 2017 Volumul 32 și etichetată Costică ATANASIU Nicolae ILIESCU la de

SCHOOL OF STRENGTH OF MATERIALS FROM POLYTECHNIC UNIVERSITY OF BUCHAREST

 

Strength of Materials School of the Polytechnic University of Bucharest has a history of nearly 150 years attested. The paper presents the steps taken by the Strength of Materials School, closely related to evolution University, personalities that contributed to the formation and development of this school, the laboratory created and its involvement in solving of problems in economy and priority directions in research.

The conclusions of the paper highlight the conditions in which it forms a school for it to persist and grow.

 

Keywords: strength of materials, stability of construction, engineering school, electrical strain gauge technique, vibrations

Cuvinte cheie: rezistenţa materialelor, stabilitatea construcţiilor, şcoală de inginerie, tensometrie electrică, vibraţii

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32-52 STUDIU DE CAZ ASUPRA TERMOIZOLAŢIILOR CLĂDIRILOR CU MATERIALE ORGANIC – NATURALE

Această intrare a fost publicată în 2017 Volumul 32 și etichetată Doru Cristian BRATU la de

CASE STUDY ON THERMAL INSULATION IN BUILDINGS WITH ORGANIC – NATURAL MATERIALS

 

Reducing energy consumption through the thermal insulation of buildings, including insulation using materials of organic-natural origin is a current concern of specialists. The paper analyses energy rehabilitation solutions with various materials of organic-natural origin, proving the efficiency of using low density thermo isolating materials, as well as the efficiency of using small amounts of renewable primary energy in the production of said materials.

 

Keywords: building, thermal insulation, energy consumption, material, organic, natural

Cuvinte cheie: clădire, izolaţie termică, consum energetic, material, organic, natural

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32-51 DESPRE COMPANIA HEIDELBERG CEMENT ROMÂNIA S.A.

Această intrare a fost publicată în 2017 Volumul 32 și etichetată Nicolae FÂNTÂNARU la de

REGARDING THE COMPANY HEIDELBERG CEMENT ROMÂNIA S.A.

 

The document contains the presentation of the company Heidelberg Cement Romania S.A. and its activity for carrying out sustainable constructions. The company is present in our country since 1998, with investments of over 450 million Euro, holding the honorary title of „Supplier for the Royal House of Romania“.

 

               Key words: the company Heidelberg Cement Romania S.A., sustainable constructions

Cuvinte cheie : compania Heidelberg Cement România S.A., construcții durabile

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32-50 STUDII ȘI COMPARAȚII ALE MATERIALELOR HIDROIZOLATOARE DE PROTECȚIE A INFRASTRUCTURII

Această intrare a fost publicată în 2017 Volumul 32 și etichetată Mihaela DUMITRAN la de

STUDIES AND COMPARISONS OF WATERPROOFING MATERIALS FOR INFRASTRUCTURE PROTECTION

 

This article mainly illustrates the current situation of dedicated infrastructure materials as well as the comparison of some of them. For the waterproofing system comparison, one of the multi-criteria analysis methods was used: the Global Utility Method. The proposed analysis scenarios were: bituminous waterproofing for a continuous foundation, HDPE waterproofing for a continuous foundation and waterproofing based on additives for concrete, for a continuous foundation. Our multi-criteria analysis was based on the following features of the technology execution process: price, life span and degree of difficulty.

 

Keywords: waterproofing, foundation, multi-criterial analysis,  global utility method

Cuvinte cheie: hidroizolații, fundație, analiza multicriterială, metoda utilități globale

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32-49 ANALIZA ALUNECĂRILOR DE TEREN PRIN METODE GEODEZO-TOPOGRAFICE ȘI MODELARE 3D

Această intrare a fost publicată în 2017 Volumul 32 și etichetată Iulia Diana GLIGA Maria-Olivia MOLDOVAN la de

ANALYSIS OF LANDSLIDES THROUGH GEODETIC-TOPOGRAPHICAL METHODS AND 3D MODELING

 

The aim of the landslides study, located on the southern slope of the Cetățuie Hill (urban zone, Gruia neighbourhood, Cluj-Napoca City) is to create a geodetic-topographic plan and documentation that can be used specifically in planning and predicting erosion of slopes. In this study case was used the topographic documentation for hazard assessment of landslides. For the plan metrical and nivelitic surveying were used national geodetic network points of support supplemented with thickening points (due to work), in order to use them as starting and closing elements for determining the survey control In order to determine the points of land used for the survey network, a Pentax R – 322NX Total Station was used. Creating a 3D model from the data collected in the field was done using TopoLT and Surfer.

