ISSN Online: 2377-424X
International Heat Transfer Conference 4
HEAT TRANSFER TO MERCURY FLOWING IN-LINE THROUGH AN UNBAFFLED ROD BUNDLE: EFFECT OF ROD DISPLACEMENT ON LOCAL SURFACE TEMPERATURE AND LOCAL HEAT FLUX
Abstract
The effects of extent and direction of displacement of a rod on its periperally local surface temperature, local heat flux, local heat transfer coefficient, and local surface temperature fluctuations are reported. The rods were electrical-resistance heaters, consisting of a coiled Nichrome resistor surrounded by compacted MgO and encased in a metal cladding. It was found that displacement of a rod can cause large variations in its local heat transfer characteristics. Aside from pitch: diameter ratio, the main independent parameters affecting these characteristics are: circumferential angle (θ), average heat flux (q2), relative cladding thickness [(r2-r1)/r2], relative cladding conductivity (kw/kf), and flow rate (Pe). For a given displacement, the magnitudes of the circumferential variations in local temperature and heat flux are influenced most by extent of relative displacement (σ) and least by changes in (r2-r1)/r2 and kw/kf.