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INTRODUCTION
PRINCIPLE & WORKING
TYPES OF PCM
PCM INCORPORATION
BUILDING APPLICATION
BIO PCM
GLASS-X
MERITS & DEMERITS
SELECTION CRITERIA
CASE STUDY
CONCLUSION25/08/2014 2DEPT. OF CIVIL ENGINEERING, TKMCE
• Modern architecture is attractive, flexible and light weight
• Phase Changing Materials - Interior finishing alternatives
• Stores much larger amount of thermal energy per unit
mass than conventional building materials
• Requires less amount of energy for production
• It can charge and discharge energy in the form of latent
heat
25/08/2014 3DEPT. OF CIVIL ENGINEERING, TKMCE
25/08/2014 4DEPT. OF CIVIL ENGINEERING, TKMCE
FIG: PHASE CHANGE MATERIALS
• When heat is applied to any substance, it is transferred in
two ways
Sensible heat
Latent heat
• PCMs works on the principle of latent heat
• Latent heat enables PCMs to control room temperature
25/08/2014 5DEPT. OF CIVIL ENGINEERING, TKMCE
• PCMs used in construction change from solid to liquid at
23ºC - 26ºC
• They melt, absorb heat from room and room temperature
is kept constant until the change of state is complete
• PCM then returned to solid state by night time ventilation /
mechanical means
• When returned to solid state it emits the heat
• The phase change cycle repeats
25/08/2014 6DEPT. OF CIVIL ENGINEERING, TKMCE
25/08/2014 7DEPT. OF CIVIL ENGINEERING, TKMCE
FIG: WORKING OF PCM
• There are many types of PCM but not all are suitable for
use in buildings
• The two main types of PCM used in construction are
inorganic salt hydrates and organic paraffin or fatty acids
• Both materials have a set of advantages and disadvantages
that must be taken into consideration
25/08/2014 8DEPT. OF CIVIL ENGINEERING, TKMCE
INORGANIC SALT HYDRATES
• Salt hydrates are a low-cost, readily available PCM
• They have a high latent heat storage capacity and high
thermal conductivity
• They are also non-flammable
25/08/2014 9DEPT. OF CIVIL ENGINEERING, TKMCE
• Paraffin’s and fatty acids do not expand as they melt, and
freeze without much super cooling
• They are chemically stable, compatible with conventional
construction materials and recyclable
• Paraffin’s are hydrophobic, which means they are water-
repellant
• As a result, their phase-change points are reliable
25/08/2014 10DEPT. OF CIVIL ENGINEERING, TKMCE
• Pure paraffin’s are also highly durable, and do not degrade
in contact with oxygen
25/08/2014 11DEPT. OF CIVIL ENGINEERING, TKMCE
FIG: ORGANICS
• Impregnated into building materials in 2 ways :
Either directly or as pellets
Microencapsulation
• Microencapsulation most preferred always.
• Night cooling considered as the main difficulty
25/08/2014 12DEPT. OF CIVIL ENGINEERING, TKMCE
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FIG : DIRECT USAGE
25/08/2014DEPT. OF CIVIL ENGINEERING, TKMCE 14
• Individual particles of solid/ liquid material are coated with a
continuous film of polymeric material
• Produce capsules called microcapsules
•Microcapsules – small sphere with uniform wall round it
•Micrometer to millimeter range
•Appearance of beads, powder
• Polymer sphere shaped
STRUCTURE OF A MICROCAPSULE :
•Material inside is called core
•Wall is called shell or coating
25/08/2014DEPT. OF CIVIL ENGINEERING, TKMCE 15
MORPHOLOGY :
• Depends on core material and the deposition process of
the shell
• Basically 3 types :
Mononuclear
Poly nuclear
Matrix encapsulation
•Also mononuclear with multiple shells, or clusters of
microcapsules
25/08/2014DEPT. OF CIVIL ENGINEERING, TKMCE 16
25/08/2014DEPT. OF CIVIL ENGINEERING, TKMCE 17
FIG: TYPES OF MICROCAPSULES
PCM AS CEILING MATERIAL
• PCM incorporated into ceiling tiles-effective in controlling
