A two-dimensional, unsteady, isothermal and two-phase flow of reactant-product mixture in the air-side electrode of proton exchange membrane fuel cells (PEMFC) is studied numerically in the present study. The mixture is composed of oxygen, nitrogen, liquid water and water vapor. The governing equations are two species conservation, a single momentum equation for mobile mixture, liquid mass cons...

Abstract 30MnB5 boron alloyed steel surface is coated using different coating techniques, namely 60(Ni-15Cr-4.4Si-3.5Fe-3.2B 0.7C)-40(WC 12Co) metallic powder plasma spray, Fe-28Cr-5C-1Mn alloy wire arc WC-10Co-4Cr (thick) high velocity oxy-fuel (HVOF), and (fine) diamond jet HVOF. The microstructure of the crude sample consists ferrite pearlite matrices iron carbide structures. intermediate bi...

Experiments have been conducted to study the upward smolder characteristics and the phenomenon of transition to flaming of a porous combustible material in the presence of an air/porous-solid interface. External air flow velocities ranging from 0 m/s to 2.5 m/s are forced upward and forward across the exposed, flat, vertical surface of a high void fraction, flexible, polyurethane foam to examin...

Fuel after inflaming burns at high (till 15-20 МПа and more) pressure, thus is formed gaseous combustion products with temperature 3000-4500 K, which effuse to the ambient space through the nozzle. On length of the nozzle the temperature and pressure of them decrease, and the velocity increases, passing through a sound velocity in minimum (critical) cross-section of the nozzle and reaching 2700...