A Numerical Analysis of Non-penetrative Convection using a Conditional Average

Abstract

   To investigate turbulent thermal convection which is driven solely by buoyancy, non-penetrative convection without stable stratification is numerically analyzed. In this convection, the heat flux is imposed at the lower wall whereas the upper wall is insulated. In order to examine how much and what kind of flow patterns contribute to some mean values, we obtain conditional averages of vertical-velocity and temperature fluctuations. The probability distribution functions of mean values are also calculated for details. As a result, it is shown that not only coherent structure such as buoyant flow but also its backgrounds have a great influence on statistics in some vertical position. [This abstract is not included in the PDF]