power systems Samira Sayad Saravi, Savvas Tassou Brunel University - - PowerPoint PPT Presentation

2nd International Conference on Sustainable Energy and Resource Use in Food Chains

RCUK Centre for Sustainable Energy Use in Food Chains

Diffuser performance of centrifugal compressor in supercritical CO2 power systems

Samira Sayad Saravi, Savvas Tassou

Brunel University London, Institute of Energy Futures, Centre for Sustainable Energy Use in Food Chains

Uxbridge, Middlesex UB8 3PH, UK

RCUK Centre for Sustainable Energy Use in Food Chains

2nd International Conference on Sustainable Energy and Resource Use in Food Chains

Layout

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RCUK Centre for Sustainable Energy Use in Food Chains (CSEF) Brunel University

• Background
• Literature review
• Real gas effect
• Modelling setup
• Results
• Conclusions

RCUK Centre for Sustainable Energy Use in Food Chains

2nd International Conference on Sustainable Energy and Resource Use in Food Chains

Background

• energy and industry-related

emissions are predicted to be more than double by 2050 compared to 1990 levels [1],

• CO2

is a high density working fluid and is CO2 is a low-cost, non-flammable and non-toxic [2],

• sCO2

systems were

• riginally

conceived for nuclear and concentrated solar power generation applications [3, 4]

3

RCUK Centre for Sustainable Energy Use in Food Chains (CSEF) Brunel University

RCUK Centre for Sustainable Energy Use in Food Chains

2nd International Conference on Sustainable Energy and Resource Use in Food Chains

Review (experiment)

4

RCUK Centre for Sustainable Energy Use in Food Chains (CSEF) Brunel University

Tokyo Institute of Technology, 2012 [5] Sandia National Laboratories, 2010 [6]

RCUK Centre for Sustainable Energy Use in Food Chains

2nd International Conference on Sustainable Energy and Resource Use in Food Chains

Review (modelling)

5

RCUK Centre for Sustainable Energy Use in Food Chains (CSEF) Brunel University

Baltadjiev, Lettieri and Spakovszky, 2015 [7] Behafarid, Podowski, 2016 [8] Pecnik, Rinaldi and Colonna, 2012 [9]

RCUK Centre for Sustainable Energy Use in Food Chains

2nd International Conference on Sustainable Energy and Resource Use in Food Chains

Real gas effect on one-dimensional flow

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RCUK Centre for Sustainable Energy Use in Food Chains (CSEF) Brunel University 𝑒 𝑒𝑦 𝜍𝑣𝐵 = 0 𝑣𝑒𝑣 + 1 𝜍 𝑒𝑞 = −𝑒𝑥𝑡ℎ𝑏𝑔𝑢 𝑒𝑁2 𝑁2 = −2 1 + Γ − 1 𝑁2 1 − 𝑁2 𝑒𝐵 𝐵 + 1 1 − 𝑁2 1 𝜑 𝜖𝜑 𝜖𝑈

𝑞

Γ Γ − 1 𝑒𝑥𝑡ℎ𝑏𝑔𝑢 𝐷𝑞 1 𝐵 𝑒𝐵 𝑒𝑦 → 1 ሻ 2(Γ − 1 1 𝜑 𝑒𝜑 𝑒𝑈 𝑒𝑥𝑡ℎ𝑏𝑔𝑢 𝐷𝑞𝑒𝑦 , 𝑁 → 1

and

Γ = 1 + 𝜍 𝐷 𝜖𝐷 𝜖𝜍 = 1 2 𝜍3𝐷4 ൗ 𝜖2𝜑 𝜖𝑄2 = 𝜑 2𝐷2 ൗ 𝜖2𝑄 𝜖𝜑2 𝐷2 = 𝜖𝑄 𝜖𝜍

𝑡

= −𝜑2 𝜖𝑄 𝜖𝜑

𝑡

> 0

RCUK Centre for Sustainable Energy Use in Food Chains

2nd International Conference on Sustainable Energy and Resource Use in Food Chains

Modelling setup

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RCUK Centre for Sustainable Energy Use in Food Chains (CSEF) Brunel University

Γ Behaviour (Thompson, 1971 [10]) Γ > 1 Sound speed increases with P; behaviour of usual substances Γ = 1 Constant sound speed ; P a linear function of ρ 0 < Γ <1 Sound speed deceases with P Γ = 0 P a linear function of V Γ < 0 Negative curvature of isoentrope; behaviour of unusual substances

