基本情報
- 所属
- 国立研究開発法人宇宙航空研究開発機構 宇宙科学研究所 教授
- 学位
- 博士(工学)(1996年3月 名古屋大学)
- 連絡先
- ogawa.hiroyuki
jaxa.jp - J-GLOBAL ID
- 200901051344540154
- researchmap会員ID
- 1000253790
- 外部リンク
将来の科学衛星に向けた先進的熱制御システムの研究
科学衛星プロジェクトの経験を基に，現状の課題と将来計画を分析し，将来の科学衛星に必要な先進的熱制御システムの研究開発をおこなっています．研究成果はX線天文衛星ひとみに搭載された熱制御システムにフィードバックされている他，次期科学衛星計画への適用が検討されている等，科学衛星の可能性を広げ，世界一流の成果を創出する活動に貢献しています．
科学衛星プロジェクトの熱制御
日欧水星探査計画BepiColombo等のこれまで経験のない極限環境に晒される探査機や，X線大型望遠鏡衛星ひとみ等の熱流体デバイスを積極的に採用した挑戦的プロジェクトにおいては，従来の衛星開発手法やその延長線上では対応できず，これまで経験のない新しい衛星開発手法が求められます．極限環境に耐える新規材料開発や熱設計・解析手法の構築，試験設備整備や検証手法の開発など，新しい研究開発を熱流体力学の学術的知見をもって先導し，熱の観点でプロジェクトの成功に貢献しています．
熱流体力学の応用
熱流体とその周辺の学術的知見を基に，さまざまな宇宙科学プロジェクト活動に貢献しています．再使用ロケットの研究では，エンジン流れや極低温タンク，外部流等熱流体にかかわる課題解決に貢献しています．衛星推進系ではヒドラジンスラスタ内部化学反応流の研究によりスラスタ解析技術の向上に貢献し，ロケット推進系では固体ロケット内部流解析手法を開発し，M-VロケットやSRB-Aの不具合原因究明に貢献しました．その他，ロケットの飛行安全やロケット排気プルームの電波干渉問題等に関わり，ロケット研究に貢献しています．また高速電磁流体中の衝撃波干渉の理論研究や電磁流体を利用した推進システムの研究をおこないました．
経歴
6-
2017年1月 - 現在
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2003年10月 - 2016年12月
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2002年1月 - 2003年9月
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1998年4月 - 2001年12月
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1996年4月 - 1998年3月
学歴
1-
- 1996年3月
委員歴
1-
2013年3月 - 2015年2月
受賞
1-
2015年
論文
95-
Applied Thermal Engineering 264 2025年4月1日A loop heat pipe is a two-phase fluid loop driven by capillary force. Fabrication of a loop heat pipe evaporator by additive manufacturing has been investigated as a low-cost, quick-delivery method for producing a high-performance loop heat pipe. This study investigated the evaporation and heat transfer performance of a wick-integrated evaporator fabricated by additive manufacturing. It is essential to understand the thermal characteristics of the evaporator for a loop heat pipe with an additive-manufactured evaporator for all applications. A tested loop heat pipe with an additive-manufactured evaporator achieved a maximum heat transport capability of 120 W (heat flux: 7.96 W/cm2) and a minimum thermal resistance of 0.321 °C/W in the horizontal orientation at a 20 °C sink temperature. The evaporative heat transfer coefficient and heat leak ratio to the reservoir were calculated for each orientation test result. The maximum evaporative heat transfer coefficient was 50 kW/m2/K and the heat leak ratio was less than 10 % between 10 W and 70 W in the horizontal orientation. These results reveal that the increase in heat leakage to the reservoir due to the decrease in the evaporative heat transfer coefficient leads to the increase in the loop heat pipe operating temperature and thermal resistance. The novelty of this study is that it clarifies the relationship between a loop heat pipe's thermal resistance and evaporator thermal performance by correlating the evaporative heat transfer coefficient and the heat leakage of the wick-integrated evaporator, which uses additive manufacturing, based on the heat transport test results in each orientation.
