1. 1 Estimation of Dynamic Force Coefficients from a Wet (Foamy) Annular Seal Progress Year 1 May 2013 33 rd Turbomachinery Research Consortium Meeting Gary Bradley M.S. Student TRC Project 32513/1519NS Luis San Andrés Mast-Childs Professor $ 44,984

2. Bubbly mixture annular seals As oil fields deplete compressors work off-design with liquid in gas mixtures, mostly inhomogeneous. Similarly, oil compression station pumps operate with gas in liquid mixtures. The flow condition affects compressor or pump overall efficiency and reliability. Little is known about seals operating under 2-phase conditions, except that the mixture affects seal leakage and system reliability. Justification Seals operate with either liquids or gases, but not both….. San Andrés, L., 2012, “Rotordynamic Force Coefficients of Bubbly Mixture Annular Pressure Seals, ”ASME J. Eng. Gas Turbines Power, vol. 134 (Feb), 022503

3. 3 Proposed Work (Year 1) Prepare test rig for measurements (50%) Seal test rig (100%) Center journal/bearing, calibrate instrumentation, install shakers (100%) Prepare motor to run up to 6000 rpm (50%) Prepare oil supply/return system (50%) Make air/oil mixing fixture that will produce consistent wet (foamy) mixtures (50%) Fabricate mixing device Prepare mixing device for supply pressure up to 100 psig Construct de-aeration device Perform initial dynamic load measurements and devise a procedure to extract the characteristic force coefficients (0%) $ 44,984

4. 4 Revamped vertical SFD rig Air Inlet Oil Inlet (ISO VG 10) Test seal section Valves Sparger (mixing) element

5. 5 Test Rig Preparation Seal section is currently assembled and air tight with no leaks Oil supply/return pumps all currently in working order Air supply in working order (awaiting air flow meter calibration) Mixing (sparger) element currently producing mixtures (homogeneity of mixture to be checked)

6. 6 Test Seal Section Top Plate 1 Top Plate 2 Plexiglas bearing Journal (inside) Bottom Plate Gasket O-ring Seal dimensions Clearance, c=5 mil Length, L=1.0 inch Diameter, D=5.0 inch Difficulties Too many sealing surfaces Sensor placement not ideal Plexiglas threads easily stripped and cracked

7. 7 New Design Test Seal Cartridge Top Plate Bearing (steel) Journal Rotor O-ring Seal dimensions Clearance, c=5-15 mil Length, L=0.5-1.75 inch Diameter, D=5.0 inch Advantages Fewer sealing surfaces Sensor placement as needed Made of steel (no cracking/stripping of material)

8. 8 Progress through Year 1 August 2012 – January 2013 Ph.D. student funded Worked to seal test rig – Did not finish Quit in January of 2013 January 2013 – April 2013 Project went without progress (no student) April 2013 – Present Undergraduate student worker w/ supervision of grad student Sealed test rig (air tight, no leaks) Centered test rig Designed simpler test seal section (for future manufacture) Working to separate air from foamy mixture

9. 9 Outlook for Year 2 June 2013 – August 2013 Finish preparing test rig Estimation of mixture properties (air/oil %, density, viscosity, etc.) Find new graduate student to take over project August 2013 – December 2013 Prepare data acquisition system Make initial measurements January 2014 – May 2014 Identification of seal force coefficients for a number of operating conditions Write comprehensive TRC report and proposal for future work No more funding is sought for 2013-14.