Effects of Chemical Kinetics on the Gas and Particle Phase Temperatures in Dual- Stage HVOF Thermal Spray Technology

The present work takes into account the impact of chemicalkinetics for the combusting, highly turbulent, subsonicsupersonic,and multiphase flow in a hydrogen fueled dualstage High Velocity Oxygen-Fuel (HVOF) thermal spraycoating system. The interaction between chemistry andturbulence is considered by using Eddy Dissipation Concept(EDC) combustion model. It is found that previouslyutilized turbulence limited combustion models, like EddyDissipation Model (EDM), under predict the gas andparticle phase temperatures. It is quite evident that someradical recombination reactions, which are dominated in theconverging–diverging nozzle, have increasing impact on thegas and particle temperatures. Moreover, the validity ofsome skeptical combustion reactions outside of the gunreported through EDM model in rich mixtures is studied.