{"created":"2023-06-20T13:21:19.691948+00:00","id":1495,"links":{},"metadata":{"_buckets":{"deposit":"c0c04099-1cb3-4f43-aa02-b132d403bd90"},"_deposit":{"created_by":21,"id":"1495","owners":[21],"pid":{"revision_id":0,"type":"depid","value":"1495"},"status":"published"},"_oai":{"id":"oai:ir.soken.ac.jp:00001495","sets":["2:428:14"]},"author_link":["0","0","0"],"item_1_creator_2":{"attribute_name":"著者名","attribute_type":"creator","attribute_value_mlt":[{"creatorNames":[{"creatorName":"RUWALI, Kailash"}],"nameIdentifiers":[{}]}]},"item_1_creator_3":{"attribute_name":"フリガナ","attribute_type":"creator","attribute_value_mlt":[{"creatorNames":[{"creatorName":"ルワリ, カイラシ"}],"nameIdentifiers":[{}]}]},"item_1_date_granted_11":{"attribute_name":"学位授与年月日","attribute_value_mlt":[{"subitem_dategranted":"2009-09-30"}]},"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（理学）"}]},"item_1_description_12":{"attribute_name":"要旨","attribute_value_mlt":[{"subitem_description":" One of the most prominent applications of superconductivity is high field
magnet. Mechanical disturbance such as abrupt conductor motion is one of the main
origin of premature quench (transition from superconducting state to the normal
resistive state) in high current density superconducting coils. The wire motion occurs
when electromagnetic force to conductor exceeds constrain force including frictional
force on the surface of conductor. Behavior of superconducting wire motion depends
on the electromagnetic force acting on it, frictional property of the insulating material
and thrust force applied to the superconducting wire.
The experiments for superconducting wire motion in magnetic field was
carried out using small coil wound on stainless steel (SUS) bobbin using Polyimide
film as an insulating material and high strength polyethylene fiber (Dyneema: DF)
reinforced plastic (DFRP) bobbin [1]. The Dyneema fiber has negative thermal
expansion [2] and low coefficient of friction [3]. It was found that voltage spikes
generated due to sudden wire motion in case of DFRP bobbin are a few and small in
amplitude. The speculations are; the negative thermal expansion of the DFRP bobbin
restrains the wire motion and low coefficient of friction between superconducting
wire and DFRP bobbin reduces sudden motion.
In order to study the effect of frictional coefficient of insulating material on
superconducting wire motion under the influence of electromagnetic force, a special
experimental setup was designed and fabricated. The main distinctiveness of the
experimental setup is that the tension of the superconducting wire can be changed
during the experiments. The experimental set up consists of a cryostat,
superconducting solenoid magnet, sample holder, tensional unit to apply tension to
the superconducting wire, power supplies and pen recorder or a 16-bit data recorder
to measure the voltage tap signal. The sample holder consists of two parts, a semi-
circular head and a body part. Experiments were conducted at 4.2 K by varying the
experimental conditions such as the tension to the superconducting wire,
superconducting wire current ramp rate and different insulating materials at the
interface of the superconducting wire and semi-circular head.
Voltage taps to measure the signal generated due to the superconducting wire
motion are connected at the end of the semi-circular head. To reduce the voltage tap
loop area, a groove was incorporated in the semi-circular head and the voltage tap
wire was passed through it. The voltage tap signal is measured by a pen recorder or a
16-bit data recorder with a sampling rate of 1 MS/s. Sudden wire motion was
indicated by observing the voltage spikes.
In order to examine the effect of the current ramp rate on the superconducting
wire motion, ramp rate was changed from 0.4 A/s to 1.69 A/s. The superconducting
wire tension was varied from 7.1 N to 35.8 N to study the effect of tension on the
superconducting wire motion. During all experiments, a constant magnetic field of 6
T was applied by superconducting solenoid magnet.
In the thesis work, different types of insulating material were used to study
superconducting wire motion under electromagnetic force. They are Polyimide film,
cloth / sheet material fabricated using Dyneema fiber, Zylon fiber and Teflon. The
Dyneema / Zylon fiber has negative thermal expansion and a low coefficient of
friction.
We have verified the effectiveness of this system. We could measure the
pattern of voltage spikes. The time duration of voltage spikes are of the same order
for all the samples. The peak voltage tap signal amplitude, velocity of wire motion,
distance moved by wire and energy dissipated due to wire motion in case of
Polyimide film is more than 2 order of magnitude larger than Dyneema based
insulating materials and Zylon cloth. Hence use of Dyneema / Zylon based materials
as an interface material between layers of superconducting wire may reduce the
frictional heat generated due to wire motion and could make superconducting magnet
performance more reliable.","subitem_description_type":"Other"}]},"item_1_description_18":{"attribute_name":"フォーマット","attribute_value_mlt":[{"subitem_description":"application/pdf","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1280号","subitem_description_type":"Other"}]},"item_1_select_14":{"attribute_name":"所蔵","attribute_value_mlt":[{"subitem_select_item":"有"}]},"item_1_select_8":{"attribute_name":"研究科","attribute_value_mlt":[{"subitem_select_item":"高エネルギー加速器科学研究科"}]},"item_1_select_9":{"attribute_name":"専攻","attribute_value_mlt":[{"subitem_select_item":"12 加速器科学専攻"}]},"item_1_text_10":{"attribute_name":"学位授与年度","attribute_value_mlt":[{"subitem_text_value":"2009"}]},"item_creator":{"attribute_name":"著者","attribute_type":"creator","attribute_value_mlt":[{"creatorNames":[{"creatorName":"RUWALI, Kailash","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":"2016-02-17"}],"displaytype":"simple","filename":"甲1280_要旨.pdf","filesize":[{"value":"174.3 kB"}],"format":"application/pdf","licensetype":"license_11","mimetype":"application/pdf","url":{"label":"要旨・審査要旨","url":"https://ir.soken.ac.jp/record/1495/files/甲1280_要旨.pdf"},"version_id":"2ef2a269-0501-40a5-a075-b549b3baa704"},{"accessrole":"open_date","date":[{"dateType":"Available","dateValue":"2016-02-17"}],"displaytype":"simple","filename":"甲1280_本文.pdf","filesize":[{"value":"4.0 MB"}],"format":"application/pdf","licensetype":"license_11","mimetype":"application/pdf","url":{"label":"本文","url":"https://ir.soken.ac.jp/record/1495/files/甲1280_本文.pdf"},"version_id":"5abf1cc1-332c-486d-ba57-132c5cf2ee89"}]},"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":"Experimental study of superconducting wire motion on the base insulating material in magnetic field","item_titles":{"attribute_name":"タイトル","attribute_value_mlt":[{"subitem_title":"Experimental study of superconducting wire motion on the base insulating material in magnetic field"},{"subitem_title":"Experimental study of superconducting wire motion on the base insulating material in magnetic field","subitem_title_language":"en"}]},"item_type_id":"1","owner":"21","path":["14"],"pubdate":{"attribute_name":"公開日","attribute_value":"2010-06-09"},"publish_date":"2010-06-09","publish_status":"0","recid":"1495","relation_version_is_last":true,"title":["Experimental study of superconducting wire motion on the base insulating material in magnetic field"],"weko_creator_id":"21","weko_shared_id":-1},"updated":"2023-06-20T15:59:11.210823+00:00"}