Some Aspects Regarding the Elaboration of Multiple Precessional Gear Theory and Modern Manufacturing Technology

The engineering complex study of the triad “gear-technology-transmission” has permitted to elaborate a new type of precessional transmissions with multicouple gear. In this paper, the authors present the mathematic model of the multicouple gear. A computer program for doing this it is also elaborated. It is shown a blockscheme of the algorithm of the program modules including the calculus modalities exposed in the paper

Bioavailability of nutrients associated with sediment and suspension of the Danube Delta : assessment by algal bioassays

Comme centre de biodiversité, le Delta du Danube se trouve parmi les sites naturels les plus importants d'Europe. De nos jours, le processus d'eutrophisation est un des grands fléaux qui touchent les environnements aquatiques. Les nutriments qui sont à la base de ce processus se trouvent dans les systèmes aquatiques sous forme dissoute et particulaire. Cette recherche s'est penchée principalement sur les nutriments associés au matériel particulaire présent dans le Delta du Danube. Les résultats montrent que le Danube transporte des quantités importantes de nutriments sous forme particulaire (20% de phosphore biodisponible apporté par le Danube dans le delta se trouve sous cette forme), avec des concentrations relativement élevées par rapport à d'autres rivières européennes. Les nutriments associés aux particules (suspensions et sédiments du fond des lacs) peuvent constituer une source importante pour la production primaire dans le Delta du Danube. Leur remobilisation et leur biodisponibilité potentielle ont été démontrées par ce travail

CAE DEVELOPMENT OF PRECESSIONAL DRIVES USING AUTODESK INVENTOR PLATFORM

The paper presents the modelling and simulation of precessional drives designed in two variants capable of high transmission ratio and torque for one stage compact construction. The constructions were designed in Inventor and also as multi body systems in otionInventor. The simulations of the drives provide information concerning positions, velocities, accelerations, point trajectories, forces and moments, energies, as well as contact forces at the contact between gear teeth and satellite teeth and other data concerning the system

THE ECONOMIC IMPACT OF RELIGIOUS TOURISM ON THE NORTH EAST REGION OF ROMANIA

Abstract Every people have its own original place within universal culture. Nations must be able to take advantage of existent cultural potential and, if possible, to convert it into a source of development. From this perspective we admit that Romania possesses the privilege of some cultural peculiarities able to sustain positive economic dynamics. The outstanding historical and religious patrimony, prevailing in the North-East region of the country, most of it part of the UNESCO heritage, serve as clear evidence. Even so, all these native "resources" have been insufficiently explored in order to acquire growth and economic development. Exploited with efficiency, the ecumenical vestiges might become an important source of regional prosperity, so the aim of the paper is to emphasize the remarkable potential of religious tourism in North-East Romania and moreover, its notable contribution to regional development prospects

Method of axial adjustment for precessional transmissions

Axial adjustment method for precessional transmissions includes compensation error calculation, determination compensator groups, achieved in the form of base and auxiliary rings. The compensator has on the base ring axial canals in which can be placed clamping bolts but the auxiliary ring has axial holes for the screws. The auxiliary ring is formed from increasing sectors - the distance between auxiliary ring stairs and front side of body, from decreasing sectors - the distance between base ring and bottom place, and the closure element - the clearance between gear body and the front surface of the base ring. According to the method of group interchangeability is determined the deviation value of the upper and lower group tolerance and the clearance between lid and body. Then rotating one of the rings is ensured the dimension of the compensator which must match to compensation clearance value and then the compensator is adjusted to required value

Resilient Energy Systems: Renewables: Wind, Solar, Hydro

Renewable energy systems are playing an important role in the current discourse on energy security and sustainability. Scientific, engineering and economic solutions are adopted, and there is a constant effort to understand mechanisms and options to allow a faster penetration of renewable systems in the current energy mix and energy market. Readers of this book will have access to information, engineering design and economic solutions for harvesting local and regional energy potential by means of solar, wind, hydro resources…. [From Amazon.com]https://digitalcommons.odu.edu/emse_books/1004/thumbnail.jp

THEORETICAL CONTRIBUTIONS ON THE SELECTION OF POSSIBLE TRIBOLOGICAL COUPLES OF MATERIALS FOR THE MANUFACTURE OF PRECESSIONAL TRANSMISSIONS

Selecting gear materials is a great challenge for engineers. Gear teeth are subject to difficult and severe loading conditions. Simultaneous action of alternating normal and tangential dynamic stresses occurs, contact deformations accompanied by sliding friction. Gears are subject to increased requirements in terms of strength, geometric accuracy, dimensional stability, and durability. For the manufacture of gears, especially from thermoplastic materials, a theoretical argumentation of the materials is needed. An extensive study of thermoplastic materials, around the world needs to be done and the most efficient tribological couples to be chosen in terms of heat transfer from the gear zone, operation with or without lubrication, and gear life. In this paper, a theoretical synthesis of the Steel / Plastic, Plastic / Plastic, Plastic/Steel tribological couples is made, which were used in conformist and non-conformist experiments. Therefore, selected tribological couples are supposed to be used in the Precessional Transmissions applications

Resilient Energy SystemsRenewables: Wind, Solar, Hydro /

VIII, 507 p. 424 illus., 330 illus. in color.onli

THEORETICAL AND EXPERIMENTAL MODELLING OF THE TRIBOLOGICAL BEHAVIOUR ASPECTS OF CONTACT ELEMENTS IN THE PRECESSIONAL GEARING (PG)

This paper deals with the theoretical-experimental model of the tribological behavior of the contact elements in precessional gears (PG) in the functions of conjugate profiles of linear velocities "convex-concave" or "convex-convex" for the corresponding geometric parameters (ρk i k ρ − r) and the values of the kinematic force parameters (VE 2 , VE i Va) for each concrete position of the ki points. The calculation of the constructivefunctional and kinematic parameters of the “roller-shoe” and “roller-roller” elements of the tribocouple were adjusted for the experimental verification tests on the SMT-1 installation and adapted to the specific test conditions of the tribocouples with conformal contact of gear teeth made of plastics, which will be subjected to sliding friction and rolling processes of the concrete tribocouple elements