Chapter 14
Fabrication and Thermal Performance
Evaluation of Metastable Supercooled
Liquid PCM Based Heat Pack
Rohitash Kumar, Sumita Vyas, Bobin Mondal, Ravindra Kumar
and Ambesh Dixit
Abstract Metastable supercooled liquid phase change material (MSLPCM) is prepared by homogeneous mixing of sodium acetate trihydrate (SAT), water and ethylene glycol (EG) in 92:5:3 weight fractions, respectively. A stainless steel (SS-306)
triggering disk of size 20 mm (L) × 18 mm (W) × 0.2 mm (T) is fabricated by
engraving grooves on SS disk for initiating nucleation in heat pack and release of
heat at the time of requirement. The PCM heat pack containing 300 g PCM and a
triggering disk is fabricated using high frequency PVC sealing machine. Thermal
performance of identical PCM heat pack and water pack (300 g water) is carried
out inside temperature history measuring setup at 0 °C ambient temperature. The
temperature of PCM heat pack and water heat pack reduces from 70 to 30 °C in 210
and 48 min, respectively at 0 °C ambient temperature. The heating time of PCM heat
pack is ~4.4 times more compared to water heat packs.
Keywords Phase change material · Supercooling · T-history · Latent heat · Heat
packs
14.1 Introduction
The prolonged exposure of the human body to very low ambient temperature conditions may cause health problems such as frostbite and hypothermia. It is also very
difficult to go outside for work in such ambient conditions. Therefore, it is desirable
to use insulating clothing for thermal comfort and to reduce heat loss from the body
to the environment, maintaining the safe temperature limits for a human body in an
extreme cold environment. In the case of hypothermia and frostbite conditions, the
external heating source is required to provide heat to the body, maintaining the body
temperature in the safe limit for enhancing blood circulation and to reduce cold socks
R. Kumar · S. Vyas · B. Mondal · R. Kumar
Defence Laboratory, Ratanada, Jodhpur 342011, India
e-mail: dootrohit1976@gmail.com
R. Kumar · A. Dixit (B)
Department of Physics, Indian Institute of Technology Jodhpur, Jodhpur 342037, India
e-mail: ambesh@iitj.ac.in
© Springer Nature Singapore Pte Ltd. 2020
H. Tyagi et al. (eds.), Solar Energy, Energy, Environment,
and Sustainability, https://doi.org/10.1007/978-981-15-0675-8_14
277
Fabrication and Thermal Performance
Evaluation of Metastable Supercooled
Liquid PCM Based Heat Pack
Rohitash Kumar, Sumita Vyas, Bobin Mondal, Ravindra Kumar
and Ambesh Dixit
Abstract Metastable supercooled liquid phase change material (MSLPCM) is prepared by homogeneous mixing of sodium acetate trihydrate (SAT), water and ethylene glycol (EG) in 92:5:3 weight fractions, respectively. A stainless steel (SS-306)
triggering disk of size 20 mm (L) × 18 mm (W) × 0.2 mm (T) is fabricated by
engraving grooves on SS disk for initiating nucleation in heat pack and release of
heat at the time of requirement. The PCM heat pack containing 300 g PCM and a
triggering disk is fabricated using high frequency PVC sealing machine. Thermal
performance of identical PCM heat pack and water pack (300 g water) is carried
out inside temperature history measuring setup at 0 °C ambient temperature. The
temperature of PCM heat pack and water heat pack reduces from 70 to 30 °C in 210
and 48 min, respectively at 0 °C ambient temperature. The heating time of PCM heat
pack is ~4.4 times more compared to water heat packs.
Keywords Phase change material · Supercooling · T-history · Latent heat · Heat
packs
14.1 Introduction
The prolonged exposure of the human body to very low ambient temperature conditions may cause health problems such as frostbite and hypothermia. It is also very
difficult to go outside for work in such ambient conditions. Therefore, it is desirable
to use insulating clothing for thermal comfort and to reduce heat loss from the body
to the environment, maintaining the safe temperature limits for a human body in an
extreme cold environment. In the case of hypothermia and frostbite conditions, the
external heating source is required to provide heat to the body, maintaining the body
temperature in the safe limit for enhancing blood circulation and to reduce cold socks
R. Kumar · S. Vyas · B. Mondal · R. Kumar
Defence Laboratory, Ratanada, Jodhpur 342011, India
e-mail: dootrohit1976@gmail.com
R. Kumar · A. Dixit (B)
Department of Physics, Indian Institute of Technology Jodhpur, Jodhpur 342037, India
e-mail: ambesh@iitj.ac.in
© Springer Nature Singapore Pte Ltd. 2020
H. Tyagi et al. (eds.), Solar Energy, Energy, Environment,
and Sustainability, https://doi.org/10.1007/978-981-15-0675-8_14
277