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International Journal of Thermal Sciences 207 2025年1月A cryogenic capillary pumped loop (CCPL) is a highly efficient two-phase capillary-force-driven heat transport device that operates at cryogenic temperatures. CCPL satisfies the demands for space applications in cryogenic regions as it can transport heat over long distances without mechanical moving parts. In this study, the transient internal flow during the supercritical startup of CCPL was predicted, and various temperature relationships were used to determine whether CCPL starts up or not. The utilized CCPL comprised a wick (pore radius = 1.0 μm), exhibited a heat transport distance of 2 m, and was filled with nitrogen as the working fluid. The supercritical startup experiments were performed at a temperature range of 77–300 K; the startup procedure was initiated when the maximum temperature of CCPL decreased to ∼150 K. Three different liquid supply cycles were tested during the supercritical startup, and the startup time was reduced (a maximum and minimum of 4.1 and 1.9 h, respectively). CCPL started when the evaporator temperature was below the cold reservoir temperature. Thus, the temperature relationship between the cold reservoir and evaporator at the time of applying the heat load to the evaporator could be used to determine the possibility of starting CCPL. The startup was considered successful when the cold reservoir temperature was higher than the evaporator temperature, as the cold reservoir, which exhibited a two-phase state, supplied sufficient liquid to the evaporator, filling the inside of the evaporator with liquid.
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International Journal of Heat and Mass Transfer 231 2024年10月This paper investigated the effect of filling pressure on the operating characteristics of a gravity-assisted cryogenic loop heat pipe(CLHP) for use in gravity environments such as terrestrial and lunar environments. The CLHP wick is made of sintered stainless-steel fibers with a pore radius of 1.56 μm and designed with a heat transport distance of 2.05 m. The experiments were conducted under gravity-assisted conditions (the condenser was placed 0.1 m higher than the evaporator). Notably, the filling pressure originated from the assumed vapor-liquid distribution in the CLHP under steady-state conditions. The filling pressure was varied from 2.9 MPa to 3.4 MPa in 0.1 MPa increments for six different conditions. Specifically, (1) 2.9 MPa and (2) 3.0 MPa are conditions where the heat leakage due to the vapor phase in the evaporator core is large, while (3) 3.1 MPa and (4) 3.2 MPa are conditions where there is no vapor phase in the evaporator core and the surplus vapor phase escapes to the CC. In general, this condition is considered to be the optimum amount of working fluid for room-temperature LHPs when designing. (5) 3.3 MPa and (6) 3.4 MPa are overfilling conditions that cause the CC to be filled with liquid. The results revealed that the higher the filling pressure, the more obvious the variation in operating temperature caused by the transition of drive modes. The maximum heat transfer capability reached 25 W in cases (1)-(4). In cases (5) and (6), the heat transfer capabilities increased to 30 W, although the operating temperature was higher. Furthermore, the hysteresis effect under different filling pressure conditions was newly confirmed. The power cycling experiments demonstrated that hysteresis in the operating temperature occurred at high heat loads and showed a similar trend to the room-temperature LHP.
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Journal of Evolving Space Activities 2 156 2024年7月25日 査読有り
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Applied Thermal Engineering 255 123878-123878 2024年7月One of the main advantages of a cryogenic loop heat pipe (CLHP) is its heat transfer capability over long distances and operability under anti-gravity conditions. However, there are only a few studies on the thermal characteristics of long-distance CLHPs. It is essential to investigate the effect of a hydraulic head on CLHP performance to enhance the utilization of CLHPs in various applications. This study investigated the thermofluidic behaviors of a 2-m nitrogen CLHP with a capillary starter pump (CSP) under horizontal and anti-gravity conditions where the evaporator was 350 mm higher than the condenser. The novelty of the study is to reveal the heat transfer characteristics and operating mechanisms under anti-gravity conditions based on comparisons with experimental results under horizontal conditions. In the CLHP, a fine stainless-steel porous wick with a pore radius of 1.0 μm and permeability of 1.3 × 10−13 m2 was used for an evaporator and the CSP. The lengths of the vapor line, condenser, and liquid line were 2000, 1500, and 2000 mm, respectively. When a heat load of 4 W was applied to the CSP and evaporator, the CLHP successfully started with an initial cooling condition called a supercritical startup under anti-gravity conditions. The startup temperature behaviors were compared under horizontal and anti-gravity conditions. The thermal resistance of the CLHP with a stepped-up evaporator heat load and various CSP heat loads was evaluated for two CLHP orientations. The CLHP stably operated under evaporator heat loads of 4–24 W (horizontal) and 4–20 W (anti-gravity) for three CSP heat loads of 0, 2, and 4 W. The effect of the CLHP orientation on the thermal resistance with various CSP heat loads is discussed. This study enhances the applicability of the long-distance CLHP to various applications with a high degree of postural freedom by revealing the operating mechanism and thermal characteristics of the long-distance CLHP under anti-gravity and horizontal conditions.
