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Research Papers

Unsteady Conjugate Heat Transfer Investigation of a Multistage Steam Turbine in Warm-Keeping Operation With Hot Air

[+] Author and Article Information
Piotr Łuczyński

Institute for Power Plant Technology,
Steam and Gas Turbines,
RWTH Aachen University,
Templergraben 55,
Aachen 52062, Germany
e-mail: luczynski@ikdg.rwth-aachen.de

Dennis Toebben

Institute for Power Plant Technology,
Steam and Gas Turbines,
RWTH Aachen University,
Templergraben 55,
Aachen 52062, Germany
e-mail: toebben@ikdg.rwth-aachen.de

Manfred Wirsum

Institute for Power Plant Technology,
Steam and Gas Turbines,
RWTH Aachen University,
Templergraben 55,
Aachen 52062, Germany
e-mail: wirsum@ikdg.rwth-aachen.de

Wolfgang F. D. Mohr

GE Power AG,
Brown Boveri Str. 7,
Baden 5401, Switzerland
e-mail: wolfgang.mohr@ge.com

Klaus Helbig

GE Power AG,
Boveristraße 22,
Mannheim 68309, Germany
e-mail: klaus.helbig@ge.com

1Corresponding author.

Manuscript received June 22, 2018; final manuscript received July 3, 2018; published online September 14, 2018. Editor: Jerzy T. Sawicki.

J. Eng. Gas Turbines Power 141(1), 011005 (Sep 14, 2018) (11 pages) Paper No: GTP-18-1283; doi: 10.1115/1.4040823 History: Received June 22, 2018; Revised July 03, 2018

In pursuit of flexibility improvements, General Electric has developed a product to warm-keep high/intermediate pressure steam turbines using hot air. In order to optimize the warm-keeping operation and to gain knowledge about the dominant heat transfer phenomena and flow structures, detailed numerical investigations are required. For the sake of the investigation of the warm-keeping process as found in the presented research, single and multistage numerical turbine models were developed. Furthermore, an innovative calculation approach called the equalized timescales method (ET) was applied for the modeling of unsteady conjugate heat transfer (CHT). In the course of the research, the setup of the ET approach has been additionally investigated. Using the ET method, the mass flow rate and the rotational speed were varied to generate a database of warm-keeping operating points. The main goal of this work is to provide a comprehensive knowledge of the flow field and heat transfer in a wide range of turbine warm-keeping operations and to characterize the flow patterns observed at these operating points. For varying values of flow coefficient and angle of incidence, the secondary flow phenomena change from well-known vortex systems occurring in design operation to effects typical for windage, like patterns of alternating vortices and strong backflows. Furthermore, the identified flow patterns have been compared to vortex systems described in cited literature and summarized in the so-called blade vortex diagram. The analysis of heat transfer in turbine warm-keeping operation is additionally provided.

