Effects of thermal conductivity and geometry of materials on the temperature variation in packed bed solar air heater
Purchase on Springer.com
$39.95 / €34.95 / £29.95*
Rent the article at a discountRent now
* Final gross prices may vary according to local VAT.
The efficiency of energy collection of a flat plate type of solar air heater is low because of the large thermal losses and low heat transfer coefficient between the absorber plate and the air flowing in the duct. Packed beds have been successfully employed for the enhancement of the heat transfer coefficients in solar air heaters and such air heaters can be used for drying agricultural produce and space heating as well. This article deals with the theoretical investigation on the effects of thermal conductivity of material and geometry of a screen on the temperature variation in woven wire screen packed bed solar air heater. Theoretical results have been compared with the experimental results reported earlier by other researchers and found to match reasonably well with them. It has been found that the thermal performance depends upon a little on the thermal conductivity of screen material. Instead, it depends more on the geometry and an extinction coefficients of the matrix. A low value of extinction coefficient is desirable for maximum absorption of solar radiations and minimum thermal losses. The numerical method of analysis used here is based on finite difference approximation. The finite difference equations have been solved through a computer program in C++.
- Panwar NL, Kaushik SC, Kothari S. Role of renewable energy sources in environmental protection: a review. Renew Sustain Energy Rev. 2011;15:1513–24. CrossRef
- Gupta MK, Kaushik SC. Exergy performance evaluation and parametric studies of solar air heater. Energy. 2008;33:1691–702. CrossRef
- Gupta MK, Kaushik SC. Performance evaluation of solar air heater for various artificial roughness geometries based on energy, effective and exergy efficiencies. Renew Energy. 2009;34:465–76. CrossRef
- Rathore NS, Panwar NL. Experimental studies on hemi cylindrical walk-in type solar tunnel dryer for grape drying. Appl Energy. 2010;87:2764–7. CrossRef
- Hatami N, Bahadorinejad M. Experimental determination of natural convection heat transfer coefficient in a vertical flat-plate solar air heater. Sol Energy. 2008;82:903–10. CrossRef
- Tyagi VV, Pandey AK, Kaushik SC, Tyagi SK. Thermal performance evaluation of a solar air heater with and without thermal energy storage- An experimental study. J Therm Anal Calorim. 2011. doi:10.1007/s10973-011-1617-3.
- Coppage JE, London AL. Heat transfer and flow friction characteristics of porous media. Chemical Eng Prog. 1956;52:57–63.
- Tong LS, London AL. Heat transfer and flow friction characteristics of cover screen and cross rod matrices. Trans ASME. 1957;79:1558–70.
- Kays WM, London AL. Compact heat exchangers. New York: McGraw-Hill; 1964.
- Chiou JP, El-Wakil MM, Duffie JA. A slit and expanded aluminium foil matrix solar collector. Sol Energy. 1965;9:73–80. CrossRef
- Hamid YH, Beckman WA. Performance of air-cooled radiatively heated screen matrices. J Eng Power. 1971;93:221–4. CrossRef
- Choudhary C, Garg HP. Performance of air-heating collectors with packed air flow passage. Sol Energy. 1993;50:205–21. CrossRef
- Ahmad A, Saini JS, Verma HK. Effect of geometrical and thermophysical characteristics of bed materials on the enhancement of thermal performance of packed bed solar air heaters. Energy Convers Manag. 1995;36:1185–95. CrossRef
- Demirel Y, Sharma RN, Al-Ali HH. On the effective heat transfer parameters in a packed bed. Int J Heat Mass Transf. 2000;43:327–32. CrossRef
- Thakur NS, Saini JS, Solanki SC. Heat transfer and friction factor correlations for packed bed solar air heater for a low porosity system. Sol Energy. 2003;74:319–29. CrossRef
- Ozturk H, Demirel Y. Exergy-based performance analysis of packed bed solar air heaters. Int J Energy Res. 2004;28:423–32. CrossRef
- Mittal MK, Varshney L. Optimal thermo-hydraulic performance of a wire mesh packed bed solar air heater. Sol Energy. 2006;80:1112–20. CrossRef
- Ramadan MRI, El-Sebaii AA, Aboul-Enein S, El-Bialy E. Thermal performance of a packed bed double-pass solar air heater. Energy. 2007;32:1524–35. CrossRef
- Prasad SB, Saini JS, Singh KM. Investigation of heat transfer and friction characteristics of packed bed solar air heater using wire mesh as packing material. Sol Energy. 2009;83:773–83. CrossRef
- Makkawi Y, Demirel Y, Al-Ali HH. Numerical analysis of convection heat transfer in a rectangular packed duct with asymmetric heating. Energy Convers Manag. 1998;39:455–63. CrossRef
- Demirel Y, Abu-Al-Saud BA, Al-Ali HH, Makkawi Y. Packing size and shape effects on forced convection in large rectangular packed ducts with asymmetric heating. Int J Heat Mass Transf. 1999;42:3267–77. CrossRef
- Demirel Y. Thermodynamic optimization of convective heat transfer in a packed duct. Energy. 1995;20:959–67. CrossRef
- Demirel Y, Al-Ali HH. Thermodynamic analysis of convective heat transfer in a packed duct with asymmetrical wall temperatures. Int J Heat Mass Transf. 1997;40:1145–53. CrossRef
- Demirel Y, Kahraman R. Thermodynamic analysis of convective heat transfer in an annular packed bed. Int J Heat Fluid Flow. 2000;21:442–8. CrossRef
- Sparrow EM, Tien KK. Forced convection heat transfer at an inclined and yawed square plate–application to solar collectors. Heat Transf Trans ASME. 1977;99:507. CrossRef
- Swinbank WC. Long wave radiation from clear skies. Q J R Meteorol Soc. 1964;90:488–93. CrossRef
- Kays WM. Convective heat and mass transfer. New York: McGraw-Hill; 1996.
- Yagi S, Kunii D. Studies on effective thermal conductivities in packed beds. AIChE J. 1957;3:373–81. CrossRef
- Ranz WE. Fixation and transfer coefficients for single particles and packed beds. Chem Eng Prog. 1952;48:247–53.
- Hasatani M, Itaya Y, Adachi K. Heat transfer and thermal storage characteristics of optically semi-transparent material packed bed solar air heaters. In: Current research in HMT, I.I.T., Madras, India; 1985:61–70.
- Ahmad A. Studies on the performance of packed bed solar air heaters. Ph.D thesis, University of Roorkee, India; 1995.
- Demirel Y, Kunc S. Thermal performance study of a solar air heater with packed flow passage. Energy Convers Manag. 1987;27:317–25. CrossRef
- Effects of thermal conductivity and geometry of materials on the temperature variation in packed bed solar air heater
Journal of Thermal Analysis and Calorimetry
Volume 111, Issue 1 , pp 839-847
- Cover Date
- Print ISSN
- Online ISSN
- Springer Netherlands
- Additional Links
- Packed bed solar air heater
- Thermal conductivity
- Extinction coefficient
- Screen geometry
- Finite difference approximation
- Industry Sectors
- Author Affiliations
- 1. Department of Mechanical & Automation Engineering, Indira Gandhi Institute of Technology, GGS Indraprastha University, Delhi, 110006, India
- 2. Department of Renewable Energy Sources, College of Technology and Engineering, Maharana Pratap University of Agriculture and Technology, Udaipur, Rajasthan, 313001, India