Article
Version 1
Preserved in Portico This version is not peer-reviewed
Drag Reduction by Dried Malted Rice Solutions in Pipe Flow
Version 1
: Received: 3 April 2024 / Approved: 3 April 2024 / Online: 4 April 2024 (15:57:41 CEST)
A peer-reviewed article of this Preprint also exists.
Watanabe, K.; Ogata, S. Drag Reduction by Dried Malted Rice Solutions in Pipe Flow. Liquids 2024, 4, 432-442. Watanabe, K.; Ogata, S. Drag Reduction by Dried Malted Rice Solutions in Pipe Flow. Liquids 2024, 4, 432-442.
Abstract
In this study, the friction factor of turbulent pipe flow for dried rice malt extract solutions is reduced experimentally to that of a Newtonian fluid. The friction factor is measured for four types of solutions at different culture times and concentrations. The results indicate that the experimental data points of the test solutions diverge from the maximum drag reduction asymptote at and above Re√f ≅ 200 and align parallel to those of Newtonian fluids. This drag reduction phenomenon differs from that of artificial high molecular polymer solutions. It is classified as a Type B drag reduction phenomenon of biopolymer solutions and fine solid particle suspensions. The order of drag reduction corresponds approximately to that of 5–50 ppm xanthan-gum solutions reported previously. Furthermore, the velocity profile in a turbulent pipe flow was predicted using a semi-theoretical equation, in which the friction factors were determined using the difference between the experimental results of the tested solutions and Newtonian fluids. The results indicate a more considerable thickening of the viscous sublayer in the turbulent pipe flow of the test solutions than that of Newtonian fluids.
Keywords
drag reduction; friction factor; velocity profile; biopolymer solutions
Subject
Engineering, Bioengineering
Copyright: This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
Comments (0)
We encourage comments and feedback from a broad range of readers. See criteria for comments and our Diversity statement.
Leave a public commentSend a private comment to the author(s)
* All users must log in before leaving a comment