{"created":"2023-06-20T15:12:58.683522+00:00","id":42862,"links":{},"metadata":{"_buckets":{"deposit":"efdd1346-4c65-42f9-bd1d-506029dea162"},"_deposit":{"created_by":1,"id":"42862","owners":[1],"pid":{"revision_id":0,"type":"depid","value":"42862"},"status":"published"},"_oai":{"id":"oai:jaxa.repo.nii.ac.jp:00042862","sets":["1887:1893","1896:1898:1913:1917"]},"author_link":["460822","460827","460826","460828","460823","460824","460821","460819","460820","460825"],"item_3_alternative_title_2":{"attribute_name":"その他のタイトル（英）","attribute_value_mlt":[{"subitem_alternative_title":"Transition process of boundary layers on a low-speed wind-tunnel contraction wall"}]},"item_3_biblio_info_10":{"attribute_name":"書誌情報","attribute_value_mlt":[{"bibliographicIssueDates":{"bibliographicIssueDate":"2003-06","bibliographicIssueDateType":"Issued"},"bibliographicVolumeNumber":"1462","bibliographic_titles":[{"bibliographic_title":"航空宇宙技術研究所報告"},{"bibliographic_title":"Technical Report of National Aerospace Laboratory","bibliographic_titleLang":"en"}]}]},"item_3_description_16":{"attribute_name":"抄録","attribute_value_mlt":[{"subitem_description":"低速風洞縮流胴に沿った境界層の遷移過程を可視化および熱線計測などにより実験的に研究した。縮流胴境界層の遷移過程は次のように幾つかの素過程に分けられる。レイノルズ数が低い場合、凹面領域にはゲルトラー不安定により、流れ方向に軸を持ち対になって回転する縦渦列が発生する。層流境界層はその縦渦列によって歪められて変曲点を持ち、2次不安定によって乱流へと遷移する。しかし、下流の凸面領域に至ると主流の加速によって境界層は再層流化され、縮流胴出口まで層流状態が維持される。レイノルズ数が高い場合、縮流胴入口における初期境界層はすでに乱流状態にあり、凹面領域を通過する間に境界層厚さはさらに増加するが、その下流の凸面領域では一旦層流化する。しかし、縮流胴出口付近において乱流斑点が自然発生することにより、境界層は再遷移する。測定部の主流流速を増加すると乱流斑点が発生する位置は上流側のより加速された領域へと移動する。乱流斑点は加速流中でも下流に向かって成長するので、レイノルズ数が高い場合には測定部の境界層が乱流になるのは避けられない。","subitem_description_type":"Abstract"}]},"item_3_description_17":{"attribute_name":"抄録（英）","attribute_value_mlt":[{"subitem_description":"The transition process of boundary layers on a low-speed wind-tunnel contraction wall was experimentally investigated using flow visualizations and hot-wire/hot-film measurements. The process has several classifications depending on the Reynolds number. For the low Reynolds number, a row of counter-rotating longitudinal vortex pairs is generated by the Gortler instability on the concave wall. The velocity profile of the laminar boundary layer distorted by the Gortler vortices has inflection points, and eventually the secondary high-shear-layer instability causes high-frequency velocity fluctuations. These growing disturbances lead the boundary layer to a turbulent state within the concave region of the contraction. However, the resultant turbulent boundary layer is laminarized by acceleration of the mean flow in the convex region free from centrifugal instability. For the higher Reynolds number, the initial boundary layer flow was already turbulent at the entrance of the contraction. The boundary-layer thickness increases downstream within the concave region. On the convex wall the turbulent boundary layer is laminarized; however, re-transition occurred with the naturally occurring turbulent spots under a favorable pressure gradient. With an increase in the mean velocity in the test section, the location of occurrence of spots moves forward into a more accelerated region. As the turbulent spots grow downstream even in the accelerated flow, the formation of a turbulent boundary layer is unavoidable on the test section wall at the higher Reynolds number.","subitem_description_type":"Other"}]},"item_3_description_32":{"attribute_name":"資料番号","attribute_value_mlt":[{"subitem_description":"資料番号: AA0046106000","subitem_description_type":"Other"}]},"item_3_description_33":{"attribute_name":"レポート番号","attribute_value_mlt":[{"subitem_description":"レポート番号: NAL TR-1462","subitem_description_type":"Other"}]},"item_3_publisher_8":{"attribute_name":"出版者","attribute_value_mlt":[{"subitem_publisher":"航空宇宙技術研究所"}]},"item_3_publisher_9":{"attribute_name":"出版者（英）","attribute_value_mlt":[{"subitem_publisher":"National Aerospace Laboratory (NAL)"}]},"item_3_source_id_21":{"attribute_name":"ISSN","attribute_value_mlt":[{"subitem_source_identifier":"1347-4588","subitem_source_identifier_type":"ISSN"}]},"item_3_source_id_24":{"attribute_name":"書誌レコードID","attribute_value_mlt":[{"subitem_source_identifier":"AN00311347","subitem_source_identifier_type":"NCID"}]},"item_3_text_6":{"attribute_name":"著者所属","attribute_value_mlt":[{"subitem_text_value":"航空宇宙技術研究所 流体科学研究センター"},{"subitem_text_value":"青山学院大学 大学院"},{"subitem_text_value":"航空宇宙技術研究所 流体科学研究センター"},{"subitem_text_value":"航空宇宙技術研究所 流体科学研究センター"},{"subitem_text_value":"青山学院大学 理工学部"}]},"item_3_text_7":{"attribute_name":"著者所属（英）","attribute_value_mlt":[{"subitem_text_language":"en","subitem_text_value":"National Aerospace Laboratory Fluid Science Research