scholarly journals Investigation on heat transfer enhancement in a circular pipe with artificial roughness

2020 ◽  
Vol 1683 ◽  
pp. 022105
Author(s):  
A P Koroleva ◽  
N V Kuzmenkov ◽  
M S Frantcuzov
Keyword(s):  
Heat Transfer ◽  
Heat Transfer Enhancement ◽  
Circular Pipe ◽  
Artificial Roughness ◽  
Transfer Enhancement

Use of artificial roughness to enhance heat transfer in solar air heaters – a review

2010 ◽  
Vol 21 (1) ◽  
pp. 35-51 ◽  
Author(s):  
Thakur Sanjay Kumar ◽  
N.S. Thakur ◽  
Anoop Kumar ◽  
Vijay Mittal
Keyword(s):  
Heat Transfer ◽  
Heat Transfer Enhancement ◽  
Heat Transfer Rate ◽  
Transfer Rate ◽  
Hydraulic Performance ◽  
Solar Air Heater ◽  
Artificial Roughness ◽  
Transfer Enhancement ◽  
Air Heater ◽  
Roughness Elements

Improvement in the thermo hydraulic performance of a solar air heater can be done by enhancing the heat transfer. In general, heat transfer enhancement techniques are divided into two groups: active and passive techniques. Providing an artificial roughness on a heat transferring surface is an effective passive heat transfer technique to enhance the rate of heat transfer to fluid flow. In this paper, reviews of various artificial roughness elements used as passive heat transfer techniques, in order to improve thermo hydraulic performance of a solar air heater, is done. The objective of this paper is to review various studies, in which different artificial roughness elements are used to enhance the heat transfer rate with little penalty of friction. Correlations developed by various researchers with the help of experimental results for heat transfer and friction factor for solar air heater ducts by taking different roughened surfaces geometries are given in tabular form. These correlations are used to predict the thermo hydraulic performance of solar air heaters having roughened ducts. The objective is to provide a detailed review on heat transfer enhancement by using an artificial roughness technique. This paper will be very helpful for the researchers who are researching new artificial roughness for solar air heater ducts to enhance the heat transfer rate and comparing with artificial roughness already studied by various researchers.

scholarly journals Heat Transfer and Fluid Flow Analysis for Turbulent Flow in Circular Pipe with Vortex Generator

2021 ◽  
Vol 3 (7) ◽  
Author(s):  
Kishor S. Rambhad ◽  
Vednath P. Kalbande ◽  
Manoj A. Kumbhalkar ◽  
Vivek W. Khond ◽  
Rahul A. Jibhakate
Keyword(s):  
Heat Transfer ◽  
Fluid Flow ◽  
Heat Transfer Enhancement ◽  
Flow Analysis ◽  
Vortex Generator ◽  
Circular Pipe ◽  
List Type ◽  
Transfer Enhancement ◽  
Performance Of Heat Transfer ◽  
Fluid Flow Analysis

Abstract The performance of heat transfer enhancement (HTE) using modified inserts (MIs) as a vortex generator in pipe flow and fluid flow analysis using computational fluid dynamics (CFD) are evaluated in this article. The MIs are fastened to the central rod, and the circular sections of the MIs touched the circular wall of the test pipe. Heat transfer and fluid flow analyses are carried out for the various pitch to diameter ratios (P/D) and angles of the MIs. P/D ratios of 3, 4 and 6 and MIs angles of 15°, 30°, 45°, 60° and 90° are considered for experimental analysis. CFD analysis is carried out for P/D ratios of 3, 4 and 6 and MIs angles of 30°, 45° and 90°. Nusselt number (Nu/Nus) and friction factor (f/fs) ratios are evaluated using the same Reynolds number between 8000 and 17,000 in the experimental study. The MIs encourage the wall and core fluid to be combined thus helps in HTE. It is found that, as the P/D ratio increases, the Nu/Nus and f/fs decrease. If the distance between the MIs increases, the mixing of fluid weakens. With decreasing the P/D ratio, Nu/Nus increases. Increased fluid mixing leads to a higher coefficient of heat transfer and higher values of pressure drop. A P/D ratio of 4 and MIs angle of 45° results in greater heat interaction than others. Finally, recommendations for the best P/D ratio and angles of MIs are made for improved HTE on fluid flow through a circular pipe. Article Highlights Modified inserts (MIs) are used inside the test pipe to check the heat transfer enhancement at various angles. Also, compared the performance with and without MIs. Fluid flow analysis is checked by CFD (Fluent) in Ansys software. Fluid flow patterns for various MIs angles and P/D ratios are compared.

Sign in / Sign up

Export Citation Format

Share Document