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Abstract To address the need for better understanding of multiphase fluid flow behavior through passive inflow control devices (PICDs), two-phase (oil-water) full-scale flow loop testing on helical and a new ICD design, "Hybrid" has been completed. The primary testing objective was to generate a comprehensive two-phase (oil-water) data set of flow performance curves for the helical ICD and the hybrid ICD. The test included a broad range of flow tests with varying viscosities, water cuts and pressures. The results are presented in an innovative manner using isobaric plots (isobars lines with trend lines for each viscosity value) and Reynolds number vs. Flow Coefficient plots, which can be used to easily compare different ICD performances. Test results confirm that for oil-water flow, a viscosity break point for the helical ICD occurs at 2 centipoise (cP) of medium oil. Below this break point the helical ICD does not promote water production in two-phase flow. Above this viscosity break point, the helical ICD exhibits a physical phenomenon where, at water cuts above 30%, the total flow increases at any given pressure drop promoting water flow. With regards to two-phase oil-water fluid flow, the hybrid ICD performs independently of viscosity for the range tested (up to 200 cP - maximum flow viscosity tested at the lab).The hybrid ICD consistently creates more resistance to water flow than to oil flow, causing total flow to gradually decrease at constant pressure as water cut increases. This effect was more apparent at higher pressure regimes. The functional break point of the hybrid ICD is determined to be above 200 cP. Introduction A comprehensive two-phase (oil-water) data set of flow performance curves for the helix inflow control devices (ICDs) and hybrid ICDs was conducted through extensive laboratory testing to identify the threshold viscosity, and to quantify single and multiphase model validity. These test results confirm that the threshold viscosity is 2 centipoise (cP). At viscosities greater than 2 cP, the test results confirm previously published findings that the helix design exhibits preferential production of water for a given pressure drop in a two-phase flow. Additionally, results verify that the helix ICD behavior exhibits correlation to the single phase model but requires a correction due to non-constant flow coefficient, and does not exhibit correlation when the fluids are multiphase, especially at higher viscosities. |
