in this paper, convection heat transfer of al2o3-water nanofluid turbulent flow through internally ribbed tubes with different rib shapes (rectangular, trapezoidal and semi-circular) is numerically investigated. for each rib shape, the optimum geometric ratio and volume fraction were calculated using entropy generation minimization technique. the governing equations in steady state and axisymme...

Abstract The paper presents the solution of conjugated heat exchange problem in a cylindrical ribbed tube using open integrated platform OpenFOAM. obtained results allow estimating fluid heating along channel as well temperature difference on walls tube. It is shown that minimum observed center tube, and maximum one closer to walls.

this paper presents a three-dimensional numerical investigation carried out in turbulent forced convection in a tube with helical ribs. enhancement of heat transfer using helically corrugated tubes has beenstudied experimentally by many researchers but there exist a few published numerical analyses results. the paper also introduces the results of heat transfer and friction factor data for inco...

Controversial views have been expressed about whether tarantula feet can secrete fine silk threads that could prevent them from falling off smooth vertical surfaces. Two studies have claimed that 'ribbed hairs' on the tarsi of tarantulas produce silk. We examined these ribbed hairs in several tarantula species using light and scanning electron microscopy, and compared them with the silk-produci...

Multi-ribbed frame grid (hereinafter referred to as MRFG) is an important part of Multi-ribbed composite wall and consisted of outer frame and ribbed grid. The reinforcement of outer frame is the main influence factor on the performance of MRFG. In this study, an MRFG specimen under laterally cyclic and axial loading in literature is numerically simulated with 5 kinds of different reinforcement...

In order to study the basic mechanical property of cast-in-place stiffening-ribbed-hollow-pipe reinforced concrete girderless floor, and similarities and differences of the structural performance compared with traditional floor, we carried out the destructive stage loading test on the short-term load test of floor model with four clamped edges supported in large scale, and conducted the long-te...

According to the actual working conditions of the Vribbed belt, automobile V-ribbed belt fatigue tester machine is designed to test for the automobile engine Vribbed belt fatigue wear. Finite-element analysis software ANSYS is employed to perform finite-element analysis on fatigue testing machine load shaft, bearing, universal joint key parts of the finite-element analysis, and to analyze the m...

Plates reinforced by ribs or joists are common elements in lightweight building structures, as well as in other engineering structures. However, these structures are not well suited for the common simplified prediction models such as Statistical Energy Analysis (SEA) or the European calculation standard EN 12354. There are several reasons for this: One is that the overall vibration field is not...

A weighted sum of spatial gradients (WSSG) control metric for use in active structural acoustic control of finite ribbed plates was developed and compared to volume velocity. A finite element model was used to obtain the displacement field on the plate, and a finite difference derivative approach to obtaining the terms in WSSG was used. Previous results of ASAC on finite ribbed plates are minim...