年間 4 号発行
ISSN 印刷: 1065-3090
ISSN オンライン: 1940-4336
Indexed in
DUAL WAVELENGTH INTERFEROMETRY-BASED THREE-DIMENSIONAL SIMULTANEOUS RECONSTRUCTION OF TEMPERATURE AND CONCENTRATION FIELDS IN DOUBLE-DIFFUSIVE SYSTEMS: PART I
要約
The present study is concerned with the development and application of dual wavelength inter-ferometry technique for investigating the transients associated with the three-dimensional temperature and solutal fields in a heat-salt based double-diffusive convection system. The double-diffusive convection phenomenon has been arranged in an octagonal chamber. The dual color interferometer employs two distinct monochromatic lasers, i.e., He-Ne (λ1 = 632.8 nm) and Ar-ion (λ2 = 457.9 nm) as light sources, which individually map the refractive index fields in real time. Experiments have been reported with an initial stability ratio of Rρ ≈ 2.94. The operating experimental conditions constitute an initial concentration step of ΔCi = 0.2 (wt/wt)% and temperature differential of ΔT = 1°C at each horizontal wall. The projection data of the coupled thermal and solutal changes have been recorded in the form of dual-color interferograms from four view angles (0, 45, 90, and 135°). Results have been presented in the form of contour plots of retrieved thermal and solutal fields and reconstructed two-dimensional thermal and solutal fields at select horizontal planes. It has been observed that the diffusive layer convection system undergoes transition from quasi-steady mode convection to other modes of convection, which are functions of both temperature and salinity gradients. With decreasing stability ratio of the system, the thermal transport from the isothermal wall to the fluid layer increases, which leads to development of instabilities in the fluid layer and subsequently at the interface. The development of instabilities in the interface results in enhanced transport of heat and salt between the two layers. Despite the presence of lower levels of thermal gradients, the transition in the flow field and interface is affected by the salinity step at the interface.
-
Choudhury Kaushik, Srivastava Atul, Singh Rajesh Kumar, Kumar Ajai, Laser-produced plasma: Fabrication of size-controlled metallic nanoparticles, in Plasma at the Nanoscale, 2022. Crossref