Cy. Soong et al., Numerical study of bottom-wall temperature modulation effects on thermal instability and oscillatory cellular convection in a rectangular enclosure, INT J HEAT, 44(20), 2001, pp. 3855-3868
In the present study, thermal-fluid behaviors in a rectangular enclosure of
width-to-height aspect ratio 4:1 heated from below with wall-temperature v
aried sinusoidally in ti-me is investigated numerically. The main concerns
are the effects of the wall-heating modulation on the threshold of thermal
instability and the oscillatory cellular convection heat transfer performan
ce at the post-critical conditions. For investigation of heating modulation
effects at various conditions, inclination of the enclosure is also consid
ered. The results demonstrate that a bottom-wall temperature modulation of
larger amplitude and/or lower frequency generates a relatively stabilizing
effect. The trend is the same as those claimed in the previous linear stabi
lity analyses of infinite horizontal fluid layer. However, the present nume
rical solutions further disclosed more detailed information about the flow
structure as well as the local heat transfer performance, which are useful
in understanding of the modulation mechanisms. (C) 2001 Elsevier Science Lt
d. All rights reserved.