in this paper, the flow of couple stress fluid is investigated in a helical screw rheometer (hsr). by unwrapping the channel, lands, and the outside rotating barrel, the geometry of hsr is approximated as a shallow infinite channel. both one- and two-dimensional analysis of the problem is presented using rectangular coordinates. in either case an exact solution of the flow problem is presented ...

using piezoelectric patches the stress concentration around a hole on a plate under tension is reduced and controlled. to attain the reduction in stress two placements for piezoelectric patches is investigated. the first location is top/bottom of the hole with compression induced strain and the second is left/right of the hole with tension induced strains to control the stress flow. the result ...

secondary flow investigation could be regarded as an important issue in open channel flow, in spite of its lower quantity compared to the base flow in the water course. it should be given special consideration because of the influence on some hydraulic factors in open channel, specifically in compound channels. in compound channels' due to the difference in the flow velocity of the main ch...

following the recent work of the authors in development and numerical verification of a new kinematic approach of the limit analysis for surface footings on non-associative materials, a practical procedure is proposed to utilize the theory. it is known that both the peak friction angle and dilation angle depend on the sand density as well as the stress level, which was not the concern of the fo...

nowadays acoustic emission (ae) testing based on the kaiser effect (ke) is increasingly used to estimate the in-situ stress in laboratories. in this work, this effect is assessed on cylindrical specimens in numerical simulations of the cyclic loadings including loading, unloading, and re-loading cycles using a 3d code called the particle flow code (pfc) based upon the distinct element method. t...

percutaneous coronary angioplasty (ptca) of a coronary stenosis without documented ischemia at noninvasive stress testing is often performed, but its benefit is unproven. coronary pressure– derived fractional flow reserve (ffr) is an invasive index of stenosis severity defined as the ratio of maximal blood pressure in a stenotic vessel to the normal maximal pressure in the same vessel. ffr is a...

pavement permanent deformations due to lack of shear strength in mixture are a major reason of rutting. any simple test to determine mixtures resistance to permanent deformation isn’t distinguished in the 1st level of superpave mix design method and prevalent methods for evaluating mixture rut resistance are expensive and time-consuming. two aggregate types, gradations, asphalt cements and fill...

The aim of this paper is to study the effect of slip velocity and shape of stenosis on non-Newtonian flow of blood through a stenosed arterial segment. Blood is modeled as Bingham-Plastic fluid in a uniform circular tube with a radially non-symmetric stenosis. The problem is investigated by a joint effort of analytical and numerical techniques. The influence of stenosis shape parameter, slip ve...