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The impingement and evaporation processes of droplet widely exist in many industrial fields such as fuel injection in combustion engines, spray drying and turbines. When a single droplet falls and impacts on an inclined hot surface under the effect of gravity, it evaporates after contacting with the surface due to the heated transfer. The inclined angle of surfaces has great effects on droplet dynamics and heat transfer. In this work, the pseudo-potential model and a thermal lattice Boltzmann model are combined to simulate the impact process and the heat transfer. Moreover, the Peng-Robinson equation of state is incorporated in the effective density function to consider the large liquid/gas density ratio. The influences of inclined angle on droplet shape and evaporation rate are obtained and analyzed. The results show that for a fixed initial velocity, when the inclined angel increases, droplet deformation is significant as the motion between droplet and the surface is strengthened and the droplet evaporation rate gets faster since the heat transfer is enhanced.
droplet evaporation, impingement, inclined surface, non-ideal equation of state, pseudo- potential model
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