{"_buckets": {"deposit": "1b03634d-1800-48b8-bc85-982873504ed1"}, "_deposit": {"created_by": 1, "id": "535", "owners": [1], "pid": {"revision_id": 0, "type": "depid", "value": "535"}, "status": "published"}, "_oai": {"id": "oai:ir.soken.ac.jp:00000535", "sets": ["12"]}, "author_link": ["0", "0", "0"], "item_1_biblio_info_21": {"attribute_name": "書誌情報（ソート用）", "attribute_value_mlt": [{"bibliographicIssueDates": {"bibliographicIssueDate": "2007-09-28", "bibliographicIssueDateType": "Issued"}, "bibliographic_titles": [{}]}]}, "item_1_creator_2": {"attribute_name": "著者名", "attribute_type": "creator", "attribute_value_mlt": [{"creatorNames": [{"creatorName": "栗, 再新"}], "nameIdentifiers": [{"nameIdentifier": "0", "nameIdentifierScheme": "WEKO"}]}]}, "item_1_creator_3": {"attribute_name": "フリガナ", "attribute_type": "creator", "attribute_value_mlt": [{"creatorNames": [{"creatorName": "リ, ツァイシン"}], "nameIdentifiers": [{"nameIdentifier": "0", "nameIdentifierScheme": "WEKO"}]}]}, "item_1_date_granted_11": {"attribute_name": "学位授与年月日", "attribute_value_mlt": [{"subitem_dategranted": "2007-09-28"}]}, "item_1_degree_grantor_5": {"attribute_name": "学位授与機関", "attribute_value_mlt": [{"subitem_degreegrantor": [{"subitem_degreegrantor_name": "総合研究大学院大学"}]}]}, "item_1_degree_name_6": {"attribute_name": "学位名", "attribute_value_mlt": [{"subitem_degreename": "博士（工学）"}]}, "item_1_description_1": {"attribute_name": "ID", "attribute_value_mlt": [{"subitem_description": "2007507", "subitem_description_type": "Other"}]}, "item_1_description_12": {"attribute_name": "要旨", "attribute_value_mlt": [{"subitem_description": "　　Self-cooled Li and Flibe blankets with V-alloy structure are attractive \u003cbr /\u003econcepts and considered for the LHD-type helical fusion reactor design\u003cbr /\u003e FFHR. Maximum thickness allowed for blanket is 1.2 m in FFHR. Blanket\u003cbr /\u003e functions such as heat removal due to 14 MeV D-T fusion neutrons, breeding\u003cbr /\u003e of tritium fuel and radiation shielding must be fulfilled within this thickness. \u003cbr /\u003e　　　To verify blanket functions, detailed neutronics investigations are \u003cbr /\u003erequired. One of the key options for Li and Flibe blankets is the use of\u003cbr /\u003eneutron multiplier Be because, in spite of potential benefit of Be from\u003cbr /\u003e neutronics aspects, there are some issues specific to Be such as irradiation\u003cbr /\u003e effects. Thus it is necessary to evaluate quantitatively the impact of Be on\u003cbr /\u003e tritium breeding ratio (TBR), radiation shielding and radio activation. For Li \u003cbr /\u003eblanket, it is necessary to apply an electrical insulating coating e.g. Er\u003csmall\u003e2\u003c/small\u003eO\u003csmall\u003e3\u003c/small\u003e, to\u003cbr /\u003ereduce the magnet-hydro dynamic (MHD) pressure drop when Li flows in a\u003cbr /\u003estrong magnetic field. However,  neutronics investigation on the effect of\u003cbr /\u003e Er\u003csmall\u003e2\u003c/small\u003eO\u003csmall\u003e3\u003c/small\u003e is scarce. \u003cbr /\u003e　　　To provide the reactor design with viable data, the neutronics analysis \u003cbr /\u003eprocedure including transport and activation codes and nuclear libraries\u003cbr /\u003e applied to liquid blankets need to be examined and, if necessary, improved.\u003cbr /\u003eFor this purpose, benchmark studies with systematic comparison of\u003cbr /\u003e calculations and experiments are necessary. \u003cbr /\u003e　　　The objectives of the present study are: \u003cbr /\u003e　　　To investigate Li and Flibe blankets for FFHR by neutronics analysis\u003cbr /\u003ewith focus on the effect of Be and Er2O3 coating on TBR, shielding and\u003cbr /\u003eactivation. \u003cbr /\u003e　　　To examine or improve the neutronics calculation procedure for\u003cbr /\u003eapplication to liquid blankets by comparison with activation experiments\u003cbr /\u003eusing D-T neutrons.