Relationship between heat flux at minimum evaporation time of droplet and critical heat flux for pool boiling (Extension to Quenching temperature of high temperature surface with droplets)

Abstract

An evaporation of droplet reaches a minimum time at a temperature of hot surface beyond the saturation temperature. Most of researches have mainly focused on the temperature at the minimum time, only. This paper proposed an exact solution to calculate heat flux after a time when the droplet starts contact with the hot surface. The calculated heat flux until a time of about 1 ms when the droplet starts evaporating on the contact surface is found to be very close to the critical heat flux for subcooled pool boiling at the droplet temperature. The average heat flux at the minimum time is firstly determined for the hot surface from which the corresponding initial surface temperature is dependently determined. The quench temperature, furthermore, in a mist cooling for a high temperature material is found to be estimated well by applying the proposed method

Keywords

• droplet evaporation
• boiling
• minimum vapor evaporation time
• critical heat flux
• two-dimensional solution
• quenching temperature