Dual phase steels with different martensite volume fraction and morphology were tensile tested at a temperature range of 25 to 5500C. Stress-strain curves of all steels showed serration flow at temperatures of 250 and 3500C, and smooth flow at the other temperatures. Both yield and ultimate tensile strengths increased with increasing testing temperature up to about 450<sup...

In this paper a novel numerical approach is presented for solving the transient incompressible fluid flow problems with free surfaces in generalized two-dimensional curvilinear coordinate systems. Solution algorithm is a combination of implicit real-time steps and explicit pseudo-time steps. Governing fluid flow equations are discretized using a collocated finite-volume mesh. Convective terms a...

One way to increase the heat transfer is to use perforated twisted tapes with different hole diameters, which largely improve heat transfer with an increase in the heat transfer area at the constant volume and more mixed flow. In the previous studies, the effect of nanofluids with perforated twisted tapes is less studied. In this work, the performance of water / iron oxide nanofluid in a double...

Using of nanofluids and ducts with corrugated walls are both supposed to enhance heat transfer, by increasing the heat transfer fluid conductivity and the heat transfer area respectively. Use of a diverging duct with a jet at inlet section may further increase heat transfer by creating recirculation zones inside the duct. In this work two-dimensional incompressible laminar flow of a nanofluid e...

two-dimensional euler equations have been solved on an unstructured grid. an upwind finite volume scheme, based on roes flux difference splitting method, is used to discretize the equations. using advancing front method, an initial delaunay triangulation has been made. the adaptation procedure involves mesh enrichment coarsening in regions of flow with high low gradients of flow properties, acc...

The physiology underlying inspiratory flow has been the subject of study for a long time. In the late 1950s, Hyatt et al did seminal investigations of the pressure, flow, and volume characteristics of the lung.1 In those early days the primary interest in flow-volume curves centered on expiratory flow, what controlled it, and how it was limited in various obstructive lung diseases.2 Even in the...

the numerical method presented by safaiy et al. [1] is reformulated with finite volume method in its most general form and tested on non-orthogonal flow problems. navier-stokes equations are solved for the solution of stream function and vorticity. numerical solutions of the driven skewed cavity flow, solved using a fine grid (513×513) mesh, are presented for reynolds number of 100 and 1000 for...

in this paper, the transient inertial viscoelastic flow around a circular cylinder is investigated numerically. a second order finite-volume method is used to increase the numerical accuracy. here, the giesekus model is used as the constitutive equation. this nonlinear model has prominent ability in describing normal stress differences and viscosity in power-law regions. the impacts of the elas...