Volume 19, Issue 1 (January 2019)
Modares Mechanical Engineering 2019, 19(1): 53-62 |
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1- Department of Heat & Fluid, Mechanical Engineering Faculty, University of Kashan, Kashan, Iran , sheikhz@kashanu.ac.ir
2- Energy Research Center, University of Kashan, Kashan, Iran
3- Department of Energy Conversion, Mechanical Engineering Faculty, Tarbiat Modares University, Tehran, Iran
4- Department of Heat & Fluid, Mechanical Engineering Faculty, University of Kashan, Kashan, Iran
2- Energy Research Center, University of Kashan, Kashan, Iran
3- Department of Energy Conversion, Mechanical Engineering Faculty, Tarbiat Modares University, Tehran, Iran
4- Department of Heat & Fluid, Mechanical Engineering Faculty, University of Kashan, Kashan, Iran
Abstract: (8082 Views)
Today, increasing the efficiency and optimization of energy systems in terms of economic and environmental conditions is of particular importance. So far, several methods have been proposed to increase the heat transfer in thermal systems, including the use of nanofluids and types of fluid flow turbulators. In this research, the application of both nanofluid and twisted tape to improve the heat transfer coefficient were numerically investigated. Different turbulence models were used to simulate fluid turbulence. The results showed that increasing the nanoparticle volume fraction, reducing the twisting ratio, and increasing the Reynolds number resulted in an increase in heat transfer. By reducing the twisting ratio from 15 to 5, the heat transfer rate increases from 8-16%. With rising Reynolds number from 10,000 to 20,000, maximum temperature differences decreases by 4.5%. Moving downstream of the flow, the difference between the maximum temperature of the sections decreases. Increasing the heat transfer and intensifying the effects of the twisted tape to downward are the reasons for this decline.
Article Type: Original Research |
Subject:
Two & Multi Phase Flow
Received: 2018/04/17 | Accepted: 2018/09/17 | Published: 2019/01/1
Received: 2018/04/17 | Accepted: 2018/09/17 | Published: 2019/01/1
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