\u003cbr /\u003e　　　In the neutronics assessment of FFHR, 3 dimension Monte Carlo code\u003cbr /\u003eMCNP-4C with JENDL3.2 pointwise nuclear data file and FISPACTL2001\u003cbr /\u003ecode with EAF-2001 file in 175 energy groups were used for neutron\u003cbr /\u003etransport and activation calculations, respectively. The results obtained are\u003cbr /\u003equalitatively assumed as follows: Use of Be can significantly improve TBR\u003cbr /\u003efor both Li/V-alloy and Flibe/V-alloy blankets. For the Li/V-alloy blanket with\u003cbr /\u003eBe, the shielding property can be greatly improved maintaining the adequate\u003cbr /\u003eTBR. On the other hand, the shielding property of the Flibe/V-alloy blankets\u003cbr /\u003ewith and without external Be is comparable. The quantitative estimate of\u003cbr /\u003ethe effects of Er\u003csmall\u003e2\u003c/small\u003eO\u003csmall\u003e3\u003c/small\u003e coating showed that the activation of the coating could\u003cbr /\u003einfluence, the long-term activation property of the structural components. \u003cbr /\u003eHowever, recycle of materials for the structural components is still feasible\u003cbr /\u003ewith Er\u003csmall\u003e2\u003c/small\u003eO\u003csmall\u003e3\u003c/small\u003e coating in 10μm thickness. With 1μm thickness of the coating,\u003cbr /\u003ethe activation level of the blanket is close to the hands-on recycling limit. \u003cbr /\u003e　　　For the purpose of verifying or improving the neutronics calculation \u003cbr /\u003eprocedure, especially activation analysis of liquid blankets, a series of \u003cbr /\u003eirradiation experiments were performed using Fusion Neutronics Source\u003cbr /\u003e(FNS) at Japan Atomic Energy Agency (JAEA), which is well-suited to\u003cbr /\u003e neutronics study relevant to a D-T fueled reactor. The specimens of\u003cbr /\u003eV-4Cr-4Ti, Er and Teflon in 10 mm×10 mm×0.03-0.1 mm were prepared for\u003cbr /\u003estudying the activation of V-alloy structure, MHD coating of Er\u003csmall\u003e2\u003c/small\u003eO\u003csmall\u003e3\u003c/small\u003e, and F in\u003cbr /\u003emolten salt Flibe, respectively. In addition to the assembly for direct D-T\u003cbr /\u003eneutron irradiation, Be, Li and Li/Be mock-ups were assembled to examine\u003cbr /\u003ethe dependence of the activation on neutron spectrum expected in fusion\u003cbr /\u003eblankets. \u003cbr /\u003e　　　The activities of specimens measured with a high purity Ge detector\u003cbr /\u003ewere compared with the calculations using FISPACT-2001 codes and \u003cbr /\u003eEAF-2001 file. The neutron flux calculated by MCNP-4C was used as input\u003cbr /\u003efile in FISPACTL-2001 calculation.　In this study, the continuous-energy\u003cbr /\u003ecross-section data were also used in activation calculation in the limited\u003cbr /\u003ecases in addition to the data of EAF-2001 in 175 and 315 energy groups. \u003cbr /\u003e　　　Comparison of calculation (175 groups) to experiment (C/E) shows that \u003cbr /\u003ethe values of C/E for most of radioactive nuclides (\u003csup\u003e18\u003c/sup\u003eF, \u003csup\u003e48\u003c/sup\u003eSc, \u003csup\u003e161\u003c/sup\u003eEr, etc)\u003cbr /\u003eproduced by reactions with high-energy threshold lie in the range of 0.8-1.2.