 

Keywords: landslides, planning and predicting erosion, topographic plan, 3D model

Cuvinte cheie: alunecări de teren, prevenirea eroziunii, plan topografic, model 3D

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32-48 ORGANIZAREA EFICIENTĂ A RESURSELOR UMANE ŞI MATERIALE PENTRU EFICIENTIZAREA UNUI PROCES DE CONSTRUCŢIE

Această intrare a fost publicată în 2017 Volumul 32 și etichetată Dorina SUCALĂ Ilie-Nicolae SUCALĂ Mihaela DUMITRAN la de

EFFICIENT ORGANIZATION OF HUMAN AND

MATERIAL RESOURCES TO STREAMLINE

THE CONSTRUCTION PROCESS

 

Concern about duration in which a building can be achieve, has been and remains one of the main problems of any specialist in this sphere of activity. Conception, design and implementation of a project require a constant monitoring the parameters of prediction, planification and supervision way works. Company management can be considered a discipline with economic character because its purpose is increasing economic efficiency

 

Keywords: construction activities, work productivity, processes, efficiency

Cuvinte cheie: activități de construcții, productivitatea muncii, procesele, eficiența

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32-47 PRINCIPII ȘI SISTEME DE CERTIFICARE A CLĂDIRILOR ÎN CONTEXTUL DEZVOLTĂRII DURABILE

Această intrare a fost publicată în 2017 Volumul 32 și etichetată Daniela Lucia MANEA Iacob FLOREA la de

PRINCIPLES AND SYSTEMS CERTIFICATION OF BUILDINGS IN THE CONTEXT OF SUSTAINABLE DEVELOPMENT

 

The problem of constructing energy-efficient buildings and sustainable is increasingly present in recent years because their owners want to reduce energy consumption, carbon footprint reduction and maintenance costs. Created for this purpose or systems of assessment and certification of buildings in the context of sustainable development. The paper deals with the main building certification systems that are based on multi-criteria evaluation methodology following: raising awareness of the beneficiaries, design, construction, operation and promotion of integrated design practices.

 

Keywords: sustainability development, environmental certification systems, energetic efficiency, environment, pollution, building, valuation method, climate change, interior comfort

Cuvinte cheie: dezvoltare durabilă, sisteme de certificare ambientală, eficiență energetică, mediu, poluare, construcții, metodă de evaluare, schimbare climatică, confort interior

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32-46 ANALIZA TENSIUNILOR DE TURNARE ÎNTR-O PIESĂ TIP REȚEA DE CONTRACȚIE

Această intrare a fost publicată în 2017 Volumul 32 și etichetată Marius Dan CRIȘAN Tiberiu LEHENE Vasile Filip SOPORAN la de

STRESS ANALYSIS OF CASTING IN A PART NETWORK TYPE CONTRACTION

 

This paper presents a study on how the occurrence and distribution of tensions casting a piece of „network contraction” or „yoke of contraction”. It makes a comparative analysis of the results provided by the aluminium alloy solidification simulation EN AC-Al Si7Mg0,3 cast in the mould of the classic mix of training and experimental results obtained by casting the play of the same alloy and in the same conditions and by cutting its determination tensions.

 

Keywords: thermal stress, aluminum alloy, castings

Cuvinte cheie: stres termic, aliaj de aluminiu, piese turnate

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32-45 MANUFACTURAREA ADITIVĂ – TEHNOLOGIE DE PERSPECTIVĂ ÎN PROCESAREA MATERIALELOR PRIN TURNARE

Această intrare a fost publicată în 2017 Volumul 32 și etichetată Emil NAGY la de

ADDITIVES MANUFACTURING A TECHNOLOGICAL

FUTURE IN MATERIALS PROCESSING BY CASTING

 

Material processing by casting requires the use of various types of raw materials, numerous auxiliary materials, various forms of energy and technological fluids flowing through varied route in several specific types of plant and machinery. The changes that have occurred in industrial technologies for the past 20 years under the new paradigm „changing technologies under the influence of the economic, social and political” and left their mark on the field for obtaining substantial and parts by processing materials by casting. Recent decades have marked the appearance in the current industrial operation in the processing of materials, concerns more highly bound to reduce and optimize energy consumption and materials linked with improving the environment. This development has led to the widening, deepening and broadening the scope in order of the best processing methods to ensure the sustainable development as on real. As such materials processing moulding consider key issues related to the technological side and those on the economic side, but also those that are imposed by increasing quality and minimizing environmental impact. Exploring the use of additive manufacturing system based on fundamental data, analyses, measurement and experimental results the scope of this article. This analysis leads to the idea of perspective as moulding materials processing has the potential to become a driving force to achieve a sustainable society by introducing efficient production practices that contribute to a considerable decrease negative environmental impact.

