Numerical study on heat transfer and nanofluid flow in pipes fitted with different dimpled spiral center plate

Abstract

This research presents a numerical study on heat transfer and flow characteristics for two pipe fitted by two different dimpled spiral center plate by utilizing Al 2 O 3 , CuO and TiO 2 nanofluids as cooling fluids. Considering the effect of dimples arrangement, nanoparticle diameter d p , nanofluids volume fraction φ and also the heat transfer coefficient, thermal property. Average amount of entropy generation S a and maximum local temperature of wall T max were discussed. Results demonstrate that the in-line arrangement geometry behaves better in compare to the geometry with the staggered arrangement. 47.3% is the maximum enhancement of convection heat transfer for the in-line arrangement in compare with the smooth spiral central plate with base flow. Using nanofluids improved the wall temperature distribution, and using nanofluid caused great improvement in thermal conductivity with a little raise in dynamic viscosity. Using nanofluids caused a considerable decrease in S a , which also as the result of rising φ, and S a maximum reduction is about 24.7%. T max considerably declines by using nanofluids and enhanced by a rising φ. Also, CuO-water nanofluid has a better effect on heat transfer and flow characteristics than the other nanofluids.

Development of a neural architecture to predict the thermal conductivity of nanofluids

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Effective Thermal Conductivity of Nanofluids Containing Silicon Dioxide or Zirconium Dioxide Nanoparticles Dispersed in a Mixture of Water and Glycerol

“…The application of nanofluids is highly versatile due to their extensive range of properties and tailorability. The classical field of potential application is the use of nanofluids as heat transfer fluids in heat exchangers [2][3][4][5]. Since the effective thermal conductivity of nanofluids as one key thermophysical property in heat engineering is typically larger than the thermal conductivity of the particle-free base fluids, the overall heat transfer can be increased [5].…”

Numerical study of the effects of geometric parameters and nanofluid properties on heat transfer and pressure drop in helical tubes

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