A Predictive Bubble Point Pressure Model for Porous Liquid Acquisition Device Screens

Jason Hartwig; J Adin Mann, Jr

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NASA NTRS · 20190009778

A Predictive Bubble Point Pressure Model for Porous Liquid Acquisition Device Screens

Jason Hartwig·J Adin Mann, Jr

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Abstract

This article presents a simplified model for porous screen channel liquid acquisition devices based on a maximum bubble point pressure method from Adamson and Gast (1997). To validate the model, three 304 stainless steel (325 × 2300, 450 × 2750, and 510 × 3600) mesh samples were tested in methanol, acetone, isopropyl alcohol, and water. Screen pores are estimated based on analysis from scanning electron microscopy, historical data, and current test data. Results show that the bubble point pressure is proportional to the surface tension of the fluid only when accounting for nonzero contact angles. The previous assumption that bubble point pressure scales inversely with effective pore diameter is shown to be invalid, as the second finest 450 × 2750 produced the highest bubble point of the three screens. The simplified bubble point model can be used to make predictions for any pure fluid when pore diameters are based on bubble point tests and not SEM analysis.

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Liquid Acquisition Device Porous Screen Young–LaPlace Surface Tension Contact Angle

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Jason Hartwig, J Adin Mann, Jr. 2014-07-01. A Predictive Bubble Point Pressure Model for Porous Liquid Acquisition Device Screens. https://ntrs.nasa.gov/citations/20190009778

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