When a fluid flow through a curved tube, centrifugal force acting upon the various elements of fluid moving with different velocities causes secondary circulation. Further secondary flow stabilizes the laminar flow leading of a higher critical Reynolds number for transition from laminar to turbulent flow. Secondary flow results in higher heat transfer characteristics. Helical coils are used for heating or cooling in process tanks. 

Utilities Required:-

•  Electricity 500 watts, 220 V, 1 phase.

•  Floor area 1 m x 2 m.

Experiment:-

•  To compare the pressure drop in helical coil with that in a straight pipe of same length, inside diameter and surface roughness.

•  To determine the critical Reynolds number of a fluid flowing through the coil.

•  To determine the friction factor for flow of water through helical coil.