Natural Convection In Tubes – A Solar Water Heating Application
Free (open access)
V. M. Kriplani & M. P. Nimkar
The present work deals with experimental studies on heat transfer and flow characteristic for buoyancy induced flow through inclined tubes. The parameters that were varied during the experimentation are tube inclination and heat supply. It was found that the mass flow rate and the heat transfer coefficient increase with an increase in heat flux. The flow rate decreases for an increase in the tube inclination. Keywords: thermo siphon, natural convection, buoyancy induced flow, solar water heating system, uniform wall heat flux, renewable energy. 1 Introduction Heat transfer by natural convection inside the tube (circular or square) has a large number of applications in industries. These include solar water heating systems, cooling of gas turbine blades, heat exchangers etc. The heat transfer and flow characteristics with respect to various parameters play a vital role for the design of such systems .The present work is carried out with a specific application in mind, i.e. domestic solar water heating systems. Presently most of the dimensions of solar water heaters are standardized from some other commercial consideration and not necessarily giving the best thermosiphon results. Little information is available in the literature on the heat transfer characteristics for buoyancy-induced flow through inclined tubes [1–4]. The present work aims to study the effect of tube inclination and heat flux on heat transfer and flow characteristics for buoyancy induced flow through inclined tubes, and to develop an experimental model. Hence this work is undertaken.
thermo siphon, natural convection, buoyancy induced flow, solar water heating system, uniform wall heat flux, renewable energy.