The use of an artificial roughness on a surface is an effective technique to enhance the rate of heat transfer to fluid flow in the duct of a solar air heater. This paper presents a comparison of effective efficiency of solar air heaters having different types of geometry of roughness elements...

The performance characteristics of a solar heater and heat exchangers can be effectively improved by using artificial roughness in different forms, shapes and sizes. Artificial roughness is provided in the form of different geometries such as ribs, dimple shape roughness, wire mesh, baffles,...

The low thermal properties of liquids have led to investigations into additives of small size (less than 100nm solid particles) to enhance their heat transfer properties and hydrodynamic flow. To summarise the experimental and numerical studies, this paper reviews these computational simulations...

Artificial roughness in the form of repeated transverse chamfered rib-groove roughness on one broad wall has been proposed as a convenient method for enhancement of thermal performance of solar air heater. An experimental investigation on heat and fluid flow characteristics of fully developed...

In this investigation, thermo-hydraulic performance of rectangular ducts roughened with a new configuration of ‘V-down rib having gap’ on one wide wall is determined. Small symmetrical gap equal to rib height is created at the centre of both legs of V of continuous V-down rib. The duct has...

This paper presents thermo-hydraulic performance comparison of rib roughness under investigation, ‘V-down ribs with gap’ and similar reported rib roughness geometries used in solar air heater duct. The present rib roughness has flow-attack-angle and relative roughness height of 60° and...