A physical model for predicting the minimum stable slug length

A physical model for the prediction of the minimum stable slug length in vertical and horizontal slug flows is presented. The model is based on a new concept of recurrent relaxation of the wall boundary-layer at the slug front and its redevelopment at the slug back. Due to the overlapping process in the developing region the probable average stable slug lengths should range between the predicted minimum stable slug length and twice this value. Comparisons with experimental data is satisfactory. The prediction of the slug length provides an improved method to effect closure for previously existing models for this flow pattern.