{"created":"2023-06-20T15:10:44.183892+00:00","id":40310,"links":{},"metadata":{"_buckets":{"deposit":"7ff74143-a098-4276-b3fc-fcf756400dfb"},"_deposit":{"created_by":1,"id":"40310","owners":[1],"pid":{"revision_id":0,"type":"depid","value":"40310"},"status":"published"},"_oai":{"id":"oai:jaxa.repo.nii.ac.jp:00040310","sets":["1887:1893","1896:1898:1913:1917"]},"author_link":["447265","447264"],"item_3_alternative_title_1":{"attribute_name":"その他のタイトル","attribute_value_mlt":[{"subitem_alternative_title":"リッド駆動型平方キャビティ内の非圧縮粘性流のNWT計算機システムでの並列計算およびプログラム性能"}]},"item_3_biblio_info_10":{"attribute_name":"書誌情報","attribute_value_mlt":[{"bibliographicIssueDates":{"bibliographicIssueDate":"1998-10","bibliographicIssueDateType":"Issued"},"bibliographicPageEnd":"40","bibliographicPageStart":"1","bibliographicVolumeNumber":"1363T","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":"1993年2月に運用を開始した航空宇宙技術研究所の数値風洞(NWT)計算機システムは、並列計算機システムであり、2台の制御計算機、n台の要素計算機(nの値は運用開始時において140台、現在は166台)並びにクロスバーネットワークから構成されていて、分散メモリ型メッセージパッシング方式のMIMD(複数命令列複数データ処理)計算機として動作する。各要素計算機自体はベクトル計算機である。本研究では、まず、並列処理により、実際に流れ場の数値計算がどの程度の精度で可能であるかを調べるため、リッド駆動型平方キャビティ内の非圧縮粘性流れの問題を題材として、それを非スタガードグリッド上でのコンシステントな有限差分スキームで数値解を求めた。その際使用する解法として、ヤコビー法/レッド・ブラック法/CG(コンピュータグラフィックス)法/ADI(交互方向法)法の4つの反復解法を取り上げた。その結果を示すために、Re(レイノルズ数)の0〜10(exp 5)の範囲での変化に応じた平方キャビティ内流れ変化の様相を詳細に調べた。その並列処理精度の程度を、使用要素計算機台数を変化させて詳細に調べるとともに、使用反復解法および使用グリッドサイズに応じても詳細に調べた。次に、各種プログラム処理速度を、使用要素計算機の台数を増大させることによって詳細に調べた。さらに、その処理速度に限界をもたらす各種のシステム・オーバヘッドはどの程度のものかを評価するため、システムオーバヘッドの主要因である、FORTRANプログラムに挿入されるコンパイラ・ディレクティブの1つ1つについて、それぞれのオーバヘッドを詳細に調べた。最後に、他の計算機との比較のために、一般的に用いられているプログラム処理性能を表すNWTの特性パラメータを推定した。並列プログラムの実効処理性能を使用要素計算機台数の関数として見た場合の特性パラメータと、並列プログラムの実効処理性能をグリッド・サイズの関数として見た場合の特性パラメータとを推定した。この1年間におけるシステム・ソフトウェアの改善努力の結果、約3倍の処理速度の向上が得られた。","subitem_description_type":"Abstract"}]},"item_3_description_17":{"attribute_name":"抄録（英）","attribute_value_mlt":[{"subitem_description":"The NWT (Numerical Wind Tunnel) computer system available at the NAL (National Aerospace Laboratory) since February 1993 comprises two system administrators, n processing elements (where n was 140 at the beginning, and is 166 at present) and a crossbar network, and operates as a distributed-memory message-passing MIMD (Multiple Instruction and Multiple Data stream) computer. Each processing element itself is a vector computer. This paper reports parallel computations of incompressible viscous flow in a lid-driven square cavity on the NWT computer system. In order to obtain numerical solutions of this flow, consistent finite-difference approximations on nonstaggered grids and four iterative solution methods are used. Computations are performed on the Reynolds number range of Re = 0 to 10(exp 5), and effects of the Reynolds number, number of processing elements (pe) in the parallel processing, solution method and grid size on the computational results are examined. Actual rates of the parallelized square cavity programs on the NWT computer system are measured, and two characteristic parameters of these programs are estimated for the cases that the actual rate is considered as a function of pe and that the actual rate is considered as a function of the grid size. Measurements of the maximum actual rate and estimations of the speedup and efficiency against pe on the NWT computer system are indicated as well.","subitem_description_type":"Other"}]},"item_3_description_32":{"attribute_name":"資料番号","attribute_value_mlt":[{"subitem_description":"資料番号: AA0001670000","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-1363T","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":"0389-4010","subitem_source_identifier_type":"ISSN"}]},"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 