Workshop: Examining the Science & Technology Enterprise in Naval Engineering

Transcription

1 Transportation Research Board - National Academy of Sciences Committee on Naval Engineering in the 21 st Century Workshop: Examining the Science & Technology Enterprise in Naval Engineering January 13-14, 2010 National Academy of Sciences, Washington, DC Panel 1: The Education & Research Community Perspective Presentation by Spyros A. Kinnas (kinnas@mail.utexas.edu) Ocean Engineering Group (OEG) Professor, Dept. of Civil, Arch., & Env. Engineering Associate Director, Offshore Technology Research Center (OTRC) The University of Texas at Austin

2 Ocean Engineering Group (OEG) at UT Austin Graduate studies program - Part of Civil, Architectural, and Environmental Engineering which currently has 724 undergraduate and 416 graduate students Research in the area of computational hydrodynamics with applications on the design of propulsors and offshore structures, performed at the Computational Hydrodynamics Laboratory (CHL)* Graduates are placed in the offshore industry, research companies, and academia Interaction with MIT through consortium on cavitation of high speed propulsors Interaction with Texas A&M University through OTRC (Offshore Technology Research Center) Interaction with Florida Atlantic University and UC Berkeley through ONR s NNR-NE program` *CHL currently has two computer clusters: an older one of 16-node 2-CPU each, and a newer one 16-node 2-Quad-core CPU each Workshop on S&T in Naval Engineering, Jan , 2010, Washington, DC S.A. Kinnas, Ocean Eng. Group, UT Austin 2

3 Educational program (1/2) Introductory Ocean Engineering (CE358) Undergraduate Senior Level Elective. Course includes: theory and applications of inviscid and viscous flows with emphasis on wave mechanics (with design project in which the students make extensive use of CFD) (offered every fall; average attendance: 30 students). Special feature: Electronic Classroom on Ocean Wave Theory: (developed by UT Austin and TAMU with support by NSF) with Text and Educational Interactive Applets (click under Interactive Tools) Examples: Wave kinematics and Wave Forces on Piles Applets The user can change the wave characteristics and receive moving wave profiles and particle trajectories (on the left) and wave forces on the pile (on the right) Workshop on S&T in Naval Engineering, Jan , 2010, Washington, DC S.A. Kinnas, Ocean Eng. Group, UT Austin 3

4 Educational program (2/2) Computational Fluid Dynamics CFD (CE380T) Graduate Level course with emphasis on finite volume methods and incompressible flows (offered every other year; average attendance: 14 students) Boundary Element Methods (BEM or Panel Methods) (CE380P) Graduate level course with fundamentals and applications in fluid mechanics and in structural mechanics (offered every three years; average attendance: 10 students) Hydrodynamics of Propulsors (CE397) Graduate level course. Includes hydrofoil, lifting line, and lifting surface theories with applications to propeller performance prediction and design, and (new material) hydrodynamics of turbines (offered every 4 years; average attendance: 7 students) sheet cavitation Workshop on S&T in Naval Engineering, Jan , 2010, Washington, DC S.A. Kinnas, Ocean Eng. Group, UT Austin 4

5 Continued Education program Fundamentals of Offshore Structures & Design of Fixed Offshore Platforms two-week intensive short course (5.6 CEUs lecturers from academia and industry). It includes hydrostatics, wave mechanics and wave and current forces, structural aspects, dynamics, response to earthquakes, seafloor aspects, design and construction considerations, design parameter specifications, reliability-based design, transportation, installation and certification. (offered every spring; average attendance: 30 participants, most of them are new hires by the offshore industry) Design of Floating Production Systems one-week intensive short course (3.2 CEUs lecturers from academia and industry). It includes stability and response to waves, wind and currents, design and structural aspects of hull and deck, tension legs, risers, mooring and foundation aspects, and reliability aspects, with applications to semi-submersibles, TLPs, and FPSOs (offered every spring; average attendance: 30 participants, most of them are new hires by the offshore industry) Workshop on S&T in Naval Engineering, Jan , 2010, Washington, DC S.A. Kinnas, Ocean Eng. Group, UT Austin 5

6 OTRC (Offshore Technology Research Center) NSF Engineering Research Center (ERC) joint between Texas A&M Univ. and UT Austin; created in 1988, graduated in Since 1999 OTRC has been supported by MMS (Minerals Management Service) and a Consortium of the Offshore Industry. Special feature: Wave Basin at TAMU campus 45.7mx30.5mx5.8m with 3-D wave maker along with wind and current generators, and 9.1mx4.6m pit of adjustable depth (5.8m-16.8m) Workshop on S&T in Naval Engineering, Jan , 2010, Washington, DC S.A. Kinnas, Ocean Eng. Group, UT Austin 6

