The purpose of this study was to investigate traffic flow characteristics at off-ramp junctions in Iranian expressways. The study was conducted on the traffic behavior in isolated off-ramp vicinity of 6-lane expressways. The database consisted of traffic flow and traffic speed information extracted from videotapes. The relationship between diverging traffic flow in the right lane of expressway ...

The flow behavior around a cam shaped tube in cross flow has been investigated experimentally using flow visualization and pressure distribution measurement. The range of attack angle and Reynolds number based on an equivalent circular diameter are within 0 ≤ α ≤ 360˚ and 2 x 104 < Reeq < 3.4 x 104, respectively. The pressure drag features are clarified in relation to the flow behavior around t...

High speed wind tunnels are widely used in the study of fluid flow behavior around various objects. The air flow in the starting step of supersonic wind tunnels is transient including strong shock waves caused by the interaction of the tunnel main stream and the boundary layer at walls. To arrive in running step, the tunnel must be designed so as these waves leave immediately the test section. ...

A plasticity-fracture constitutive model is presented for prediction of the behavior of confined plain concrete. A three-parameter yield surface is used to define the elastic limit. Volumetric plastic strain is defined as hardening parameter, which together with a nonlinear plastic potential forms a non-associated flow rule. The use of non-associated flow rule improves the prediction of the dil...

the effect of addition of qodumeh shahri (lepidium perfoliatum) seed gum on the emulsion properties were investigated in this study. l. perfoliatum seed gum with 0-0.6% (w/w) concentration was used together with 2% (w/w) wpc to emulsify 20% (w/w) corn oil. the emulsion was analyzed for emulsion stability, particle size, specific surface area, particle size distribution and rheological propertie...

dependence on chemical fertilizer continually is increasing. continual increasing of using chemicalfertilizer causes nature pollution (e.g. water contamination). this has led researchers to aggressively investigate renewable fertilizer resources, biomass, to produce organic crops and reduced wastage. wormy compost is a bulk solid and biomass feed stocks. wormy compost flow is obstacle as it oft...

in this work a numerical study of thermal and fluid dynamics behavior of natural air convection in a square cavity in a laminar flow is presented, by finite volume method. the square cavity has two walls heated with different temperatures and two isolated walls. the numerical simulation is made up of several rayleigh numbers to . flow and isotherm lines are presented and analyzed. the numerical...

a numerical framework has been proposed to model the interacting effects of mixture non-ideality and mass transfer on hydrodynamics of a multiphase system using cfd methods.mass transfer during condensation and vaporization is modeled by chemical potential at the liquid-vapor interface. species mass transfers are related to the diffusion at the interface which in turn is related to the concentr...

The hot compression tests were carried on X45CrNiW189 valve steel (X45) in the temperature range of 1000– 1200 °C and the strain rate range of 0.004 – 0.5 s-1 in order to study the high temperature softening behavior of this steel. For the exact prediction of flow stress, the effective stress-effective strain curves were obtained from experiments under various conditions. On the basis of experi...