Center"},{"subitem_text_language":"en","subitem_text_value":"Aoyama Gakuin University Graduate School"},{"subitem_text_language":"en","subitem_text_value":"National Aerospace Laboratory Fluid Science Research Center"},{"subitem_text_language":"en","subitem_text_value":"National Aerospace Laboratory Fluid Science Research Center"},{"subitem_text_language":"en","subitem_text_value":"Aoyama Gakuin University College of Science and Engineering"}]},"item_creator":{"attribute_name":"著者","attribute_type":"creator","attribute_value_mlt":[{"creatorNames":[{"creatorName":"西沢, 啓"}],"nameIdentifiers":[{}]},{"creatorNames":[{"creatorName":"側垣, 正"}],"nameIdentifiers":[{}]},{"creatorNames":[{"creatorName":"高木, 正平"}],"nameIdentifiers":[{}]},{"creatorNames":[{"creatorName":"徳川, 直子"}],"nameIdentifiers":[{}]},{"creatorNames":[{"creatorName":"三栖, 功"}],"nameIdentifiers":[{}]},{"creatorNames":[{"creatorName":"Nishizawa, Akira","creatorNameLang":"en"}],"nameIdentifiers":[{}]},{"creatorNames":[{"creatorName":"Sobagaki, Tadashi","creatorNameLang":"en"}],"nameIdentifiers":[{}]},{"creatorNames":[{"creatorName":"Takagi, Shohei","creatorNameLang":"en"}],"nameIdentifiers":[{}]},{"creatorNames":[{"creatorName":"Tokugawa, Naoko","creatorNameLang":"en"}],"nameIdentifiers":[{}]},{"creatorNames":[{"creatorName":"Misu, Isao","creatorNameLang":"en"}],"nameIdentifiers":[{}]}]},"item_files":{"attribute_name":"ファイル情報","attribute_type":"file","attribute_value_mlt":[{"accessrole":"open_date","date":[{"dateType":"Available","dateValue":"2020-01-28"}],"displaytype":"detail","filename":"naltr0001462.pdf","filesize":[{"value":"3.8 MB"}],"format":"application/pdf","licensetype":"license_note","mimetype":"application/pdf","url":{"label":"naltr0001462.pdf","url":"https://jaxa.repo.nii.ac.jp/record/42862/files/naltr0001462.pdf"},"version_id":"1a4278fb-9a66-468c-ad6d-3f4613f42931"}]},"item_keyword":{"attribute_name":"キーワード","attribute_value_mlt":[{"subitem_subject":"低速風洞","subitem_subject_scheme":"Other"},{"subitem_subject":"層流境界層","subitem_subject_scheme":"Other"},{"subitem_subject":"乱流境界層","subitem_subject_scheme":"Other"},{"subitem_subject":"低Reynolds数","subitem_subject_scheme":"Other"},{"subitem_subject":"圧力分布","subitem_subject_scheme":"Other"},{"subitem_subject":"流れの可視化","subitem_subject_scheme":"Other"},{"subitem_subject":"安定性","subitem_subject_scheme":"Other"},{"subitem_subject":"熱線風速計","subitem_subject_scheme":"Other"},{"subitem_subject":"熱フィルム風速計","subitem_subject_scheme":"Other"},{"subitem_subject":"研究開発","subitem_subject_scheme":"Other"},{"subitem_subject":"速度分布","subitem_subject_scheme":"Other"},{"subitem_subject":"遷移過程","subitem_subject_scheme":"Other"},{"subitem_subject":"low speed wind tunnel","subitem_subject_language":"en","subitem_subject_scheme":"Other"},{"subitem_subject":"laminar boundary layer","subitem_subject_language":"en","subitem_subject_scheme":"Other"},{"subitem_subject":"turbulent boundary layer","subitem_subject_language":"en","subitem_subject_scheme":"Other"},{"subitem_subject":"low Reynolds number","subitem_subject_language":"en","subitem_subject_scheme":"Other"},{"subitem_subject":"pressure distribution","subitem_subject_language":"en","subitem_subject_scheme":"Other"},{"subitem_subject":"flow visualization","subitem_subject_language":"en","subitem_subject_scheme":"Other"},{"subitem_subject":"stability","subitem_subject_language":"en","subitem_subject_scheme":"Other"},{"subitem_subject":"hot-wire anemometer","subitem_subject_language":"en","subitem_subject_scheme":"Other"},{"subitem_subject":"hot-film anemometer","subitem_subject_language":"en","subitem_subject_scheme":"Other"},{"subitem_subject":"research and development","subitem_subject_language":"en","subitem_subject_scheme":"Other"},{"subitem_subject":"velocity distribution","subitem_subject_language":"en","subitem_subject_scheme":"Other"},{"subitem_subject":"transition process","subitem_subject_language":"en","subitem_subject_scheme":"Other"}]},"item_language":{"attribute_name":"言語","attribute_value_mlt":[{"subitem_language":"jpn"}]},"item_resource_type":{"attribute_name":"資源タイプ","attribute_value_mlt":[{"resourcetype":"technical report","resourceuri":"http://purl.org/coar/resource_type/c_18gh"}]},"item_title":"低速風洞縮流胴における境界層遷移過程","item_titles":{"attribute_name":"タイトル","attribute_value_mlt":[{"subitem_title":"低速風洞縮流胴における境界層遷移過程"}]},"item_type_id":"3","owner":"1","path":["1893","1917"],"pubdate":{"attribute_name":"公開日","attribute_value":"2015-03-26"},"publish_date":"2015-03-26","publish_status":"0","recid":"42862","relation_version_is_last":true,"title":["低速風洞縮流胴における境界層遷移過程"],"weko_creator_id":"1","weko_shared_id":-1},"updated":"2023-06-20T22:23:02.177245+00:00"}