Laminar line source starting plumes and their interaction with energy expulsion events
We analyse laminar thermal plumes and their interactions originating from line sources using two-dimensional simulations for a range of Rayleigh numbers ( Ra f , which is based on the constant heat flux supplied at the source), spanning from 10 4 to 10 8 . Initially, a single-plume system is examine...
Gespeichert in:
Veröffentlicht in: | Acta mechanica 2024-05, Vol.235 (5), p.2675-2694 |
---|---|
Hauptverfasser: | , , , , , , |
Format: | Artikel |
Sprache: | eng |
Schlagworte: | |
Online-Zugang: | Volltext |
Tags: |
Tag hinzufügen
Keine Tags, Fügen Sie den ersten Tag hinzu!
|
Zusammenfassung: | We analyse laminar thermal plumes and their interactions originating from line sources using two-dimensional simulations for a range of Rayleigh numbers (
Ra
f
, which is based on the constant heat flux supplied at the source), spanning from
10
4
to
10
8
. Initially, a single-plume system is examined by systematically varying
Ra
f
within the range of
10
4
to
10
8
. Subsequently, we explore a two-plume system, wherein the separation between the sources is within a range of four to twelve times the radius (
R
) of the cylindrical heater. Additionally, we have explored an equivalent single-plume scenario with an effective
Ra
f
of
10
6
. The analysis establishes an empirical correlation for the cap-tip velocity (
v
c
) and the steady-state average temperature of the heater with
Ra
f
. Notably, we observe that the sensitivity of these parameters to variations in
Ra
f
is comparatively lower when compared to that in the case of point source heaters. Furthermore, the merged plume, which manifests in the case of the two-plume system, exhibited heightened stability for larger source separations. This increased stability is due to the diminished generation of vorticity and velocity fluctuations along the plume stem. Interestingly, we observe that the cap-tip velocity of the merged plume remained unaffected by the source separations. Following the merging of plumes, the two-plume system displays lateral mass ejections that increase with the source separations. These lateral mass ejections facilitate augmented heat transfer in the lateral direction, though at the expense of compromised heat transfer in the downstream direction. |
---|---|
ISSN: | 0001-5970 1619-6937 |
DOI: | 10.1007/s00707-024-03854-w |