Thermal Plume Turbulent Enhancement, Reverse Transition, and Relaminarization in Stably Stratified Enclosure

Noto, Katsuhisa; Meguro, Yoshiharu; Nakajima, Tatsuo

doi:10.2514/2.6579

Cited by 11 publications

(19 citation statements)

References 16 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The aspect ratio of the enclosure, the wire position, and the kind of fluid are the same as those in the previous experiments [5][6][7][8][9], that is, A = 1. When the Ra number is larger than the value [5][6][7][8][9] at the unstratified condition, the plume sways [18,19] naturally from right to left.…”

Section: Physical Conditions For Computationmentioning

confidence: 96%

“…That is, the flow visualization, measurement, and spectrum analysis in the experimental results [5][6][7][8][9] show that the thermal fiow is two-dimensional and laminar at the minimum heat flux used in the experiments [5][6][7][8][9]. Accordingly, the wire heat fiux in the present computation is made smaller than the minimum heat fiux in the experiment [5 9].…”

Section: Physical Modelmentioning

confidence: 97%

“…When the Ra number is larger than the value [5][6][7][8][9] at the unstratified condition, the plume sways [18,19] naturally from right to left. For this swaying motion, the amplitude and frequency are increased by stable stratification [5,[7][8][9]. Here, a plume is defined as a thermal flow rising continuously.…”

Section: Physical Conditions For Computationmentioning

confidence: 99%

“…Experiments [5][6][7][8][9] with the present model have been carried out previously. That is, the flow visualization, measurement, and spectrum analysis in the experimental results [5][6][7][8][9] show that the thermal fiow is two-dimensional and laminar at the minimum heat flux used in the experiments [5][6][7][8][9].…”

Section: Physical Modelmentioning

confidence: 99%

“…The previous studies [2][3][4][5][6][7][8][9] suggest that the thermal flow in stably stratified fluid is time-dependent. However, this time dependence has not been elucidated entirely in previous studies.…”

Section: Introductionmentioning

confidence: 98%

See 4 more Smart Citations

Temperature Field With Thermal Cylinders in Buoyant Flow in Stably Stratified Air

Noto

Mitsuhashi

2005

Numerical Heat Transfer, Part A: Applications

Self Cite

View full text Add to dashboard Cite

The aim of this work is to clarify characteristics of time-dependent temperaltire behavior in a buoyant flow in stahly stratified air in an enclosure. For this aim, the two-dimensional, laminar, time-dependent continuity equation, Navier-Stokes equations with the buoyancy term, and energy equation are solved numerically by finite-difference methods. The computed results at unstratified condition agree well with the previous results, and validate the numerical accuracy. The present computational methods and procedures are therefore valid, and have sufficient grid resolution. As a result, at an odiahatic ceiling of the enclosure or in stably stratified air in the enclosure, a thermal cylinder with high temperature is discovered to occur intermittently near the plume front, and moves upward. However, a thermal cylinder never occurs at unstratified condition. Furthermore, a thermal cylinder exists in both the instantaneous cros.sover (COl) region at adiahatic condition and the timeaveraged crossover (COM) region at stratified condition. In other words, when a thermal cylinder exists, the region with a thermal cylinder is certainly either COM or COI.

show abstract