 

Keywords: casting materials processing, technological, development, new procedures

Cuvinte cheie: materiale de turnare de prelucrare, tehnologice, dezvoltare, proceduri noi

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32-44 ANALIZA CHIMICĂ ȘI MICROSTRUCTURALĂ A MATERIALULUI UTILIZAT LA TURNAREA UNUI CLOPOT

Această intrare a fost publicată în 2017 Volumul 32 și etichetată Gabriel BATIN George ARGHIR Liviu BRÂNDUŞAN la de

CHEMICAL AND MICROSTRUCTURAL ANALYSES OF

A MATERIAL USED TO CAST A BELL

 

The present study was setup to determine the chemical composition of a bell material. After 27 years of service, a bell weighting 200 kg was broken. Two solutions were proposed for the repairing: soldering using Ag (cheap, but affecting the sound quality and mechanical properties) and a melting the old bell and casting a new one (approximately 16 times more expensive, but with better properties).  An optical microscope Olympus GX51 was used to study the microstructure. The chemical composition was determined using an XRF device Olympus Delta Element. The analysis showed the presence of lead and tin in composition, close to the upper limits. The presence of lead and eutectic structure, and the porosity produced a large crack on the basis of the bell. Clusters of macro pores were observed near the surface of the bell.  The fatigue could appear on the base of this

 

Keywords: bronze, microstructure, bell material, chemical composition

Cuvinte cheie: bronz, microstructură, material de clopot, compoziție chimică

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32-43 DISPOZITIV DE RECTIFICAT SUPRAFEŢE ELICOIDALE LA SCULE AŞCHIETOARE ADAPTABIL PE MAŞINI DE RECTIFICAT PLAN CARE ARE LA BAZĂ O CUPLĂ CINEMATICĂ DE TIP ROLĂ-CILINDRU

Această intrare a fost publicată în 2017 Volumul 32 și etichetată Alexandru-Cătǎlin MICACIU Ioan-Gheorghe VUŞCAN la de

DEVICE FOR CUTTING TOOLS TO ADJUSTED HELICAL SURFACES OF MILLING CUTTERS TO ADAPT AT  PLANE GRINDING MACHINE WHICH iS BASED ON A COUPLING KINEMATIC ROLL- CYLINDER

 

The paper presents a device for cutting tools to adjusted helical surface of milling cutters to adapt at plane grinding machine.

 

Keywords: helical surfaces clearance tooling

Cuvinte cheie: suprafeţe elicoidale de degajare la scule

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32-24 PROIECTAREA UNEI SUPRAFEȚE POMICOLE DE PRUNI ÎN SISTEM SUPERINTENSIV

Această intrare a fost publicată în 2017 Volumul 32 și etichetată Vlad-Mihai DINU la de

THE PLUM TREE SURFACE DESIGNING

IN A SUPER-INTENSIVE SYSTEM

 

This project presents some of the benefits of a super-intensive plum orchard, a way to access European funding for technology or equipment and steps to be followed for a productive establishment

 

Keywords: plum orchard, founding, technology, importance

Cuvinte cheie: livadă de pruni, finanțare europeană, tehnologie, importanţă

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32-42 DETERMINAREA STABILITĂŢII STATICE A CUPLEI CINEMATICE EXTERIOARE CILINDRU-CILINDRU

Această intrare a fost publicată în 2017 Volumul 32 și etichetată Alexandru-Cătǎlin MICACIU la de

DETERMINATION OF KINEMATIC COUPLING

STATIC OUTER CYLINDER

 

Helicoidally cylindrical surfaces are used for releasing surfaces of cutting tools the paper present aspects about experimental research of the kinematic coupling using different loads and different contact angle between roll and cylinder using a special developed for generation of the helical surfaces

 

Keywords: helical motion, contact pressure, contact angle

Cuvinte cheie: mișcare elicoidală, presiunea de contact, unghi de contact

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32-41 STUDIUL EROZIUNII OȚELULUI USt 37-2 PRIN CAVITAȚIE VIBRATOARE

Această intrare a fost publicată în 2017 Volumul 32 și etichetată Eduard RIEMSCHNEIDER Ilare BORDEAŞU Lavinia Mădălina MICU Liviu Daniel PÎRVULESCU Rodica BĂDĂRĂU Traian BENA la de

Erosion study of the Steel UST 37-2

by vibratory cavitation

 

