Numerical simulations of nucleate pool boiling are carried out to predict boiling behavior and heat
transfer characteristics. To resolve minute complicated boiling structures in the vicinity of heated wall
at high heat flux a sharp interface model is preferable for the interface capturing. Therefore, a PLICVOF method is employed in this study. A weakly compressible fluid model is employed to avoid
solving Poisson’s equation for pressure [1]. Temperature field is solved with applying its boundary
condition at precise location of liquid-vapor interface in order to evaluate mass flux of evaporation at
the interface exactly. Two kinds of sub-grid scale model for the evaporation near the contact line on the
wall are taken into account: one is microregion model, and the other is microlayer model.
Calculation conditions are shown in table 1. The working fluid is water at atmospheric pressure.
The temperature of heating surface is assumed to be constant. Two kinds of wall superheat, ∆𝑇𝑠𝑎𝑡 =
14℃ and 17℃, are tested. The number of nucleation site is determined based on experimental data [2].
Figure 1 shows examples of boiling behavior predicted by the present simulation, which agrees well
with the experimentally observed boiling mode for the corresponding wall heat flux. It is found that the
predicted wall heat flux using microlayer model is larger than that using microregion model, and the
former agrees well with experimental data [2].
各種検索
サポート
ヘルプ