Two-phase frictional pressure drop of gas–non-Newtonian liquid flow through helical coils in vertical orientation

Investigations have been carried out to evaluate the two-phase frictional pressure drop for gas–non-Newtonian liquid flow through helical coils in vertical orientation. The experiments performed using nine coils and four different non-Newtonian liquids. The effects of gas and liquid flow rate, coil diameter, and liquid properties on two-phase frictional pressure drop have been illustrated. An attempt has been made to fit the experimental two-phase frictional pressure drop data by the Lockhart and Martinelli [R.W. Lockhert, R.C. Martinelli, Proposed correlation of data for isothermal two-phase two components flow in pipes, Chem. Eng. Prog. 45 (1949) 39–48] correlation and the modified Lockhart–Martinelli correlation as presented by different authors. In another approach, friction factor method was adopted to correlate the experimental data by dimensional analysis. The correlation developed predicts the two-phase frictional pressure drop with acceptable statistical accuracy.