Project 16FT1: Simulation, Rheology and Efficiency of Polymer Enhanced Solutions

Transcription

1 Marquette University Milwaukee School of Engineering Purdue University University of California, Merced University of Illinois, Urbana-Champaign University of Minnesota Vanderbilt University Project 16FT1: Simulation, Rheology and Efficiency of Polymer Enhanced Solutions Ashlie Martini University of California Merced & Paul Michael Milwaukee School of Engineering CCEFP Webinar October 14, 2016

2 Research Strategy Project Goal: Bridge the gap between fundamental behavior of polymer enhanced fluids and the performance of complex fluid power systems Hydraulic Efficiency Solution Rheology Molecular Structure 2

3 Today s Presentation Next Steps Sept 2016: Complete dynamometer testing of shear stable PMA - MSOE Fall 2016: Perform MD and rheology tests on PIB polymer-containing solutions UC Merced Spring 2017: Test PIB polymercontaining fluids in dyno - MSOE Part I: Characterization of the effect viscosity and shear stability on flow losses for fluids with PMA additives Part II: Development of methods to study the effect of concentration and polymer entanglement on viscosity of fluids with PIB additives 3

4 Part I: Efficiency-Rheology Fluid ID HM46-6 HV46-5 HV46-8 HM46-7 Base Oil Group III Group III Group III Group II 4 cst base oil 54% 54% NA 8 cst base oil 100% 32% 32% NA Polymer nil PMA PMA nil Antiwear additive ZDDP ZDDP ZDDP ZDDP Four ISO viscosity grade 46 antiwear hydraulic fluids Zinc-based antiwear additive Two straight-grade fluids with Newtonian viscosity characteristics HM46-6 and HM46-7 Two multigrade fluids with non-newtonian viscosity characteristics HV46-5 and HV46-8 Same ratio of 4cSt and 8cSt Group III base oils Different polyalkylmethacrylate (PAMA) polymers Low shear stability and high shear stability 4

5 Fluid Viscosity HV46-5 HV46-8 Multi-grade, PMA Additive ASTM D : Standard Test Methods for Rheological Properties of Non-Newtonian Materials by Rotational Viscometer HM46-6 Straight-grade, no PMA 5

6 Shear Stability 100 C ASTM D Standard Test Method for Sonic Shear Stability of Hydraulic Fluids 10.0% 16.2% formulators.dynavis.com Fluid ID Method HM46-6 HV46-5 HV46-8 HM46-7 Kin Vis 40C, cst D445 before shear Kin Vis 40C, cst D5621 after shear Kin Vis 100C, cst D445 before shear Kin Vis 100C, cst D5621 after shear Vis Loss, % Change at 100C UCM Abs Vis 40C, mpa*s rheometer UCM Abs Vis 100C, mpa*s rheometer UCM Kin Vis 40C, cst rheometer UCM Kin Vis 100C, cst rheometer

7 Dynamometer Simulate Polymer solutions under conditions of varying temperature, pressure and shear Formulate Synthetic and conventional hydraulic fluids Evaluate Fluids in the pumps, motors, rheometers and tribometers Model Model pump leakage flow and motor torque losses Motors: Danfoss Series 90 Modified ISO to 4000 psi Pump: Danfoss Series 45 Modified ISO 4409 Axial piston pump Variable displacement 800, 1200, and 1800 rpm 50⁰C and 80⁰C inlet temp 7

8 Circuit Schematic 8

9 Effect of Pressure HM46-6 vs HV46-5 HM46-7 vs HV46-8 9

10 Mean Flow Loss HM46-6 vs HV46-5 HM46-7 vs HV

11 Effect of Shear Stability HM46-6 vs HV46-5 HM46-7 vs HV

12 Relevance of Shear Stability 12

13 Viscosity and Flow Loss HV46-5 Correlation: 0.63 HV46-8 Correlation:

14 Part I Summary The ASTM D5621 sonic shear test provided a good indication of the initial rate of permanent viscosity loss for PAMA containing multigrade oils There appears to be a weak correlation between permanent viscosity loss and system flow losses Hydraulic Efficiency Solution Rheology 14

15 Part II: Rheology-Molecules Goal: Correlate molecular structure of viscosity modifiers to viscous properties of additive-basestock blend Test Fluids: Additive: Polyisobutylene (PIB) Base Oil: PAO 2 Solution Rheology Molecular Structure Initial Objectives: Characterize the effect of molecular weight and partially validate model Explore the effect of entanglement on VM-induced thickening 15

16 Polymers Model of three different molecular weight polymers PIB 1300 PIB1300 PIB2500 PIB4000 # of Repeat Units Molecular Weight (g/mol) PIB 2500 PIB

17 Model Systems All models at 10 wt.% PIB1300 PIB2500 PIB nm 2 nm 2 nm 43 PAO2 2.4 X 2.4 X 4.8 nm 3 80 PAO2 3.0 X 3.0 X 6.0 nm PAO X 3.49 X 6.99 nm 3 17

18 Calculating Viscosity Carreau Equation η 0 η(λ) = η 0 [1 + (λγ) 2 ] p 18

19 Viscosity Results PIB1300 PIB2500 PIB4000 PAO 19

20 Kinematic Viscosity (cst) Partial Validation Measurements for direct comparison coming soon 20

21 Exploring Entanglement Hypothesis: More entanglement = higher viscosity Less viscous? More viscous? Test models: Same concentration and total PIB MW Entanglement possible in one model and on the other Compare viscosity and degree of entanglement 3 x PIB x PIB4000 vs. 21

22 Next Steps Characterize the effect of PIB molecular weight Quantify entanglement of multi-pib models and characterize the effect on viscosity enhancement Create models with different concentrations to explore concentration effect Measure viscosity (rheometer) PIB-PAO2 blends at different concentrations with different PIB molecular weights Test flow loss behavior of PIB containing fluids on dynamometer 22

23 Thank you for your kind attention! Thank you Pascal Society! 23