7 OEG research addresses prediction of performance and design of marine propulsors Contra-rotating Ducted Podded Rim-driven Water-jet Surface-piercing Workshop on S&T in Naval Engineering, Jan , 2010, Washington, DC S.A. Kinnas, Ocean Eng. Group, UT Austin 7

8 OEG s research on marine propulsors includes Development of numerical methods (MPUF-3A vortex lattice method, PROPCAV-panel method) for the prediction of steady, unsteady and cavitating performance of the propulsors (including thrust breakdown due to cavitation) and their effect on the hull (HULLFPP) Coupling of these methods with an Euler solver (GBFLOW) or commercial RANS solvers (Fluent, STAR-CCM+) to predict the interaction with the hull and the effective wake to the blades Devepment of methods for the prediction of rudder cavitation and interaction with propeller Development of optimization methods for propeller blade design, wetted or cavitating, in the actual inflow. These methods are coupled with predictive methods: CAVOPT-3D: uses B-spline representation of propeller blade, CAVOPT-BASE: uses multiplicative factors to adjust given propeller geometry. Workshop on S&T in Naval Engineering, Jan , 2010, Washington, DC S.A. Kinnas, Ocean Eng. Group, UT Austin 8

9 Who supports our research on propulsors? The University/Navy/Industry Consortium on Cavitation of High Speed Propulsors (formed in 1993, now in Phase V) ONR on water-jets ( ) (Monitor: Dr. Ki-Han Kim) ONR /NNR-NE on developing educational tools for propulsor design ( ) (Monitor: Ms. Kelly Cooper) ONR /T-Craft ( ) on improving model for surface piercing props (Monitor: Ms. Kelly Cooper) Workshop on S&T in Naval Engineering, Jan , 2010, Washington, DC S.A. Kinnas, Ocean Eng. Group, UT Austin 9

10 Educational web-based interactive tools developed by OEG with support by ONR s NNR-NE Propeller Geometry Visualization & Design Applet PRELIMINARY version: The users can choose from a list of known propellers geometries (to be enhanced continuously) and then see the perspective view of the propeller using Java-3D (view shown on the left), which allows the users to look at the propeller from any point of view and zoom (view shown in the middle) anywhere they wish. Finally, the users can submit a given thrust coefficient and see the resulting propeller design for best efficiency (view of a designed rim propeller geometry shown on the right). Workshop on S&T in Naval Engineering, Jan , 2010, Washington, DC S.A. Kinnas, Ocean Eng. Group, UT Austin 10

11 What should be addressed next? (in addition to improving/validating current models) Integrate propulsor analysis/design tools with those for hulls (when possible via I/O, so that different tools can be interfaced) Develop predictive tools for propulsor performance in extreme motions due to weather conditions (and couple with those for hulls in extreme motions) Continue with the development of interactive educational tools for the design of propulsors (include several types of propulsors and representative inflow conditions) Workshop on S&T in Naval Engineering, Jan , 2010, Washington, DC S.A. Kinnas, Ocean Eng. Group, UT Austin 11

12 Back-up Slides Workshop on S&T in Naval Engineering, Jan , 2010, Washington, DC S.A. Kinnas, Ocean Eng. Group, UT Austin 12

13 How good are OEG s predictive models? Experiments in non-axisymmetric inflow (at MIT s cavitation tunnel) Computations (PROPCAV/coupled with GBFLOW in the presence of tunnel) θ=-30 o θ=6 o θ=30 o Workshop on S&T in Naval Engineering, Jan , 2010, Washington, DC S.A. Kinnas, Ocean Eng. Group, UT Austin 13

14 Predicted cavity shapes (from PROPCAV, including effects of tunnel) compared with experiment on 4990 Hydrofoil tested at DTMB

15 Validation with experiments on propeller DTMB 4383 K T, 10K Q Propeller 4383, 72 o skew K T 10K Q Z Y X K T, 10K Q σ v =5.0 σ v =5.0 σ v =3.0 σ v =1.0 Propeller 4383, skew=72 o Experiment (wetted) Experiment (cavitating) PROPCAV 10K Q 0.2 Experiment MPUF-3A PROPCAV J A Open (wetted) water performance 0.2 σ v =3.0 σ v = J A K T Comparison of Thrust and Torque With experiments in the case of cavitation induced thrust breakdown Workshop on S&T in Naval Engineering, Jan , 2010, Washington, DC S.A. Kinnas, Ocean Eng. Group, UT Austin 15

16 Validation with experiments on super-cavitating propeller (SRI) Workshop on S&T in Naval Engineering, Jan , 2010, Washington, DC S.A. Kinnas, Ocean Eng. Group, UT Austin 16