MISC
382-
大気球シンポジウム: 2022年度 = Balloon Symposium: 2022 2022年11月大気球シンポジウム 2022年度（2022年11月7-8日. ハイブリッド開催（JAXA相模原キャンパス& オンライン)) Balloon Symposium 2022 (November 7-8, 2022. Hybrid(in-person & online) Conference (Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency (JAXA)(ISAS)), Sagamihara, Kanagawa Japan 著者人数: 26名 資料番号: SA6000177012 レポート番号: isas22-sbs-012
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Space Telescopes and Instrumentation 2022: Optical, Infrared, and Millimeter Wave 2022年8月27日
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33rd International Symposium on Space Technology and Science 2022年3月
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33rd International Symposium on Space Technology and Science 1 n/a 2022年3月This study developed a novel thermal control system to cool detectors of the General AntiParticle Spectrometer (GAPS) before its flights. GAPS is a balloon-borne cosmic-ray observation experiment. In its payload, GAPS contains over 1000 silicon detectors that must be cooled below −40℃. All detectors are thermally coupled to a unique heat-pipe system (HPS) that transfers heat from the detectors to a radiator. The radiator is designed to be cooled below −50℃ during the flight by exposure to space. The pre-flight state of the detectors is checked on the ground at 1 atm and ambient room temperature, but the radiator cannot be similarly cooled. The authors have developed a ground cooling system (GCS) to chill the detectors for ground testing. The GCS consists of a cold plate, a chiller, and insulating foam. The cold plate is designed to be attached to the radiator and cooled by a coolant pumped by the chiller. The payload configuration, including the HPS, can be the same as that of the flight. The GCS design was validated by thermal tests using a scale model. The GCS design is simple and provides a practical guideline, including a simple estimation of appropriate thermal insulation thickness, which can be easily adapted to other applications.
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SPACE TELESCOPES AND INSTRUMENTATION 2022: OPTICAL, INFRARED, AND MILLIMETER WAVE 12180 2022年LiteBIRD is a JAXA-led international project that aims to test representative inflationary models by performing an all-sky cosmic microwave background radiation (CMB) polarization survey for 3 years at the Sun-Earth Lagrangian point L2. We aim to launch LiteBIRD in the late 2020s. The payload module (PLM) is mainly composed of the Low-Frequency Telescope (LFT), the Mid-Frequency Telescope and High-Frequency Telescope (MHFT), and a cryo-structure. To conduct the high-precision and high-sensitivity CMB observations, it is required to cool the telescopes down to less than 5 K and the detectors down to 100 mK. The high temperature stability is also an important design factor. It is essential to design and analyze the cryogenic thermal system for PLM. In this study, the heat balance, temperature distribution, and temperature stability of the PLM for the baseline design are evaluated by developing the transient thermal model. The effect of the Joule-Thomson (JT) coolers cold tip temperature variation, the periodical changes in subK Adiabatic Demagnetization Refrigerator (ADR) heat dissipation, and the satellite spin that generates the variable direction of solar flux incident are implemented in the model. The effect of contact thermal conductance in the LFT and the emissivity of the V-groove on the temperature distribution and heat balance are investigated. Based on the thermal analysis, it was confirmed that the PLM baseline design meets the requirement of the temperature and the cooling capability of the 4K-JT cooler. In addition, the temperatures of the V-groove and the LFT 5-K frame are sufficiently stable for the observation. The temperature stability of the Low Frequency Focal Plane (LF-FP) is also discussed in this paper.
