Prediction of the pressure drop during forced circulation of the helical flow
The purpose of this investigation was to perform an experimental evaluation of the pressure drop characteristics for helical flows and compare the results to correlations available in the literature. The results for single-phase turbulent flow yielded a correlation of the form fc/fs = [Re (d/D)^2] which was found to be a good correlation formula in the superheated steam region for a ratio of the coil diameter to the tube diameter of 9.48. The author also proposed several correlation formulas for the pressure drop of a two-phase flow in a helical tube. Although these correlations lack experimental verification, they are shown to be reasonably located between the lower limit data for compressed liquid and upper limit data for superheated steam.