Conjugate Heat Transfer Analysis of a high loaded convection cooled Vane with STAR-CCM+

Transcription

1 STAR Global Conference 2013 March 18-20, Orlando, USA Conjugate Heat Transfer Analysis of a high loaded convection cooled Vane with STAR-CCM+ René Braun, Karsten Kusterer, B&B-AGEMA, Aachen, Germany

2 Content Introduction Upgrade of E-class 160MW gas turbine NASA Vane Mark II test case Geometrical and mesh model Boundary condition for test case calculation Variation of turbulence model and validation with experimental data Calibration of transition model Re-theta Summary STAR Global Conference 2013, Orlando, No. 2

3 Introduction: B&B-AGEMA Founded in 1995, located in Aachen, Germany Independent engineering service company Company Expertise Core Competence in turbomachinery Compressor and turbine design for steam & gas turbines component design & re-design, technology development, reviews, test-rig realization, advisory service research in cooling technologies (e.g. innovative film cooling) Power Plant CFD / CHT Analysis & Flow Optimization of power plant components (cooling tower, valve, condenser, moisture separator, etc.) Thermodynamic Process Calculations & Optimization Contact: Dr.-Ing. Karsten Kusterer B&B-AGEMA GmbH Juelicher Str Aachen Ph.: Fax: info@bub-agema.de STAR Global Conference 2013, Orlando, No. 3

4 New Design of hot gas path of KHI L30A B&B-AGEMA contribution for KHI L30A (30 MWel simple cycle efficiencies >40%) is published and acknowledged by KHI: KHI GT line-up (GT ) Tanaka, R., Koji, T., Ryu, M., Matsuoka, A., Okuto, A.: Development Of High Efficient 30MW Class Gas Turbine - The Kawasaki L30A ASME-paper GT , Copenhagen, Denmark, June Taniguchi, T., Tanaka, R., Shinoda, Y., Ryu, M., Moritz, N., Kusterer, K. : Application of an Optical Pyrometer to Newly Developed Industrial Gas Turbine ASME-paper GT , Copenhagen, Denmark, June 2012 Highest efficient film-cooling is an essential technology to reach high efficiency: STAR Global Conference 2013, Orlando, No. 4

5 Content Introduction Upgrade of E-class 160 MW gas turbine NASA Vane Mark II test case Geometrical and mesh model Boundary condition for test case calculation Variation of turbulence model and validation with experimental data Calibration of transition model Re-theta Summary STAR Global Conference 2013, Orlando, No. 5

6 Upgrade of E-class 160 MW gas turbine with STAR-CCM+ Upgrade designs are performed based on a Delta -analysis: (1) Simplified multi-stage analysis (2) Reference case & conditions (3) Upgrade case & conditions (4) Improved configuration case(s) (5) Similarity operation check (gradients, eigenfrequencies etc.) Example: Upgrade of 1 st Vane increase of turbine inlet temperature CHT calculation of actual design with new condition CHT calculation with TBC application CHT calculation with redesign of inner cooling path configuration and TBC application STAR Global Conference 2013, Orlando, No. 6

7 E-class gas turbine 1st vane CHT calculation cooling air inflow cooling air chamber flow direction main flow path outlet main flow inlet Calculation set up Segregated solver SST-GammaRe-theta Model full conjugate Exhaust gas properties vane mesh specification Fluid: 7.04 million volume cells Solid 1.04 million volume cells Prism layer around outside airfoil: 28 layers, 1.15e-6 m first cell height Prism layer inside flow path: 15 layers, 1.6e-6 m first cell height local refinement area on suction side STAR Global Conference 2013, Orlando, No. 7

8 Upgrade of E-class 160 MW gas turbine with STAR-CCM+ Project Experiences STAR-CCM+ is preferred tool at B&B-AGEMA for full three-dimensional conjugate heat transfer and flow analysis of hot gas path components Results and experiences of many projects have shown excellent agreement of calculated results for STAR-CCM+ and for real behavior STAR-CCM+ is excellent tool for complex and advanced application of real gas turbine configurations of various types and OEM S Theoretical background Understanding and validation of available models and applications within STAR-CCM+ are fundamental and necessary for analyzing of complex three-dimensional components. INFLUENCE OF TURBULENCE MODEL VARIATION STAR Global Conference 2013, Orlando, No. 8

