TY - GEN
T1 - DIRECT NUMERICAL SIMULATIONS OF THREE DIMENSIONAL SECONDARY STREAMING OF OSCILLATING FLOWS THROUGH A CYLINDRICAL PELLET
AU - Su, Yan
AU - Sun, Liyong
N1 - Funding Information:
This study was supported from the sponsorship of Science and Technology Development Fund, Macao SAR with the project No. FDCT/0115/2018/A3 and from University of Macau No. MYRG2017-00003-FST and MYRG2018-00018-FST.
Publisher Copyright:
© 2021 Begell House Inc.. All rights reserved.
PY - 2021
Y1 - 2021
N2 - Oscillating flows past a cylindrical pellet with endplates are simulated by the three dimensional (3D) direct numerical simulation (DNS) method. Partial sums of the Fourier series is applied to analyze the harmonic velocity fields obtained by the DNS method. The 3D secondary streaming (SS) and the gap averaged SS are visualized by streak lines. The results show that the gap averaged SS patterns are eight closed two dimensional (2D) recirculations. However, the SS flows are 3D spirals. The present 3D SS patterns are compared favorably with previous experimental study. For 3D patterns, fluid particles near the endplates are attracted into the spirals toward the mid-plane and the two endplates. Various governing parameters such as aspect ratio, Keulegan-Carpenter number, and Stokes number are investigated. The thickness of inner layer of the recirculations of the 2D gap averaged SS and the size of the 3D SS spirals near the cylinder wall decrease with the gap distance, the Keulegan-Carpenter number, and the Stokes number due to thinner viscous layers. The 3D spiral numbers increase with Stokes number due to turbulence effects.
AB - Oscillating flows past a cylindrical pellet with endplates are simulated by the three dimensional (3D) direct numerical simulation (DNS) method. Partial sums of the Fourier series is applied to analyze the harmonic velocity fields obtained by the DNS method. The 3D secondary streaming (SS) and the gap averaged SS are visualized by streak lines. The results show that the gap averaged SS patterns are eight closed two dimensional (2D) recirculations. However, the SS flows are 3D spirals. The present 3D SS patterns are compared favorably with previous experimental study. For 3D patterns, fluid particles near the endplates are attracted into the spirals toward the mid-plane and the two endplates. Various governing parameters such as aspect ratio, Keulegan-Carpenter number, and Stokes number are investigated. The thickness of inner layer of the recirculations of the 2D gap averaged SS and the size of the 3D SS spirals near the cylinder wall decrease with the gap distance, the Keulegan-Carpenter number, and the Stokes number due to thinner viscous layers. The 3D spiral numbers increase with Stokes number due to turbulence effects.
UR - http://www.scopus.com/inward/record.url?scp=85137455678&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85137455678&partnerID=8YFLogxK
U2 - 10.1615/TFEC2021.cnd.31920
DO - 10.1615/TFEC2021.cnd.31920
M3 - Conference contribution
AN - SCOPUS:85137455678
T3 - Proceedings of the Thermal and Fluids Engineering Summer Conference
SP - 201
EP - 210
BT - 5th-6th Thermal and Fluids Engineering Conference, TFEC 2021
PB - Begell House Inc.
T2 - 5th-6th Thermal and Fluids Engineering Conference, TFEC 2021
Y2 - 26 May 2021 through 28 May 2021
ER -