Thermal Efficiency Enhancement in Solar Collectors Using Porous Duct Absorbers for a Solar Dryer

Authors

  • Suradech Sinjapo Department of Mechanical Engineering, Faculty of Engineering and Technology, Rajamangala University of Technology Isan, Nakhon Ratchasima
  • Jattupon Pongkun Department of Railway Systems, Faculty of Railway Systems and Transportation, Rajamangala University of Technology Isan, Nakhon Ratchasima
  • Pilin Hankhuntod Department of Railway Systems, Faculty of Railway Systems and Transportation, Rajamangala University of Technology Isan, Nakhon Ratchasima
  • Niwat Ketchat Department of Energy and Air Conditioning Engineering, Faculty of Engineering and Technology, Rajamangala University of Technology Isan, Nakhon Ratchasima

DOI:

https://doi.org/10.14456/jeit.2026.18

Keywords:

Thermal Efficiency, Solar Collectors, Porous Duct Absorbers

Abstract

The objective of this research was to investigate the influence of porous media on the thermal efficiency of solar collectors using porous duct absorbers. The experiments were conducted under two configurations: 1) a flat-plate solar collector and 2) a collector equipped with porous duct absorbers. SUS 304 stainless steel wire mesh was used as the porous medium. Four pore densities of 12, 16, 20, and 24 pores per inch (PPI) were examined. The height ratio and pitch ratio were fixed at 1 and 2, respectively. The incident solar radiation intensities were set at 600, 800, and 1,000 W/m². Three mass flow rates of air consisting of 0.010, 0.015 and 0.020 kg/s were investigated. The experimental results revealed that the collector integrated with porous duct absorbers exhibited significantly higher thermal efficiency than the flat-plate collector under all operating conditions. Thermal efficiency increased with increasing air mass flow rate due to enhanced convective heat transfer. The maximum thermal efficiency of 54.96% was achieved at PPI = 12 and an air mass flow rate of 0.02 kg/s and an incident radiation intensity of 1,000 W/m². In addition, the porous duct absorbers effectively reduced the moisture content of the dried product. These findings indicate that porous duct absorbers have strong potential for improving solar drying systems and low-temperature heat exchange applications.

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Published

2026-06-29

How to Cite

[1]
S. . Sinjapo, J. . Pongkun, P. . Hankhuntod, and N. Ketchat, “Thermal Efficiency Enhancement in Solar Collectors Using Porous Duct Absorbers for a Solar Dryer”, JEIT, vol. 4, no. 3, pp. 48–57, Jun. 2026.