Flow boiling and flow condensation are often regarded as two opposite or symmetrical phenomena involving the change of phase. There is a temptation to describe both these phenomena with one only correlation, however such method has yet to be suggested. From amongst the structures present in flow boiling and flow condensation at least the annular flow structure seems to be mostly appropriate to the common modeling. However, the shear stress acting between vapour phase and liquid phase is not the same in the respective cases, i.e. flow boiling and flow condensation. Most of modeling of heat transfer in case of condensation inside channels relates the heat transfer coefficient to the friction coefficient. Such approach is rather not commonly used in case of flow boiling. In the latter case, all existing approaches are either the empirical fits to experimental data or form an attempt to combine two major influences to heat transfer, namely the convective flow boiling without bubble generation and nucleate boiling. Generally that is done in a linear or non-linear manner. Alternatively, there is a group of modern approaches based on models which start from modeling a specific flow structure and in such way postulate more accurate flow boiling models, usually pertinent to annular flows.
Authors
Additional information
- Category
- Aktywność konferencyjna
- Type
- publikacja w wydawnictwie zbiorowym recenzowanym (także w materiałach konferencyjnych)
- Language
- angielski
- Publication year
- 2013
