Southwest Research Institute (SwRI) has upgraded its high-viscosity flow loop (HVFL) to allow multiphase-flow testing.
SwRI initially developed its HVFL in 2015 in response to increasing global production of heavy oil so the industry could better understand flow-equipment performance in extremely viscous conditions.
In a 2 December press release announcing the upgrade, SwRI Senior Research Engineer Josh Neveu said conventional pumping systems struggle to process the volatile mixture of gas and liquid as operators tap into reservoirs with higher gas-volume fractions, so advanced gas separation technologies are necessary.
“This presents an opportunity for more research through evaluating pump performance with highly viscous fluids while also handling gas mixed into the fluid stream, simulating multiphase issues,” he said.
Produced oil is rarely single phase; natural gas is often a component of the production fluid. The introduction of gas into equipment designed for liquid-only operations can affect equipment performance, but multiphase testing for heavy oil can be costly as most facilities are not optimized to handle highly viscous fluids.
“We modified our facility to start mixing air into water to see how pumps designed for single-phase liquid flow will handle multiphase flows. We will transition to heavy oil as well, and test multiphase flows with different viscosities,” Neveu said.
SwRI’s Multiphase Flow Facility already offers multiphase-flow testing at lower viscosities.
In addition to the new multiphase capability, SwRI said it redesigned and optimized the HVFL to create more permanent infrastructure for cost-effective and efficient testing. The upgrade also improved environmental safety by extending the facility’s oil-containment barrier to fully enclose the test setup.
SwRI began the HVFL upgrades in January 2025 and completed them in October. The San Antonio-based organization said it intends other upgrades, including the introduction of heavy-oil multiphase-flow testing, to begin soon.