Calculating of the bubble mechanisms heat transfer rate in nucleat boiling

Since the mean characteristic of nucleate boiling is bubble formation and collapse near to heating surface, in this study the attempts have been made to investigate heat transfer effects duet to bubbles ebullition and collapse cycle. All of possible heat transfer mechanisms are studies qualitatively and quantitatively. For quantitative calculation of partial heat transfer by each of introduced mechanisms a series bubble parameters was selected from experimental data which was provided by high-speed photography of a heated rode with nucleat boiling regime on it. The results show that the mechanisms of quenching and turbulent induced by bubble formation and collapse, have the main performance in heat transfer from the heating surface to bulk floe (between 20.5∼40% and 23∼5805% respectively). According to the present results, the share of other mechanisms such as latent heat transfer, super heated layer mixing and single-phase heat transfer are between 6∼15%, 12∼17%, and 3∼5% respectively