Author:
H. Ghahramani Nickan,Sharp Martin,Morgan Michael,Seddighi Mehdi
Abstract
The use of a pulsed laser system to manufacture parallel streamwise riblets on the plates of a heat exchanger is reported. There are certain laser system elements that can influence the quality of a micrometre texture geometry; among these, there was a focus on laser incubation effect on obtaining greater depth of the riblets. Surface roughness was always considered to keep the heat transfer efficiency high. The heat exchanging process was measured in two flow regimes: laminar and turbulent. In laminar flow, the surface texture slightly deteriorated the heat transfer rate. However, small improvement in the heat transfer rate was observed in turbulent flow.
Reference16 articles.
1. Nishida A, Nakatsuji K, Hagiwara Y. Direct numerical simulation of the effects of slip velocity of wavy walls on turbulent heat transfer and drag. In: Proceedings of the 9th International Symposium on Turbulence and Shear Flow Phenomena. Danbury, USA. 2015. pp. 1-6
2. Bechert D, Bruse M, Hage W, Van Der Hoeven J, Hoppe G. Experiments on drag-reducing surfaces and their optimization with an adjustable geometry. Journal of Fluid Mechanics. 1997;338:59-87
3. Dumanis M. First course in turbulence: Dean Young. Boston Review. 1999;24(5):66
4. Kline S, Reynolds W, Schraub F, Runstadler P. The structure of turbulent boundary layers. Journal of Fluid Mechanics. 1967;30(4):741-773
5. Zhu Z, Li J, Peng H, Liu D. Nature-inspired structures applied in heat transfer enhancement and drag reduction. Micromachines. 2021;12:6