The paper presents the results of the experiment cavitation vibrators, carried on carbon steel for general use UST 37-2, used in the manufacture of hydraulic turbine components, along the route of water flow into the turbine. Testing is performed on standard crystal vibrator device piezo ceramic of the Cavitation Laboratory of the University Politehnica Timisoara. OH12NDL comparison with standard steel and grey iron with pearlite structure shows that steel has low resistance to cavitation generated by the vibrator device, therefore not recommended in the manufacture of parts in areas of developed cavitation.                    Keywords: erosion, cavitation, carbon steel, average depth of erosion, erosion rate, vibrator device                   Cuvinte cheie: eroziune, cavitație, oțel carbon, adâncime medie de eroziune, viteza de eroziune, aparat vibrator

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32-40 METODE EXPERIMENTALE PENTRU DETERMINAREA REZISTENȚEI LA EROZIUNE ABRAZIVĂ A MATERIALELOR FOLOSITE ÎN FABRICAȚIA MAȘINILOR HIDRAULICE

Această intrare a fost publicată în 2017 Volumul 32 și etichetată Brândușa GHIBAN Carmen-Anca SAFTA Elena Crina CRÎNGAȘU la de

EXPERIMENTAL METHODS FOR TESTING OF THE ABRASIVE EROSION RESISTANT MATERIALS USED IN HYDRAULIC MACHINES MANUFACTURING

 

In the paper are reviewed the known methods applied to test the resistance of a metalic material to abrasive erosion with application to hydraulic machines espacially hydraulic pumps. Are mentioned the methods in the conformity with international standards. Article highlights the method which can be used to test and to measure the abrasive resistance of the materials used in the manufacturing of a hydraulic machine.

 

Keywords: abrasion erosion, test, wear

Cuvinte cheie: eroziune abrazivă, încercare, uzură

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32-39 STADIUL ACTUAL AL TRATAMENTELOR SUPERFICIALE CU RADIAŢII ELECTROMAGNETICE ŞI POSIBILITĂŢI DE EXTINDERE A ARIEI DE APLICABILITATE

Această intrare a fost publicată în 2017 Volumul 32 și etichetată Ioan VIRCA la de

surface treatment on the current state

of electromagnetic radiation and

opportunities for expansion scope

 

In the presents paper the author analyses the current state of superficial treatments with electromagnetic fields, in terms of the purpose and role within the manufacturing processes of parts and ways of energy generation and transmission parts to the surface. The author presents a technological solution suite which consists in the use of gas discharge lamps what emitting pulses of optical radiation for the surface treatment of parts. This solution thus extend the surface treatments with electromagnetic fields, constituting an alternative technology that are of interest to local selective surface hardening of machine parts and for the formation of protective film, cleaning and polishing surfaces.

 

Keywords: surface treatment, electromagnetic radiation, optical radiation pulses, gas discharge lamps, hardening surface

Cuvinte cheie: tratament de suprafață, radiații electromagnetice, pulsuri de radiații optice, lămpi cu descărcare de gaz, suprafață de întărire

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32-38 STAREA DE TENSIUNI ȘI DEFORMAȚII LA PERFORAREA ȚAGLELOR PENTRU ȚEVI FĂRĂ SUDURĂ

Această intrare a fost publicată în 2017 Volumul 32 și etichetată Daniela MILOŞTEAN Ioan ILCA Miruna MAGAON la de

TENSION AND DEFORMATION state at billet perforation for seamless pipes

 

The paper analyses the particularities of perforation through helical rolling of filled billets to achieve blanks for seamless pipes. Also, clarify the plastic flow phenomenon caused by the stress and strain state, which determine the formation of the cavity.

 

Keywords: rolling helical cylinder bitronconic cavity, blanks, seamless, tubes (laminate tubes)

Cuvinte cheie: laminare elicoidală, cilindri bitronconici, cavitate, eboșe, țevi fără sudură (țevi laminate)

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32-37 CONTACTE ELECTRICE CU DENSITATE RIDICATĂ PENTRU CURENŢI INTENŞI PRODUSE PRIN METALURGIA PULBERILOR

Această intrare a fost publicată în 2017 Volumul 32 și etichetată Adrian ARDUSĂTAN Alina Georgeta JUMOLEA George ARGHIR Ioan PETEAN Liviu BRÂNDUŞAN Marius BĂRĂIAN Gabriel BATIN Nicu Marian TRANDAFIR la de

ELECTRICAL CONTACTS WITH HIGH DENSITY FOR STRONG CURRENTS, MADE BY POWDER METALLURGY

 

Electrical contacts for strong currents by infiltration after sintering, was not satisfactory because the final density is much higher (11,100 kg/m3) and porosity is much lower (10.85 %). The infiltration after sintering contains: powder mixture preparation (W – 52 mass %, Ni – 2 %, Cu – 46 %, zinc stearate – 0,7 %  – 7 g), homogenization, pressing (4,5 MPa), sintering (730 and 780 oC). The green density is almost constant, with an identical porosity of the first after the end of the process (14,28 %). By infiltration the density increased drastically (10,832 kg/m3), its variations were increased also and porosity decreased (at 10.85 %). The attained density is not sufficient for electrical contacts work (11,100 kg/m3), but it is closer. Way to improve density: pressing, sintering, and repressing (10,700 kg/m3).

