Influences of refrigerant-based nanofluid composition and heating condition on the migration of nanoparticles during pool boiling. Part II: Model development and validation

The objective of this study is to propose a model for predicting the migration characteristics of nanoparticles during the refrigerant-based nanofluid pool boiling. In establishing the present model, the departure and rising processes of bubble, as well as the movement of nanoparticles in the liquid-phase are firstly simulated; then the capture of nanoparticles by bubble and the escape of nanoparticles from the liquid–vapor interface are simulated; finally, the migration ratio of nanoparticles is obtained by flotation theory combining the analysis on the boiling process. The proposed model can predict the influences of nanoparticle type, nanoparticle size, refrigerant type, mass fraction of lubricating oil, heat flux and initial liquid-level height on the migration of nanoparticles. The migration ratio of nanoparticles predicted by the model can agree with 90% of the experimental data of within a deviation of ±20%, and the mean deviation is 12.1%.

► A model was proposed for predicting the migration characteristics of nanoparticles.
► The movements of bubbles and nanoparticles were simulated.
► The interaction between nanoparticles and bubble was considered in the model.
► The flotation theory was introduced into the model.