Nova proposta de critério de retenção para dimensionamento de filtros têxteis

The designs of filters made by granular material or textile are mainly based on empirical or semi empirical retention criteria according to Terzaghi proposal, which compares particle diameter of the soil base with the filter porous spaces. Silveira in 1965, proposed one rational design retention criteria based on the probability of a particle from the soil base, carried by one dimensional flow, be restrained by the porous of the filter while trying to pass through its thickness. This new innovating theory, besides of being very simple, it is not frequently used for granular filters since the necessary parameters for the design has to be determine for each natural material. However, for textile this problem no longer exists because it has quality control during manufacturing and the necessary characteristics properties of the product are specify in the product catalog. This work presents one adaptation of the Silveira theory for textile filters and the step-by-step procedure for the determination of the characteristics properties of the textile products necessary for the design. This new procedure permits the determination of the confiability level of retention that one specific particle diameter form the soil base has for one specified textile. One complete example is presented to demonstrate the simplicity of the method proposed and how the textile characteristics are obtained.

Análise de falhas por fadiga de alto ciclo em eixos de transmissão utilizando o método dos elementos finitos

This work presents a study that aims to validate the fatigue analyses developed on finite element commercial software, ANSYS Workbench. It was based on mechanical tests development of traction and hardness, to verify the mechanical properties of material that the shaft was manufactured (ABNT 1045 steel), it was developed bend test, with purpose to prove the confiability degree of computational analyses, obtaining the maximum stress in a work condition determined with 40 [kgf] of load applied, and at the end, was developed the fatigue test to obtain the number of cycles that the transmission shaft can support in a work condition with 8 [kgf] of load applied. The results obtained during the work present, have to be quite satisfactory with the theoretically expected

Caracterização filogenética de percevejos terrestres das famílias Coreidae e Pentatomidae (Heteroptera: Pentatomomorpha) por meio de marcadores moleculares

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)