A SEMI-EMPIRICAL CORRELATION FOR ADIABATIC INTERFACIAL FRICTION FACTOR IN HORIZONTAL, AIR-WATER COUNTERCURRENT STRATIFIED FLOW

摘要

A semi-empirical correlation for an adiabatic interfacial friction factor(f(ia)) in a stratified wavy flow, based on the simultaneous measurements of the main flow parameters in air-water countercurrent stratified flows and the concept of surface roughness in a wavy flow, has been developed. The functional form for f(ia), in particular, has been obtained by making an analogy between the effect of surface roughness on the gas-to-wall friction factor(f(g)) in a pipe flow and the effect of gas-water interface roughness on the air-water interface friction factor (f(ia)) in a wavy flow. A total of 186 data points from the present countercurrent flow test and 15 from the concurrent pipe flow reported by others have been used in the present analysis. Comparisons between the data and the predictions of the present correlation shows that the agreement is within +/- 30%. [References: 9]