Natural Convection Heat Transfer Characteristics of the Annular Fins on the Measuring and Monitoring Devices

Abstract

The paper is based on the observations made in computational fluid dynamics (CFD) modelling of the natural convection phenomena in the annular fins on measuring or monitoring device along with its validation through the experimentation. Navier Stokes equations (N-S) and energy equations (in 3-D) have been fully numerically simulated for full scale monitoring device using multi grid solver of FLUENT 16.0. The experimentation was done to test the numerical simulations and correctness of the flow model. The CFD results were found to be matching with experimental results with some tolerance. Increasing the fin diameter and or thickness results in increasing surface area and volume of the fins which is equivalent to addition of thermal mass. The thermal mass is chunk of a material where some thermal energy gets accumulated. The variation of temperature and physics of the whole phenomenon is discussed using the variation of Nusselt number (Nu) and heat transfer coefficient (h) with respect to non-dimensional diameter(d*) and non-dimensional thickness(t*) along with role of thermal mass. Non-dimensional diameters in the range of 1.5–3.0 and non-dimensional thickness in the range of 0.06–0.16 were tested. Finally, it is concluded that the effect of addition of thermal mass is beneficial in case of increasing the fin diameter but the same is not beneficial in case of increasing fin thickness.