The Role of Nanoparticles and Different Tube Diameter on Thermal Performance in Shell and Helically Coiled Tube Heat Exchangers with Single Phase and Sub-cooled Boiling Flow

H Abazari Bahnemiri,A Zare-Shahabadi,S A A Mirjalily,S A A Oloomi

doi:10.5829/ijee.2021.12.04.10

Abstract

In the present research, effects of nanoparticles and changing of tube diameter have been scrutinized on heat transfer parameters in the shell and helically coiled tube heat exchanger. A CFD analysis and also a modeling of the mentioned heat exchager have carried out by writing a code in MATLAB software for two regimes involving forced convection heat trasnfer in single phase fluid flow and sub-cooled boiling. In the case under analysis, considered nanoparticles in this research was Nickel nanoparticles with 0.1 and 1% volumetric concentration. Based on the results, both going up of volume concentration of nanoparticles and increasing of tube diameter are cause to make better heat transfer parameters. In truth, heat transfer coefficient and Nusselt number have been enhanced by 0.1 and 1 % volumetric concentration of Nickel nanoparticles.

Highlights

In heat exchanger, heat transfers between fluids at different temperatures, and intersection between the fluids is a major parameter for enhancement of its efficiency
The heat transfer coefficient has been improvedequal 49.78% by enhancing of tube diameter and second, length of heat exchanger has been decreased by enhancing of tube diameter so that, the end of sub cooled boiling section has declined equal 37.12%
Coiled tube heat exchangers have been widely applied in many power conversion systems for their advantages, involving compactness and high efficiency in heat transfer

Summary

Introduction

Heat transfers between fluids at different temperatures, and intersection between the fluids is a major parameter for enhancement of its efficiency. Effects of nanoparticles and changing of tube diameter have been scrutinized on heat transfer parameters in the shell and helically coiled tube heat exchanger. The executed study efforts to s crutinize of effect of nanoparticles and altering of tube diameter on thermal characteristics in a heat exchanger with type of shell and helically coiled tube so that it is significant for special industries such as nuclear reactors, power plants, refrigeration and air conditioning systems, heat recovery systems.

Results

Conclusion