The Transient and Stability Behavior of a Natural Convection Loop

Abstract

A study has been made of the transient flow and energy transfer in a natural convection loop. In particular, a toroidal thermosyphon has been considered with orientation in a vertical plane that is heated over the lower half and cooled in the upper half. The basic conservation equations have been solved and the velocity and temperature distributions have been obtained which elucidate the phenomena in natural convection loops. The results include stable, as well as unstable configurations.

Heat Transport in Liquid Filled Tubes

“…One attractive feature of this system is that the dynamics are relatively accessible to analysis (Grief et al 1979). Two-dimensional studies (Mertol et al 1982) have confirmed the essential features of the one-dimensional analysis-which nevertheless does not provide quantitative agreement with experiment.…”

Application of Karhunen-Loève Expansions for the Dynamic Analysis of a Natural Convection Loop for Known Heat Flux

“…In this study, the modeling approach is based on one-dimensional versions of the momentum and energy equations that have been extensively used in the past [6]- [8]. In these, both the fluid velocity u * , and the temperature T * , are averaged over the cross-section, so that u * = u * (t * ) and T * = T * (t * , θ), with t * being time.…”

“…Understanding these systems' time-dependent behavior is important for performance prediction and control. Therefore, toroidal and rectangular loops have been studied both experimentally [3]- [5], and numerically [6]- [8]. From the numerical perspective, both two-and three-dimensional timedependent models have been developed [9,10]; however, one-dimensional versions have been particularly useful to understand the occurrence of chaos in these systems.…”

The effect of an embedded solid block on the onset of convection in a porous cavity

“…Many of these have been concerned with thermo-syphons, and for these the primary topic of interest is heat transfer. Examples are the studies by Greif and colleagues, such as Greif et al (1979), Lavine et al (1986Lavine et al ( , 1987, Mertol et al (1982), Stern and Greif (1987) and Stern et al (1988). The earlier work was reviewed by Mertol and Greif (1985).…”