Flow in Concentric Helical Pipe

Concentric helical pipes are used as compact heat exchangers and offer a number of advantages. In this study, the impact of factors such as fluid properties, aspect ratio and coil diameter are studied and its effect on pressure drop and heat transfer. The freeware OpenFoam was used to in order to perform the study. Creo was used to create the geometry and a standard mesher was used to descretize the domain.;The concept of modified friction factor that uses the geometric mean of the coil diameter and tube hydraulic diameter as the relevant scale for friction factor, to concentric helical pipes was examined. Using this scale, the modified friction factor becomes only a function of Dean Number, and the effects of the other two parameters, the coil diameter and the ratio of the inner to outer diameters appear to be wrapped into the new scaling and individually seem to have minimal impact on the modified friction factor. The effect coil geometry on heat transfer was analyzed.