 

Keywords: sintered electrical contacts, W-Cu

Cuvinte cheie: contacte electrice sinterizate, W-Cu

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32-36 FINISAREA EBOȘELOR PENTRU ȚEVI DESTINATE INDUSTRIEI PETROLIERE

Această intrare a fost publicată în 2017 Volumul 32 și etichetată Daniela MILOŞTEAN Ioan ILCA Miruna MAGAON la de

finising blanks for pipes intended to oil industry

 

The paper analyses the Mannesmann process of blanks rolling into pipes of a certain wall thickness and diameter. Also, is focuses on pipes finishing in the size range of 400-900 mm for the exterior diameter, used for gas and petroleum products transportation.

 

Keywords: rough pipes, rolled widening, rolling on the cork, mill Smoothing, rolled pipes

Cuvinte cheie: eboșe pentru țevi, laminare de lărgire, laminare pe dop, laminor netezitor, laminare țevi

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32-35 BRAZARE NICHEL-ALUMINIU

Această intrare a fost publicată în 2017 Volumul 32 și etichetată George ARGHIR Liviu BRÂNDUŞAN Nicu Marian TRANDAFIR la de

BRAZING OF NICKEL-ALUMINIUM

 

The brazing between nickel and aluminium plates is a very sensible process being influenced by type of used materials and by brazing devices which maintain in contact the metal plates. These brazing devices have a very important purpose, their pressure affect directly the capillarity force. If the brazing devices are too tight (like 7 bar pressure), the filler melted metal escape from the grip, causing presence of defects in the joint; if the brazing devices are not tight enough (like 5 bar pressure) the capillarity forces become weak, allowing the voids inside the joint. Therefore, it’ is optimal for a nickel-aluminium brazed joint without defects a 6 bar pressure, created by brazing devices,

 

Keywords: brazing, Ni-Al

Cuvinte cheie: brazare, Ni-Al

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32-34 CERCETĂRI ŞI EXPERIMENTĂRI PRIVIND OPTIMIZAREA REGIMULUI DE SUDARE CU ARC ELECTRIC PENTRU COMPONENTE DIN TABLĂ CU METODA GRADIENTULUI

Această intrare a fost publicată în 2017 Volumul 32 și etichetată Cornel HAŢIEGAN Lenuţa CÎNDEA Octavian BARBU la de

RESEARCH AND EXPERIMENTATION ON OPTMIZING REGIME FOR WELDING COMPONENTS WITH

GRADIENT METHOD

 

The paper presents the calculation algorithm and the optimal solution calculated gradient method, an experimental program conducted on board the components of arc welding in the environment of protective gases. Welding regime parameters on variation conclusions have been drawn, then the gradient method was chosen optimum welding regime.

 

Keywords: welding duty, experimental program, algorithm, gradient method, optimization

Cuvinte cheie: regim de sudare, program experimental, algoritm, metoda gradientului, optimizare

 

32-33 STUDIU PRIVIND DEZVOLTAREA ÎN REŢEA A UNUI PRODUS NOU ÎN DOMENIUL SCULELOR AŞCHIETOARE

Această intrare a fost publicată în 2017 Volumul 32 și etichetată Gina-Maria MORARU Liliana Georgeta POPESCU la de

STUDY ON DEVELOPING IN NETWORK OF A NEW PRODUCT IN CUTTING TOOLS FIELD

 

This study describes patterns of a flexible working structure that allow researchers to react quickly to the environment, to move towards the market, to meet the needs of citizens, to assimilate and process new information in a timely manner, to be innovative and find new solutions. Designing and running a project from an idea, theme, until the prototype imposes complex requirements of the project team in general and project director/project manager – in particular.

