THERMAL SCIENCE

International Scientific Journal

Umair Munir

,

Murawat Abbas Syed

,

Muhammad Yasar Javaid

,

Muhammad Waqas

,

Hafiz Muhammad Waqas

PHASE ANGLE EFFECT ON HEAT TRANSFER AND INDICATED POWER OF FREE PISTON STIRLING ENGINE

ABSTRACT
In this work, a transient CFD analysis is performed to analyze the effects posed by changing the phase angle between the displacer and power piston in a free piston Stirling engine. The numerical model that is used for analysis is axisymmetric which contains live engine spaces (expansion and compression space) and dead spaces (heater, regenerator, and cooler). The displacer and power piston movements are defined by a user defined function. The results showed that the com¬pression ratio and pressure wave amplitude are strong function of phase angle and peaked at 120° phase angle. The optimum phase angle is also changing with operating frequency. The suitable phase angle at 80 Hz is the range of 60-70°, but at a lower frequency around 50 Hz, its range is 80-100°. The results also showed that the heat transfer rate at the heater and cooler channels are influenced by the change of phase angle. The heat exchange at the heater and cooler is peaked at 90° and 100° phase angle, respectively. The flow losses from the heater, regenerator and cooler showed a rising trend with phase angle increase. The optimum phase angle was obtained by making a balance between phase angle effects and found the optimum range to be between 60°- 80° for peak power and efficiency.
KEYWORDS
Free piston Stirling engine, CFD, Phase angle
PAPER SUBMITTED: 2023-12-12
PAPER REVISED: 2024-03-06
PAPER ACCEPTED: 2024-03-13
PUBLISHED ONLINE: 2024-04-14
DOI REFERENCE: https://doi.org/10.2298/TSCI231212099M
CITATION EXPORT: view in browser or download as text file
THERMAL SCIENCE YEAR 2024, VOLUME 28, ISSUE Issue 6, PAGES [4473 - 4481]
REFERENCES
  1. Ulloa, C., et al., Development of a Transient Model of a Stirling-Based CHP System, Energies, 6 (2013), 7, pp. 3115-3133
  2. Arashnia, I., et al., Development of Micro-scale Biomass-fuelled CHP System Using Stirling Engine, in: Energy Procedia, Elsevier Ltd., Amdterdam, The Netherlands, 2015, pp. 1108-1113
  3. Eames I. W., et al., A Comparative Study of Open and Closed Heat-Engines for Small-Scale CHP Applications, Energies, 9 (2016), 3, 130
  4. Fan, S., et al., Thermodynamic Analysis and Optimization of a Stirling Cycle for Lunar Surface Nuclear Power System, Appl. Therm. Eng., 111 (2017), Jan., pp. 60-67
  5. Garcia, D., et al., Experimental Correlations and CFD Model of a Non-Tubular Heater for a Stirling Solar Engine Micro-Cogeneration Unit, Appl. Therm. Eng., 153 (2019) May, pp. 715-725
  6. Song, Z., et al., Heat Transfer Enhancement in Tubular Heater of Stirling Engine for Waste Heat Recovery From Flue Gas Using Steel Wool, Appl. Therm. Eng., 87 (2015), June, pp. 499-504
  7. Guven, M., et al., Optimization and Application of Stirling Engine for Waste Heat Recovery from a Heavy-Duty Truck Engine, Energy Convers. Manag., 180 (2019), Jan., pp. 411-424
  8. Munir, U., et al., Oscillatory Heat Transfer Correlation for Annular Mini Channel Stirling Heater, Case Studies in Thermal Engineering, 21 (2020), 100664
  9. Salazar, J. L., Chen, W. L., A Computational Fluid Dynamics Study on the Heat Transfer Characteristics of the Working Cycle of a β-Type Stirling Engine, Energy Convers. Manag., 88 (2014) Dec., pp. 177-188
  10. Chen, W. L., et al., A Numerical Study on the Effects of Moving Regenerator to the Performance of a β-Type Stirling Engine, Int. J. Heat Mass. Transf., 83 (2015), Apr., pp. 499-508
  11. Chen, W. L., et al., A CFD Parametric Study on the Performance of a Low-Temperature-Differential γ-Type Stirling Engine, Energy Convers. Manag., 106 (2015), Dec., pp. 635-643
  12. Cheng, C. H., Chen, Y. F., Numerical Simulation of Thermal and Flow Fields Inside a 1 kW Beta-Type Stirling Engine, Appl. Therm. Eng., 121 (2017), July, pp. 554-561
  13. Xiao, G., et al., Design Optimization with Computational Fluid Dynamic Analysis of β-Type Stirling Engine, Appl. Therm. Eng., 113 (2017), Feb., pp. 87-102
  14. Abuelyamen, A., et al., Parametric Study on Beta-Type Stirling Engine, Energy Convers. Manag., 145 (2017), Aug., pp. 53-63
  15. Almajri, A. K., et al., Modelling and Parametric Study of an Efficient Alpha Type Stirling Engine Performance Based on 3-D CFD Analysis, Energy Convers. Manag., 145 (2017), Aug., pp. 93-106
  16. Kuban, L., et al., A 3D-CFD Study of a γ-Type Stirling Engine, Energy, 169 (2019), Feb., pp. 142-159
  17. Caetano, B. C., et al., A Novel Methodology on Beta-Type Stirling Engine Simulation Using CFD, Energy Convers. Manag., 184 (2019), Mar., pp. 510-520
  18. El-Ghafour, S. A., et al., The 3-D Computational Fluid Dynamics Simulation of Stirling Engine, Energy Convers. Manag., 180 (2019), Jan., pp. 533-549
  19. Alfarawi, S., et al., Influence of Phase Angle and Dead Volume on Gamma-Type Stirling Engine Power Using CFD Simulation, Energy Convers. Manag., 124 (2016), Sept., pp. 130 -140
  20. Manmohan, D., Stirling Space Engine Program, Report NASA/CR-1999-209164/VOL2, 1999
  21. Lewandowski, E. J., Johnson, P. K., Stirling System Modelling for Space Nuclear Power Systems, Proceedings, Space Nuclear Conference 2007 (SNC "07), Boston, Mass., USA, 2007
  22. Munir, U., et al., The CFD Methodology for Simulating Pumping Loss from Displacer and Piston Seals of Free Piston Stirling Engine, Thermal Science, 26 (2020), 1A, pp. 13-23
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Phase angle effect on heat transfer and indicated power of free piston Stirling engine

© 2024 Society of Thermal Engineers of Serbia. Published by the Vinča Institute of Nuclear Sciences, National Institute of the Republic of Serbia, Belgrade, Serbia. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution-NonCommercial-NoDerivs 4.0 International licence