\u003cbr /\u003eA significant underestimation for \u003csup\u003e168\u003c/sup\u003eHo (C/E 0.62) was found in D-T neutron\u003cbr /\u003eirradiation case. It could be caused by the effects of coarse energy grouping\u003cbr /\u003enear 14 MeV because \u003csup\u003e168\u003c/sup\u003eEr(n,p)\u003csup\u003e168\u003c/sup\u003e Ho has a threshold energy close to 14 MeV\u003cbr /\u003eand its cross-section rises steeply around 14 MeV. In fact, the C/E value of\u003cbr /\u003e \u003csup\u003e168\u003c/sup\u003eHo calculated with continuous-energy cross-section approached unity. \u003cbr /\u003e　　　The comparisons of activation for \u003csup\u003e171\u003c/sup\u003eEr and \u003csup\u003e52\u003c/sup\u003eV, both of which are the\u003cbr /\u003e products of (n, \u0026Upsilon;) reactions, were performed with activation data in 175, 315\u003cbr /\u003eenergy groups and continuous data. For \u003csup\u003e52\u003c/sup\u003eV, the major contribution is the\u003cbr /\u003ereaction with thermal neutrons. Using 315 group cross sections, C/E values\u003cbr /\u003eof　\u003csup\u003e52\u003c/sup\u003eV show a clear trend approaching to unity relative to those using 175 \u003cbr /\u003eenergy groups case because of the finer group structures in thermal neutrons\u003cbr /\u003erange. The results also agree well with the results using the \u003cbr /\u003econtinuous-energy cross section. The reaction \u003csup\u003e170\u003c/sup\u003eEr(n, \u0026Upsilon;)\u003csup\u003e171\u003c/sup\u003eEr has a huge\u003cbr /\u003eresonance peak at 95 keV. Large overestimations for \u003csup\u003e171\u003c/sup\u003eEr were observed\u003cbr /\u003ewith group data due to the coarse grouping in the resonance region. Use of\u003cbr /\u003econtinuous-energy cross-section provided much better agreement with\u003cbr /\u003e experiment for Be mock-up, where the neutron flux is almost constant with\u003cbr /\u003eenergy in the resonance range. On the other hand, for the case of Be/Li\u003cbr /\u003e mock-up, where the flux rapidly increases with energy in the resonance\u003cbr /\u003e range, large discrepancy (C/E 〜1.17) was observed even with continuous\u003cbr /\u003ecross-section. This result clearly indicates the necessity for re-evaluation of\u003cbr /\u003e the cross-section data of \u003csup\u003e170\u003c/sup\u003eEr(n, \u0026Upsilon;)\u003csup\u003e171\u003c/sup\u003eEr reaction. This issue was disclosed\u003cbr /\u003ethough the comparative examination of C/E in various neutron spectra, and\u003cbr /\u003ethus unique achievement of this study. \u003cbr /\u003e　　　Conclusions of the present study are: \u003cbr /\u003eA) Detailed neutronics characterization of Li and Flibe blankets using\u003cbr /\u003eV-alloy structure for FFHR has, for the first time, been carried out: \u003cbr /\u003e　A-1) Advantage of the use of Be is quantified. With Be, TBR design margin\u003cbr /\u003e　for Li and Flibe blankes could be improved. For Li blanket with Be, the\u003cbr /\u003e　shielding design margin could also be improved with adequate TBR. The\u003cbr /\u003e　results provide information necessary for characterizing trade-off of using\u003cbr /\u003e　Be in Li and Flibe blankets. \u003cbr /\u003e　A-2)The Er\u003csub\u003e2\u003c/sub\u003eO\u003csub\u003e3\u003c/sub\u003e coating induces the long-term radioactivity of Li blanket. \u003cbr /\u003e　However, recycle of structural materials is still feasible with Er\u003csmall\u003e2\u003c/small\u003eO\u003csmall\u003e3\u003c/small\u003e coating\u003cbr /\u003e　in 10μm thickness. Thinner Er\u003csub\u003e2\u003c/sub\u003eO\u003csub\u003e3\u003c/sub\u003e coating is necessary for realizing \u003cbr /\u003e　hands-on recycling.