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18th International Conference on Fluid Dynamics 2021年10月
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18th International Conference on Fluid Dynamics 2021年10月
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50th International Conference on Environmental Systems 2021年7月
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50th International Conference on Environmental Systems 2021年7月
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SPACE TELESCOPES AND INSTRUMENTATION 2020: OPTICAL, INFRARED, AND MILLIMETER WAVE 11443 2021年LiteBIRD, the Lite (Light) satellite for the study of B-mode polarization and Inflation from cosmic background Radiation Detection, is a space mission for primordial cosmology and fundamental physics. JAXA selected LiteBIRD in May 2019 as a strategic large-class (L-class) mission, with its expected launch in the late 2020s using JAXA's H3 rocket. LiteBIRD plans to map the cosmic microwave background (CMB) polarization over the full sky with unprecedented precision. Its main scientific objective is to carry out a definitive search for the signal from cosmic inflation, either making a discovery or ruling out well-motivated inflationary models. The measurements of LiteBIRD will also provide us with an insight into the quantum nature of gravity and other new physics beyond the standard models of particle physics and cosmology. To this end, LiteBIRD will perform full-sky surveys for three years at the Sun-Earth Lagrangian point L2 for 15 frequency bands between 34 and 448 GHz with three telescopes, to achieve a total sensitivity of 2.16 mu K-arcmin with a typical angular resolution of 0.5 degrees at 100 GHz. We provide an overview of the LiteBIRD project, including scientific objectives, mission requirements, top-level system requirements, operation concept, and expected scientific outcomes.
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令和2年度宇宙航行の力学シンポジウム = Symposium on Flight Mechanics and Astrodynamics: 2020 2020年12月令和2年度宇宙航行の力学シンポジウム（2020年12月14日-15日. オンライン開催) Symposium on Flight Mechanics and Astrodynamics: 2020 (December 14-15, 2020. Online Meeting) PDF再処理の為、2023年3月8日に差替 資料番号: SA6000164044
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大気球シンポジウム: 2020年度 = Balloon Symposium: 2020 2020年11月大気球シンポジウム 2020年度（2020年11月5-6日. 宇宙航空研究開発機構宇宙科学研究所(JAXA)(ISAS)）, 相模原市, 神奈川県著者人数: 34名資料番号: SA6000151006レポート番号: isas20-sbs-006
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日本物理学会講演概要集(CD-ROM) 75(2) 2020年大気球シンポジウム 2021年度（2021年11月1-2日. オンライン開催) Balloon Symposium 2021 (November 1-2, 2021. Online Meeting) 著者人数: 26名PDF再処理の為、2023年3月24日に差替 資料番号: SA6000166027 レポート番号: isas21-sbs-027
書籍等出版物
1講演・口頭発表等
33-
46th International Conference on Environmental Systems 2016年7月
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第16回宇宙科学シンポジウム 講演集 = Proceedings of the 16th Space Science Symposium 2016年1月 宇宙航空研究開発機構宇宙科学研究所(JAXA)(ISAS)第16回宇宙科学シンポジウム (2016年1月6日-7日. 宇宙航空研究開発機構宇宙科学研究所(JAXA)(ISAS)相模原キャンパス), 相模原市, 神奈川県資料番号: SA6000046247レポート番号: S4-010
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45th International Conference on Environmental Systems 2015年7月
所属学協会
5-
2020年9月
共同研究・競争的資金等の研究課題
10-
日本学術振興会 科学研究費助成事業 2023年4月 - 2027年3月
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日本学術振興会 科学研究費助成事業 2024年4月 - 2026年3月
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日本学術振興会 科学研究費助成事業 2023年4月 - 2026年3月
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日本学術振興会 科学研究費助成事業 基盤研究(B) 2018年4月 - 2021年3月
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日本学術振興会 科学研究費助成事業 挑戦的萌芽研究 2016年4月 - 2018年3月
産業財産権
6学術貢献活動
1-
パネル司会・セッションチェア等, 査読2003年7月 - 現在
● 指導学生等の数
6-
年度2018年度(FY2018)博士課程学生数1
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年度2019年度(FY2019)博士課程学生数2修士課程学生数1学術特別研究員数1
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年度2020年度(FY2020)博士課程学生数1修士課程学生数1学術特別研究員数1
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年度2018年度(FY2018)博士課程学生数1
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年度2019年度(FY2019)博士課程学生数2修士課程学生数1学術特別研究員数1
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年度2020年度(FY2020)博士課程学生数1修士課程学生数1学術特別研究員数1
● 専任大学名
2-
専任大学名東京大学（University of Tokyo)
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専任大学名東京大学（University of Tokyo)
● 所属する所内委員会
6-
所内委員会名研究所会議
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所内委員会名プログラム会議
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所内委員会名信頼性品質会議
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所内委員会名環境・安全管理統括委員会
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所内委員会名ISASニュース編集小委員会
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所内委員会名宇宙科学プログラム技術委員会