数理解析部"}]},"item_3_text_7":{"attribute_name":"著者所属（英）","attribute_value_mlt":[{"subitem_text_language":"en","subitem_text_value":"National Aerospace Laboratory Computational Sciences Division"}]},"item_creator":{"attribute_name":"著者","attribute_type":"creator","attribute_value_mlt":[{"creatorNames":[{"creatorName":"畑山, 茂樹"}],"nameIdentifiers":[{}]},{"creatorNames":[{"creatorName":"Hatayama, Shigeki","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":"2020-01-27"}],"displaytype":"detail","filename":"naltr0001363t.pdf","filesize":[{"value":"1.9 MB"}],"format":"application/pdf","licensetype":"license_note","mimetype":"application/pdf","url":{"label":"naltr0001363t.pdf","url":"https://jaxa.repo.nii.ac.jp/record/40310/files/naltr0001363t.pdf"},"version_id":"3b1f2e7b-b80e-4333-b70a-39ab6e0d829c"}]},"item_keyword":{"attribute_name":"キーワード","attribute_value_mlt":[{"subitem_subject":"数値風洞シミュレーション","subitem_subject_scheme":"Other"},{"subitem_subject":"平方キャビティ","subitem_subject_scheme":"Other"},{"subitem_subject":"非圧縮粘性流","subitem_subject_scheme":"Other"},{"subitem_subject":"マルチコンピュータシステム","subitem_subject_scheme":"Other"},{"subitem_subject":"並列計算機","subitem_subject_scheme":"Other"},{"subitem_subject":"数値流れ解析","subitem_subject_scheme":"Other"},{"subitem_subject":"並列処理","subitem_subject_scheme":"Other"},{"subitem_subject":"並列計算","subitem_subject_scheme":"Other"},{"subitem_subject":"計算機処理性能","subitem_subject_scheme":"Other"},{"subitem_subject":"プログラム処理速度","subitem_subject_scheme":"Other"},{"subitem_subject":"有限差分近似","subitem_subject_scheme":"Other"},{"subitem_subject":"データ転送オーバヘッド","subitem_subject_scheme":"Other"},{"subitem_subject":"numerical wind tunnel simulation","subitem_subject_language":"en","subitem_subject_scheme":"Other"},{"subitem_subject":"square cavity","subitem_subject_language":"en","subitem_subject_scheme":"Other"},{"subitem_subject":"incompressible viscous flow","subitem_subject_language":"en","subitem_subject_scheme":"Other"},{"subitem_subject":"multicomputer system","subitem_subject_language":"en","subitem_subject_scheme":"Other"},{"subitem_subject":"parallel computer","subitem_subject_language":"en","subitem_subject_scheme":"Other"},{"subitem_subject":"numerical flow analysis","subitem_subject_language":"en","subitem_subject_scheme":"Other"},{"subitem_subject":"parallel processing","subitem_subject_language":"en","subitem_subject_scheme":"Other"},{"subitem_subject":"parallel computation","subitem_subject_language":"en","subitem_subject_scheme":"Other"},{"subitem_subject":"computer processing performance","subitem_subject_language":"en","subitem_subject_scheme":"Other"},{"subitem_subject":"program processing speed","subitem_subject_language":"en","subitem_subject_scheme":"Other"},{"subitem_subject":"finite difference approximation","subitem_subject_language":"en","subitem_subject_scheme":"Other"},{"subitem_subject":"data transfer overhead","subitem_subject_language":"en","subitem_subject_scheme":"Other"}]},"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":"technical report","resourceuri":"http://purl.org/coar/resource_type/c_18gh"}]},"item_title":"Parallel computations of incompressible viscous flow in a lid-driven square cavity and program performance on the NWT computer system","item_titles":{"attribute_name":"タイトル","attribute_value_mlt":[{"subitem_title":"Parallel computations of incompressible viscous flow in a lid-driven square cavity and program performance on the NWT computer system","subitem_title_language":"en"}]},"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":"40310","relation_version_is_last":true,"title":["Parallel computations of incompressible viscous flow in a lid-driven square cavity and program performance on the NWT computer system"],"weko_creator_id":"1","weko_shared_id":1},"updated":"2023-06-20T19:15:44.051698+00:00"}