Mechanism of momentum transportation in the intermediate wake of a heated cylinder
Measurements in the wake of a heated cylinder are made by a thermo-anemometer. The purpose is to make clear the effects of buoyancy of heated cylinder on the mechanism of momentum transportation in the wake. In this work, the diameter of the cylinder is D=0.030 m, Reynolds numbers ReD=U0D/ν are 3000...
| Main Authors: | , , |
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| Format: | Article |
| Language: | Japanese |
| Published: |
The Japan Society of Mechanical Engineers
2020-02-01
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| Series: | Nihon Kikai Gakkai ronbunshu |
| Subjects: | |
| Online Access: | https://www.jstage.jst.go.jp/article/transjsme/86/883/86_19-00367/_pdf/-char/en |
| _version_ | 1798015122807980032 |
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| author | Hideaki WATANABE Hideharu MAKITA Makoto TAGO |
| author_facet | Hideaki WATANABE Hideharu MAKITA Makoto TAGO |
| author_sort | Hideaki WATANABE |
| collection | DOAJ |
| description | Measurements in the wake of a heated cylinder are made by a thermo-anemometer. The purpose is to make clear the effects of buoyancy of heated cylinder on the mechanism of momentum transportation in the wake. In this work, the diameter of the cylinder is D=0.030 m, Reynolds numbers ReD=U0D/ν are 3000～10000, Δθ=0～225 K and Richardson number RiD=gβΔθD/U02=0～0.0568. The causes of antisymmetric configuration in the horizontal heated cylinder wake are the downward motion of the vortex streets in upstream sections, and in downstream sections, the upward stretching of upper side vortices due to buoyancy. The antisymmetric wake configuration, caused by heating, affects on the mechanism of momentum transportation. In the upstream sections, velocity fluctuation at the vortex shedding frequency fc plays an important role in the momentum transportation, but in the downstream sections, the breakdown of the shedding vortices are accelerated by heating, and the main contribution to the momentum transportation supersedes by velocity fluctuations at frequencies lower than fc. |
| first_indexed | 2024-04-11T15:29:30Z |
| format | Article |
| id | doaj.art-ab3415f7757947a8953a1fa176b4678b |
| institution | Directory Open Access Journal |
| issn | 2187-9761 |
| language | Japanese |
| last_indexed | 2024-04-11T15:29:30Z |
| publishDate | 2020-02-01 |
| publisher | The Japan Society of Mechanical Engineers |
| record_format | Article |
| series | Nihon Kikai Gakkai ronbunshu |
| spelling | doaj.art-ab3415f7757947a8953a1fa176b4678b2022-12-22T04:16:11ZjpnThe Japan Society of Mechanical EngineersNihon Kikai Gakkai ronbunshu2187-97612020-02-018688319-0036719-0036710.1299/transjsme.19-00367transjsmeMechanism of momentum transportation in the intermediate wake of a heated cylinderHideaki WATANABE0Hideharu MAKITA1Makoto TAGO2Department of Mechanical Engineering and Robotics, Mechanical System Course, National Institute of Technology, Akita CollegeDepartment of Mechanical Engineering, Toyohashi University of TechnologyDepartment of Mechanical Engineering, Akita UniversityMeasurements in the wake of a heated cylinder are made by a thermo-anemometer. The purpose is to make clear the effects of buoyancy of heated cylinder on the mechanism of momentum transportation in the wake. In this work, the diameter of the cylinder is D=0.030 m, Reynolds numbers ReD=U0D/ν are 3000～10000, Δθ=0～225 K and Richardson number RiD=gβΔθD/U02=0～0.0568. The causes of antisymmetric configuration in the horizontal heated cylinder wake are the downward motion of the vortex streets in upstream sections, and in downstream sections, the upward stretching of upper side vortices due to buoyancy. The antisymmetric wake configuration, caused by heating, affects on the mechanism of momentum transportation. In the upstream sections, velocity fluctuation at the vortex shedding frequency fc plays an important role in the momentum transportation, but in the downstream sections, the breakdown of the shedding vortices are accelerated by heating, and the main contribution to the momentum transportation supersedes by velocity fluctuations at frequencies lower than fc.https://www.jstage.jst.go.jp/article/transjsme/86/883/86_19-00367/_pdf/-char/enwakeheated cylinderthermo-anemometryflow measurementsmomentum transportation |
| spellingShingle | Hideaki WATANABE Hideharu MAKITA Makoto TAGO Mechanism of momentum transportation in the intermediate wake of a heated cylinder Nihon Kikai Gakkai ronbunshu wake heated cylinder thermo-anemometry flow measurements momentum transportation |
| title | Mechanism of momentum transportation in the intermediate wake of a heated cylinder |
| title_full | Mechanism of momentum transportation in the intermediate wake of a heated cylinder |
| title_fullStr | Mechanism of momentum transportation in the intermediate wake of a heated cylinder |
| title_full_unstemmed | Mechanism of momentum transportation in the intermediate wake of a heated cylinder |
| title_short | Mechanism of momentum transportation in the intermediate wake of a heated cylinder |
| title_sort | mechanism of momentum transportation in the intermediate wake of a heated cylinder |
| topic | wake heated cylinder thermo-anemometry flow measurements momentum transportation |
| url | https://www.jstage.jst.go.jp/article/transjsme/86/883/86_19-00367/_pdf/-char/en |
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