in this paper, direct numerical simulation of two-phase incompressible gas-liquid flow for simulation of bubble motion in a microtube is presented. microtube radius is 10 µm. the interface is tracked using volume of fluid (vof) method with continuous surface force (csf) model. the flow is solved using a finite volume scheme, based on piso algorithm. numerical simulation is performed on a axisym...

Natural convection heat transfer has many applications in different fields of industry; such as cooling industries, electronic transformer devices and ventilation equipment; due to simple process, economic advantage, low noise and renewed retrieval. Recently, heat transfer of nanofluids have been considered because of higher thermal conductivity coefficient compared with those of ordinary fluid...

an ultrafine grained dual phase (ufg dp) steel containing niobium was produced by a new routeutilizing simple cold-rolling and subsequent intercritical annealing of ferrite/martensite duplex startingstructures. the effects of intercritical holding time on the microstructural evolutions and mechanicalproperties were studied. the results showed that increasing intercritical holding time enhnaced ...

The microstructure and properties of a 5 wt.% Cr cold work tool steel were studied after austenitisation at 1020°C, 1050°C or 1075°C followed by single, double and triple tempering treatments at 525°C. The microstructures were investigated with scanning electron microscopy and X-ray diffraction and phase transformations were studied by dilatometry. Furthermore, hardness and Charpy un-notched an...

Annealing process is critical to mechanical properties and microstructure of DP steel. For steel with strength grade 590MPa, experiments different combinations intercritical annealing temperature over-aging were carried out during annealing. The tensile tests the final products nanohardness phases made, microstructures analyzed. results indicated that higher was favorable volume fraction marten...

The background to this bachelor thesis is an on-going project within the VINN Excellence Center Hero-m. The task in this thesis is to perform a literature survey about the martensite transformation and investigate how the resulting fraction depends on cooling below the Ms-temperature. Instead of calculating the undercooling for each of the known fractions of martensite the driving force will be...

Following the mathematical approach of Kelly (2003), rigorous version of infinitesimal deformation approach (ID) was applied to analyze fcc  bcc martensitic phase transformation observed in Fe-31wt Ni alloys considering the twinning shear system as the lattice invariant system (LIS). The expressions for crystallographical parameters associated with the martensitic phase transformation such as...