in this study, the effect of the levels of hydrogen addition to methane-air premixed flame in a micro-stepped reactor has been studied numerically. in addition, the effects of mixture velocity and walls’ thermal conductivity (kw) on the flame’s location, temperature, and species distribution in a micro reactor were calculated using a 2d numerical laminar steady code. the results showed that an ...

The present study considers of the water and air flow and Micro-Bubble production inside the venturi tube, by the use of dimensional analysis. Numerical analysis of Micro-Bubble creation in venturi tube requires fast computers and large amounts of storage space. Up to now, there has been no numerical analysis concerning Micro-Bubble creation and all other existing studies are experimental. To s...

In this study, electro-thermo-mechanical nonlinear vibration and instability of embedded piezoelectric micro-tube is carried out based on nonlocal theory and nonlinear Donnell's shell model. The smart micro-tube made of Poly-vinylidene fluoride (PVDF) is conveying an isentropic, incompressible fluid. The detailed parametric study is conducted, focusing on the remarkable effects of mean flow vel...

In present work, comparison of three different tube bundles for particular heat exchanger is proposed. Three types are smooth, micro finned and corrugated tubes. Heat exchanger will be designed with smooth tube bundle and simulated. Micro fin and corrugation over tube is applied separately for same heat exchanger in feasible size and simulated for performance. Besides, comparison is done with h...

in this study, fluid flow and energy separation in a micro-scale ranque-hilschvortex tube are numerically investigated. the flow is assumed as 2d, steady,compressible ideal gas, and shear-stress-transport sst k-w is found to be a bestchoice for modeling of turbulence phenomena. the results are in a good agreementwith the experimental results reported in the literature. the results show that flu...

introduction: erythrocyte sedimentation rate (esr) remains as one of the most reliable tests in clinical practices. yet its use is time consuming and requires a large blood sample. the aim of this study was assessing a faster and reliable method of esr estimation. methods: an esr estimation method was described and performed on 108 patients using capillary tube (micro esr) and capillary periphe...

in this study, selenium was recovered from an industrial dust. after the purification process, the researchers were able to prepare selenium micro powder. the objective of this study was to prepare selenium nano particles by water solution phase method from the micro powders. the results showed that selenium micronized powder and nano particles had high purity. the obtained nanoparticles were t...

The combustion characteristics of methane/moist air in micro-tube reactors with different numbers and shapes of inner wall protuberances are investigated in this paper. The micro-reactor with one rectangular protuberance (six different sizes) was studied firstly, and it is shown that reactions near the protuberance are mainly controlled by diffusion, which has little effect on the outlet temper...