ABSTRACT
Energy storage materials have the potential to improve the performance of thermal systems due to their excellent thermo-physical properties. Different energy storage materials have been tested for different thermal systems and found adequate to improve their thermal performance. Present work focuses, (i) on the development of two different composite energy storage materials (CESM) by mixing graphite black powder (obtained from lithium batteries cells) in paraffin wax and coconut oil, and (ii) testing of these materials for solar space heating inside the two similar air heating systems namely, Model-2 and Model-3. Air heating trials have been conducted on four different configurations by placing CESM-filled containers on the absorber of the tested heaters. Results of natural and forced convective operations have been compared with a similar conventional air heater (Model-1) and also to some other relevant works on air heating systems. Results revealed that Model-3 is the best model. For this system, improved heat transfer was observed at 356.20 W/m2.K, thermal efficiency was observed at about 78.8%, overall heat loss was computed at 5.91 W/m2.K and maximum exhaust air temperature was observed at about 322.05 K. The cost of Model-3 was about $51.14 (₹ 4110 in Indian currency). Model-3 can be easily developed and used for air heating and drying operations under mild cold climate conditions.
Nomenclature
SAHS | = | Solar air heating system |
SAH | = | Solar air heater |
TES | = | Thermal energy storage |
LHS | = | Latent heat storage |
SHS | = | Sensible heat storage |
CESM | = | Composite energy storage material |
CESM1 | = | CESM prepared by carbon and coconut oil |
CESM2 | = | CESM prepared by carbon and paraffin wax |
TESM | = | Thermal energy storage material |
TPP | = | Thermal performance parameters |
HTC | = | Heat transfer coefficient |
HTF | = | Heat transfer fluid |
HLC | = | Heat loss coefficient |
SWH | = | Solar water heater |
PBP | = | Payback period (years) |
API | = | Average percentage increase |
T | = | Temperature (K) |
η | = | Efficiency (%) |
A | = | Area (m2) |
G | = | Solar radiation (W/m2) |
L | = | Length of the solar collector (m) |
h | = | Heat transfer coefficient (W/m2 K) |
ψ | = | Mass flow rate (kg/s) |
Q | = | heat gain (W) |
Cp | = | Specific heat of the working fluid (J/(kg K)) |
U | = | heat loss coefficient (W/m2 K) |
Subscripts | = | |
amb | = | ambient |
CESM1 | = | CESM1 energy storage material |
CESM2 | = | CESM2 energy storage material |
use | = | useful |
loss | = | overall |
exh | = | exhaust |
p | = | plate of the SAH |
therm | = | thermal |
daily | = | daily (for solar still case) |
elect | = | electrical (for photovoltaic panel case) |
sc | = | solar collector |
cont | = | containers used for CESM filling |
M1 | = | studied Model-1 of SAH (conventional) |
M2 | = | studied Model-2 of SAH (CESM1 operated) |
M3 | = | studied Model-3 of SAH (CESM2 operated) |
Acknowledgements
Authors acknowledge the valuable support of MED, MIT, Moradabad, India.
Disclosure statement
No potential conflict of interest was reported by the author(s).
Correction Statement
This article has been corrected with minor changes. These changes do not impact the academic content of the article.
Additional information
Notes on contributors
Abhishek Saxena
Dr. Abhishek Saxena holds a B.E., M.Tech, and Ph.D in Mechanical Engineering, specializing in Thermal Science. He currently serves as a Professor in Mechanical Engineering (R&D) at the School of Engineering, Dev Bhoomi Uttarakhand University in Dehradun, India. His research focuses on evaluating various designs of solar energy applications (SEA) with and without energy storage materials, including the analysis of household energy consumption and indoor air pollution (IAP). Prof. Saxena is dedicated to achieving sustainability and promoting a clean environment. He also contributes his expertise to leading scientific publishing houses, universities, institutions, labs, and industries. With 22 years of experience in industry, academia, research, and administration, Prof. Saxena has established himself as a versatile and accomplished professional in his field.
Atul A. Sagade
Dr. Atul A. Sagade is working as a professor in the mechanical engineering department of the University of Tarapacá, Chile, and is associated as a visiting professor/scientist with several internationally reputed universities in Europe and South America. Dr. Atul published more than 45 research papers on field experimentation in internationally reputed journals. He is a co-inventor of i) Open Sun Cooling Test for performance evaluation of solar cookers, ii) generalized test methodologies for performance rating and grading of different designs of solar cookers working at intermediate and low temperatures, and iii) thermal methods for determination of effective concentration ratio/factor for solar cookers.
Desh Bandhu Singh
Dr. Desh Bandhu Singh is working as a professor (Mechanical Engineering) at Graphic Era (Deemed to be University), Dehradun, India. During his Ph.D., he received the best research scholar award for 2017 from the Centre for Energy Studies at IIT Delhi. He has published more than 100 research papers in journals of repute on renewable energy applications. He was featured in the list of the top 2% of scientists in the world published by Elsevier. He has also been granted four patents.
Sanjeev Kumar Joshi
Dr. Sanjeev Kumar Joshi is an accomplished author and Assistant Professor, currently serving as Head of the Department of Mechanical Engineering at Uttaranchal University. With a background in M. Tech from DIT University and a PhD from his current institution, Dr. Joshi combines academic rigor with practical experience. His scholarly contributions span various facets of mechanical engineering, reflecting his expertise and dedication to advancing the field through research and education.
Ajay Suryavanshi
Dr. Ajay Suryavanshi received his B.Tech. in Mechanical Engineering from the Institute of Engineering and Technology, Lucknow in 1997. He completed his M.E. in Mechanical Engineering from Birla Institute of Technology and Science, Pilani, India in 2000. He completed his Ph.D. in the Mechanical Engineering Department, Motilal Nehru National Institute of Technology (MNNIT), Allahabad, India. He is currently working as an Associate Professor in the Mechanical Engineering Department of Bundelkhand Institute of Engineering and Technology, Jhansi. He has seventeen years of teaching experience. His research interests include unconventional machining processes, finite element analysis in manufacturing, composite materials, and renewable energy systems.
Parul Gupta
Dr. Parul Gupta is a distinguished academician, researcher, and educational administrator. He is the Director of the Global Institute of Technology & Management, Gurgaon, Haryana, India. Having a remarkable experience of 24 years, Dr. Parul served at some reputed Universities and Institutions as an Hon’ble Provost/PVC/Director in India. Besides this, Dr. Gupta has also contributed as a potential Researcher and Administrator during his 24 years of Academic Journey. He completed his B.E. in 1999 from Bangalore Institute of Technology, Bangalore while M. Tech (2006) and Ph.D., (2014) from M.N.N.I.T, Allahabad, in Mechanical Engineering as a specialization. His research interests include product design, machine design, smart materials, Additive manufacturing, Industry 4.0, and renewable energy systems. He holds several patents and published a good number of research papers in SCI Journals.
Muneesh Sethi
Dr. Muneesh Sethi is the Dean (R&D) at CORE University and he has a long distinguished academic career spanning over 22 years in teaching, research, and industry. He earned his doctorate in Mechanical Engineering from NIT Hamirpur. He has been working as a Professor & Dean of engineering since 2013. He taught a wide range of subjects for undergraduate, postgraduate, and doctorate students related to mechanical engineering. He has done extensive work in the field of renewable energy and established a center of excellence in renewable energy. His research work is concentrated on the Thermohydraulic Performance of Solar Air Heaters and published more than 60 research articles in national/international journals.