THE EFFECT OF VOLUME FRACTION OF SiO2 NANOPARTICLE ON FLOW AND HEAT TRANSFER CHARACTERISTICS IN A DUCT WITH CORRUGATED BACKWARD-FACING STEP

EKİCİLER R., Aydeniz E., ARSLAN K.

THERMAL SCIENCE, cilt.22, 2018 (SCI-Expanded) identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 22
  • Basım Tarihi: 2018
  • Doi Numarası: 10.2298/tsci1855435e
  • Dergi Adı: THERMAL SCIENCE
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Anahtar Kelimeler: backward-facing step, re-circulation region, corrugated duct, forced convection, nanofluid, NANOFLUID FLOW, FORCED-CONVECTION, MIXED CONVECTION, TRANSFER ENHANCEMENT, REYNOLDS-NUMBER, LAMINAR-FLOW
  • Gazi Üniversitesi Adresli: Evet

Özet

In this paper, flow and heat transfer characteristics of SiO2-water nanofluid flow over a corrugated backward-facing step are numerically investigated. The numerical study is performed by solving governing equations (continuity, momentum, and energy) with finite volume method. The duct inlet and step heights are 4.8 mm. The expansion ratio is 2. The upstream wall, L-w and downstream wall, L-d, lengths are 48 cm and 96 cm, respectively. The downstream wall of the duct is subjected to a constant and uniform heat flux of 2000 W/m(2). The ranges of the volume fraction of nanoparticles and Reynolds number are 0%-3.0% and 135-240, respectively. The effects of the volume fraction of nanoparticles on the average Nusselt number, average Darcy friction factor, and velocity distribution are investigated under laminar forced convective nanofluid flow condition. It is revealed that the nanoparticle volume fraction substantially influences the heat transfer and flow characteristics. The volume fraction of 3.0% shows the highest heat transfer performance.