The heat transfer performance of a solar external receiver tube with guide vanes was numerically studied under non-uniform flux conditions. Models the smooth and were built. distributions temperature, velocity, turbulence intensity, Nu predicted by these two models compared to investigate enhancement mixing effect vanes. Re α on also studied. results show that form spiraling flows, reduce maxim...

Abstract Fan systems used to transport fluids are widely and have become a major consumer of electrical energy worldwide. A significant part the available transported air in HVAC has usually been lost (in form dynamic pressure) at system outlet. It is well-known that using outlet diffusers leads this loss be reduced. In some cases, it necessary use shortened wide-angle diffusers, which higher c...

In this paper we first introduce a new multiplication on triangular Banach algebras. Then we study their Arens regularity as well as their topological centers . In this paper we first introduce a new multiplication on triangular Banach algebras. Then we study their Arens regularity as well as their topological centers . In this paper we first introduce a new multiplication on triangular Banach ...

This paper describes the effects of guide vanes installed in curved conduits with main emphasis on pressure loss reduction. In parts conduits, eddy zones are created due to flow separation resulting an increased value drop. Installation can prevent creation large zones. On other hand, cross-section conduit is decreased by placing vanes, leading growth That why properties needed be selected care...

in this century due to population growth, the use of river water has become more complicated. since most rivers pass across loose and erodible areas, they always act as the most important factor of transferring eroded materials from the solid crust of the earth.  vortex basins are among the solutions known for the high-speed separation of solids from liquids (filtration). one of the problems of...

Given a complex matrix H, we consider the decomposition H = QRP∗, where R is upper triangular and Q and P have orthonormal columns. Special instances of this decomposition include the singular value decomposition (SVD) and the Schur decomposition where R is an upper triangular matrix with the eigenvalues of H on the diagonal. We show that any diagonal for R can be achieved that satisfies Weyl’s...

A multistage centrifugal pump is designed for pumping low-viscosity, highly volatile and flammable chemicals, including hydrocarbons, high head requirements. The five-stage consists of a double-suction impeller at the first stage followed by twin volute. impellers stages two through five are single-suction diffuser vanes return channel vanes. analytical performance calculated initially in desig...

For little q-Jacobi polynomials and q-Hahn polynomials we give particular q-hypergeometric series representations in which the termwise q = 0 limit can be taken. When rewritten in matrix form, these series representations can be viewed as LU factorizations. We develop a general theory of LU factorizations related to complete systems of orthogonal polynomials with discrete orthogonality relation...

The central recirculation zone (CRZ) in a swirl stabilized gas turbine combustor has a dominant effect on the fuel air mixing process and flame stability. Most of state of the art swirlers share one disadvantage; the fixed swirl number for the same swirler configuration. Thus, in a mathematical sense, Reynolds number becomes the sole parameter for controlling the flow characteristics inside the...

A new mechanism responsible for structural life consumption due to resonant fatigue in turbine blades, or vanes, is presented and explained. A rotating blade or vane in a gas turbine can change its contour due to erosion and/or material build up, in any of these instances, the surface pressure distribution occurring on the suction and pressure sides of blades-vanes can suffer substantial modifi...