DOUBLE DIFFUSIVE CONVECTION IN A SEMICIRCULAR SLICE WITH INTERNAL HEAT GENERATION IN ONE OR BOTH LAYERS

• Published in: Experimental heat transfer 2001-10, Vol.14 (4), p.283-297
• Main Authors: THEERTHAN, S. A, KOLB, G, SEHGAL, B. R
• Format: Article
• Language: English
• Subjects: Applied sciences; Boundary layers; Density measurement (specific gravity); Energy; Energy. Thermal use of fuels; Exact sciences and technology; Fission nuclear power plants; Heat flux; Installations for energy generation and conversion: thermal and electrical energy; Interfaces (materials); Paraffin oils; Saline water; Solubility; Temperature measurement; Thermal conductivity of liquids; Thermal stratification
• ISSN: 0891-6152; 1521-0480
• DOI: 10.1080/089161501317098326

Experiments were performed on convection in a two-layer, stably stratified pool, in the SIMECO experimental facility: a semicircular slice vessel, with internal heat generation in one or both layers. The objective was to study the effect of stratification on the heat transfer to the boundaries of the pool. Effects of miscibility or immiscibilty of the layers and the density difference between the layers were investigated. The stratification with miscible fluids was established using salt water and pure water and that for immiscible fluids was established using pure water and paraffin oil. The concentration of salt in the upper layer was measured using a conductivity probe. The results show that the presence of an interface significantly changes the heat flux distribution along the downward/sideward (semicircular) boundary, decreasing the ratio of up/down heat fluxes by a factor of 4. The mixing of the interface, when both the layers are internally heated, is complete only when Ri h 5. The mixing times for the two layers, when only the lower layer is internally heated are correlated by a simple relation between the fluid parameters and the heat input.