\u003cbr /\u003eB) Experimental studies of activation characteristics for materials in Li and \u003cbr /\u003eFlibe blankets have been carried out using a D-T neutron source, especially\u003cbr /\u003e for the first time for the Er\u003csmall\u003e2\u003c/small\u003eO\u003csmall\u003e3\u003c/small\u003e coating: \u003cbr /\u003e　B-1) For the threshold reactions, where the threshold energy is close 14  MeV \u003cbr /\u003e　and its cross-section rises steeply around 14 MeV, continuous-energy \u003cbr /\u003e　cross-section data is needed.\u003cbr /\u003e　Be2) For the (n, \u0026Upsilon;) reaction with high cross-section at thermal neutrons\u003cbr /\u003e　region, finer grouping is necessary.\u003cbr /\u003e　B-3) Use of continuous-energy cross-section is necessary for (n, \u0026Upsilon;) reaction\u003cbr /\u003e　with dominant resonance peak in medium energy ranges.\u003cbr /\u003e　B-4) The cross section data of \u003csup\u003e170\u003c/sup\u003eEr(n, \u0026Upsilon;)\u003csup\u003e171\u003c/sup\u003eEr needs re-evaluation.", "subitem_description_type": "Other"}]}, "item_1_description_7": {"attribute_name": "学位記番号", "attribute_value_mlt": [{"subitem_description": "総研大甲第1089号", "subitem_description_type": "Other"}]}, "item_1_select_14": {"attribute_name": "所蔵", "attribute_value_mlt": [{"subitem_select_item": "有"}]}, "item_1_select_16": {"attribute_name": "複写", "attribute_value_mlt": [{"subitem_select_item": "application/pdf"}]}, "item_1_select_8": {"attribute_name": "研究科", "attribute_value_mlt": [{"subitem_select_item": "物理科学研究科"}]}, "item_1_select_9": {"attribute_name": "専攻", "attribute_value_mlt": [{"subitem_select_item": "10 核融合科学専攻"}]}, "item_1_text_10": {"attribute_name": "学位授与年度", "attribute_value_mlt": [{"subitem_text_value": "2007"}]}, "item_creator": {"attribute_name": "著者", "attribute_type": "creator", "attribute_value_mlt": [{"creatorNames": [{"creatorName": "LI, Zaixin", "creatorNameLang": "en"}], "nameIdentifiers": [{"nameIdentifier": "0", "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": "2016-02-17"}], "displaytype": "simple", "download_preview_message": "", "file_order": 0, "filename": "甲1089_要旨.pdf", "filesize": [{"value": "358.4 kB"}], "format": "application/pdf", "future_date_message": "", "is_thumbnail": false, "licensetype": "license_11", "mimetype": "application/pdf", "size": 358400.0, "url": {"label": "要旨・審査要旨", "url": "https://ir.soken.ac.jp/record/535/files/甲1089_要旨.pdf"}, "version_id": "fd2a4690-e0c8-4b00-b275-fd418955b95c"}, {"accessrole": "open_date", "date": [{"dateType": "Available", "dateValue": "2016-02-17"}], "displaytype": "simple", "download_preview_message": "", "file_order": 1, "filename": "甲1089_本文.pdf", "filesize": [{"value": "2.9 MB"}], "format": "application/pdf", "future_date_message": "", "is_thumbnail": false, "licensetype": "license_11", "mimetype": "application/pdf", "size": 2900000.0, "url": {"label": "本文", "url": "https://ir.soken.ac.jp/record/535/files/甲1089_本文.pdf"}, "version_id": "976f5114-984f-436a-baad-9abd1c33dfb3"}]}, "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": "thesis", "resourceuri": "http://purl.org/coar/resource_type/c_46ec"}]}, "item_title": "Benchmark study on neutronics performance of liquid blankets", "item_titles": {"attribute_name": "タイトル", "attribute_value_mlt": [{"subitem_title": "Benchmark study on neutronics performance of liquid blankets"}, {"subitem_title": "Benchmark study on neutronics performance of liquid blankets", "subitem_title_language": "en"}]}, "item_type_id": "1", "owner": "1", "path": ["12"], "permalink_uri": "https://ir.soken.ac.jp/records/535", "pubdate": {"attribute_name": "公開日", "attribute_value": "2010-02-22"}, "publish_date": "2010-02-22", "publish_status": "0", "recid": "535", "relation": {}, "relation_version_is_last": true, "title": ["Benchmark study on neutronics performance of liquid blankets"], "weko_shared_id": 1}