{"created":"2023-06-20T15:09:37.099210+00:00","id":5595,"links":{},"metadata":{"_buckets":{"deposit":"2fa05d70-6107-4585-a620-f03ff916c118"},"_deposit":{"created_by":17,"id":"5595","owners":[17],"pid":{"revision_id":0,"type":"depid","value":"5595"},"status":"published"},"_oai":{"id":"oai:ynu.repo.nii.ac.jp:00005595","sets":["553:556"]},"author_link":["27699","27698"],"item_7_alternative_title_21":{"attribute_name":"その他のタイトル","attribute_value_mlt":[{"subitem_alternative_title":"フラップ設置による箱桁渦励振の制振メカニズムに関する数値解析検討","subitem_alternative_title_language":"ja"}]},"item_7_biblio_info_8":{"attribute_name":"書誌情報","attribute_value_mlt":[{"bibliographicIssueDates":{"bibliographicIssueDate":"2014-09-25","bibliographicIssueDateType":"Issued"}}]},"item_7_date_granted_66":{"attribute_name":"学位授与年月日","attribute_value_mlt":[{"subitem_dategranted":"2014-09-25"}]},"item_7_degree_grantor_64":{"attribute_name":"学位授与機関","attribute_value_mlt":[{"subitem_degreegrantor":[{"subitem_degreegrantor_name":"横浜国立大学"}],"subitem_degreegrantor_identifier":[{"subitem_degreegrantor_identifier_name":"12701","subitem_degreegrantor_identifier_scheme":"kakenhi"}]}]},"item_7_degree_name_63":{"attribute_name":"学位名","attribute_value_mlt":[{"subitem_degreename":"博士(工学)"}]},"item_7_description_5":{"attribute_name":"抄録","attribute_value_mlt":[{"subitem_description":"Aerodynamic countermeasures are concerned as effective control solutions to wind-induced vibrations mitigation in long span bridges. In order to decide a specific aerodynamic countermeasure, many experimental tests must be conducted case by case in wind tunnel, appearing some difficulties involved. Up to now, there has not yet been any common guideline in the selection of aerodynamic countermeasures. Hence, an effort of establishing the guideline is necessary in wind resistant design process.This thesis focuses on the suppression mechanism of Vortex Induced Vibration (VIV) for box girder having a bluff-body shape in the presence of flap countermeasure. The effect of flap is investigated through Computational Fluid Dynamics (CFD) approach. In there, various geometric configurations of flap are examined thoroughly. The study is considered as a contribution of the fundamental guideline to flap application.The Reynolds Averaged Navier-Stokes (RANS) method coupled with a new eddy viscosity turbulent model is applied. The validation of numerical simulations is confirmed by means of the comparison with experimental results. The numerical investigation is carried out in two main parts comprising static and dynamic simulations. Particularly, the aerodynamic instability characteristics, together with the pattern of wind flow, are estimated by the results obtained from the static simulations. Then, the flutter derivative calculated from the dynamic simulations is taken into account to assess the change of aerodynamic damping for each case of flap attached. In addition, some rectangular sections with flap installed are also inspected to reinforce the findings in the study. Finally, the conclusions outline the achievements and findings, as well as the direction of future research.The thesis is arranged in seven chapters and the contents are sketched as follows:- Chapter 1 introduces the general information regarding the impact of wind on long span bridges, especially on substructure. Then, the necessary of this research is presented. On the other hand, this chapter clearly defines the research aim, scope, objectives and methodology.- Chapter 2 presents the theory of wind effects on bridge girder. Firstly, wind induced vibrations are clearly mentioned in company with estimation and calculation methods. Then, the theory of wind resistant design is carefully provided in case of long span bridge girder. Finally, the effect of aerodynamic countermeasures is given in some cases of real bridges. This chapter is concern as a fundamental theory part which is used to investigate the numerical results.- Chapter 3 provides the theory of CFD with basic concepts such as the equations describing fluid flow, CFD application, discretization, finite volume method…In addition, turbulence models are systematically summarized. More particularly, the turbulence model used in this study is presented to make bases for the numerical simulations.