A detailed review on research, technology, configurations and application of wire ribs as artificial roughness in rectangular solar air heater duct

2021 ◽  
pp. 095440892199514
Author(s):  
Mukesh Kumar Sahu ◽  
Abhishek Priyam ◽  
Shivam Mishra ◽  
Pardeep Bishnoi
Keyword(s):  
Heat Transfer ◽  
Performance Enhancement ◽  
Roughness Element ◽  
Solar Air Heater ◽  
Artificial Roughness ◽  
Flow Process ◽  
Holistic View ◽  
Air Heater ◽  
Research Technology ◽  
Interesting Area

Use of artificial roughness in the duct of solar air heater (SAH) has been an interesting area of research during the last few decades. In present review article a holistic view about application of circular shape wire ribs as roughness element and its different geometry on the absorber plate of SAH duct for performance enhancement has been done. This article, reported in details numerous experimental as well as analytical studies for rib roughened SAHs which have been carried out by different researchers positively. Correlations for heat transfer and friction factor, developed by various investigators for different artificially roughened solar air heaters (SAHs) geometry have been reported in chronological order and in well tabulated form. The roughness and operating parameters into which investigators have obtained their maximum performances of SAHs have also been presented separately in the table. Effects of various rib roughness parameters on heat transfer and fluid flow process are also discussed in details.

Effect of Gap Position in Broken V-rib Roughness Combined with Staggered Rib on Thermohydraulic Performance of Solar Air Heater

Green ◽  
2011 ◽  
Vol 1 (4) ◽  
Author(s):  
Anil K. Patil ◽  
J. S. Saini ◽  
K. Kumar
Keyword(s):  
Heat Transfer ◽  
Reynolds Number ◽  
Hydraulic Performance ◽  
Solar Air Heater ◽  
Artificial Roughness ◽  
Effective Technique ◽  
Air Heater ◽  
Flow Through ◽  
Absorber Surface

AbstractApplication of artificial roughness on underside of absorber surface has been found to be effective technique to improve thermo hydraulic performance of solar air heaters. In progression to the previous researches, the present study discloses the effect of broken V-rib roughness combined with staggered ribs on heat transfer and friction in a flow through artificially roughened solar air heater duct. The experimentations were performed to collect the data on heat transfer and friction by varying the Reynolds number (Re) between 3000 and 17,000, relative gap position (

scholarly journals Enhanced Solar Air Heaters For Crop Drying

2021 ◽  
pp. 1-5
Author(s):  
Kamlesh Sahu ◽  
◽  
Gyaneshwar Sanodiya ◽  
Keyword(s):  
Heat Transfer ◽  
Heat Transfer Coefficient ◽  
Transfer Coefficient ◽  
Roughness Element ◽  
Air Flow ◽  
Thermal Capacity ◽  
Solar Air Heater ◽  
Artificial Roughness ◽  
Transfer Coefficients ◽  
Absorber Plate

Solar air heaters are placed on farms to provide heat for the drying of grain and crop harvesting and harvesting. The results of the thermal study showed that solar air heaters are capable of providing a sufficient increase in air temperature under the majority of crop drying circumstances studied. The restricted thermal capacity of air, as well as the low heat transfer coefficient between the absorber plate and the air flow via the ducting system, both contribute to the overall thermal efficiency of solar air heaters. Solar air heaters must be more efficient in order to be more affordable. This may be accomplished by increasing the heat transfer coefficient between the absorber plate and the air flow passing through the duct. More heat transfer coefficients can be increased by using either active or passive approaches. In most situations, it may be cost-effective to use solar air heaters and incorporate artificial roughness on the absorber plate. The rate of heat transmission from the solar air heater’s duct to the fluid flow may be increased by creating artificial roughness on the surface of the duct. The study focused on several roughness element geometries for solar air heater ducts, and the results indicated that there is a link between the two. This paper attempts to find ways to artificially increase the heat transfer capacity of solar air heaters’ ducts by using element geometries which have been utilised in solar air heaters’ heat transfer devices.

Thermal performance enhancement of flat plate solar air heater using transverse U-shaped turbulator - A numerical study

2019 ◽  
Vol 13 (3) ◽  
pp. 5562-5587 ◽  
Author(s):  
M. S. Manjunath ◽  
R. Venkatesh ◽  
N. Madhwesh
Keyword(s):  
Heat Transfer ◽  
Flat Plate ◽  
Enhancement Factor ◽  
Performance Enhancement ◽  
Numerical Study ◽  
Solar Air Heater ◽  
Air Heater ◽  
Relative Pitch ◽  
Thermal Enhancement ◽  
Thermal Enhancement Factor

The aim of this study is to determine the effect of U-shaped rib turbulator on the flow and heat transfer characteristics of flat plate solar air heater using two dimensional CFD analysis. The analysis is carried out using the CFD software tool ANSYS Fluent for the flow Reynolds number ranging from 9000 to 21,000.The relative pitch(P/e) of the U-shaped rib is varied as 5, 10, 25 and 40 for a fixed relative rib height of 0.0421. It is shown that the U-shaped rib augments the Nusselt number by about 1.76 times while the friction factor increased by about 1.95 times with reference to smooth duct for a relative pitch of 10 and 5 respectively. The maximum thermal enhancement factor is obtained as 1.5 for the configuration of P/e=25. A comparative analysis of U-shaped rib with circular rib reveals that the U-shaped rib turbulator is found to be more effective in providing heat transfer enhancement and has about 15% higher thermal enhancement factor as compared to circular turbulator.

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.

Sign in / Sign up

Export Citation Format

Share Document