Frictional Pressure Drop and Liquid Holdup of Churn Flow in Vertical Pipes with Different Viscosities

Table 4

Pressure drop errors of different models.

Error	Beggs-Brill [24]	Aziz [33]	Hasan [34]	JPI [35]	Present model
AAPE (%)	61.0	46.7	26.8	65.2	9.5
APE (%)	-61.0	2.6	-21.8	-65.2	-1.7