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References

Vogt, J. , Schaaf, S. , and Helbig, K. , 2013, “Optimizing Lifetime Consumption and Increasing Flexibility Using Enhanced Lifetime Assessment Methods With Automated Stress Calculation From Long-Term Operation Data,” ASME Paper No. GT2013-95068.
Helbig, K. , Kuehne, C. , and Mohr, W. F. D. , 2014, “A Warming Arrangement for a Steam Turbine in a Power Plant,” European Patent Application No. EP2738360A1. https://patents.google.com/patent/EP2738360A1
Toebben, D. , Łuczyński, P. , Diefenthal, M. , Wirsum, M. , Reitschmidt, S. , Mohr, W. F. D. , and Helbig, K. , 2017, “Numerical Investigation of the Heat Transfer and Flow Phenomena in an IP Steam Turbine in Warm-Keeping Operation Using Hot Air,” ASME Paper No. GT2017-63555.
Evers, H. B. , 1985, “Strömungsformen im Ventilationsbetrieb Einer ein und Mehrstufig Beschaufelten Modellturbine,” Ph.D. thesis, Leibniz Universitaet-Hannover, Hannover, Germany.
Petrovic, M. , and Riess, W. , 1995, “Through-Flow Calculation in Axial Flow Turbines at Part Load and Low Load,” First European Conference on Turbomachinery-Fluid Dynamic and Thermodynamic Aspects, Erlangen, Germany, Mar. 1–3, pp. 309–326.
Petrovic, M. , and Riess, W. , 1997, “Off-Design Flow Analysis of Low-Pressure Steam Turbines,” Proc. Inst. Mech. Eng., Part A, 211(3), pp. 215–224. [CrossRef]
Herzog, N. , 2008, “Untersuchung von Schwachlastströmungen in mehrstufigen Axialturbinen,” Ph.D. thesis, Leibniz Universitaet-Hannover, Hannover, Germany.
Binner, M. , and Seume, J. R. , 2014, “Flow Patterns in High Pressure Steam Turbines During Low-Load Operation,” ASME J. Turbomach., 136(6), p. 061010.
Sigg, R. , Heinz, C. , Casey, M. V. , and Sürken, N. , 2009, “Numerical and Experimental Investigation of a Low-Pressure Steam Turbine During Windage,” Proc. Inst. Mech. Eng., Part A, 223(6), pp. 697–708. [CrossRef]
He, L. , and Oldfield, M. L. G. , 2011, “Unsteady Conjugate Heat Transfer Modeling,” ASME J. Turbomach., 133(3), p. 031022. [CrossRef]
Menter, F. R. , 1993, “Zonal Two Equation k ω Turbulence Models for Aerodynamic Flows,” AIAA Paper No. 93-2906.
Alizadeh, S. , Saunders, K. , Lewis, L. V. , and Provins, J. , 2007, “The Use of CFD to Generate Heat Transfer Boundary Conditions for a Rotor-Stator Cavity in a Compressor Drum Thermal Model,” ASME Paper No. GT2007-28333.
Lewis, L. V. , and Provins, J. , 2004, “A Non-Coupled CFD-FE Procedure to Evaluate Windage and Heat Transfer in Rotor-Stator Cavities,” ASME Paper No. GT2004-53246.
Bohn, D. , Heuer, T. , and Kusterer, K. , 2005, “Conjugate Flow and Heat Transfer Investigation of a Turbo Charger,” ASME J. Eng. Gas Turbines Power, 127(3), pp. 663–669. [CrossRef]
Diefenthal, M. , Łuczyński, P. , Rakut, C. , Wirsum, M. , and Heuer, T. , 2017, “Thermomechanical Analysis of Transient Temperatures in a Radial Turbine Wheel,” ASME J. Turbomach., 139(9), p. 091001.
Baehr, H. D. , and Stephan, K. , 2010, Wärme- und Stoffübertragung, 7th ed., Springer, Berlin, pp. 128–132.
Diefenthal, M. , Łuczyński, P. , and Wirsum, M. , 2017, “Speed-Up Methods for the Modeling of Transient Temperatures With Regard to Thermal and Thermomechanical Fatigue,” 12th European Turbomachinery Conference (ETC), Stockholm, Sweden, Apr. 3–7, Paper No. ETC2017-160. http://www.euroturbo.eu/paper/ETC2017-160.pdf
Łuczyński, P. , Erdmann, D. , Toebben, D. , Wirsum, M. , Helbig, K. , and Mohr, W. , 2018, “Fast Numerical Calculation Approaches for the Modelling of Transient Temperature Fields in a Steam Turbine in Pre-Warming Operation Using Hot Air,” GPPS Forum 2018, Zurich, Switzerland, Jan. 10–12, Paper No. GPPS-2018-0048.
Łuczyński, P. , Toebben, D. , Wirsum, M. , Mohr, W. F. D. , and Helbig, K. , 2017, “Modeling of Warm-Keeping Process Using Hot Air in Steam Turbines,” J. Power Technol., 97(5), pp. 416–428. http://papers.itc.pw.edu.pl/index.php/JPT/article/viewFile/1270/800
Langston, L. S. , 1980, “Crossflows in a Turbine Cascade Passage,” ASME J. Eng. Power, 102(4), pp. 866–874. [CrossRef]
Sharma, O. P. , and Butler, T. L. , 1987, “Predictions of End-Wall Losses and Secondary Flows in Axial Flow Turbine Cascades,” ASME J. Turbomach., 109(2), pp. 229–236. [CrossRef]
Goldstein, R. J. , and Spores, R. A. , 1988, “Turbulent Transport on the End-Wall in the Region Between Adjacent Turbine Blades,” ASME J. Heat Transfer, 110(4a), pp. 862–869. [CrossRef]
Kawai, T. , Shinoki, S. , and Adachi, T. , 1989, “Secondary Flow Control and Loss Reduction in a Turbine Cascade Using End-Wall Fences,” JSME Int. J., 32(3), pp. 375–387.
Wang, H. P. , Olson, S. J. , Goldstein, R. J. , and Eckert, E. R. G. , 1997, “Flow Visualization in a Linear Turbine Cascade of High Performance Turbine Blades,” ASME J. Turbomach., 119(1), pp. 1–8.
Jeong, J. , and Hussain, F. , 1995, “On the Identification of a Vortex,” J. Fluid Mech., 285(1), pp. 69–94. [CrossRef]

Figures

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Fig. 1

Numerical models used for single and multistage CHT investigation

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Fig. 2

Averaged relative deviation of HTCs for selected values of SF and TS (reference calculation SF 104 TS 10−3 s)

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Fig. 3

Vortex structure in end-wall region in conventional operation [23]

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Fig. 4

Vortex system in conventional flow region of warm-keeping operation

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Fig. 5

Velocity triangles with marked incidence values during warm-keeping operation

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Fig. 6

Angle of incidence at S2–S3 Vane

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Fig. 7

Angle of incidence at R1–R3 Blade

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Fig. 8

Summary of defined flow regions—part 1

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Fig. 9

Summary of defined flow regions—part 2

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Fig. 10

Blade vortex diagram for warm-keeping operation

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Fig. 11

Comparison of stream traces in vortex zone 1 [8] (left), flow analysis (right)

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Fig. 12

Heat flux on the blade in specific flow regions

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Fig. 13

Nu-number at S2–S3 vane surfaces in function of angle of incidence

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Fig. 14

Nu-number at R1–R3 blade surfaces in function of angle of incidence

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Fig. 15

Nu-number at S2–S3 vane surfaces in function of flow coefficient

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Fig. 16

Nu-number at R1–R3 vane surfaces in function of flow coefficient

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