temperature, reducing reliance on air conditioning
BUILDING APPLICATIONS:
25/08/2014DEPT. OF CIVIL ENGINEERING, TKMCE 18
FIG: PCM CEILING
25/08/2014DEPT. OF CIVIL ENGINEERING, TKMCE 19
• Microscopic polymer capsules containing a wax storage
medium, embedded in gypsum and then encased in the
metal tile
FIG: FIXING A PCM CEILING
25/08/2014DEPT. OF CIVIL ENGINEERING, TKMCE 20
• Phase change drywall incorporates PCM within its
structure
• Effective, less costly, and less bulky replacement of the
standard thermal mass (masonry or water) used to store
solar heat
BIO PCM:
• A rolled mat that contains PCM
• Integrated into new construction or retrofitted into existing
• Mat is installed between insulation and drywall layers and
located in walls and ceiling
25/08/2014 21DEPT. OF CIVIL ENGINEERING, TKMCE
GLASSX
• An insulated glazing unit that can be used as full glass walls
and windows
• It has an outer pane of glass that reflects high-angle sun and
allows low-angle sunlight to pass
• These PCMs store the heat from the sunlight, release the heat
to the interior of the building as the temperature cools
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25/08/2014DEPT. OF CIVIL ENGINEERING, TKMCE 23
• Sunlight transmitted through this outer pane of glass passes
through inner polycarbonate channels that are embedded
with salt-hydrate PCMs
FIG: WORKING OF GLASS-X
• A melting temperature range in construction is 23°C or
26°C
• A high latent heat of fusion per unit volume minimizes the
area of PCM tiles that are needed
• High thermal conductivity
•Minimal changes in volume
• Congruent melting
25/08/2014 24DEPT. OF CIVIL ENGINEERING, TKMCE
SELECTION CRITERIA ( Contd…)
25/08/2014 25DEPT. OF CIVIL ENGINEERING, TKMCE
• A completely reversible freezing/melting cycle
• Durability over a large number of cycles
• Non-corrosiveness to construction materials
• Non-flammability
MERITS
Freeze without much supercooling
Ability to melt congruently
Self nucleating properties
Compatibility with conventional material of
construction
No segregation
Recyclable
25/08/2014 26DEPT. OF CIVIL ENGINEERING, TKMCE
DEMERITS
- Low thermal conductivity in solid state
- Flammable
- Corrosive
- Volumetric latent heat storage capacity is low
- Phase segregation
25/08/2014 27DEPT. OF CIVIL ENGINEERING, TKMCE
25/08/2014 28DEPT. OF CIVIL ENGINEERING, TKMCE
• Three semi transparent domes of 18.5, 20, 24m
diameter
• Building has been built in one of the city harbor of
Rotterdam
• Climate is managed in different way in different room
• Exhibition hall temperature is kept about 15 ˚C
• Conference hall temp is maintained about 21˚C
• Temperature is varied with the help of PCM
25/08/2014 29DEPT. OF CIVIL ENGINEERING, TKMCE
FIG: FLOATING BALL OF ROTTERDAM, NETHERLAND
CONCLUSION
• Improves thermal comfort levels and obviate or reduce the
need for air-conditioning
• Reduction in peak temperatures is possible
• Used in Residential buildings too
• Significant advantages for both commercial and residential
buildings
• Night ventilation- an integral part
• Likely to become a valuable tool for improving thermal
comfort in domestic buildings
25/08/2014DEPT. OF CIVIL ENGINEERING, TKMCE 30
REFFERENCES
Zubillaga (2007), “Use of microencapsulated PCM in concrete walls for energy
savings. Energy and Buildings”, Vol. 39 pp.113-119.
I.O. Salyer, A.K. Sircar, R.P. Chartoff, D.E. Miller(1995), “Advanced phase-
change materials for passive solar storage applications”, Proceedings of the
20th Intersociety Energy Conversion Engineering Conference, Warren dale,
Pennsylvania, USA: 699-709.
25/08/2014DEPT. OF CIVIL ENGINEERING, TKMCE 31
THANK YOU
25/08/2014DEPT. OF CIVIL ENGINEERING, TKMCE 32
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