 

Keywords: cutting tool, product

Cuvinte cheie: scule aşchietoare, produs

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32-32 PROIECTAREA UNUI DISPOZITIV DE PRINDERE COMPLIANT PENTRU PIESE CU FIXARE ÎN DOUĂ PUNCTE

Această intrare a fost publicată în 2017 Volumul 32 și etichetată Daniel LATEȘ Marius CĂȘVEAN la de

DESIGN OF A COMPLIANT GRIPPING DEVICE FOR

TWO POINTS FIXING PARTS

 

Based on the structure of a technological device with applicability in mini and micro parts manufacturing industry, will present the transformation of a conventional mechanism into a compliant device. First part of the paper will bring in front the main notions from the technological device field, later on the description and the design of a compliant gripping device. This paper will continue with the simulation, device analysis and finally some conclusions to be made and future directions of the research.

 

Keywords: technological device, compliant mechanism, design, simulation

Cuvinte cheie: dispozitiv tehnologic, mecanism compatibil, proiectare, simulare

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32-31 TEHNOLOGIA DE VERIFICARE A CALITǍŢII ANGRENǍRII ÎN ANGRENAJELE MELC-ROATĂ PLANĂ CU CONTACT LOCALIZAT

Această intrare a fost publicată în 2017 Volumul 32 și etichetată Ileana-Dacia NAPĂU Ioan NAPĂU Mircea NAPĂU Radu NAPĂU-STOICA la de

GEAR MESH QUALITY VERIFICATION TECHNOLOGY

OF WORM-FACE GEAR DRIVES WITH LOCALIZED CONTACT

 

Current paper refers generally to the mesh quality verification technology of worm-face gear drives with localized contact, specifically investigating gear drives kinematic precission, as well as teeth contact pattern, as practical methods of evaluation of their quality in exploitation. Experimental results, related to this technology are illustrated through  practical examples, for some particular gear drives, subject of this investigation.

 

Keywords: worm-gear wheel contact plane with localized control kinematic precision control footprint

Cuvinte cheie: angrenaj melc-roată plană cu contact localizat, controlul preciziei cinematice, controlul petei de contact

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32-30 PRECIZIA MAȘINILOR UNELTE DE DEBITARE CU LASER

Această intrare a fost publicată în 2017 Volumul 32 și etichetată Cristina BIRIŞ la de

THE PRECISION OF CNC LASER CUTTING MACHINES

 

This paper present the results of theoretical researches by simulation with regard to the means to optimise the dynamic behaviour of a CNC laser cutting machines, and especially of the components of the kinematic feed chain in terms of cutting precision. The simulation results are presented both for the case of absence and for the case of the presence of technological forces as disturbance factors.

 

Key words: error, precision, numerical control

Cuvinte cheie: eroare, de precizie, cu comandă numerică

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32-29 OPERAREA MAȘINILOR-UNELTE CU COMANDĂ NUMERICĂ. ERORI DE PROGRAMARE

Această intrare a fost publicată în 2017 Volumul 32 și etichetată Dorin SCÂNTEIE la de

NC MACHINE TOOLS OPERATION.

PROGRAMMING ERROR

 

This paper appeared as a necessity, so should students who want to learn how to operate the CNC lathe and CNC milling machine. Training is performed using a program „Soft Swan” (a trial version), which we call simulator. Simulator has an interface composed of elements compatible Windows and virtual image of the machine (lathe or milling machine). The paper presents two common errors due haste, inattention and \ or inexperience.

 

Keywords: simulation, virtual image management tools, tool offset

Cuvinte cheie: simulator, imagine virtuală, managementul sculelor, ofset de sculă

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32-28 PROGRAMAREA G-CODE A UNUI PROIECT 3D

Această intrare a fost publicată în 2017 Volumul 32 și etichetată Cornelia Victoria ANGHEL DRUGĂRIN la de

G-CODE PROGRAMMING FOR 3D

COMPUTER AIDED DESIGN

 

The present work, describe a G-Code programming for a 3D Computer Aided Design. The main program contains four sets of programs, written in chronological order, needed of piece processing operations. The case study proposes in this paper show that through a dedicated software ArtCAM package, we can wood surface from 2D to 3D. G-Code Program contains all operations to engraving by milling the selected text wooden on the plate.

 

Keywords: Computer Numerically Controlled (CNC), G-Code programming language (RS-274), Computer Aided Design, ArtCAM project

Cuvinte cheie: mașini-unelte cu comandă numerică, limbaj de programare G (RS-274), proiectarea asistată de calculator (CAD), ArtCAM proiect

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32-27 IMPLEMENTAREA METODEI HEIJUNKA ÎN CADRUL UNEI LINII DE PRODUCŢIE

Această intrare a fost publicată în 2017 Volumul 32 și etichetată Achim MUNTEAN Marinela INŢĂ la de

HEIJUNKA METHOD IMPLEMENTATION IN

A PRODUCTION LINE

 

The implementation of modern production systems has become a necessity due to global competition and aims a better response to customer requirements, improve quality, decrease delivery times and costs. This paper aims to implement Heijunka method for increasing the performance of a production process within an automotive company in Sibiu. By implementing the method desired volumes leveling to balance inventories and customer demand.

