Spacer grids along the fuel assembly of Pressurized Water Reactors (PWR) maintain rod bundles arranged in a regular square configuration. The mixing vanes present in the spacer grids promote cross and swirl flow between and within the subchannels, enhancing the heat transfer performance in the grid vicinity, but also causing an adverse increase of the pressure drop in the rod bundle due the con...

The geometry of feather barbs (barb length and barb angle) determines feather vane asymmetry and vane rigidity, which are both critical to a feather's aerodynamic performance. Here, we describe the relationship between barb geometry and aerodynamic function across the evolutionary history of asymmetrical flight feathers, from Mesozoic taxa outside of modern avian diversity (Microraptor, Archaeo...

flow passing through lateral intakes and channel junctions is turbulent. sediment flow and bed forms areaffected by these flow patterns and vice versa. in this research, a laboratory study was carried out toexplore a possible method for sediment control for a set of submerged vanes and a single spur dikesimultaneously. since a larger portion of the near-bed flow was diverted, the intake receive...

Abstract This paper presents experimental and numerical CFD studies of the aerodynamics a turbine rear structure (TRS). The TRS test geometry is an engine-realistic state-of-the-art design with polygonal outer case, recessed engine mount bumps, three different vane types: regular vanes, bump vanes in sectors, thick vanes. Using sector types simultaneously was found to be crucial for inlet bound...

Scour is one of the main causes hydraulic structural failures. The present experimental study examines use riprap, submerged vanes, and a combination these for scour reduction around vertical walls spill-through abutments under clear-water conditions. Specifically, influence placing riprap stones with different apron shapes (geometry) and/or group vanes constant height length on abutment was ex...

in this paper, we investigate the existence of a positive solution of fully fuzzy linear equation systems. this paper mainly to discuss a new decomposition of a nonsingular fuzzy matrix, the symmetric times triangular (st) decomposition. by this decomposition, every nonsingular fuzzy matrix can be represented as a product of a fuzzy symmetric matrix s and a fuzzy triangular matrix t.

jahanshahloo has suggested a method for the solving linear programming problems with zero-one variables‎. ‎in this paper we formulate fully fuzzy linear programming problems with zero-one variables and a method for solving these problems is presented using the ranking function and also the branch and bound method along with an example is presented.