Abstract The parameters such as oil density and bulk elastic modulus of hydraulic in steam turbine electro-hydraulic servo system vary with ambient temperature, pressure, other factors, there are unmodeled dynamics the system, so obtaining a satisfactory following effect is challenging task for servo(EHS) system. According to principle force balance flow continuity, mathematical model bilateral...

This paper presents the numerical elastic solution for a real problem, functionally graded chamber of hydraulic gear pumps under internal pressure. Because of the similarity and complexity for the considering geometry, a bipolar cylindrical coordinate system is used to extract the governing equations. The material properties are considered to vary along the two tangled circles with a power-law ...

ABSTRACTRenewable Energy Sources (RES) are well – defined as energy sources, that are in abundance within the natural surroundings and are much inexhaustible. In addition, hydroelectricity (HE) is a vital part of world renewable energy supply and hydropower remains a bulk source of electricity generation because of its environmental friendliness in nature. Modeling is the analysis of the ...

We examined how substrate and complex hydraulic variables limit the distribution of freshwater mussels. We sampled mussels and measured substrate and hydraulic variables (at low and high flows) at 6 sites in the Little River, Oklahoma. To test which variables were most limiting to mussel species richness and abundance, we evaluated univariate and multiple 95-, 90-, and 85-quantile regression mo...

A variational formulation has been developed to solve a parabolic partial differential equation describing free-surface flows in a porous medium. The variational finite element method is used to obtain a discrete form of equations for a two-dimensional domain. The matrix characteristics and the stability criteria have been investigated to develop a stable numerical algorithm for solving the gov...