 

Keywords: method Heijunka, production leveling, demand

Cuvinte cheie: metoda Heijunka, nivelare de producție, cererea

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32-26 CONSIDERAȚII DESPRE PRODUCȚIA DE PORUMB ȘI CALCULUL BILANȚULUI ENERGETIC AL ACESTEI CULTURI

Această intrare a fost publicată în 2017 Volumul 32 și etichetată Alexandru ARDELEAN Ioan Aurel CHERECHEŞ la de

CONSIDERATIONS ON CORN CROP

PRODUCTION AND ENERGETIC EFFICIENCY

 

Current context of energy production, the overall situation of the environment affected by hazardous emissions generated by internal combustion engines and not least prices are favouring cheaper fuel production from renewable sources The first step for obtaining bioethanol is represented by agricultural production. The paper is exploring how the cultivation conditions influence the crop levels and the economic efficiency of a corn crop in order to process it for bioethanol production.

 

Keywords: corn production, total energy production, energetic efficiency, fertilization efficiency

Cuvinte cheie: producția de porumb, producția totală de energie, eficiența energetică, eficiența fertilizării

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32-25 PROIECTAREA UNEI FABRICI DE PANIFICAŢIE

Această intrare a fost publicată în 2017 Volumul 32 și etichetată Alexandru Vlăduţ MOLDOVAN Ioan Aurel CHERECHEŞ la de

DESIGNING A BAKERY PRODUCTS FACTORY

In this project will present its importance and benefits of bread and others bakery products. We chose this theme because the bakery industry occupies a very important place in the food, bread is a staple food in human nutrition.

Keywords: bread, bakery, technology, benefits

Cuvinte cheie: lapte, panificaţie, tehnologie, beneficii

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32-23 VARIABILITATEA ELEMENTELOR MORFOMETRICE A TROFEELOR DE CERB COMUN (Cervus elaphus) DIN BAZINUL HIDROGRAFIC GURGHIU

Această intrare a fost publicată în 2017 Volumul 32 și etichetată Iulia Diana GLIGA Maria-Olivia MOLDOVAN Maxim COROCHII la de

THE VARIABILITY OF MORPHOMETRICAL ELEMENTS FEATURES COMMON DEER TROPHIES IN THE CATCHMENT GURGHIU

 

The stag (Cervus elaphus) is one of the most important species in our hunting ground areas. In the socio-economic context of our country, the common deer populations have a great significance taking into consideration both the financial benefits obtained by practicing hunting and its important niche role in the mountain and pre-mountain ecosystems. In present paper we have studied the variability of the morphometric characters of stag trophy at different ages. In order to achieve the proposed objectives, the carried out study analysed a number of 29 trophies.

The assessment of trophies was made by applying the CIC methodology and by respecting all rigors related to characters measuring and use of tools.

The data were statistically processed by calculating the variance, coefficient of variation and establishing the correlations between the morphometric characters and exposing the regression equations of these correlations.

 

Keywords: Cervus elaphu, variability, trophies of deer, morphometric characters, correlations

Cuvinte cheie: Cerb comun, variabilitate, trofee de cerb, caractere morfometrice, corelații

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32-22 MODIFICĂRILE NIVELULUI DE ENERGIE ALE FIINȚEI UMANE. INFLUENȚE ASUPRA STĂRII PSIHICULUI ȘI A STĂRII DE SĂNĂTATE

Această intrare a fost publicată în 2017 Volumul 32 și etichetată Ioan CURTA Lucian MÂNDREA la de

the MODIFICATION OF THE ENERGY LEVEL

OF THE human being. iNFLUENCES UPON

THE PSYCHIC STATE AND HEALTH

 

The authors intend to study how the human bio-field responds at a nonphysical stimulus. More precisely, what happens when a person, using special techniques, retire the energy from the exterior of the body through the interior, for 2-3 minutes? The authors find out that this procedure was interpreted by the energetic body as an aggression leading to a state near illness. The subject stopped his actions, not to create damages to the entire human being which could eventually require a treatment. A very important observation of the authors is that during the experiment it was noticed a tendency of hysteresis for the human being, phenomenon which the authors decided to study in the future.

