BUCKLING ANALYSIS OF THE INDUSTRIAL FACTORY MODEL BY FINITE ELEMENT METHOD

Buckling is a subject that has been discussed for a long time, however, it still be studied and developed due to its practicality. The following article introduces two methods that are used to solve the problems involving buckling of the beam, shell and solid with an I shape cross-section having different cases of boundary load. The theory which is used in this article is Euler's formula and Eurocode 3 standard. The analytical results by ANSYS commercial software are compared with the theoretical results and results from Eurocode 3 standard. The authors based on the reliability of the calculating results to simulate buckling of the industrial factory model with different cases of load conditions. The simulating results show a general view of buckling cases

THE ANALYSIS OF FLUID DYNAMICS OF WAVE POWER STATION WITH WELLS TURBIN BY CFD

Natural energy such as wind, wave and other natural vibrations is one of the high potential renewable energy sources. The Wells turbine is based on the use of bidirectional turbines, which act as axial-flow self-rectifying turbines that employs a symmetrical blade profile and rotating unidirectionally in reciprocating airflows generated by the air chamber to extract energy from vibrations. These topics have been extensively studied both numerically and experimentally such as research on the parameters of the effects of structure, angle of attack, blade shape, etc. In this paper, numerical simulation is carried out using commercially available tool Fluent for fluid dynamics analysis and focus on oscillating predictions, with particular attention to the behavior of the flow. Based on the Numerical Wave Tank (NWT) model is simulated in a two dimensional used in this model, which is constructed mainly based on the spatially averaged Navier Stokes equation with the k-ε model for simulating the turbulence and modeled with Volume of Fluid (VOF). Axial-flow turbines system and future development as well as the proposed limitations will be discussed in detail

An enhanced nodal gradient finite element for non-linear heat transfer analysis

The present work is devoted to the analysis of non-linear heat transfer problems using the recent development of consective-interpolation procedure. Approximation of temperature is enhanced by taking into account both the nodal values and their averaged nodal gradients, which results in an improved finite element model. The novel formulation possesses many desirable properties including higher accuracy and higher-order continuity, without any change of the total number of degrees of freedom. The non-linear heat transfer problems equation is linearized and iteratively solved by the Newton-Raphson scheme. To show the accuracy and efficiency of the proposed method, several numerical examples are hence considered and analyzed

New Species of Orchids (Orchidaceae) in the Flora of Vietnam

This paper summarizes results of joint efforts of professional botanists and orchid enthusiasts on studies of Vietnamese native orchids during years 2013–2016. It provides new original data about the discovery of 1 genus (Grammatophyllum Blume) and 29 orchid species new for the flora of Vietnam. Valid name, main synonyms, data on type, ecology, phenology, estimated IUCN Red List status, distribution, studied specimens, as well as brief taxonomic and biological notes are provided for each species and varieties. Eight species (Bidupia khangii, Bulbophyllum striatulum, B. tipula, Cleisostoma dorsisacculatum, Cymbidium repens, Dendrobium congianum, Flickingeria xanthocheila, Podochilus rotundipetala) and two varieties (Phreatia densiflora var. vietnamensis, P. formosana var. continentalis) are described as new for science. One combination (Bulbophyllum bicolor var. funingense) is proposed. An illustrated annotated list of all studied species and varieties is arranged in alphabetical order. Including present data, the known orchid flora of Vietnam comprises currently at least 1210 documented species from 172 genera