9 Content Introduction Upgrade of E-class 160 MW gas turbine NASA Vane Mark II test case Geometrical and mesh model Boundary condition for test case calculation Variation of turbulence model and validation with experimental data Calibration of transition model Re-theta Summary STAR Global Conference 2013, Orlando, No. 9

10 NASA Turbine Vane Mark II test case: geometrical & mesh model Geometry Overview Midspan Mesh neglect of endwalls (symmetry plane) local refinements cooling air midspan Prism layers => y + < 1 STAR Global Conference 2013, Orlando, No. 10

11 NASA Turbine Vane Mark II test case: boundary condition Inlet Periodicity Outlet Boundary Conditions for vane calculation of Mark II test case: Inlet main flow total pressure: 3.37 bar total temperature: 788 K twist-free inflow Mach number: 0.19 Outlet main flow static pressure: 1.68 bar Boundary conditions cooling holes Inlet Outlet hole heat transfer coefficient temperature W/m²K K W/m²K K W/m²K K W/m²K K W/m²K K W/m²K K W/m²K K W/m²K K W/m²K K W/m²K K STAR Global Conference 2013, Orlando, No. 11

12 Content Introduction Upgrade of E-class 160 MW gas turbine NASA Vane Mark II test case Geometrical and mesh model Boundary condition for test case calculation Variation of turbulence model and validation with experimental data Calibration of transition model Re-theta Summary STAR Global Conference 2013, Orlando, No. 12

13 STAR-CCM+ turbulence models STAR-CCM+ Algebraic models Linear eddy viscosity models one equation models Spalart-Allmaras- Model Reynolds- Averaged Navier- Stokes (RANS) Nonlinear eddy viscosity models Two euqation models k-omega Models SST- GammaReTheta- Model Large Eddy Simulation (LES) Reynolds stress models k-epsilon Models Realizable k- Epsilon Model Detached Eddy Simulation (DES) V2F Model Direct numerical Simulation (DNS) Calculations are done with the coupled solver STAR Global Conference 2013, Orlando, No. 13

14 Variation of turbulence model The predicted pressure distributions of different turbulence models agree all very well with the test results. STAR Global Conference 2013, Orlando, No. 14

15 Variation of turbulence model In laminar region, most turbulence models have large differences from test data. Only SST model agrees well with test data within laminar region. SST model has an over prediction at suction side after first shock. SST model is a little under predicted at pressure side. Pressure side Suction side STAR Global Conference 2013, Orlando, No. 15

16 Content Introduction Upgrade of E-class 160 MW gas turbine NASA Vane Mark II test case Geometrical and mesh model Boundary condition for test case calculation Variation of turbulence model and validation with experimental data Calibration of transition model Re-theta Summary STAR Global Conference 2013, Orlando, No. 16

17 Callibration of transition model Re-theta Pressure side Suction side Re_theta Re_theta: momentum thickness Reynolds number Later onset location of transition Less over prediction after first shock More under prediction at pressure side STAR Global Conference 2013, Orlando, No. 17

18 Content Introduction Upgrade of E-class 160 MW gas turbine NASA Vane Mark II test case Geometrical and mesh model Boundary condition for test case calculation Variation of turbulence model and validation with experimental data Calibration of transition model Re-theta Summary STAR Global Conference 2013, Orlando, No. 18

19 Summary NASA test case The calculated pressure predictions match with test data very well for all turbulence models All turbulence model show quite different surface temperature predictions, especially in laminar region of suction side SST model tends to show the best agreement with test data for temperature prediction among all turbulence models Overall Understanding of implemented models and applications in STAR-CCM+ are necessary to use the right tool within STAR-CCM+ and thus, to maximize the quality of simulations B&B-AGEMA continuously validate new or updated implemented methods within STAR-CCM+ to ensure best quality simulations STAR-CCM+ is preferred tool for CHT and flow calculations STAR Global Conference 2013, Orlando, No. 19