In the present study, the applicability of widely used evaporation models (Dalton approach-based correlations) is experimentally investigated for natural, forced, and combined convection regimes. A series of experimental measurements are carried out over a wide range of water temperatures and air velocities for 0:01  Gr=Re2  100 in a heated rectangular pool. The investigations show that the evaporation rate strongly depends on the convection regime’s Gr/Re2 value. The results show that the evaporation rate increases with the difference in vapour pressures over both forced convection (0:01  Gr=Re2  0:1) and turbulent mixed convection regimes (0:15  Gr=Re2  25). However, the escalation rate of evaporation decreases with Gr/Re2 in the forced convection regime whereas in the turbulent mixed convection it increases. In addition, over the range of the free convection regime (Gr=Re2  25), the evaporation rate is affected not only by the vapour pressure difference but also by the density variation. A dimensionless correlation using the experimental data of all convection regimes (0:01  Gr=Re2  100) is proposed to cover different water surface geometries and airflow conditions.

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