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...

An analytical model of vane dynamics in a tilted vane rotary compressor is presented. With the geometric relationship of the vane in a tilted slot, and the roller, the kinetic equations were derived for evaluating the reciprocating inertial force of the vane, and the chamber volume equations were obtained for calculating pressure history inside the compression chamber. The empirical friction co...

This laboratory study focused on the effect of a submerged vane-field flow pattern and bed morphology near inside entrance reach movable 90° lateral diversion. The system was modelled under live conditions for water discharge ratio ?0.2. Two experiments were run until equilibrium reached: with without installed close to diversion control transfer sediments into channel. associated 3D field meas...

This study presents effects of the vane spring stiffness on frictional power characteristics of a refrigeration compressor. Comparisons on the compressor performance are investigated for different vane spring stiffnesses with compressors designed with high and low shell pressures. Results show that while compressors with a low shell pressure using a higher spring stiffness combination may reduc...

The reason for the abnormal wear between the vane-slot and the vane in the rotary compressor is analyzed in this paper. Firstly, the influence of lubrication at the clearance, the machining equipment accuracy and oil circulation (oil flow rate) is analyzed. Then the material characteristics including the hardness of the vane and vane-slot, the surface treatment of the vane and the deformation o...

The effects of the diffuser vane on the performances of the multistage centrifugal pump were investigated experimentally, taking account of the interactions among the diffuser vane, the return vane, and the next stage impeller. It is very important to match well the diffuser vane with the return vane, for improving the hydraulic efficiency of the pump. The efficiency may be more improved by mak...

Asymmetry in flight feather vane width is a major functional innovation associated with the evolution of flight in the ancestors of birds. However, the developmental and morphological basis of feather shape is not simple, and the developmental processes involved in vane width asymmetry are poorly understood. We present a theoretical model of feather morphology and development that describes the...

In this study, in order to investigate the lubrication characteristics of the sliding surface of the vane in a rotary compressor, numerical analysis for mixed lubrication has been developed. In this analysis, the modified Reynolds equation and the elastic contact equation, considering the surface roughness, are solved as a coupled problem. Using this analysis, the lubrication characteristics of...

The results from two numerical simulations of the unsteady flow in a 1-1/2 stage axial-flow turbine are presented and compared with experimental data to show both the effect of blade count on the solution accuracy and the time-averaged and unsteady flow physics present. The TFLO three-dimensional, multi-block, massively parallel turbomachinery flow solution procedure is used to simulate the flo...

A simple analytical model is developed for the design of a particular compressor vane-spring in this paper. The model permits the calculation of the stresses due to both static and fatigue loads, and also checks for possible material failure. In addition, a :finite element analysis, using a commercially available finite element method (FEM) computer software, was carried out to determine the sp...