Facebook Instagram Youtube Twitter

Phase Change Material – PCM

Phase Change Materials (PCM) are latent heat storage materials. It is possible to find materials with a latent heat of fusion and melting temperature inside the desired range. The PCM to be used in the design of thermal storage systems should accomplish desirable thermophysical, kinetics, and chemical properties.

Thermo-physical Properties

  • Suitable phase-transition temperature for the specific application.
  • High latent heat of phase transition to occupy the minimum possible volume.
  • Melting temperature in the desired operating temperature range.
  • High specific heat to provide for additional significant sensible heat storage.
  • High thermal conductivity to minimize temperature gradient and assist the charging and discharging of energy of the storage systems.
  • Small volume changes on phase transformation and small vapor pressure at operating temperatures reduce the containment problem.

Kinetic Properties

  • High nucleation rate to avoid supercooling of the liquid phase.
  • High rate of crystal growth so that the system can meet demands of heat recovery from the storage system.

Chemical Properties

  • Non-toxic, non-flammable, and non-explosive materials for safety reasons.
  • Long-term chemical stability and complete reversible melt/freeze cycle.
  • No degradation after a large number of freeze/melt cycles.
  • Low corrosivity

Finally, the material must be abundant, available, and cheap to help in the feasibility of using the storage system.

There are a large number of PCMs, and they can be divided into three groups:

  • Organic PCMs
  • Inorganic PCMs
  • Eutectic PCMs

As an example, thermal energy storage can concentrate solar power stations (CSP). The principal advantage is the ability to efficiently store energy, allowing the dispatching of electricity over up to a 24-hour period. In a CSP plant that includes storage, the solar energy is first used to heat the molten salt or synthetic oil to store thermal energy at high temperatures in insulated tanks. Later hot molten salt is used for steam production to generate electricity by steam turbo generator as per requirement. Using latent heat and sensible heat in concentrating solar power stations is possible with high-temperature solar thermal input. Various eutectic mixtures of metals, such as Aluminium and Silicon (AlSi12), offer a high melting point (577°C) suited to efficient steam generation. In contrast, high alumina cement-based materials offer good thermal storage capabilities.

 
References:
Heat Transfer:
  1. Fundamentals of Heat and Mass Transfer, 7th Edition. Theodore L. Bergman, Adrienne S. Lavine, Frank P. Incropera. John Wiley & Sons, Incorporated, 2011. ISBN: 9781118137253.
  2. Heat and Mass Transfer. Yunus A. Cengel. McGraw-Hill Education, 2011. ISBN: 9780071077866.
  3. U.S. Department of Energy, Thermodynamics, Heat Transfer and Fluid Flow. DOE Fundamentals Handbook, Volume 2 of 3. May 2016.

Nuclear and Reactor Physics:

  1. J. R. Lamarsh, Introduction to Nuclear Reactor Theory, 2nd ed., Addison-Wesley, Reading, MA (1983).
  2. J. R. Lamarsh, A. J. Baratta, Introduction to Nuclear Engineering, 3d ed., Prentice-Hall, 2001, ISBN: 0-201-82498-1.
  3. W. M. Stacey, Nuclear Reactor Physics, John Wiley & Sons, 2001, ISBN: 0- 471-39127-1.
  4. Glasstone, Sesonske. Nuclear Reactor Engineering: Reactor Systems Engineering, Springer; 4th edition, 1994, ISBN: 978-0412985317
  5. W.S.C. Williams. Nuclear and Particle Physics. Clarendon Press; 1 edition, 1991, ISBN: 978-0198520467
  6. G.R.Keepin. Physics of Nuclear Kinetics. Addison-Wesley Pub. Co; 1st edition, 1965
  7. Robert Reed Burn, Introduction to Nuclear Reactor Operation, 1988.
  8. U.S. Department of Energy, Nuclear Physics and Reactor Theory. DOE Fundamentals Handbook, Volume 1 and 2. January 1993.
  9. Paul Reuss, Neutron Physics. EDP Sciences, 2008. ISBN: 978-2759800414.

Advanced Reactor Physics:

  1. K. O. Ott, W. A. Bezella, Introductory Nuclear Reactor Statics, American Nuclear Society, Revised edition (1989), 1989, ISBN: 0-894-48033-2.
  2. K. O. Ott, R. J. Neuhold, Introductory Nuclear Reactor Dynamics, American Nuclear Society, 1985, ISBN: 0-894-48029-4.
  3. D. L. Hetrick, Dynamics of Nuclear Reactors, American Nuclear Society, 1993, ISBN: 0-894-48453-2.
  4. E. E. Lewis, W. F. Miller, Computational Methods of Neutron Transport, American Nuclear Society, 1993, ISBN: 0-894-48452-4.

See above:

Energy Storage