Ohio University

Transparent Multiphase Corrosion Flow Loops

Multiphase Flow in Hilly Terrain

A unique, 10 cm-diameter, 18 m-long pipeline has been constructed to simulate localized multiphase oil/water/gas flow and corrosion in the vicinity of road and river crossings and in hilly terrain topography with short, abrupt inclination changes. The multiphase flow line involves flow over a horizontal distance of 6 m before reaching the crossing section. Four 9D (nine-diameter radius) bends with 2-m pipelines for the riser, crossing, and downcomer sections make up the crossing section. The multiphase mixture then flows through a 4-m horizontal discharge section into a separation tank. This highly complex system exhibits flow regimes from horizontal, inclined, and vertical flows. At any given gas and liquid flow rate, this system can experience 9 different flow regimes in different regions at the same time. The corresponding corrosion mechanisms and corrosion rates will vary dramatically.

Inclined Multiphase Flow

Unlike single-phase flows, multiphase flows are strongly influenced by the geometry of flow. Of the many variations in pipe geometry, the strongest influence is from the pipe inclination. Even an inclination of 0.5 degrees can dramatically alter the flow patterns, the boundary layer structure, and the fundamental transport mechanisms. Two separate pipelines, 30 m in length, are located atop a 16,000 lb structure that is fully inclinable from horizontal to vertical. The transparent pipe sections allow for flow visualization when studying the effect of inclination on flow patterns in multiphase flows containing sand, oil, water, gas, and/or drag reducing agents (DRAs).