in this paper, a non-isothermal two-phase flow in the cathode gas diffusion layer (gdl) of pem fuel cell is modeled. the governing equations including energy, mass and momentum conservation equations are solved by numerical methods. also, the optimal values of the effective parameters such as the electrodes porosity, gas diffusion layer (gdl) thickness and inlet relative humidity are calculated...

When a heat exchanger in a Fast Breeder Reactor cracks, highly pressurized water or steam escapes into the surrounding liquid sodium. A sodium-water reaction then occurs, forming disodium oxide (and hydrogen gas). It can cause secondary damages to the heat exchangers by the reaction heat and erosion corrosion. The released flow of steam from the cracks of the heat exchanger is an underexpanded ...

4 Phenomenologi al Equation Closure. 7 4 1 Examples 8 Example: River Flow 8 Quasi-equilibrium approximation 8 Example: TraÆ Flow 9 Example: Heat Condu tion 10 Fi k's Law 10 Thermal ondu tivity, difusivity, heat equation 10 Example: Granular Flow 11 Example: Invis id Fluid Flow 12 In ompressible Euler Equations 12 In ompressible Navier-Stokes Equations 12 Gas Dynami s 13 Equation of State 13 Ise...

the growth rate and uniformity of carbon nano tubes (cnts) based on chemical vapor deposition (cvd) technique is investigated by using a numerical model. in this reactor, inlet gas mixture, including xylene as carbon source and mixture of argon and hydrogen as  carrier gas enters into a horizontal cvd reactor at atmospheric pressure. based on the gas phase and surface reactions, released carbon...

in the present work, b-zsm-5 zeolite membranes were synthesized on porous tubular α-alumina supports by several subsequence in situ crystallization hydrothermal treatments. the tio2- bohmite and ɣ- alumina intermediate layers were applied to improve the lattice matching between zeolite layer and the support. the uniform membrane intermediate layers with low permeation resistance were prepared o...

Gas assisted atomization is becoming increasingly important in many industrial applications such as physical, chemical and petroleum processes. In order to achieve proper atomization it is crucial to have proper mixing of gas (air) and liquid (water) in the feeding conduit before it enters into the nozzle. The flow regime, as well as the flow pattern and structure of the flow, are some of the i...

Dusty gas flow through isotropic porous media is considered. The equations governing dusty gas flow through free space are intrinsically averaged in order to derive a comprehensive model that describes flow of a dusty gas through porous media. The developed model is capable of describing flow of mixtures with non-uniform number density through variable porosity media, while taking into account ...

Here we demonstrate a novel concept of liquid-in-gas droplet microfluidics by using gas flow as the continuous phase for the production of liquid droplets. Within a specially configured co-flow microfluidic tubing device, a flow of liquid phase has been continuously dispersed into another outer stream of gas phase, producing discrete and monodisperse microdroplets. This process is robust and we...