17 Validation with experiments on surface-piercing propeller M841-B J A =1.0 J A =1.2 Workshop on S&T in Naval Engineering, Jan , 2010, Washington, DC S.A. Kinnas, Ocean Eng. Group, UT Austin 17

18 Validation with Experiments: Surface-Piercing Propeller M841B θ =0 o,90 o, 180 o θ =30 o, 120 o, 210 o Comparison of ventilation patterns θ =60 o, 150 o, 240 o Workshop on S&T in Naval Engineering, Jan , 2010, Washington, DC S.A. Kinnas, Ocean Eng. Group, UT Austin 18

19 BEM vs. FVM (application to surface-piercing hydrofoil) Vinayan, PhD 09, UT/OEG BEM takes 16 mins on a single processor FVM (Fluent) takes 36 hours running parallel in 6 processors Workshop on S&T in Naval Engineering, Jan , 2010, Washington, DC S.A. Kinnas, Ocean Eng. Group, UT Austin 19

20 What linear theory misses? Workshop on S&T in Naval Engineering, Jan , 2010, Washington, DC S.A. Kinnas, Ocean Eng. Group, UT Austin 20

21 Validation with experiments on ducted propeller (P1452 Propeller + D15 Duct) Workshop on S&T in Naval Engineering, Jan , 2010, Washington, DC S.A. Kinnas, Ocean Eng. Group, UT Austin 21

22 Validation with experiments on ducted propeller (P1452 Propeller + D15 Duct) Note : σ v = σ n J 2 Workshop on S&T in Naval Engineering, Jan , 2010, Washington, DC S.A. Kinnas, Ocean Eng. Group, UT Austin 22

23 Prediction of performance of axial water-jet pump: ONR-AxWJ-1 (1/2) Torque on rotor vs. flow-rate Workshop on S&T in Naval Engineering, Jan , 2010, Washington, DC S.A. Kinnas, Ocean Eng. Group, UT Austin 23

24 Prediction of performance of axial water-jet pump: ONR-AxWJ-1 (2/2) Headrise vs. flow-rate Workshop on S&T in Naval Engineering, Jan , 2010, Washington, DC S.A. Kinnas, Ocean Eng. Group, UT Austin 24

25 OTRC (Offshore Technology Research Center) Research (most recent) in the following areas: Vortex Induced Vibrations Prediction and Mitigation FPSO Roll Prediction and Mitigation Numerical Wave Tank Underwater Mudslides (Stability and Hydroplaning) Suction Caissons (experiments and predictive models) Torpedo Anchors (prediction of entrainment length into the soil) Ice Ridge Gouging (water/soil/pipeline interaction) Risk analysis of offshore platforms For some cases bilge keels might increase roll! Color plot of vorticity (predicted) Workshop on S&T in Naval Engineering, Jan , 2010, Washington, DC S.A. Kinnas, Ocean Eng. Group, UT Austin 25

26 Floating Production systems for Storage and Offloading (FPSO) FPSO Hulls can suffer from excessive Roll Motions (periodic angular motions about the longitudinal axis) Workshop on S&T in Naval Engineering, Jan , 2010, Washington, DC S.A. Kinnas, Ocean Eng. Group, UT Austin 26

27 Other educational web-based interactive tools developed by OEG (used in undergraduate teaching of Fluid Mechanics, CE319F) Fluid Mechanics Applets: Example: Hydrofoil Applet The user can change thickness, camber, and angle of attack and receive the corresponding pressure distribution (shown on the right) which is evaluated by the applet by using a panel method Workshop on S&T in Naval Engineering, Jan , 2010, Washington, DC S.A. Kinnas, Ocean Eng. Group, UT Austin 27

28 Time-Resolved Particle Image Velocimetry System (TR-PIV) (part of lab of undergraduate teaching of Fluid Mechanics, CE319F) Nd:YAG Laser System Components Laser Beam Nano sense Camera Flume Control Unit Timing Hub Traverse System Chiller Flow visualization Lab Visualization & measurement of flow around cylinder Workshop on S&T in Naval Engineering, Jan , 2010, Washington, DC S.A. Kinnas, Ocean Eng. Group, UT Austin 28

29 and some water-turbines (used to generate energy from ocean currents) Workshop on S&T in Naval Engineering, Jan , 2010, Washington, DC S.A. Kinnas, Ocean Eng. Group, UT Austin 29

30 Prediction of performance of tidal turbines Comparisons of the predicted thrust coefficient and power coefficient for varying TSR=ωR/V Cthrust vs. TSR Cpower.vs. TSR Workshop on S&T in Naval Engineering, Jan , 2010, Washington, DC S.A. Kinnas, Ocean Eng. Group, UT Austin 30

31 Prediction of Cavitation Workshop on S&T in Naval Engineering, Jan , 2010, Washington, DC S.A. Kinnas, Ocean Eng. Group, UT Austin 31