Due to the complex interaction of the influential parameters, the boiling process is still poorly understood mechanism of heat transfer. For this reason, researchers are trying to gain a clearer insight into the nature of the process on the basis of experimental observations. The characteristics of boiling process arising from the population of the measured temperature fields of the heater surface give us a more detailed insight into the boiling process both at the integral and the local level. Shapes of the heater wall-temperature distributions and their values of the population parameters give us an important level of information on the efficiency of the boiling process at the integral level. At the local level, by analyzing active nucleation sites, the contribution to the temperatures and heat fluxes both during the waiting time and during the growth and bubble detachment time was evaluated. Characteristics of boiling process enable us to analyze the boiling process both on homogeneous as well as on biphilic or selective laser-textured heater surfaces. Laser textured areas are superhydrophilic and have cavities with diameters on a micrometric level. These micro-cavities, in accordance with the nucleation criterion, serve as active nucleation sites. We have shown that the optimum period between the laser-textured parts of the heater surface during boiling of water is equal to its capillary length. The biphilic heater surfaces enhance the boiling heat transfer compared to the untreated heater surfaces.
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