- Chapter 4 discusses about wind tunnel tests in general, the experimental data collection of a real bridge girder and several cases of rectangular cross-sections in some past researches. The data gathered in this chapter is vital basic to confirm the validation of all numerical simulations analyzed.- Chapter 5 deals with the numerical investigation into static simulations. Numerical simulation properties are described in detail. The aerodynamic characteristics of the box section as well as some rectangular sections and the effect of flap with various geometry configurations are analyzed. The flow pattern is observed to clarify the suppression mechanism of VIV. On the other hand, a side effect to vehicle of flap is also discussed.- Chapter 6 solves with the numerical investigation into dynamic simulations. Numerical simulation procedure is mentioned similarly as chapter 5. Flutter derivative calculated from the results obtained in dynamic simulations is discussed to support more the confirmation for the effect of flap.- Chapter 7 gives some conclusions basing the achieved results in flap application. The perspective of future researches is also recommended in this chapter.","subitem_description_type":"Abstract"}]},"item_7_dissertation_number_67":{"attribute_name":"学位授与番号","attribute_value_mlt":[{"subitem_dissertationnumber":"甲第5号"}]},"item_7_full_name_2":{"attribute_name":"著者(ヨミ)","attribute_value_mlt":[{"nameIdentifiers":[{"nameIdentifier":"27699","nameIdentifierScheme":"WEKO"}],"names":[{"name":"ダット, アン トラン"}]}]},"item_7_subject_24":{"attribute_name":"国立国会図書館分類","attribute_value_mlt":[{"subitem_subject":"UT51","subitem_subject_scheme":"NDLC"}]},"item_7_text_4":{"attribute_name":"著者所属","attribute_value_mlt":[{"subitem_text_value":"Graduate School of Urban Innovation, Yokohama National University"}]},"item_7_text_65":{"attribute_name":"学位授与年度","attribute_value_mlt":[{"subitem_text_value":"2014年度"}]},"item_7_version_type_18":{"attribute_name":"著者版フラグ","attribute_value_mlt":[{"subitem_version_resource":"http://purl.org/coar/version/c_970fb48d4fbd8a85","subitem_version_type":"VoR"}]},"item_access_right":{"attribute_name":"アクセス権","attribute_value_mlt":[{"subitem_access_right":"open access","subitem_access_right_uri":"http://purl.org/coar/access_right/c_abf2"}]},"item_creator":{"attribute_name":"著者","attribute_type":"creator","attribute_value_mlt":[{"creatorNames":[{"creatorName":"Tran, Dat Anh","creatorNameLang":"en"}],"nameIdentifiers":[{"nameIdentifier":"27698","nameIdentifierScheme":"WEKO"}]}]},"item_files":{"attribute_name":"ファイル情報","attribute_type":"file","attribute_value_mlt":[{"accessrole":"open_date","date":[{"dateType":"Available","dateValue":"2016-09-20"}],"displaytype":"detail","filename":"dat_anh_tran-thesis.pdf","filesize":[{"value":"8.6 MB"}],"format":"application/pdf","licensetype":"license_note","mimetype":"application/pdf","url":{"label":"dat_anh_tran-thesis.pdf","objectType":"fulltext","url":"https://ynu.repo.nii.ac.jp/record/5595/files/dat_anh_tran-thesis.pdf"},"version_id":"fdc39f14-3478-45da-b383-ee6dd706cbc2"},{"accessrole":"open_date","date":[{"dateType":"Available","dateValue":"2016-09-20"}],"displaytype":"detail","filename":"dat_anh_tran-review.pdf","filesize":[{"value":"465.0 kB"}],"format":"application/pdf","licensetype":"license_note","mimetype":"application/pdf","url":{"label":"dat_anh_tran-review.pdf","url":"https://ynu.repo.nii.ac.jp/record/5595/files/dat_anh_tran-review.pdf"},"version_id":"23e4560c-ff17-4048-9308-31eba02e8fc2"}]},"item_language":{"attribute_name":"言語","attribute_value_mlt":[{"subitem_language":"eng"}]},"item_resource_type":{"attribute_name":"資源タイプ","attribute_value_mlt":[{"resourcetype":"doctoral thesis","resourceuri":"http://purl.org/coar/resource_type/c_db06"}]},"item_title":"Numerical investigation into the suppression mechanism of vortex-induced vibration for box girder in the presence of flap","item_titles":{"attribute_name":"タイトル","attribute_value_mlt":[{"subitem_title":"Numerical investigation into the suppression mechanism of vortex-induced vibration for box girder in the presence of flap","subitem_title_language":"en"}]},"item_type_id":"7","owner":"17","path":["556"],"pubdate":{"attribute_name":"PubDate","attribute_value":"2014-12-26"},"publish_date":"2014-12-26","publish_status":"0","recid":"5595","relation_version_is_last":true,"title":["Numerical investigation into the suppression mechanism of vortex-induced vibration for box girder in the presence of flap"],"weko_creator_id":"17","weko_shared_id":-1},"updated":"2024-03-08T01:25:14.479116+00:00"}