RCUK Centre for Sustainable Energy Use in Food Chains

2nd International Conference on Sustainable Energy and Resource Use in Food Chains

Results

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RCUK Centre for Sustainable Energy Use in Food Chains (CSEF) Brunel University

RCUK Centre for Sustainable Energy Use in Food Chains

2nd International Conference on Sustainable Energy and Resource Use in Food Chains

Results (density and sound speed)

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RCUK Centre for Sustainable Energy Use in Food Chains (CSEF) Brunel University

(VN13:- - - , VN17: ̶ ̶ ̶ )

RCUK Centre for Sustainable Energy Use in Food Chains

2nd International Conference on Sustainable Energy and Resource Use in Food Chains

Conclusions

• explicit representation and characterisation of the real gas effects of the fluid
• n the one-dimensional internal flow behaviour and related mechanisms
• The changes in the flow properties have been examined by changing the

cross-sectional area in a selected vaned diffuser

• modelling is performed with ANSYS CFX 17.1, including a generated lookup

table from REFPROP for CO2 real gas properties

• the results show that the model with 17 vanes has higher pressure drop in

throat and can lead to flow instability

• it confirms the fact that the higher number of vanes leads to smaller operation

range for this specific diffuser design

• further investigation is needed to confirm this outcome for higher and lower

incidence angle in leading edge

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RCUK Centre for Sustainable Energy Use in Food Chains (CSEF) Brunel University

2nd International Conference on Sustainable Energy and Resource Use in Food Chains

RCUK Centre for Sustainable Energy Use in Food Chains

Thank you

Samira Sayad Saravi Savvas Tassou

Brunel University London, Institute of Energy Futures, Centre for Sustainable Energy Use in Food Chains

Uxbridge, Middlesex UB8 3PH, UK

RCUK Centre for Sustainable Energy Use in Food Chains

2nd International Conference on Sustainable Energy and Resource Use in Food Chains

References

[1] Marchal, V., Dellink, R., Vuuren, D. V., Clapp, C., Château, J., Lanzi, E., Magné, B., and Vliet, J. V., 2011, “OECD Environmental Outlook to 2050,” Accessed January 3, 2018, <https://www.oecd.org/env/cc/49082173.pdf>. [2] Kulhanek, M., and Dostal, V., 2011, “Supercritical carbon dioxide cycles thermodynamic analysis and comparison,” Supercritical CO2 Power Cycle Symposium, Boulder, Colorado, May 24–25. [3] Ahn, Y., Bae, S. J., Kim, M., Cho, S. K., Baik, S., Lee, J. I., and Cha, J. E., 2015, “Review of supercritical CO2 power cycle technology and current status of research and development,” Nuclear Engineering and Technology, 47(6), pp. 647– 661. [4] Li, M., Wang, J., Li, S., Wang, X., He, W., and Dai, Y., 2014, “Thermo-economic analysis and comparison of a CO2 transcritical power cycle and an organic Rankine cycle,” Geothermics, 50, pp. 101–111. [5] Utamura, M., Fukuda, T. and Aritomi, M. 2012, “Aerodynamic Characteristics of a Centrifugal Compressor Working in Supercritical Carbon Dioxide,” 2nd International Conference on Advances in Energy Engineering (ICAEE 2011), Energy Procedia, pp. 1149–1155. [6] Wright, S., Radel, R., Vernon, M., Rochau, G., and Pickard, P., 2010, “Operation and Analysis of a Supercritical CO2 Brayton Cycle,” Sandia National Laboratories, Albuquerque, NM, Technical Report No. SAND2010-0171. [7] Baltadjiev, N. D., Lettieri, C., and Spakovszky, Z. S., 2015, “An Investigation of Real Gas Effects in Supercritical CO2 Centrifugal Compressors,” J. Turbomach., 137, pp. 091003(1–13). [8] Behafarid, F., Podowski, M. Z., 2016, “Modelling and Computer Simulation of Centrifugal CO2 Compressors at Supercritical Pressures,” J Fluids Eng, 138, pp. 061106 (1–9). [9] Pecnik, R., Rinaldi, E., and Colonna, P., 2012, “Computational Fluid Dynamics of a Radial Compressor Operating With Supercritical CO2,” J Eng Gas Turb Power, 134, pp. 122301(1–8). [10] Thompson, P.A., 1971, “A Fundamental Derivative in Gas Dynamics,” Physics of Fluids, 14 (1971): 1843–1849. 12

RCUK Centre for Sustainable Energy Use in Food Chains (CSEF) Brunel University