Document Type : full paper
Authors
1
MSc Student, Department of Mechanical Engineering, Islamic Azad University, Takestan, Iran
2
Assistant Professor, Department of Mechanical Engineering, Islamic Azad University, Takestan, Iran
3
Assistant Professor, Department of Physics, Islamic Azad University, Takestan, Iran
Abstract
The aim of this study was to investigate carbon nanostructures, including carbon nanotubes, graphene and graphene- iron oxide hybrid to use in shell & tube heat exchanger in order to improve the heat transfer effect. First try to build a stable nano-fluid and thermo-physical properties such as viscosity and thermal conductivity are examined. According to surveys conducted, nano-fluid density changes is very low and ignorable but However, nano-fluid viscosity changes with increasing concentrations of nano-fluid is associated with a significant increase, but also at low concentrations of particles increase the viscosity is negligible. According to surveys increase of 31%, 20% and 26% in water-based nano-fluid and 38%, 29% and 34% ethylene glycol nano-base fluid in thermal conductivity at 40 oC for carbon nanotubes nano-fluid, graphene and hybrid graphene-oxide is obtained. Among reviewed nano-fluid greatest improvement in the coefficient of performance is in fluids containing nano-particles of iron oxide-graphene hybrid that at 80 oC, 21% and 15%, respectively, based on water and glycol recovery is achieved
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