 

Keywords: energy, human being, psychic state, health, Bio Well device

Cuvinte cheie: energie, ființa umană, stare psihică, sănătate, aparatul Bio Well

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32-21 FRACTALII – ÎNTRE FILOSOFIE ȘI CERCETAREA MATEMATICĂ. APLICAȚII ÎN MECANICA FLUIDELOR

Această intrare a fost publicată în 2017 Volumul 32 și etichetată Constantin AVĂDANEI la de

FRACTALS – PHILOSOPHY BETWEEN RESEARCH AND MATHEMATICS. APPLICATIONS IN FLUID MECHANICS

 

This paper wants a foray into the world of fractals and how to discover the beauty of pure mathematics and hidden connections that it has with the world around us. Also described Fractal Vision appropriate software with which it enters the fantasy world of fractal geometry.

Keywords: fractals, mathematical modeling graphics, equation, algorithm, chaos, fluid dynamics

Cuvinte cheie: fractali, matematica, modelare grafica, ecuatie, algoritm, haos, dinamica fluidelor

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32-20 PARTICULARITĂȚI CONSTRUCTIVE ALE EJECTOARELOR ÎN CONSTRUCȚIA MOTOARELOR RACHETĂ

Această intrare a fost publicată în 2017 Volumul 32 și etichetată Constantin AVĂDANEI Elena-Bianca AVĂDANEI la de

PARTICULARS OF CONSTRUCTION IN CONSTRUCTION EJECTORS ROCKET MOTORS

 

This paper presents some features of evolutionary parameters on fluid flow through the ejector gas dynamics.

Ejectors are devices with wide applicability gas dynamics in the technical field and especially in the military.

 

Keywords: ejector, gas dynamics parameters, chamber, ejection coefficient, fluid driven, driving fluid, turbulent flow

Cuvinte cheie: ejector, parametri gazodinamici, camera de amestec, coeficient de ejectie, fluid antrenat, fluid de antrenare, curgere turbulentă

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32-19 PARTICULARITĂŢI PRIVIND PERTURBAȚIILE AERODINAMICE ÎN JURUL CORPURILOR SUBŢIRI CARE ZBOARĂ ÎN ATMOSFERĂ

Această intrare a fost publicată în 2017 Volumul 32 și etichetată Constantin AVĂDANEI Maria-Costina AVĂDANEI la de

PARTICULARS RELATING TO SPEED DISTURBANCES AROUND BODIES FLYING THIN ATMOSPHERE

 

               The paper presents a contribution to the aerodynamic body of revolution movement trajectories in the thin atmosphere. As a particular case, the paper refers to flying projectiles and missiles, to customize linarite stationary movements around thin bodies of revolution.

 

Key words: projectile, rocket, potential speeds, Mach number, angle of attack

Cuvinte cheie: proiectil, rachetă, potenţialul vitezelor, numărul Mach, unghi de atac

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32-18 CALCULUL COEFICIENTULUI DE CONTRACȚIE AL UNUI ORIFICIU ȘI REPREZENTAREA GRAFICĂ A REZULTATELOR CU PROGRAMUL SIGMA PLOT

Această intrare a fost publicată în 2017 Volumul 32 și etichetată Lucian MÂNDREA Sanda BUDEA la de

THE CALCULUS OF THE CONTRACTION COEFFICIENT OF AN ORIFICE AND THE GRAPHYCAL RESULTS REPRESENTATION WITH SIGMA PLOT PROGRAMME

 

This paper presents the continuation of the studies from the last two articles presented at the last two Sebeș conferences. The authors used the same numerical method to integrate the Navier-Stokes equations and the presentation is done this time using a Sigma Plot programme. The study is performed with a combination of symmetric and asymmetric orifices at the same Reynolds number. The authors used again the method of finite differences to determine the flow through a tank and through the contracted section of the liquid passing an orifice.

 

Keywords: flow coefficient, current lines, symmetrical orifice, asymmetrical orifice, hydrodynamic spectrum, numerical methods

Cuvinte cheie: coeficient de debit, linii de curent, orificiu simetric, orificiu asimetric, spectru hidrodinamic, metode numerice

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32-17 CONSIDERAȚII HIDRAULICE ÎN PROIECTAREA SCĂRILOR DE PEȘTI

Această intrare a fost publicată în 2017 Volumul 32 și etichetată Carmen-Anca SAFTA Cristina Cătălina PETICĂ la de

HYDRAULIC APPROACH OF FISH LEDDER DESIGN

 

The paper presents the design restrictions of fish ladders mentioned in the literature and highlights through an example of how sizing calculation of these structures taking into account the hydraulic flow regime.

 

Keywords: weir, fish ladder, critical flow regime, Froude number

Cuvinte cheie: deversor, scară de pești, regim critic de curgere, număr Froude

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