1992 Fiscal Year Final Research Report Summary
Research and Development of a Heat-Transfer Controlled, Long, Slender Cryoprobe
| Project/Area Number |
02555044
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| Research Category |
Grant-in-Aid for Developmental Scientific Research (B)
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| Allocation Type | Single-year Grants |
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| Research Field |
Thermal engineering
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| Research Institution | TOHOKU UNIVERSITY |
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Principal Investigator |
AIHARA T. Tohoku University, Institute of Fluid Science, Professor, 流体科学研究所, 教授 (90006172)
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| Co-Investigator(Kenkyū-buntansha) |
藤間 克己 前川製作所, 技術研究所, 研究員
笠原 敬介 前川製作所, 副社長
鈴木 和弥 前川製作所, 技術研究所, 研究員
OHARA T. Tohoku University, Institute of Fluid Science, Research Associate, 流体科学研究所, 助手 (40211833)
KASAHARA K. Mayekawa MFG.Co.Ltd., Vice President
FUJIMA K. Mayekawa MFG.Co.Ltd., Research Engineer
SUZUKI K. Mayekawa MFG.Co.Ltd., Research Engineer
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| Project Period (FY) |
1990 – 1992
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| Keywords | Cryoprobe / Cryosurgery / Boiling Heat Transfer / Cryogenics / Impinging Jet / Forced Convection / Heat Transfer / Vacuum Thermal Insulation |
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| Research Abstract |
A novel flexible, long slender cryoprobe with a vacuum insulation layer of outer-most diameter 2.1mm and length 1m has been developed for cryosurgery by freezing rapidly a target tissue and necrosing it. The tip of the cryoprobe was cooled by a micro-impinging jet of liquid nitrogen(LN_2). This cryoprobe enables us to perform cryosurgical treatment by inserting it into the channel for vivisectional inspection forceps which is installed within a commercial endoscope, in order to remove polyps or malignancies or cancers formed on the gullet and stomach. The boiling heat transfer characteristics of the micro-impinging jet were investigated in detail using three types of probe tips : a hemispherical surface and flat surfaces with and without a needle. The effects of the mass flow rate of LN_2, jet mouth-to tip distance, shape of the probe tip, and surface roughness on boiling heat transfer were examined experimentally. The probe tip with the hemispherical surface finished with a sandpaper of emery No.500 showed the best cooling performance for cryosurgery. The maximum cooling heat flux of 1.5 MWm^<-2> was attained. Furthermore, for the purpose of practical application, the vacuum thermal insulation characteristics of the probe body and the transient cooling performance of the probe tip were investigated in detail. The design and operation guide to practical use are also given in this report.
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